Oxygen-absorbing multilayer body, oxygen-absorbing container, oxygen-absorbing airtight container, oxygen-absorbing push-through pack, and storage method using same

Abstract

Provided is an oxygen-absorbing multilayer body including an oxygen-absorbing layer containing an oxygen-absorbing composition and a thermoplastic resin layer containing a thermoplastic resin (b), wherein the oxygen-absorbing composition includes at least one compound having a tetralin ring represented by Formula (1), a transition metal catalyst, and a thermoplastic resin (a). ##STR00001##

Claims

1. An oxygen-absorbing multilayer body comprising: an oxygen-absorbing layer containing an oxygen-absorbing composition; and a thermoplastic resin layer containing a thermoplastic resin (b), wherein the oxygen-absorbing composition comprises at least one compound having a tetralin ring represented by Formula (1), a transition metal catalyst, and a thermoplastic resin (a): ##STR00042## where R.sub.1 to R.sub.12 each independently represent a hydrogen atom or a monovalent substituent, the monovalent substituent being at least one selected from the group consisting of a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, a phenyl group, a naphthyl group, a monovalent substituent having one hydrogen atom removed from a five- or six-membered aromatic or non-aromatic heterocyclic compound having 1 to 12 carbon atoms, a cyano group, a hydroxy group, a carboxyl group, an ester group, an amide group, a nitro group, an alkoxy group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, an imide group, a substituent represented by Formula (1a), and a substituent represented by Formula (1b), which each optionally further have a substituent; two of the substituents represented by R.sub.1 to R.sub.12 are optionally bonded to each other to form an aromatic, aliphatic, or hetero ring having 4 to 7 carbon atoms, provided that the hetero ring is an acid anhydride ring being glutaric anhydride ring or adipic anhydride ring; and at least one hydrogen atom is bonded to a benzylic position of the tetralin ring; ##STR00043## where each R independently represents a monovalent substituent, the monovalent substituent being at least one selected from the group consisting of a halogen atom, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group, a cyano group, a hydroxy group, a carboxyl group, an ester group, an amide group, a nitro group, an alkoxy group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, which each optionally further have a substituent; two of the substituents each represented by R are optionally bonded to each other to form a ring; W represents a bond or a bivalent organic group, the bivalent organic group being at least one selected from the group consisting of an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, a linear or branched saturated or unsaturated aliphatic hydrocarbon group and a heterocyclic group, C(?O), OC(?O), N(H)C(?O), and an arbitrary combination thereof; m represents an integer of 0 to 4; n represents an integer of 0 to 7; p represents an integer of 0 to 8; and q represents an integer of 0 to 3.

2. The oxygen-absorbing multilayer body according to claim 1, wherein the compound having a tetralin ring represented by Formula (1) has two or more carbonyl groups.

3. The oxygen-absorbing multilayer body according to claim 2, wherein in Formula (1), at least two of R.sub.1 to R.sub.12 are monovalent substituents represented by Formula (2):
C(?O)X(2) where X represents one selected from the group consisting of a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, a monoalkylamino group, and a dialkylamino group; and a plurality of X may be the same or different.

4. The oxygen-absorbing multilayer body according to claim 1, wherein the compound having a tetralin ring represented by Formula (1) has two or more tetralin rings.

5. The oxygen-absorbing multilayer body according to claim 1, wherein a proportion of the amount of the compound having a tetralin ring represented by Formula (1) to the total amount of the compound having a tetralin ring represented by Formula (1) and the thermoplastic resin (a) in the oxygen-absorbing composition is 1% to 30% by mass.

6. The oxygen-absorbing multilayer body according to claim 1, wherein the thermoplastic resin (a) is at least one selected from the group consisting of a polyolefin, a polyester, a polyamide, an ethylene-vinyl alcohol copolymer, and a chlorine-containing resin.

7. The oxygen-absorbing multilayer body according to claim 1, wherein the transition metal catalyst contains at least one transition metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper.

8. The oxygen-absorbing multilayer body according to claim 1, wherein the transition metal catalyst is contained in an amount of 0.001 to 10 parts by mass in terms of the transition metal amount, in the oxygen-absorbing composition, based on 100 parts by mass of the total amount of the compound having a tetralin ring represented by Formula (1) and the thermoplastic resin (a).

9. The oxygen-absorbing multilayer body according to claim 1, wherein the thermoplastic resin layer is a sealant layer; and the oxygen-absorbing multilayer body is composed of at least three layers including the sealant layer, the oxygen-absorbing layer, and a gas barrier layer containing a gas barrier material in this order.

10. An oxygen-absorbing paper container prepared by molding an oxygen-absorbing multilayer body being composed of at least four layers including the oxygen-absorbing multilayer body according to claim 9 and a paper base layer laminated to the gas barrier layer side of the oxygen-absorbing multilayer body.

11. An oxygen-absorbing container comprising the oxygen-absorbing multilayer body according to claim 1.

12. The oxygen-absorbing container according to claim 11, being one selected from the group consisting of a pouch, a cup, a tray, and a bottle.

13. The oxygen-absorbing multilayer body according to claim 1, being an oxygen-absorbing multilayer injection-molded article.

14. An oxygen-absorbing sealed container comprising: an oxygen-absorbing multilayer container body prepared by molding the oxygen-absorbing multilayer body according to claim 1; and a gas barrier lid member being composed of at least two layers including an inner layer containing a thermoplastic resin (c) and a gas barrier layer containing a gas barrier material in this order, wherein the thermoplastic resin layer in the oxygen-absorbing container body and the inner layer in the gas barrier lid member are joined to each other.

15. An oxygen-absorbing PTP packaging body comprising: an oxygen-absorbing bottom member prepared by molding the oxygen-absorbing multilayer body according to claim 1; and a gas barrier lid member being composed of at least two layers including an inner layer containing a thermoplastic resin (d) and a gas barrier layer containing a gas barrier material in this order, wherein the thermoplastic resin layer in the oxygen-absorbing bottom member and the inner layer in the gas barrier lid member are joined to each other.

16. A storage method comprising storing at least one selected from the group consisting of cooked rice, an alcoholic beverage, fruit juice and/or vegetable juice, and a drug solution in an oxygen-absorbing container including the oxygen-absorbing multilayer body according to claim 1.

Description

EXAMPLES

(1) The present invention will now be more specifically described by Examples and Comparative Examples, but is not limited to the following Examples. Incidentally, the NMR measurement was performed at room temperature unless specifically indicated otherwise.

First Experiment

Synthesis Example 1

Diester Compound A Having a Tetralin Ring

(2) A reactor equipped with a thermometer, a partial condenser, a total condenser, and a stirrer was charged with 248 g (1.0 mol) of dimethyl 1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate, 409 g (4.0 mol) of n-hexyl alcohol, and 0.34 g of tetrabutyl titanate and was heated to 150? C. in a nitrogen atmosphere while removing the generated methanol to the outside of the reaction system to promote the reaction. After the completion of the generation of methanol, the reaction system was cooled to room temperature, and the unreacted n-hexyl alcohol was removed under reduced pressure to obtain diester compound A. The 3% weight-reduction temperature of the resulting compound was measured with a thermogravimetric/differential thermal analyzer (manufactured by Shimadzu Corporation, trade name DTG-60). The structural formula, molecular weight, and 3% weight-reduction temperature of the resulting compound are shown in Table 1. The results of NMR analysis were as follows.

(3) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.73-7.79 (2H m), 7.16 (1H d), 4.29 (2H t), 4.10 (2H t), 3.01-3.08 (2H m), 2.82-2.97 (2H m), 2.70-2.78 (1H m), 2.18-2.24 (1H m), 1.84-1.94 (1H m), 1.71-1.79 (2H m), 1.58-1.68 (2H m), 1.25-1.48 (12H m), 0.90 (6H t).

Synthesis Example 2

Diester Compound B Having a Tetralin Ring

(4) Diester compound B was prepared by the same procedure as that in Synthesis Example 1 except that 521 g (4.0 mol) of n-octyl alcohol was used instead of n-hexyl alcohol and that the reaction temperature was 190? C. The structural formula of the resulting compound is shown in Table 1. The results of NMR analysis were as follows.

(5) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.68-7.74 (2H m), 7.10 (1H d), 4.23 (2H t), 4.04 (2H t), 2.92-3.00 (2H m), 2.72-2.89 (2H m), 2.63-2.70 (1H m), 2.10-2.18 (1H m), 1.76-1.85 (1H m), 1.63-1.72 (2H m), 1.50-1.59 (2H m), 1.09-1.40 (20H m), 0.90 (6H t).

Synthesis Example 3

Diester Compound C Having a Tetralin Ring

(6) Diester compound C was prepared by the same procedure as that in Synthesis Example 2 except that dimethyl 1,2,3,4-tetrahydronaphthalene-1,8-dicarboxylate was used instead of dimethyl 1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate. The structural formula of the resulting compound is shown in Table 1. The results of NMR analysis were as follows.

(7) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.78 (1H d), 7.17-7.29 (2H m), 4.50 (1H t), 4.22 (2H t), 3.98-4.12 (2H m), 2.76-2.93 (2H m), 2.21-2.30 (1H m), 1.89-1.99 (1H m), 1.67-1.83 (4H m), 1.50-1.63 (3H m), 1.18-1.44 (19H m), 0.89 (6H t).

Synthesis Example 4

Diester Compound D Having a Tetralin Ring

(8) A reactor equipped with a thermometer, a partial condenser, a total condenser, and a stirrer was charged with 108 g (0.62 mmol) of dimethyl adipate and 300 g (1.85 mmol) of 6-hydroxymethyl-1,2,3,4-tetrahydronaphthalene and was heated to 130? C. To the mixture added was 0.58 g of titanium tetrabutoxide. The temperature was raised to 200? C., and the reaction was performed while removing the generated methanol to the outside of the reaction system to promote the reaction. After the completion of the generation of methanol, the reaction system was cooled to room temperature. The unreacted 6-hydroxymethyl-1,2,3,4-tetrahydronaphthalene was removed under reduced pressure, and diester compound D was obtained by recrystallization. The structural formula of the resulting compound is shown in Table 1. The results of NMR analysis were as follows.

(9) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.00 (6H m), 5.02 (4H s), 2.70-2.79 (8H m), 2.34 (4H t), 1.74-1.83 (8H m), 1.64-1.70 (4H m).

Synthesis Example 5

Diamide Compound E Having a Tetralin Ring

(10) A 2000-mL autoclave equipped with a thermometer and a stirrer was charged with 248 g (1.0 mol) of dimethyl 1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate and 607 g (6.0 mol) of n-hexylamine, was purged with nitrogen, was then heated to 220? C., and was stirred at this temperature for 5 hours. After cooling to room temperature, diamide compound E was obtained through filtration and recrystallization. The structural formula of the resulting compound is shown in Table 1. The results of NMR analysis were as follows.

(11) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.42 (1H s), 7.37 (1H d), 7.04 (1H d), 5.99 (1H m), 5.53 (1H m), 3.32-3.41 (2H m), 3.15-3.24 (2H m), 2.68-3.03 (4H m), 2.35-2.43 (1H m), 1.97-2.05 (1H m), 1.76-1.87 (1H m), 1.17-1.58 (12H m), 0.83 (6H t).

Synthesis Example 6

Acid Anhydride F Having a Tetralin Ring

(12) An autoclave having an internal volume of 18 L was charged with 1.8 kg of 1,8-naphthalic anhydride, 300 g of a 5 wt % palladium on activated carbon catalyst (dried product), and 7.5 kg of ethyl acetate. The inside of the autoclave was purged with nitrogen of 1 MPa twice and then with hydrogen of 1 MPa twice at room temperature. Subsequently, the pressure was decreased to ordinary pressure, the internal temperature was increased to 80? C., the pressure was then increased to 5 MPa with hydrogen, and the mixture was stirred at 500 rpm for 2 hours at the same temperature and the same pressure. After the reaction, the autoclave was cooled to room temperature, and the hydrogen was released. After purge with nitrogen of 1 MPa twice, the catalyst was collected by filtration and was washed with 1.0 kg of acetone three times. The solvent in the resulting mother liquor was removed by an evaporator under reduced pressure to obtain a crude product. The resulting crude product was recrystallized to obtain acid anhydride F. The results of NMR analysis were as follows.

(13) .sup.1H-NMR (400 MHz CDCl.sub.3) ? 7.98 (1H d), 7.47 (1H d), 7.38 (1H dd), 3.93 (1H t), 2.80-3.00 (2H m), 2.55-2.64 (1H m), 2.14-2.24 (1H m), 1.77-1.94 (2H m).

(14) TABLE-US-00001 TABLE 1 3% weight- reduction Molecular temperature Compound having tetralin ring weight (? C.) Diester compound A 388.6 237 Diester compound B 444.7 262 Diester compound C 444.7 250 Diester compound D 434.6 263 Diamide compound E 0 386.6 290 Acid anhydride F 202.2 170

Example 1-1

(15) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL L171B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(16) Subsequently, an oxygen-absorbing multilayer sheet was formed with a three-material five-layer multilayer sheet molding apparatus equipped with first to third extruders, a feed block, a T-die, a cooling roll, and a sheet take-up unit by extruding polypropylene (product name: NOVATEC PP FY6C, hereinafter also abbreviated to PP, manufactured by Japan Polypropylene Corporation) from the first extruder, the oxygen-absorbing composition from the second extruder, and adhesive polypropylene (product name: MODIC P604V, hereinafter also abbreviated to adhesive PP, manufactured by Mitsubishi Chemical Corporation) from the third extruder and supplying the extrudates to the feed block. The multilayer sheet had a layer structure composed of PP (250 ?m)/adhesive PP (15 ?m)/oxygen-absorbing layer (100 ?m)/adhesive PP (15 ?m)/PP (250 ?m) in this order from the inner layer. The resulting oxygen-absorbing multilayer sheet was evaluated as follows. (1) Amount of Oxygen Absorbed by Oxygen-Absorbing Multilayer Sheet

(17) Two gas barrier bags made of an aluminum foil laminate film were prepared. Two test pieces (length: 10 cm, width: 10 cm) of the resulting oxygen-absorbing multilayer sheet were put in the two gas barrier bags, respectively, together with 500 cc of air, respectively. The relative humidity of one of the bags was adjusted to be 100%, and that of the other bag was adjusted to be 30%. Both bags were sealed and were stored in an atmosphere of a temperature of 40? C. for 30 days. The total amount of oxygen absorbed during the storage was measured. (2) Odor of Oxygen-Absorbing Multilayer Sheet after Oxygen Absorption

(18) Sealed bags stored at a temperature of 40? C. and a relative humidity of 100% for 30 days, as in the measurement of the amount of oxygen absorbed, were opened, and the odor in each bag was verified.

(19) The odor was evaluated for whether the sheet itself has an odor or not and for whether the odor changed or not after oxygen absorption. When the sheet itself had no odor and when the odor did not change after oxygen absorption, the sheet was considered no odor after oxygen absorption. (3) Oxygen Transmission Rate of Oxygen-Absorbing Multilayer Sheet

(20) The oxygen transmission rate was measured on the 30th day from the start of the measurement in an atmosphere of a temperature of 23? C. and a relative humidity of 60% with an oxygen transmission rate measurement apparatus (OX-TRAN 2-61, manufactured by MOCON, Inc.). A lower measurement value indicates a higher oxygen barrier property. The oxygen transmission rate was measured in accordance with ASTM D3985.

Example 1-2

(21) An oxygen-absorbing multilayer sheet was formed as in Example 1-1 except that diester compound B was used instead of diester compound A and was evaluated as in Example 1-1.

Example 1-3

(22) An oxygen-absorbing multilayer sheet was formed as in Example 1-1 except that diester compound C was used instead of diester compound A and was evaluated as in Example 1-1.

Example 1-4

(23) An oxygen-absorbing multilayer sheet was formed as in Example 1-1 except that diester compound D was used instead of diester compound A and was evaluated as in Example 1-1.

Example 1-5

(24) An oxygen-absorbing multilayer sheet was formed as in Example 1-1 except that diamide compound E was used instead of diester compound A and was evaluated as in Example 1-1.

Example 1-6

(25) An oxygen-absorbing multilayer sheet was formed as in Example 1-1 except that acid anhydride F was used instead of diester compound A and was evaluated as in Example 1-1.

Comparative Example 1-1

(26) A multilayer sheet was formed as in Example 1-1 except that diester compound A and cobalt(II) stearate were not used and was evaluated as in Example 1-1.

Comparative Example 1-2

(27) A multilayer sheet was formed as in Example 1-1 except that diester compound A was not used and was evaluated as in Example 1-1.

Comparative Example 1-3

(28) A multilayer sheet was formed as in Example 1-1 except that cobalt(II) stearate was not used and was evaluated as in Example 1-1.

(29) The following table shows the conditions and results of each Example and each Comparative Example.

(30) TABLE-US-00002 TABLE 2 Oxygen-absorbing layer composition Amount of oxygen absorbed.sup.1) (parts by mass) (cc/200 cm.sup.2) Odor after Oxygen Thermoplastic Compound having Transition Relative Relative oxygen transmission rate.sup.3) resin tetralin ring metal humidity 100% humidity 30% absorption.sup.2) (cc/m.sup.2 .Math. day .Math. atm) Example 1-1 EVOH Diester compound A Co 5.6 1.5 No 0.01 (95) (5) (0.05) Example 1-2 EVOH Diester compound B Co 5.2 1.4 No 0.02 (95) (5) (0.05) Example 1-3 EVOH Diester compound C Co 5.3 1.5 No 0.01 (95) (5) (0.05) Example 1-4 EVOH Diester compound D Co 5.8 1.6 No 0.01 (95) (5) (0.05) Example 1-5 EVOH Diamide compound E Co 3.4 0.9 No 0.04 (95) (5) (0.05) Example 1-6 EVOH Acid anhydride F Co 4.3 1.0 No 0.03 (95) (5) (0.05) Comparative EVOH 0 0 No 0.1 Example 1-1 (100) Comparative EVOH Co 0 0 No 0.1 Example 1-2 (100) (0.05) Comparative EVOH Diester compound A 0 0 No 0.1 Example 1-3 (95) (5) .sup.1)Total amount of oxygen absorbed for 30 days from the start of test at 40? C. .sup.2)Odor after storage for 30 days at 40? C. and a relative humidity of 100% .sup.3)Measured at 23? C. and a relative humidity of 60%

(31) As obvious from the table, the oxygen-absorbing multilayer sheets of the Examples absorbed oxygen by the oxygen-absorbing layers and could reduce the oxygen transmission rates, compared to those in the Comparative Examples. It was also observed that the oxygen-absorbing multilayer sheets of the Examples not only did not have any odor by themselves but also did not have any odor after oxygen absorption.

Example 1-7

(32) 95 parts by mass of polyethylene terephthalate (product name: 1101E, also abbreviated to PET, manufactured by Invista), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 260? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(33) An oxygen-absorbing multilayer sheet was formed with a two-material three-layer multilayer sheet molding apparatus equipped with first to third extruders, a feed block, a T-die, a cooling roll, and a sheet take-up unit by extruding polyethylene terephthalate from the first and third extruders and the oxygen-absorbing composition prepared above from the second extruder and supplying the extrudates to the feed block. The multilayer sheet had a layer structure composed of PET (100 ?m)/oxygen-absorbing layer (300 ?m)/PET (100 ?m).

(34) The oxygen transmission rate of the resulting oxygen-absorbing multilayer sheet was measured in an atmosphere of a temperature of 23? C. and a relative humidity of 60% or 90%. The oxygen transmission rate 30 days after the start of the measurement is shown in Table 3. The oxygen transmission rate was measured with an oxygen transmission rate measurement apparatus as in Example 1-1. The odor of the multilayer sheet after the measurement of the oxygen transmission rate was verified as in Example 1-1.

Example 1-8

(35) An oxygen-absorbing multilayer sheet was formed as in Example 1-7 except that diester compound B was used instead of diester compound A and was evaluated as in Example 1-7.

Example 1-9

(36) An oxygen-absorbing multilayer sheet was formed as in Example 1-7 except that diester compound C was used instead of diester compound A and was evaluated as in Example 1-7.

Example 1-10

(37) An oxygen-absorbing multilayer sheet was formed as in Example 1-7 except that diester compound D was used instead of diester compound A and was evaluated as in Example 1-7.

Example 1-11

(38) An oxygen-absorbing multilayer sheet was formed as in Example 1-7 except that diester compound E was used instead of diester compound A and was evaluated as in Example 1-7.

Comparative Example 1-4

(39) A multilayer sheet was formed as in Example 1-7 except that diester compound A and cobalt(II) stearate were not used and was evaluated as in Example 1-7.

Comparative Example 1-5

(40) A multilayer sheet was formed as in Example 1-7 except that diester compound A was not used and was evaluated as in Example 1-7.

Comparative Example 6

(41) A multilayer sheet was formed as in Example 1-7 except that cobalt(II) stearate was not used and was evaluated as in Example 1-7.

(42) TABLE-US-00003 TABLE 3 Oxygen-absorbing layer composition Oxygen transmission rate Odor after measurement of (parts by mass) (cc/m.sup.2 .Math. day .Math. atm) oxygen transmission rate Thermoplastic Compound having Transition Relative Relative Relative Relative resin tetralin ring metal humidity 60% humidity 90% humidity 60% humidity 90% Example 1-7 PET Diester compound A Co 4.2 4.0 No No (95) (5) (0.05) Example 1-8 PET Diester compound B Co 4.8 5.0 No No (95) (5) (0.05) Example 1-9 PET Diester compound C Co 4.2 4.2 No No (95) (5) (0.05) Example 1-10 PET Diester compound D Co 4.0 4.0 No No (95) (5) (0.05) Example 1-11 PET Diamide compound E Co 5.6 5.8 No No (95) (5) (0.05) Comparative PET 7.5 7.6 No No Example 1-4 (100) Comparative PET Co 7.6 7.4 No No Example 1-5 (100) (0.05) Comparative PET Diester compound A 7.6 7.5 No No Example 1-6 (95) (5) .sup.1)Measured at 23? C.

(43) As obvious from the table, the oxygen-absorbing multilayer sheets of the Examples absorbed oxygen by the oxygen-absorbing layers and could reduce the oxygen transmission rates, compared to those in the Comparative Examples. It was also observed that the oxygen-absorbing multilayer sheets of the Examples not only did not have any odor by themselves but also did not have any odor after oxygen absorption.

Example 1-12

(44) 95 parts by mass of polyamide 6 (product name: UBE nylon 1024B, hereinafter also abbreviated to PA6, manufactured by Ube Industries, Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 250? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(45) An oxygen-absorbing multilayer film was formed with a two-material three-layer multilayer film molding apparatus equipped with two extruders, a feed block, a T-die, a cooling roll, and a sheet take-up unit by extruding PA6 from the first extruder and the oxygen-absorbing composition prepared above from the second extruder and supplying the extrudates to the feed block. The multilayer sheet had a layer structure composed of PA6 (90 ?m)/oxygen-absorbing layer (180 ?m)/PA6 (90 ?m). The resulting multilayer film was stretched three times in the MD and three times in the TD at an elongation temperature of 80? C. with a batch-type biaxial stretching apparatus (manufactured by Toyo Seiki Co., Ltd., center stretch-type biaxial stretching apparatus) and was thermally fixed at 210? C. for 30 seconds to obtain a biaxial stretched film. The thicknesses of the individual layers after stretching were 10/20/10 (?m).

(46) The oxygen transmission rate of the resulting oxygen-absorbing multilayer film was measured in an atmosphere of a temperature of 23? C. and a relative humidity of 60%. The oxygen transmission rate 30 days after the start of the measurement is shown in Table 4. The oxygen transmission rate was measured with an oxygen transmission rate measurement apparatus as in Example 1-1. The odor of the multilayer film after the measurement of the oxygen transmission rate was verified as in Example 1-1.

Example 1-13

(47) An oxygen-absorbing multilayer film was formed as in Example 1-12 except that diester compound B was used instead of diester compound A and was evaluated as in Example 1-12.

Example 1-14

(48) An oxygen-absorbing multilayer film was formed as in Example 1-12 except that diester compound C was used instead of diester compound A and was evaluated as in Example 1-12.

Example 1-15

(49) An oxygen-absorbing multilayer film was formed as in Example 1-12 except that diester compound D was used instead of diester compound A and was evaluated as in Example 1-12.

Example 1-16

(50) An oxygen-absorbing multilayer film was formed as in Example 1-12 except that diamide compound E was used instead of diester compound A and was evaluated as in Example 1-12.

Example 1-17

(51) An oxygen-absorbing multilayer film was formed as in Example 1-12 except that the amount of the polyamide compound was 90 parts by mass and that the amount of diamide compound E was 10 parts by mass and was evaluated as in Example 1-12.

Comparative Example 1-7

(52) A multilayer film was formed as in Example 1-12 except that diester compound A and cobalt(II) stearate were not used and was evaluated as in Example 1-12.

Comparative Example 1-8

(53) A multilayer film was formed as in Example 1-12 except that diester compound A was not used and was evaluated as in Example 1-12.

Comparative Example 1-9

(54) A multilayer film was formed as in Example 1-12 except that cobalt(II) stearate was not used and was evaluated as in Example 1-12.

(55) The following table shows the conditions and the evaluation results of the Examples and the Comparative Examples.

(56) TABLE-US-00004 TABLE 4 Oxygen-absorbing layer composition Oxygen Odor after (parts by mass) transmission measurement Thermoplastic Compound having Transition rate.sup.1) of oxygen resin tetralin ring metal (cc/m.sup.2 .Math. day .Math. atm) transmission rate Example 1-12 Polyamide 6 Diester compound A Co 15 No (95) (5) (0.05) Example 1-13 Polyamide 6 Diester compound B Co 16 No (95) (5) (0.05) Example 1-14 Polyamide 6 Diester compound C Co 15 No (95) (5) (0.05) Example 1-15 Polyamide 6 Diester compound D Co 13 No (95) (5) (0.05) Example 1-16 Polyamide 6 Diamide compound E Co 17 No (95) (5) (0.05) Example 1-17 Polyamide 6 Diamide compound E Co 15 No (90) (10) (0.05) Comparative Polyamide 6 21 No Example 1-7 (100) Comparative Polyamide 6 Co 20 No Example 1-8 (100) (0.05) Comparative Polyamide 6 Diester compound A 21 No Example 1-9 (95) (5) .sup.1)Measured at 23? C. and a relative humidity of 60%

(57) As obvious from the table, the oxygen-absorbing multilayer films of the Examples absorbed oxygen by the oxygen-absorbing layers and could reduce the oxygen transmission rates, compared to those in the Comparative Examples. It was also observed that the oxygen-absorbing multilayer films of the Examples not only did not have any odor by themselves but also did not have any odor after oxygen absorption.

Example 1-18

(58) 95 parts by mass of a linear low-density polyethylene (product name: UMERIT 140HK, hereinafter also abbreviated to LLDPE1, manufactured by Ube-Maruzen Polyethylene Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 200? C., extruded into a strand from the extruder head, cooled, and was then pelletized to obtain an oxygen-absorbing composition.

(59) A two-material three-layer film was formed with a two-material three-layer multilayer film molding apparatus equipped with two extruders, a feed block, a T-die, a cooling roll, a corona discharge unit, a winding unit, and other equipment by extruding linear low-density polyethylene (product name: ELITE 5220G, hereinafter also abbreviated to LLDPE2, manufactured by The Dow Chemical Company) from the first extruder and the oxygen-absorbing composition prepared above from the second extruder and supplying the extrudates to the feed block. The surface of one of the LLDPE2 layers was treated with corona discharge at a rate of 60 m/min to produce a film roll. The multilayer film had a layer structure composed of LLDPE2 (20 ?m)/oxygen-absorbing layer (40 ?m)/LLDPE2 (20 ?m).

(60) Subsequently, on the corona treated surface, nylon 6 film (product name: N1202, manufactured by Toyobo Co., Ltd.) and alumina-deposited PET film (product name: GL-ARH-F, manufactured by Toppan Printing Co., Ltd.) were dry-laminated using a urethane-based dry-lamination adhesive (product name: TM251/CAT-RT88, manufactured by Toyo-Morton, Ltd.) to prepare a transparent oxygen-absorbing multilayer film of an oxygen-absorbing multilayer body composed of alumina-deposited PET film (12 ?m)/urethane-based dry-lamination adhesive (3 ?m)/nylon 6 film (15 ?m)/urethane-based dry-lamination adhesive (3 ?m)/LLDPE2 (20 ?m)/oxygen-absorbing layer (40 ?m)/LLDPE2 (20 ?m). The resulting oxygen-absorbing multilayer film was evaluated as follows. (1) Amount of Oxygen Absorbed by Oxygen-Absorbing Multilayer Film

(61) Two gas barrier bags made of an aluminum foil laminate film were prepared. Two test pieces (length: 10 cm, width: 10 cm) of the resulting oxygen-absorbing multilayer film were put in the two gas barrier bags, respectively, together with 500 cc of air. The relative humidity of one of the bags was adjusted to be 100%, and that of the other bag was adjusted to be 30%. Both bags were sealed and were stored in an atmosphere of a temperature of 40? C. for 30 days. The total amount of oxygen absorbed during the storage was measured. (2) Odor of Oxygen-Absorbing Multilayer Film after Oxygen Absorption

(62) The sealed bags after the measurement of the amount of oxygen absorbed were opened, and the odor in the bags was verified. (3) Sealing Strength

(63) The resulting oxygen-absorbing multilayer film was formed into a three-side sealed bag of 10 cm?18 cm such that the LLDPE2 layer was the inside surface. The bag was stored at a temperature of 40? C. and a relative humidity of 90% for 100 days, and the sealing strength of the bag was then measured. In the measurement of the sealing strength, the sealing strength of the short side portion of the three-side sealed bag was measured in accordance with JIS 20238.

Example 1-19

(64) An oxygen-absorbing multilayer film was formed as in Example 1-18 except that diester compound B was used instead of diester compound A. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Example 1-20

(65) An oxygen-absorbing multilayer film was formed as in Example 1-18 except that diester compound C was used instead of diester compound A. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Example 1-21

(66) An oxygen-absorbing multilayer film was formed as in Example 1-18 except that diester compound D was used instead of diester compound A. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Example 1-22

(67) An oxygen-absorbing multilayer film was formed as in Example 1-18 except that diamide compound E was used instead of diester compound A. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Example 1-23

(68) An oxygen-absorbing multilayer film was formed as in Example 1-18 except that acid anhydride F was used instead of diester compound A. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Comparative Example 1-10

(69) A multilayer film was formed as in Example 1-18 except that diester compound A and cobalt(II) stearate were not used. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Comparative Example 1-11

(70) A multilayer film was formed as in Example 1-18 except that diester compound A was not used. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Comparative Example 1-12

(71) A multilayer film was formed as in Example 1-18 except that cobalt(II) stearate was not used. Subsequently, measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of the bag were performed as in Example 1-18.

Comparative Example 1-13

(72) An iron powder having an average particle diameter of 30 ?m and calcium chloride were mixed at a mass ratio of 100:1. The mixture and LLDPE1 were kneaded at a mass ratio of 30:70 to prepare an iron-based oxygen-absorbing composition. A two-material three-layer film was tried to be formed as in Example 1-18 except that this iron-based oxygen-absorbing composition was used instead of the oxygen-absorbing composition in Example 1-18, but the film did not have a smooth surface that can withstand the subsequent studies because of the generation of the irregularity of the film surface due to the iron powder. Accordingly, the iron-based oxygen-absorbing composition was extruded to be laminated to form an oxygen-absorbing layer having a thickness of 40 ?m on a linear low-density polyethylene film (product name: Tohcello T.U.X HC, hereinafter referred to as LLDPE3, manufactured by Tohcello Inc.) having a thickness of 50 ?m, and the surface of the iron-based oxygen-absorbing composition layer was then treated with corona discharge at a rate of 60 m/min to obtain a laminate film.

(73) Subsequently, on the corona treated surface of the laminate film, the layers shown below were dry-laminated as in Example 1-18 to form an iron-based oxygen-absorbing multilayer film composed of alumina-deposited PET film (12 ?m)/urethane-based dry-lamination adhesive (3 ?m)/nylon 6 film (15 ?m)/urethane-based dry-lamination adhesive (3 ?m)/oxygen-absorbing layer (40 ?m)/LLDPE3 (50 ?m). The resulting iron-based oxygen-absorbing multilayer film was opaque because of the presence of iron.

(74) Subsequently, the resulting iron-based oxygen-absorbing multilayer film was subjected to measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of a bag as in Example 1-18.

Comparative Example 1-14

(75) 100 parts by mass of nylon MXD6 (product name: MX nylon S6011, hereinafter also abbreviated to N-MXD6, manufactured by Mitsubishi Gas Chemical Company, Inc.) and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 260? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(76) A three-material five-layer film was formed with a three-material five-layer multilayer film molding apparatus equipped with three extruders, a feed block, a T-die, a cooling roll, a corona discharge unit, a winding unit, and other equipment by extruding LLDPE2 from the first extruder, the oxygen-absorbing composition prepared above from the second extruder, and adhesive polyethylene (product name: MODIC M545, hereinafter also abbreviated to adhesive PE, manufactured by Mitsubishi Chemical Corporation) from the third extruder and supplying the extrudates to the feed block. The surface of one of the LLDPE2 layers was treated with corona discharge at a rate of 60 m/min to produce a film roll. The multilayer film had a layer structure composed of LLDPE2 (10 ?m)/adhesive PE (10 ?m)/oxygen-absorbing layer (40 ?m)/adhesive PE (10 ?m)/LLDPE2 (10 ?m).

(77) Subsequently, on the corona treated surface of the laminate film, the layers shown below were dry-laminated as in Example 1-18 to prepare a nylon MXD6-based oxygen-absorbing multilayer film composed of alumina-deposited PET film (12 ?m)/urethane-based dry-lamination adhesive (3 ?m)/nylon 6 film (15 ?m)/urethane-based dry-lamination adhesive (3 ?m)/LLDPE2 (10 ?m)/adhesive PE (10 ?m)/oxygen-absorbing layer (40 ?m)/adhesive PE (10 ?m)/LLDPE2 (10 ?m).

(78) Subsequently, the resulting nylon MXD6-based oxygen-absorbing multilayer film was subjected to measurement of the amount of oxygen absorbed, verification of the odor after oxygen absorption, and measurement of the sealing strength of a bag as in Example 1-18.

(79) The following table shows the conditions and results of the Examples and the Comparative Examples.

(80) TABLE-US-00005 TABLE 5 Amount of oxygen absorbed.sup.1) Odor after Oxygen-absorbing layer composition (cc/200 cm.sup.2) oxygen absorption.sup.1) Sealing strength.sup.3) (parts by mass) Relative Relative Relative Relative (kg/15 mm) Thermoplastic Compound having Transition humidity humidity humidity humidity After resin tetralin ring metal 100% 30% 100% 30% Initial storage Example 1-18 LLDPE Diester compound A Co 5.8 1.5 No No 7.3 7.4 (95) (5) (0.05) Example 1-19 LLDPE Diester compound B Co 5.4 1.4 No No 7.5 7.4 (95) (5) (0.05) Example 1-20 LLDPE Diester compound C Co 5.4 1.5 No No 7.6 7.5 (95) (5) (0.05) Example 1-21 LLDPE Diester compound D Co 6.0 1.6 No No 7.4 7.6 (95) (5) (0.05) Example 1-22 LLDPE Diamide compound E Co 4.0 0.9 No No 7.5 7.5 (95) (5) (0.05) Example 1-23 LLDPE Acid anhydride F Co 4.8 1.0 No No 7.6 7.4 (95) (5) (0.05) Comparative LLDPE 0 0 No No 7.4 7.5 Example 1-10 (100) Comparative LLDPE Co 0 0 No No 7.3 7.4 Example 1-11 (100) (0.05) Comparative LLDPE Diester compound A 0 0 No No 7.4 7.4 Example 1-12 (95) (5) Comparative Iron-based oxygen absorber + LLDPE 31.7 0.5 Slight iron Slight iron 7.2 7.2 Example 1-13 odor odor Comparative N-MXD6 Co 6.0 0.4 No No 7.1 0.8 Example 1-14 (100) (0.05) .sup.1)Total amount of oxygen absorbed for 30 days from the start of test at 40? C. .sup.2)Examined by opening sealed bag after measurement of oxygen absorption .sup.3)Storage at 40? C. and a relative humidity of 90% for 100 days

(81) As obvious from the table, it was at least observed that the oxygen-absorbing multilayer films of the Examples exhibited oxygen-absorbing properties under high humidity and under low humidity, no odor was generated even after oxygen absorption, and the sealing strength was maintained even after oxygen absorption.

Second Experiment

(82) Diester compounds A to D each having a tetralin ring produced in Synthesis Examples 1 to 4, diamide compound E having a tetralin ring produced in Synthesis Example 5, and acid anhydride F having a tetralin ring produced in Synthesis Example 6 were used.

Example 2-1

(83) (Production of Oxygen-Absorbing Composition)

(84) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL SP521B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(85) (Production of Oxygen-Absorbing Multilayer Film)

(86) An oxygen-absorbing monolayer film being an oxygen-absorbing composition in a film form having a width of 800 mm and a thickness of 15 ?m was formed from the resulting oxygen-absorbing composition with a twin-screw extruder having two 96-mm diameter screws at conditions of an extrusion temperature of 210? C., a screw rotation number of 60 rpm, a feed screw rotation number of 20 rpm, and a taking-up speed of 50 m/min.

(87) The resulting oxygen-absorbing monolayer film was treated with corona discharge at a rate of 100 m/min to produce a film roll. The resulting film roll was observed to have no thickness deviation such as bumps and to have a satisfactory appearance. Subsequently, a nylon film (product name: N1130, manufactured by Toyobo Co., Ltd.) was dry-laminated on the corona treated surface using a urethane-based dry-lamination adhesive (product name: AD817/CAT-RT86L-60, manufactured by Toyo-Morton, Ltd.). The EVOH surface of the resulting laminate was further treated with corona discharge at a rate of 100 m/min to produce a film roll. The resulting film roll had a satisfactory appearance without thickness deviation such as bumps. An LLDPE film (product name: L6100, manufactured by Toyobo Co., Ltd.) was dry-laminated on the corona treated surface using a urethane-based dry-lamination adhesive (product name: AD817/CAT-RT86L-60, manufactured by Toyo-Morton, Ltd.) to obtain an oxygen-absorbing multilayer film composed of nylon film (15 ?m)/adhesive (3 ?m)/oxygen-absorbing monolayer film (15 ?m)/adhesive (3 ?m)/LLDPE film (50 ?m). The numeric characters shown with a unit of ?m in the parentheses refer to the thickness. The same applies to the following Examples unless specifically indicated otherwise.

(88) (Production of Oxygen-Absorbing Multilayer Sheet)

(89) An oxygen-absorbing multilayer sheet was formed with a three-material five-layer multilayer sheet molding apparatus equipped with first to third extruders, a feed block, a T-die, a cooling roll, and a sheet take-up unit by extruding polypropylene (product name: NOVATEC PP FY6C, hereinafter also abbreviated to PP1, manufactured by Japan Polypropylene Corporation) from the first extruder, the oxygen-absorbing composition from the second extruder, and adhesive polypropylene (product name: MODIC P604V, hereinafter also abbreviated to adhesive PP, manufactured by Mitsubishi Chemical Corporation) from the third extruder and supplying the extrudates to the feed block. The multilayer sheet had a layer structure composed of PP1 (400 ?m)/adhesive PP (15 ?m)/oxygen-absorbing layer (100 ?m)/adhesive PP (15 ?m)/PP1 (400 ?m) from the inner layer.

(90) (Production of oxygen-absorbing multilayer container)

(91) The resulting oxygen-absorbing multilayer sheet was thermoformed into a tray-shaped oxygen-absorbing multilayer container having an internal volume of 400 cc and a surface area of 200 cm.sup.2 with a vacuum molding apparatus equipped with a plug assist. The resulting oxygen-absorbing multilayer container was filled with 10 g of a humidity conditioning agent to adjust the relative humidity inside the container to 100%. Subsequently, the container was sealed by joining by heat sealing using a gas barrier film (product name: EVAL EFCR-15, manufactured by Kuraray Co., Ltd.) as the lid member, while adjusting the initial oxygen concentration to 2 vol % by nitrogen purge to obtain an oxygen-absorbing sealed container. The heat sealing was performed with a pack-sealing apparatus manufactured by Eshin Pack Industry Co., Ltd. at a heat-sealing temperature of 240? C. for heat sealing time of 2 sec at a heat sealing pressure of 0.3 MPa.

(92) The resulting oxygen-absorbing multilayer film, oxygen-absorbing multilayer sheet, and oxygen-absorbing multilayer container were evaluated as follows. (1) Amount of Oxygen Absorbed by Oxygen-Absorbing Multilayer Film

(93) Two gas barrier bags made of an aluminum foil laminate film were prepared. Two test pieces (length: 10 cm, width: 10 cm) of the resulting oxygen-absorbing multilayer film were put in the two gas barrier bags, respectively, together with 500 cc of air. The relative humidity of one of the bags was adjusted to be 100%, and that of the other bag was adjusted to be 30%. Both bags were sealed and were stored at 40? C. for 30 days. The total amount of oxygen absorbed during the storage was measured. (2) Oxygen Transmission Rate of Oxygen-Absorbing Multilayer Film

(94) The oxygen transmission rate was measured on the 30th day from the start of the measurement in an atmosphere of a temperature of 23? C. and a relative humidity of 90% with an oxygen transmission rate measurement apparatus (OX-TRAN 2-61, manufactured by MOCON, Inc.). A lower measurement value indicates a higher oxygen barrier property. (3) Amount of Oxygen Absorbed by Oxygen-Absorbing Multilayer Sheet

(95) Two gas barrier bags made of an aluminum foil laminate film were prepared. Two test pieces (length: 10 cm, width: 10 cm) of the resulting oxygen-absorbing multilayer sheet were put in the two gas barrier bags, respectively, together with 500 cc of air. The relative humidity of one of the bags was adjusted to be 100%, and that of the other bag was adjusted to be 30%. Both bags were sealed and were stored at 40? C. for 30 days. The total amount of oxygen absorbed during the storage was measured. (4) Odor of Oxygen-Absorbing Multilayer Sheet after Oxygen Absorption

(96) As in the measurement of the amount of oxygen absorbed by oxygen-absorbing multilayer sheet, a sealed bag stored at a temperature of 40? C. and a relative humidity of 100% for 30 days was opened, and the odor in the bags were verified. (5) Oxygen Transmission Rate of Oxygen-Absorbing Multilayer Container

(97) The oxygen transmission rate was measured on the 30th day from the start of the measurement in an atmosphere of a temperature of 23? C. and relative humidities of 100% (inside the container) and 50% (outside the container) with an oxygen transmission rate measurement apparatus (OX-TRAN 2-61, manufactured by MOCON, Inc.). A lower measurement value indicates a higher oxygen barrier property. The detection lower limit is an oxygen transmission rate of 5?10.sup.?5 cc/(package.Math.day.Math.0.21 atm).

Example 2-2

(98) An oxygen-absorbing multilayer film, an oxygen-absorbing multilayer sheet, and an oxygen-absorbing multilayer container were produced as in Example 2-1 except that diester compound B was used instead of diester compound A and were evaluated as in Example 2-1.

Example 2-3

(99) An oxygen-absorbing multilayer film, an oxygen-absorbing multilayer sheet, and an oxygen-absorbing multilayer container were produced as in Example 2-1 except that diester compound C was used instead of diester compound A and were evaluated as in Example 2-1.

Example 2-4

(100) An oxygen-absorbing multilayer film, an oxygen-absorbing multilayer sheet, and an oxygen-absorbing multilayer container were produced as in Example 2-1 except that diester compound D was used instead of diester compound A and were evaluated as in Example 2-1.

Example 2-5

(101) An oxygen-absorbing multilayer film, an oxygen-absorbing multilayer sheet, and an oxygen-absorbing multilayer container were produced as in Example 2-1 except that diamide compound E was used instead of diester compound A and were evaluated as in Example 2-1.

Example 2-6

(102) An oxygen-absorbing multilayer film, an oxygen-absorbing multilayer sheet, and an oxygen-absorbing multilayer container were produced as in Example 2-1 except that acid anhydride F was used instead of diester compound A and were evaluated as in Example 2-1.

Comparative Example 2-1

(103) Oxygen-absorbing multilayer film, multilayer sheet, and multilayer container were prepared as in Example 2-1 except that diester compound A was not used and were evaluated as in Example 2-1.

(104) The following table shows the conditions and results of the Examples and the Comparative Examples.

(105) TABLE-US-00006 TABLE 6 Oxygen- Oxygen-absorbing Oxygen-absorbing absorbing multilayer film multilayer sheet multilayer Amount of oxygen Amount of oxygen container Oxygen-absorbing layer composition absorbed.sup.1) Oxygen absorbed.sup.1) Oxygen (parts by mass) (cc/200 cm.sup.2) transmission (cc/200 cm.sup.2) transmission Compound Relative Relative rate.sup.2) Relative Relative Odor after rate.sup.4).Math.5) Thermoplastic having Transition humidity humidity (cc/m.sup.2 .Math. humidity humidity oxygen (cc/package .Math. resin tetralin ring metal 100% 30% day .Math. atm) 100% 30% absorption.sup.3) day .Math. 0.21 atm) Example 2-1 95 5 0.05 7.0 1.8 1.5 ? 10.sup.?2 5.4 1.3 No Undetectable (EVOH) (Diester (Co) compound A) Example 2-2 95 5 0.05 6.5 1.5 1.7 ? 10.sup.?2 5.0 1.2 No Undetectable (EVOH) (Diester (Co) compound B) Example 2-3 95 5 0.05 4.2 1.2 2.0 ? 10.sup.?2 3.8 0.9 No Undetectable (EVOH) (Diester (Co) compound C) Example 2-4 95 5 0.05 10.8 2.7 1.2 ? 10.sup.?2 6.0 1.9 No Undetectable (EVOH) (Diester (Co) compound D) Example 2-5 95 5 0.05 4.4 1.0 2.3 ? 10.sup.?2 3.1 0.6 No Undetectable (EVOH) (Diamide (Co) compound E) Example 2-6 95 5 0.05 4.5 1.2 2.0 ? 10.sup.?2 3.6 0.8 No Undetectable (EVOH) (Acid (Co) anhydride F) Comparative 100 0 0 0.85 0 0 No 6.0 ? 10.sup.?4 Example 2-1 (EVOH) .sup.1)Stored for 30 days at a temperature of 40? C. and a relative humidity of 100% or 30% .sup.2)Stored for 30 days in an atmosphere of a temperature of 23? C. and a relative humidity of 90% .sup.3)Stored for 30 days in an atmosphere of a temperature of 40? C. and a relative humidity of 100% .sup.4)Stored for 30 days in an atmosphere of a temperature of 23? C. and a relative humidity of 100% .sup.5)Detection lower limit: 5 ? 10.sup.?5 cc/package .Math. day/0.21 atm

(106) As obvious from the table, it was observed that the oxygen-absorbing multilayer sheets and oxygen-absorbing multilayer containers of the Examples exhibited oxygen-absorbing properties; the oxygen transmission rate could be reduced compared to that in Comparative Example 1-1; and no odor was generated even after oxygen absorption.

Third Experiment

(107) Diester compounds A to D each having a tetralin ring produced in Synthesis Examples 1 to 4, diamide compound E having a tetralin ring produced in Synthesis Example 5, and acid anhydride F having a tetralin ring produced in Synthesis Example 6 were used.

Example 3-1

(108) 95 parts by mass of a linear low-density polyethylene (product name: UMERIT 140HK, hereinafter referred to as LLDPE1, manufactured by Ube-Maruzen Polyethylene Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 200? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain oxygen-absorbing composition A.

(109) A two-material two-layer film (thickness: oxygen-absorbing layer: 30 ?m/sealant layer: 30 ?m) having a width of 900 mm was formed with a multilayer film molding apparatus equipped with two extruders, a feed block, a T-die, a cooling roll, a corona discharge unit, a winding unit, and other equipment by extruding linear low-density polyethylene, a material for sealant layer, (product name: NOVATEC LL UF641, hereinafter referred to as LLDPE2, manufactured by Japan Polyethylene Corporation) from the first extruder and oxygen-absorbing composition A, a material for oxygen-absorbing layer, from the second extruder and supplying the extrudates to the feed block. Subsequently, the surface of the oxygen-absorbing layer was treated with corona discharge at a rate of 60 m/min to produce a film roll.

(110) Subsequently, on the corona treated surface, nylon 6 film (product name: N1202, manufactured by Toyobo Co., Ltd.) and alumina-deposited PET film (product name: GL-ARH-F, manufactured by Toppan Printing Co., Ltd.) were dry-laminated using a urethane-based dry-lamination adhesive (product name: TM251/CAT-RT88, manufactured by Toyo-Morton, Ltd.) to prepare an oxygen-absorbing multilayer film of an oxygen-absorbing multilayer body composed of alumina-deposited PET film (12 ?m)/urethane-based dry-lamination adhesive (3 ?m)/nylon 6 film (15 ?m)/urethane-based dry-lamination adhesive (3 ?m)/oxygen-absorbing layer (30 ?m)/LLDPE2 (30 ?m). The numeric characters shown with a unit of ?m in the parentheses refer to the thickness.

(111) The resulting oxygen-absorbing multilayer film was formed into a three-side sealed bag of 13 cm?18 cm such that the LLDPE2 layer was the inside surface. The bag was filled with 10 g of a humidity conditioning agent to adjust the relative humidity in the bag to 100% or 30%. Subsequently, the bag was filled with 50 cc of a gas having an initial oxygen concentration adjusted to 2 vol % by nitrogen purge and was sealed. The thus-prepared sealed bag was stored at 23? C. The oxygen concentration inside the bag was measured after storage for one month. The sealed bag stored for one month was opened, and the odor therein was verified. In addition, the sealing strength of the bag was measured before and after the storage for one month. The measurement of the sealing strength was performed for the short side portion of the three-side sealed bag in accordance with JIS Z0238.

Example 3-2

(112) An oxygen-absorbing multilayer film was formed as in Example 3-1 except that diester compound B was used instead of diester compound A. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Example 3-3

(113) An oxygen-absorbing multilayer film was formed as in Example 3-1 except that diester compound C was used instead of diester compound A. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Example 3-4

(114) An oxygen-absorbing multilayer film was formed as in Example 3-1 except that diester compound D was used instead of diester compound A. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Example 3-5

(115) An oxygen-absorbing multilayer film was formed as in Example 3-1 except that diamide compound E was used instead of diester compound A. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Example 3-6

(116) An oxygen-absorbing multilayer film was formed as in Example 3-1 except that acid anhydride F was used instead of diester compound A. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Comparative Example 3-1

(117) A multilayer film was formed as in Example 3-1 except that diester compound A and cobalt stearate were not used. A sealed bag was then produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Comparative Example 3-2

(118) A multilayer film was formed as in Example 3-1 except that cobalt stearate was not used. A sealed bag was then produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Comparative Example 3-3

(119) A multilayer film was formed as in Example 3-1 except that diester compound A was not used. A sealed bag was then produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Comparative Example 3-4

(120) An iron powder having an average particle diameter of 30 ?m and calcium chloride were mixed at a mass ratio of 100:1. The mixture and LLDPE1 were kneaded at a mass ratio of 30:70 to obtain an iron-based oxygen-absorbing composition. A two-material two-layer film was tried to be formed as in Example 3-1 except that this iron-based oxygen-absorbing composition was used instead of oxygen-absorbing composition (1), but the film did not have a smooth surface that can withstand the subsequent studies because of the irregularity of the film surface due to the iron powder.

Comparative Example 3-5

(121) A laminate film composed of oxygen-absorbing layer (30 ?m)/linear low-density polyethylene film (50 ?m) was formed by extrusion lamination of an oxygen-absorbing layer having a thickness of 30 ?m of the iron-based oxygen-absorbing composition prepared in Comparative Example 3-4 to a linear low-density polyethylene film (product name: T.U.X HC, manufactured by Mitsui Chemical Tohocello, Inc.) having a thickness of 50 ?m. Subsequently, the surface of the oxygen-absorbing layer was treated with corona discharge. An oxygen-absorbing multilayer film was prepared by dry lamination as in Example 3-1 except that this laminate film was used instead of the oxygen-absorbing multilayer film having the two-material two-layer structure. Subsequently, a sealed bag was produced as in Example 3-1, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

Comparative Example 3-6

(122) 100 parts by mass of nylon MXD6 (product name: MX nylon S6011, hereinafter also abbreviated to N-MXD6, manufactured by Mitsubishi Gas Chemical Company, Inc.) and cobalt(II) stearate giving 0.05 parts by mass of cobalt was melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 260? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(123) A three-material three-layer film was formed with a three-material five-layer multilayer film molding apparatus equipped with three extruders, a feed block, a T-die, a cooling roll, a corona discharge unit, a winding unit, and other equipment by extruding LLDPE2 from the first extruder, the oxygen-absorbing composition prepared above from the second extruder, and adhesive polyethylene (product name: MODIC M545, hereinafter also abbreviated to adhesive PE, manufactured by Mitsubishi Chemical Corporation) from the third extruder and supplying the extrudates to the feed block. The surface of the oxygen-absorbing layer was treated with corona discharge at a rate of 60 m/min to produce a film roll. The multilayer film had a layer structure composed of oxygen-absorbing layer (30 ?m)/adhesive PE (10 ?m)/LLDPE (20 ?m).

(124) Subsequently, on the corona treated surface of the laminate film, the layers shown below were dry-laminated as in Example 3-1 to prepare a nylon MXD6-based oxygen-absorbing multilayer film composed of alumina-deposited PET film (12 ?m)/urethane-based dry-lamination adhesive (3 ?m)/nylon 6 film (15 ?m)/urethane-based dry-lamination adhesive (3 ?m)/oxygen-absorbing layer (30 ?m)/adhesive PE (10 ?m)/LLDPE (20 ?m).

(125) Subsequently, a sealed bag was produced as in Example 3-1 using the resulting nylon MXD6-based oxygen-absorbing multilayer film, and measurement of the oxygen concentration inside the bag, verification of odor after opening of the bag, and measurement of the sealing strength of the bag were performed as in Example 3-1.

(126) The following table shows the conditions and results of the Examples and the Comparative Examples.

(127) TABLE-US-00007 TABLE 7 Oxygen Oxygen-absorbing layer concentration Sealing strength composition/parts by mass (vol %).sup.1) Odor (kg/15 mm) Compound Relative Relative Relative Relative Relative Relative Thermoplastic having Transition humidity humidity humidity humidity humidity humidity resin tetralin ring metal 100% 30% Initial 100% 30% Initial 100% 30% Example 3-1 LLDPE Diester Co ?0.1 ?0.1 No No No 4.8 4.9 4.7 95 compound A 0.05 5 Example 3-2 LLDPE Diester Co 0.2 0.2 No No No 4.9 4.8 4.8 95 compound B 0.05 5 Example 3-3 LLDPE Diester Co ?0.1 ?0.1 No No No 4.8 4.7 4.9 95 compound C 0.05 5 Example 3-4 LLDPE Diester Co ?0.1 ?0.1 No No No 5.0 4.8 4.9 95 compound D 0.05 5 Example 3-5 LLDPE Diamide Co 0.3 0.4 No No No 4.8 4.9 4.8 95 compound E 0.05 5 Example 3-6 LLDPE Acid Co 0.2 0.1 No No No 4.9 5.0 4.8 95 anhydride F 0.05 5 Comparative LLDPE 2.1 2.0 No No No 4.9 4.8 4.9 Example 3-1 100 Comparative LLDPE Co 2.0 2.0 No No No 4.9 4.9 4.7 Example 3-2 100 0.05 Comparative LLDPE Diester 2.0 2.0 No No No 5.0 4.9 4.9 Example 3-3 100 compound A 5 Comparative LLDPE + iron ?0.1 1.8 Slight Slight Slight 5.5 5.4 5.3 Example 3-5 100 iron odor iron odor iron odor Comparative N-MXD6 Co ?0.1 1.9 No No No 5.5 2.2 5.3 Example 3-6 100 0.05 .sup.1)Initial oxygen concentration: 2.0%, amount of gas: 50 cc

(128) As obvious from the table, it was at least observed that the oxygen-absorbing multilayer bodies of the Examples exhibited satisfactory oxygen-absorbing performance under high humidity and under low humidity and no odor was generated and the sealing strength was maintained even after oxygen absorption.

Example 3-7

(129) One surface of a piece of paper having a basis weight of 400 g/m.sup.2 was treated with corona. A low-density polyethylene (product name: NOVATEC LD LD602A, hereinafter referred to as LDPE, manufactured by Japan Polyethylene Corporation) was extruded for lamination at a thickness of 30 ?m on the corona-treated surface of the paper with an extrusion laminator composed of an extruder, a T-die, a cooling roll, a corona treatment unit, and a winding unit. The other surface of the paper was then treated with corona to produce a laminate having a structure of LDPE layer/paper base.

(130) Subsequently, a molten multilayer was formed with a coextruding apparatus composed of first to fifth extruders, a feed block, a T-die, a cooling roll, and a winding unit by extruding LDPE from the first extruder, oxygen-absorbing composition A produced in Example 3-1 from the second extruder, adhesive polyethylene (product name: MODIC L504, hereinafter referred to as adhesive PE, manufactured by Mitsubishi Chemical Corporation) from the third extruder, nylon MXD6 (product name: MX nylon S6007, manufactured by Mitsubishi Gas Chemical Company, Inc.) from the fourth extruder, and LDPE from the fifth extruder and supplying the extrudates to the feed block to give a layer structure of LDPE (sealant) layer/oxygen-absorbing layer/adhesive PE layer/N-MXD6 layer/adhesive PE layer/LDPE layer in this order from the surface to be used as the inner side of a container. This molten multilayer was laminated by coextrusion to the paper base provided with LDPE by extrusion lamination in advance such that the molten multilayer was laminated on the corona-treated surface of the LDPE layer to obtain a paper base laminated material. The resulting laminated material had a structure composed of LDPE layer (10 ?m)/oxygen-absorbing layer (30 ?m)/adhesive PE layer (10 ?m)/N-MXD6 layer (10 ?m)/adhesive PE layer (10 ?m)/LDPE layer (10 ?m)/paper base/LDPE layer (30 ?m) in this order from the surface that was the inner side of a container.

(131) Subsequently, an anti-heat-sealing agent was applied to the laminated material at a region corresponding to the opening port, and a blank plate was prepared by subjecting the laminated material to ruling and punching with a punching die. The blank plate was subjected to end face processing, and a sleeve was formed by thermal adhesion of the body and was formed into a gable top-type paper container having an inner capacity of 500 mL with a molding and filling machine. The resulting paper container was filled with 500 mL of orange juice and sealed, while performing heat sterilization by hot filling at about 80? C., followed by storage at 25? C. for one month. The flavor and color tone of the orange juice after storage were verified. The flavor and the color tone were satisfactorily maintained.

Comparative Example 3-7

(132) A paper base laminated material and a paper container were produced as in Example 7 except that diester compound A and cobalt stearate were not used, and a storage test of orange juice was performed. The flavor and color tone of the orange juice after storage for one month slightly decreased.

(133) The paper container of Example 3-7 had satisfactory oxygen-absorbing performance, which demonstrated that the flavor and color tone of the contents were maintained even after storage.

Fourth Experiment

(134) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4 and diamide compound E having a tetralin ring produced in Synthesis Example 5 were used.

Example 4-1

(135) 95 parts by mass of a polyethylene terephthalate (product name: BK-2180, hereinafter referred to as PET, manufactured by Japan Unipet Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 260? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain oxygen-absorbing composition (1).

(136) Subsequently, under the following conditions, an injection molded article (parison) having a three-layer structure composed of layer B/oxygen-absorbing layer (layer A)/layer B was molded by injecting thermoplastic resin (b) constituting the layer B from an injection cylinder, then injecting a resin composition constituting the oxygen-absorbing layer (layer A) from another injection cylinder simultaneously with thermoplastic resin (b) constituting the layer B, and then injecting a necessary amount of thermoplastic resin (b) constituting the layer B to fill the cavity. The total mass of the parison was 28 g, and the mass of the layer A was 30% by mass based on the total mass of the parison. The resin composition constituting the oxygen-absorbing layer (layer A) was oxygen-absorbing composition (1), and the thermoplastic resin (b) was PET.

(137) (Shape of Parison)

(138) The parison had a total length of 95 mm, an outer diameter of 22 mm, and a thickness of 2.7 mm. The parison was produced with an injection molding machine (model: M200, providing four parisons, manufactured by Meiki Co., Ltd.).

(139) (Molding Conditions for Parison)

(140) Temperature of injection cylinder for layer A: 270? C.

(141) Temperature of injection cylinder for layer B: 270? C.

(142) Temperature of resin flow path in die: 270? C.

(143) Temperature of cooling water for die: 15? C.

(144) The resulting parison was cooled and was applied to secondary processing to produce a bottle by heating the parison and performing biaxial stretching blow molding.

(145) (Shape of Bottle Prepared by Secondary Processing)

(146) The bottle had a total length of 160 mm, an outer diameter of 60 mm, an internal volume of 350 mL, and a thickness of 0.40 mm. The stretching ratios were 1.9 times in the machine direction and 2.7 times in the transverse direction. The bottom shape was of a champagne type. The body had a dimple. The secondary processing was performed with a blow molding machine (model: EFB1000ET, manufactured by Frontier, Inc.).

(147) (Secondary Processing Conditions)

(148) Parison-heating temperature: 102? C.

(149) Pressure for stretching rod: 0.5 MPa

(150) Primary blow pressure: 0.7 MPa

(151) Secondary blow pressure: 2.5 MPa

(152) Primary blow delay time: 0.30 sec

(153) Primary blow time: 0.30 sec

(154) Secondary blow time: 2.0 sec

(155) Blow exhaust time: 0.6 sec

(156) Die temperature: 30? C.

(157) [Evaluation of Bottle Performance]

(158) The resulting bottle was evaluated through measurement of the oxygen transmission rate, verification of visibility of the contents, and an odor test in accordance with the following methods and criteria. (1) Measurement of Oxygen Transmission Rate of Bottle

(159) The oxygen transmission rate was measured on the 30th day from the start of the measurement in an atmosphere of a temperature of 23? C. and relative humidities of 50% (outside the bottle) and 100% (inside the bottle) with an oxygen transmission rate measurement apparatus (OX-TRAN 2-21 ML, manufactured by MOCON, Inc.). A lower measurement value indicates a higher oxygen barrier property. The detection lower limit is an oxygen transmission rate of 5?10.sup.?5 cc/(package-day-0.21 atm). The oxygen transmission rate was measured in accordance with ASTM D3985. (2) Visibility of Content in Bottle

(160) The visibility of the contents of the resulting bottle was visually observed. (3) Odor Test (Odor)

(161) The resulting bottle was filled with 350 mL of distilled water and was sealed with a polyethylene lid. The bottle was stored in an atmosphere of a temperature of 40? C. and a relative humidity of 90%, and the odor of the distilled water was then verified.

Example 4-2

(162) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that diester compound B was used instead of diester compound A. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Example 4-3

(163) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that diester compound C was used instead of diester compound A. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Example 4-4

(164) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that diester compound D was used instead of diester compound A. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Example 4-5

(165) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that diamide compound E was used instead of diester compound A. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Comparative Example 4-1

(166) A monolayer bottle having the same shape as that in Example 4-1 was produced using PET. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Comparative Example 4-2

(167) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that diester compound A was not used. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

Comparative Example 4-3

(168) An oxygen-absorbing multilayer bottle was produced as in Example 4-1 except that cobalt(II) stearate was not used. The oxygen transmission rate was measured, and the visibility and odor of the contents were verified.

(169) The following table shows the conditions and the evaluation results of the Examples and the Comparative Examples.

(170) TABLE-US-00008 TABLE 8 Inner and Oxygen-absorbing layer composition/parts by mass Oxygen transmission rate Visibility Layer outer layer Thermoplastic Compound having Transition (cc/package .Math. day .Math. of structure resin resin tetralin ring metal 0.21 atm) contents Odor Example 4-1 Three- PET PET Diester compound A Co 0.010 Good No layer (95) (5) (0.05) Example 4-2 Three- PET PET Diester compound B Co 0.015 Good No layer (95) (5) (0.05) Example 4-3 Three- PET PET Diester compound C Co 0.009 Good No layer (95) (5) (0.05) Example 4-4 Three- PET PET Diester compound D Co 0.008 Good No layer (95) (5) (0.05) Example 4-5 Three- PET PET Diamide compound E Co 0.018 Good No layer (95) (5) (0.05) Comparative Monolayer PET monolayer bottle 0.040 Good No Example 4-1 Comparative Three- PET PET Co 0.041 Good No Example 4-2 layer (100) (0.05) Comparative Three- PET PET Diester compound A 0.040 Good No Example 4-3 layer (95) (5)

Example 4-6

(171) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL L171B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition (2).

(172) Subsequently, under the following conditions, an injection molded cup having a three-layer structure composed of layer B/oxygen-absorbing layer (layer A)/layer B was molded by injecting thermoplastic resin (b) constituting the layer B from an injection cylinder, then injecting a resin composition constituting the oxygen-absorbing layer (layer A) from another injection cylinder simultaneously with injection of thermoplastic resin (b) constituting the layer B, and then injecting a necessary amount of thermoplastic resin (b) constituting the layer B to fill the cavity. The total mass of the injection cup was 31 g, and the mass of the layer A was 20% by mass based on the total mass of the injection cup. The resin composition constituting the oxygen-absorbing layer (layer A) was oxygen-absorbing composition (2), and the thermoplastic resin (b) was polypropylene (product name: NOVATEC PP MG03B, hereinafter also abbreviated to PP, manufactured by Japan Polypropylene Corporation).

(173) (Shape of Cup)

(174) The cup had a total length of 125 mm, a bottom diameter of 52 mm, a flange outside diameter of 70 mm, a flange inside diameter of 62 mm, a thickness of 1.1 mm, and an internal volume of 320 mL. The cup was produced with an injection molding machine (model: M200, providing four cups, manufactured by Meiki Co., Ltd.).

(175) (Molding Conditions for Cup)

(176) Temperature of injection cylinder for layer A: 220? C.

(177) Temperature of injection cylinder for layer B: 220? C.

(178) Temperature of resin flow path in die: 220? C.

(179) Temperature of cooling water for die: 15? C.

(180) [Evaluation of Cup Performance]

(181) The resulting cup was evaluated through measurement of the oxygen transmission rate, measurement of the oxygen concentration inside the sealed container after sealed storage, and an odor test in accordance with the following methods and criteria. (1) Oxygen Transmission Rate of Cup

(182) The oxygen transmission rate of the resulting cup was measured as in Example 4-1. (2) Measurement of Oxygen Concentration Inside Sealed Container

(183) The resulting cup was filled with 200 g of a humidity conditioning agent to adjust the relative humidity inside the container to 100% or 30%. An aluminum foil laminate film was used as a top film, and the initial oxygen concentration was adjusted to 2 vol % by nitrogen purge. The cup was sealed and was stored at 23? C. and a relative humidity of 50%. The oxygen concentration inside the container was measured after one month. (3) Odor Test

(184) The aluminum foil laminate film of the sealed container after measurement of the oxygen concentration inside the sealed container was opened, and the odor inside the container was verified. The odor was evaluated for whether or not the container itself had an odor and for whether or not the odor changed after oxygen absorption. When the container itself had no odor and when the odor did not change after oxygen absorption, the container was considered no odor inside container.

Example 4-7

(185) An oxygen-absorbing multilayer cup was produced as in Example 4-6 except that diester compound B was used instead of diester compound A. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Example 4-8

(186) An oxygen-absorbing multilayer cup was produced as in Example 4-6 except that diester compound C was used instead of diester compound A. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Example 4-9

(187) An oxygen-absorbing multilayer cup was produced as in Example 4-6 except that diester compound D was used instead of diester compound A. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Example 4-10

(188) An oxygen-absorbing multilayer cup was produced as in Example 4-6 except that diamide compound E was used instead of diester compound A. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Comparative Example 4-4

(189) A multilayer cup was produced as in Example 4-6 except that diester compound A and cobalt stearate were not used. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Comparative Example 4-5

(190) A multilayer cup was produced as in Example 4-6 except that cobalt stearate was not used. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Comparative Example 4-6

(191) A multilayer cup was produced as in Example 4-6 except that diester compound A was not used. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. No interlayer peeling of the cup was observed when the aluminum foil laminate film of the sealed container was opened.

Comparative Example 4-7

(192) An oxygen-absorbing multilayer cup was produced as in Example 4-6 except that nylon MXD6 (product name: MX nylon S6011, hereinafter also abbreviated to N-MXD6, manufactured by Mitsubishi Gas Chemical Company Inc.) was used instead of EVOH and that diester compound A was not used. The oxygen transmission rate and the oxygen concentration inside the sealed container were measured, and the odor was verified. The sealed container absorbed oxygen at a relative humidity of 100% of the inside of the container and thereby caused oxidative decomposition of the oxygen-absorbing layer (N-MXD6 layer), resulting in a reduction in strength and occurrence of interlayer peeling of the cup when the aluminum foil laminate film was opened.

(193) The following table shows the conditions and results of the Examples and the Comparative Examples.

(194) TABLE-US-00009 TABLE 9 Oxygen concentration Inner Oxygen inside container Odor inside and transmission (vol %) container outer Oxygen-absorbing layer composition/parts by mass rate.sup.1) Relative humidity Relative humidity Layer layer Thermoplastic Compound having Transition (cc/package .Math. day .Math. inside container inside container structure resin resin tetralin ring metal 0.21 atm) 30% 100% 30% 100% Example 4-6 Three- PP EVOH Diester compound A Co Undetectable ?0.1 ?0.1 No No layer (95) (5) (0.05) Example 4-7 Three- PP EVOH Diester compound B Co Undetectable 0.3 0.4 No No layer (95) (5) (0.05) Example 4-8 Three- PP EVOH Diester compound C Co Undetectable ?0.1 ?0.1 No No layer (95) (5) (0.05) Example 4-9 Three- PP EVOH Diester compound D Co Undetectable ?0.1 ?0.1 No No layer (95) (5) (0.05) Example 4-10 Three- PP EVOH Diamide compound E Co Undetectable 0.5 0.5 No No layer (95) (5) (0.05) Comparative Three- PP EVOH 0.0005 2.1 2.5 No No Example 4-4 layer (100) Comparative Three- PP PET Co 0.0005 2.2 2.4 No No Example 4-5 layer (100) (0.05) Comparative Three- PP PET Diester compound A 0.0005 2.1 2.5 No No Example 4-6 layer (95) (5) Comparative Three- PP N-MXD6 Co Undetectable 1.8 0.5 No No Example 4-7 layer (100) (0.05) .sup.1)Detection lower limit: 5 ? 10.sup.?5 cc/package-day .Math. 0.21 atm

(195) The containers of the Examples absorbed oxygen by the oxygen-absorbing layers and reduced the oxygen transmission rates, compared to those in the Comparative Examples. The strength was maintained even after oxygen absorption, and occurrence of odor was prevented.

Fifth Experiment

(196) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4, diamide compound E having a tetralin ring produced in Synthesis Example 5, and acid anhydride F having a tetralin ring produced in Synthesis Example 6 were used.

Example 5-1

(197) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL L171B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain oxygen-absorbing composition (1).

(198) An three-material five-layer oxygen-absorbing multilayer sheet was produced with a multilayer sheet molding apparatus composed of three extruders, a feed block, a T-die, a cooling roll, and a winding unit by extruding a cycloolefin copolymer (product name: TOPAS8007-F, hereinafter also abbreviated to COC, manufactured by TOPAS ADVANCED POLYMERS) as the material for the thermoplastic resin layer from the first extruder, maleic anhydride-modified polyolefin (product name: ADMER QF551, manufactured by Mitsui Chemicals Inc.) as the material for the adhesive layer from the second extruder, and oxygen-absorbing composition (1) as the material for the oxygen-absorbing layer from the third extruder and supplying the extrudates to the feed block. The resulting multilayer sheet had a layer structure of COC layer (100 ?m)/adhesive layer (10 ?m)/oxygen-absorbing layer (100 ?m)/adhesive layer (10 ?m)/COC layer (100 ?m). The numeric characters shown with a unit of ?m in the parentheses refer to the thickness.

(199) The resulting oxygen-absorbing sheet was produced into an oxygen-absorbing bottom member by plug assist pressure forming with a blister pack producing apparatus (trade name FBP-M2) manufactured by CKD Corporation. The number of shots in molding was fixed to 50 shots per minute. The oxygen-absorbing bottom member had dimensions of a bottom diameter of 10 mm, an upper (opening) diameter of 9 mm, and a depth of 4 mm.

(200) Separately, the following layers were laminated by extrusion lamination to produce a gas barrier lid member composed of aluminum foil (20 ?m)/urethane-based adhesive (product name: AD502/CAT10L, manufactured by Toyo-Morton, Ltd., 2 ?m)/CPP film (product name: Pylen Film-CT P1128, manufactured by Toyobo Co., Ltd., 25 ?m).

(201) Tablets each containing 20 mg of tocopherol acetate and having a diameter of 7 mm and a thickness of 3 mm were accommodated in the resulting oxygen-absorbing bottom member, and the COC layer of the oxygen-absorbing bottom member and the CPP film of the gas barrier lid member were then heat-sealed to prepare a sealed oxygen-absorbing PTP packaging body accommodating the tablet. The accommodated tablet was visible from the oxygen-absorbing bottom member side. The sealed PTP packaging body was stored in an environment of 40? C. and 60% RH, and the tocopherol acetate retention rate was measured after storage for six months in accordance with the quantitative measurement described in the Japanese Pharmacopoeia. The three-material five-layer oxygen-absorbing multilayer sheet was subjected to the following elution test.

(202) (Elution Test)

(203) The resulting oxygen-absorbing multilayer sheet was cut into a size of 1 cm?1 cm to prepare ten pieces of the oxygen-absorbing multilayer sheet. The ten pieces of the oxygen-absorbing multilayer sheet were stored in an environment of 40? C. and 90% RH for one month and were then immersed in 50 mL of pure water. The oxygen-absorbing multilayer sheet immersed in pure water was stored at 40? C. and 60% RH for four months, and the total amount of carbon (hereinafter also abbreviated to TOC) in the pure water was measured.

(204) (TOC Measurement)

(205) Apparatus: TOC-VCPH manufactured by Shimadzu Corporation

(206) Temperature of combustion furnace: 720? C.

(207) Gas/flow rate: high purity air, 150 mL/min at TOC meter portion

(208) Amount injected: 150 ?L

(209) Detection limit: 1 ?g/mL

Example 5-2

(210) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that diester compound B was used instead of diester compound A, and were evaluated as in Example 5-1.

Example 5-3

(211) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that diester compound C was used instead of diester compound A, and were evaluated as in Example 5-1.

Example 5-4

(212) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that diester compound D was used instead of diester compound A, and were evaluated as in Example 5-1.

Example 5-5

(213) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that diamide compound E was used instead of diester compound A, and were evaluated as in Example 5-1.

Example 5-6

(214) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that acid anhydride F was used instead of diester compound A, and were evaluated as in Example 5-1.

Comparative Example 5-1

(215) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that a COC monolayer sheet of 340 ?m was used instead of the multilayer sheet, and were evaluated as in Example 5-1.

Comparative Example 5-2

(216) An oxygen-absorbing multilayer sheet and an oxygen-absorbing PTP packaging body were produced as in Example 5-1 except that diester compound A and cobalt(II) stearate were not used, and were evaluated as in Example 5-1.

(217) The following table shows the conditions and results of the Examples and the Comparative Examples.

(218) TABLE-US-00010 TABLE 10 Tocopherol Amount of Inner and Thermoplastic Compound having acetate TOC in Layer outer layer resin tetralin ring retention elution test .sup.1) structure resin (parts by mass) rate (%) (?g/mL) Example 5-1 Five-layer COC EVOH Diester compound A 96 Undetectable 95 5 Example 5-2 Five-layer COC E VOH Diester compound B 93 Undetectable 95 5 Example 5-3 Five-layer COC EVOH Diester compound C 95 Undetectable 95 5 Example 5-4 Five-layer COC EVOH Diester compound D 97 Undetectable 95 5 Example 5-5 Five-layer COC E VOH Diamide compound E 87 Undetectable 95 5 Example 5-6 Five-layer COC EVOH Acid anhydride F 89 Undetectable 95 5 Comparative Monolayer COC COC 37 Undetectable Example 5-1 100 Comparative Five-layer COC EVOH 59 Undetectable Example 5-2 100 .sup.1) Detection lower limit: 0.1 ?g/mL

(219) As obvious from the table, the oxygen-absorbing PTP packaging body of each Example had a satisfactory oxygen barrier property and showed satisfactory storage performance for a medicinal tablet even after long-term storage. In addition, the TOC was undetectable in the elution test of the oxygen-absorbing multilayer sheet, which at least demonstrated a high safety of the oxygen-absorbing PTP packaging body.

Sixth Experiment

(220) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4 and diamide compound E having a tetralin ring produced in Synthesis Example 5 were used.

Example 6-1

(221) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL SP521B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(222) An oxygen-absorbing multilayer sheet was formed with a three-material five-layer multilayer sheet molding apparatus equipped with first to third extruders, a feed block, a T-die, a cooling roll, and a sheet take-up unit by extruding polypropylene (product name: NOVATEC PP FY6C, hereinafter also abbreviated to PP1, manufactured by Japan Polypropylene Corporation) from the first extruder, the oxygen-absorbing composition from the second extruder, and adhesive polypropylene (product name: MODIC P604V, hereinafter also abbreviated to adhesive PP, manufactured by Mitsubishi Chemical Corporation) from the third extruder and supplying the extrudates to the feed block. The multilayer sheet had a layer structure composed of PP1 (400 ?m)/adhesive PP (15 ?m)/oxygen-absorbing layer (100 ?m)/adhesive PP (15 ?m)/PP1 (400 ?m) in this order from the inner layer. The numeric characters shown with a unit of ?m in the parentheses refer to the thickness. The same applies to the following Examples unless specifically indicated otherwise.

(223) Subsequently, the resulting oxygen-absorbing multilayer sheet was thermoformed into a tray-shaped oxygen-absorbing multilayer container having an internal volume of 400 cc and a surface area of 200 cm.sup.2 with a vacuum molding apparatus equipped with a plug assist.

(224) In the resulting oxygen-absorbing multilayer container, 110 g of washed rice and 90 g of sterilized water were placed. The oxygen inside the container was purged with a nitrogen gas to reduce the oxygen concentration to 0.2 vol %. Subsequently, the container was sealed by heat sealing using a gas barrier film (product name: EVAL EFCR-15, manufactured by Kuraray Co., Ltd.) as the lid member. This container was placed in an autoclave pot and was subjected to heating rice cooking at 105? C. for 40 min. After cooling, the oxygen concentration inside the container was measured, and the container was stored under conditions of 23? C. and 50% RH. The oxygen concentration inside the container was measured again three months after the start of storage, and the container was opened to verify the flavor of the cooked rice.

Example 6-2

(225) An oxygen-absorbing multilayer container was produced as in Example 6-1 except that diester compound B was used instead of diester compound A and was subjected to a storage test as in Example 6-1.

Example 6-3

(226) An oxygen-absorbing multilayer container was produced as in Example 6-1 except that diester compound C was used instead of diester compound A and was subjected to a storage test as in Example 6-1.

Example 6-4

(227) An oxygen-absorbing multilayer container was produced as in Example 6-1 except that diester compound D was used instead of diester compound A and was subjected to a storage test as in Example 6-1.

Example 6-5

(228) An oxygen-absorbing multilayer container was produced as in Example 6-1 except that diamide compound E was used instead of diester compound A and was subjected to a storage test as in Example 6-1.

Comparative Example 6-1

(229) A multilayer sheet and a multilayer container were produced as in Example 6-1 except that diester compound A was not used and were subjected to a storage test as in Example 6-1.

(230) The following table shows the conditions and results of the Examples and the Comparative Examples.

(231) TABLE-US-00011 TABLE 11 After heating and cooking rice and Oxygen-absorbing layer composition (parts by mass) cooling rice After storage for 3 months .sup.1) Thermoplastic Compound having Transition Oxygen concentration Oxygen concentration Flavor of resin tetralin ring metal inside container (%) inside container (%) cooked rice .sup.2) Example 6-1 95 5 0.05 3.5 0.2 ? (EVOH) (Diester compound A) (Co) Example 6-2 95 5 0.05 3.6 0.4 ? (EVOH) (Diester compound B) (Co) Example 6-3 95 5 0.05 3.8 0.5 ? (EVOH) (Diester compound C) (Co) Example 6-4 95 5 0.05 3.5 0.2 ? (EVOH) (Diester compound D) (Co) Example 6-5 95 5 0.05 3.8 1.2 ? (EVOH) (Diamide compound E) (Co) Comparative 100 4.2 6.0 X Example 6-1 (EVOH) .sup.1) Stored at a temperature of 23? C. and a relative humidity of 50% .sup.2) ?: good, ?: almost good, X: deteriorated

(232) As obvious from the table, it was at least observed that the oxygen-absorbing multilayer containers of the Examples had excellent oxygen-absorbing performance and satisfactorily maintained the flavor of cooked rice and were suitable for storage of cooked rice.

Seventh Experiment

(233) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4 and diamide compound E having a tetralin ring produced in Synthesis Example 5 were used.

Example 7-1

(234) 95 parts by mass of a polyethylene terephthalate (product name: BK-2180, hereinafter referred to as PET, manufactured by Japan Unipet Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 270? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(235) Subsequently, under the following conditions, an injection molded article (parison) having a three-layer structure composed of layer B/oxygen-absorbing layer (layer A)/layer B was molded by injecting thermoplastic resin (b) constituting the layer B from an injection cylinder, then injecting a resin composition constituting the oxygen-absorbing layer (layer A) from another injection cylinder simultaneously with thermoplastic resin (b) constituting the layer B, and then injecting a necessary amount of thermoplastic resin (b) constituting the layer B to fill the cavity. The total mass of the parison was 28 g, and the mass of the layer A was 30% by mass based on the total mass of the parison. The resin composition constituting the oxygen-absorbing layer (layer A) was oxygen-absorbing composition, and the thermoplastic resin (b) was PET.

(236) (Shape of Parison)

(237) The parison had a total length of 95 mm, an outer diameter of 22 mm, and a thickness of 2.7 mm. The parison was produced with an injection molding machine (model: M200, providing four parisons, manufactured by Meiki Co., Ltd.).

(238) (Molding Conditions for Parison)

(239) Temperature of injection cylinder for layer A: 270? C.

(240) Temperature of injection cylinder for layer B: 270? C.

(241) Temperature of resin flow path in die: 270? C.

(242) Temperature of cooling water for die: 15? C.

(243) The resulting parison was cooled and was applied to secondary processing to produce a bottle by heating the parison and performing biaxially stretching blow molding.

(244) (Shape of Bottle Prepared by Secondary Processing)

(245) The bottle had a total length of 160 mm, an outer diameter of 60 mm, an internal volume of 350 mL, and a thickness of 0.40 mm. The stretching ratios were 1.9 times in the machine direction and 2.7 times in the transverse direction. The bottom shape was of a champagne type. The body had a dimple. The secondary processing was performed with a blow molding machine (model: EFB1000ET, manufactured by Frontier, Inc.).

(246) (Secondary Processing Conditions)

(247) Parison-heating temperature: 102? C.

(248) Pressure for stretching rod: 0.5 MPa

(249) Primary blow pressure: 0.7 MPa

(250) Secondary blow pressure: 2.5 MPa

(251) Primary blow delay time: 0.30 sec

(252) Primary blow time: 0.30 sec

(253) Secondary blow time: 2.0 sec

(254) Blow exhaust time: 0.6 sec

(255) Die temperature: 30? C.

(256) The resulting oxygen-absorbing multilayer bottle was filled with 350 mL of Awamori, an alcoholic beverage, and was sealed, followed by storage at 35? C. The flavor of the Awamori was verified 30 days, 45 days, and 60 days after the start of the storage.

Example 7-2

(257) An oxygen-absorbing multilayer bottle was produced as in Example 7-1 except that diester compound B was used instead of diester compound A and was subjected to a storage test as in Example 7-1.

Example 7-3

(258) An oxygen-absorbing multilayer bottle was produced as in Example 7-1 except that diester compound C was used instead of diester compound A and was subjected to a storage test as in Example 7-1.

Example 7-4

(259) An oxygen-absorbing multilayer bottle was produced as in Example 7-1 except that diester compound D was used instead of diester compound A and was subjected to a storage test as in Example 7-1.

Example 7-5

(260) An oxygen-absorbing multilayer bottle was produced as in Example 7-1 except that diamide compound E was used instead of diester compound A and was subjected to a storage test as in Example 7-1.

Comparative Example 7-1

(261) A monolayer bottle having the same shape as that in Example 7-1 was produced using PET and was subjected to a storage test as in Example 7-1.

(262) The following table shows the conditions and results of the Examples and the Comparative Examples.

(263) TABLE-US-00012 TABLE 12 Oxygen-absorbing layer composition/parts by mass Flavor.sup.1) Layer Inner and outer Thermoplastic Compound having Transition After 30 After 45 After 60 structure layer resin resin tetralin ring metal days days days Example 7-1 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound A) (Co) Example 7-2 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound B) (Co) Example 7-3 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound C) (Co) Example 7-4 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound D) (Co) Example 7-5 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diamide compound E) (Co) Comparative Monolayer PET monolayer bottle ? ? X Example 7-1 .sup.1)?: good, ?: almost good, X: deteriorated

(264) As obvious from the table, it was at least observed that the oxygen-absorbing multilayer containers of the Examples had excellent oxygen-absorbing performance, satisfactorily maintained the flavor of Awamori, and were suitable for storage of Awamori.

(265) In contrast, the PET monolayer bottle evaluated in Comparative Example 7-1 did not show an oxygen-absorbing function to significantly reduce the flavor of Awamori.

Eighth Experiment

(266) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4 and diamide compound E having a tetralin ring produced in Synthesis Example 5 were used.

Example 8-1

(267) 95 parts by mass of a polyethylene terephthalate (product name: BK-2180, hereinafter referred to as PET, manufactured by Japan Unipet Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 270? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain an oxygen-absorbing composition.

(268) Subsequently, under the following conditions, an injection molded article (parison) having a three-layer structure composed of layer B/oxygen-absorbing layer (layer A)/layer B was molded by injecting thermoplastic resin (b) constituting the layer B from an injection cylinder, then injecting a resin composition constituting the oxygen-absorbing layer (layer A) from another injection cylinder simultaneously with thermoplastic resin (b) constituting the layer B, and then injecting a necessary amount of thermoplastic resin (b) constituting the layer B to fill the cavity. The total mass of the parison was 28 g, and the mass of the layer A was 30% by mass based on the total mass of the parison. The resin composition constituting the oxygen-absorbing layer (layer A) was oxygen-absorbing composition, and the thermoplastic resin (b) was PET.

(269) (Shape of Parison)

(270) The parison had a total length of 95 mm, an outer diameter of 22 mm, and a thickness of 2.7 mm. The parison was produced with an injection molding machine (model: M200, providing four parisons, manufactured by Meiki Co., Ltd.).

(271) (Molding Conditions for Parison)

(272) Temperature of injection cylinder for layer A: 270? C.

(273) Temperature of injection cylinder for layer B: 270? C.

(274) Temperature of resin flow path in die: 270? C.

(275) Temperature of cooling water for die: 15? C.

(276) The resulting parison was cooled and was applied to secondary processing to produce a bottle by heating the parison and performing biaxially stretching blow molding.

(277) (Shape of Bottle Prepared by Secondary Processing)

(278) The bottle had a total length of 160 mm, an outer diameter of 60 mm, an internal volume of 350 mL, and a thickness of 0.40 mm. The stretching ratios were 1.9 times in the machine direction and 2.7 times in the transverse direction. The bottom shape was of a champagne type. The body had a dimple. The secondary processing was performed with a blow molding machine (model: EFB1000ET, manufactured by Frontier, Inc.).

(279) (Secondary Processing Conditions)

(280) Parison-heating temperature: 102? C.

(281) Pressure for stretching rod: 0.5 MPa

(282) Primary blow pressure: 0.7 MPa

(283) Secondary blow pressure: 2.5 MPa

(284) Primary blow delay time: 0.30 sec

(285) Primary blow time: 0.30 sec

(286) Secondary blow time: 2.0 sec

(287) Blow exhaust time: 0.6 sec

(288) Die temperature: 30? C.

(289) The resulting oxygen-absorbing multilayer bottle was filled with 350 mL of orange juice and was sealed, followed by storage at 35? C. The flavor of the orange juice was then verified 30 days, 45 days, and 60 days after the start of the storage.

Example 8-2

(290) An oxygen-absorbing multilayer bottle was produced as in Example 8-1 except that diester compound B was used instead of diester compound A and was subjected to a storage test as in Example 8-1.

Example 8-3

(291) An oxygen-absorbing multilayer bottle was produced as in Example 8-1 except that diester compound C was used instead of diester compound A and was subjected to a storage test as in Example 8-1.

Example 8-4

(292) An oxygen-absorbing multilayer bottle was produced as in Example 8-1 except that diester compound D was used instead of diester compound A and was subjected to a storage test as in Example 8-1.

Example 8-5

(293) An oxygen-absorbing multilayer bottle was produced as in Example 8-1 except that diamide compound E was used instead of diester compound A and was subjected to a storage test as in Example 8-1.

Comparative Example 8-1

(294) A monolayer bottle having the same shape as that in Example 8-1 was produced using PET and was subjected to a storage test as in Example 8-1.

(295) The following table shows the conditions and results of the Examples and the Comparative Examples.

(296) TABLE-US-00013 TABLE 13 Oxygen-absorbing layer composition/parts by mass Flavor.sup.1) Layer Inner and outer Thermoplastic Compound having Transition After 30 After 45 After 60 structure layer resin resin tetralin ring metal days days days Example 8-1 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound A) (Co) Example 8-2 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound B) (Co) Example 8-3 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound C) (Co) Example 8-4 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diester compound D) (Co) Example 8-5 Three-layer PET 95 5 0.05 ? ? ? (PET) (Diamide compound E) (Co) Comparative Monolayer PET monolayer bottle ? ? X Example 8-1 .sup.1)?: good, ?: almost good, X: deteriorated

(297) As obvious from the table, it was at least observed that the oxygen-absorbing multilayer containers of the Examples had excellent oxygen-absorbing performance, satisfactorily maintained the flavor of orange juice, and were suitable for storage of fruit juice and/or vegetable juice.

Ninth Experiment

(298) Diester compounds A to D having tetralin rings produced in Synthesis Examples 1 to 4, diamide compound E having a tetralin ring produced in Synthesis Example 5, and acid anhydride F having a tetralin ring produced in Synthesis Example 6 were used.

Example 9-1

(299) 95 parts by mass of an ethylene-vinyl alcohol copolymer (product name: EVAL L171B, hereinafter also abbreviated to EVOH, manufactured by Kuraray Co., Ltd.), 5 parts by mass of diester compound A, and cobalt(II) stearate giving 0.05 parts by mass of cobalt were melt-kneaded with a twin-screw extruder having two 37-mm diameter screws at 220? C., extruded into a strand from the extruder head, cooled, and then pelletized to obtain oxygen-absorbing composition (1).

(300) Subsequently, an oxygen-absorbing multilayer film composed of PP layer (60 ?m)/adhesive layer (5 ?m)/oxygen-absorbing resin layer (30 ?m)/adhesive layer (5 ?m)/PP layer (60 ?m) was produced by an inflation process using a three-material five-layer film molding apparatus assembled from two extruders of 50 mm in diameter and an extruder of 40 mm in diameter by coextruding polypropylene (product name: NOVATEC PP, FG3DC, hereinafter also abbreviated to PP, manufactured by Japan Polypropylene Corporation) from the first extruder of 50 mm in diameter, oxygen-absorbing composition (1) from the second extruder of 50 mm in diameter, and maleic anhydride-modified polyolefin (product name: ADMER QF551, manufactured by Mitsui Chemicals Inc.) as the material for the adhesive layer from the extruder of 40 mm in diameter. The numeric characters shown with a unit of ?m in the parentheses refer to the thickness.

(301) The resulting oxygen-absorbing multilayer film was produced into a three-side sealed bag of 220 mm?300 mm. The three-side sealed bag was filled with 1000 cc of a 50% glucose solution and was then sealed. The thus-prepared sealed bag was treated with heat at 121? C. for 20 min and was then stored in an environment of 40? C. and 60% RH for one month. The glucose retention rate after the storage was measured in accordance with the quantitative measurement described in the Japanese Pharmacopoeia. The oxygen-absorbing multilayer film was subjected to the following elution test.

(302) (Elution Test)

(303) The resulting oxygen-absorbing multilayer sheet was cut into a size of 1 cm?1 cm to prepare ten pieces of the oxygen-absorbing multilayer sheet. The ten pieces of the oxygen-absorbing multilayer sheet were stored in an environment of 40? C. and 90% RH for one month and were then immersed in 50 mL of pure water. The oxygen-absorbing multilayer sheet immersed in pure water was stored at 40? C. and 60% RH for four months, and the total amount of carbon (hereinafter also abbreviated to TOC) in the pure water was measured.

(304) (TOC Measurement)

(305) Apparatus: TOC-VCPH manufactured by Shimadzu Corporation

(306) Temperature of combustion furnace: 720? C.

(307) Gas/flow rate: high purity air, 150 mL/min at TOC meter portion

(308) Amount injected: 150 ?L

(309) Detection limit: 1 ?g/mL

Example 9-2

(310) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that diester compound B was used instead of diester compound A and were evaluated as in Example 9-1.

Example 9-3

(311) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that diester compound C was used instead of diester compound A and were evaluated as in Example 9-1.

Example 9-4

(312) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that diester compound D was used instead of diester compound A and were evaluated as in Example 9-1.

Example 9-5

(313) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that diamide compound E was used instead of diester compound A and were evaluated as in Example 9-1.

Example 9-6

(314) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that acid anhydride F was used instead of diester compound A and were evaluated as in Example 9-1.

Comparative Example 9-1

(315) A sealed bag was produced as in Example 9-1 except that a PP monolayer film (thickness: 160 ?m) was used instead of the multilayer film and was evaluated as in Example 9-1.

Comparative Example 9-2

(316) An oxygen-absorbing multilayer film and a sealed bag were produced as in Example 9-1 except that diester compound A was not used and were evaluated as in 9-1.

(317) The following table shows the conditions and results of the Examples and the Comparative Examples.

(318) TABLE-US-00014 TABLE 14 Oxygen-absorbing layer composition (parts by mass) Glucose Amount of TOC Layer Inner and outer Thermoplastic Compound having Transition retention in elution test .sup.1) structure layer resin resin tetralin ring metal rate (%) (?g/mL) Example 9-1 Five-layer PP EVOH Diester compound A 0.05 91% Undetectable 95 5 (Co) Example 9-2 Five-layer PP EVOH Diester compound B 0.05 88% Undetectable 95 5 (Co) Example 9-3 Five-layer PP EVOH Diester compound C 0.05 90% Undetectable 95 5 (Co) Example 9-4 Five-layer PP EVOH Diester compound D 0.05 93% Undetectable 95 5 (Co) Example 9-5 Five-layer PP EVOH Diamide compound E 0.05 84% Undetectable 95 5 (Co) Example 9-6 Five-layer PP EVOH Acid anhydride F 0.05 86% Undetectable 95 5 (Co) Comparative Monolayer PP PP 27% Undetectable Example 9-1 100 Comparative Five-layer PP EVOH 49% Undetectable Example 9-2 100 .sup.1) Detection lower limit: 0.1 (?g/mL)

(319) As obvious from the table, the drug solutions stored by the storage methods of the Examples were prevented from degradation in the drug ingredients even after long-term storage. In addition, the amount of elution from the oxygen-absorbing multilayer film into the contents was small, which at least demonstrated that the method could satisfactorily store, for example, a drug solution.

INDUSTRIAL APPLICABILITY

(320) The oxygen-absorbing multilayer body, oxygen-absorbing paper container, oxygen-absorbing container, oxygen-absorbing sealed container, and oxygen-absorbing PTP packaging body of the present invention have excellent oxygen-absorbing performance and therefore can be widely and effectively used in a general technical field requiring oxygen absorption. In addition, these products and storage methods using them can absorb oxygen regardless of the presence or absence of moisture in the article to be stored and can further prevent an increase in odor strength after oxygen absorption and therefore can be effectively used in, in particular, for example, foods, cooked foods, beverages, medicinal products, and health foods. Moreover, the oxygen-absorbing multilayer body and other products of the present invention are not responsive to a metal detector and therefore can be widely and effectively used in packaging materials, containers, etc. that are required to be inspected with a metal detector for metals, metal pieces, etc. from the outside.

(321) The present application is based on the following Japanese Patent Applications, the contents of which are incorporated herein by reference:

(322) Japanese Patent Application (Patent Application No. 2013-044752) filed with the Japan Patent Office on Mar. 6, 2013;

(323) Japanese Patent Application (Patent Application No. 2013-044233) filed with the Japan Patent Office on Mar. 6, 2013;

(324) Japanese Patent Application (Patent Application No. 2013-044753) filed with the Japan Patent Office on Mar. 6, 2013;

(325) Japanese Patent Application (Patent Application No. 2013-044422) filed with the Japan Patent Office on Mar. 6, 2013;

(326) Japanese Patent Application (Patent Application No. 2013-044423) filed with the Japan Patent Office on Mar. 6, 2013;

(327) Japanese Patent Application (Patent Application No. 2013-044424) filed with the Japan Patent Office on Mar. 6, 2013;

(328) Japanese Patent Application (Patent Application No. 2013-044234) filed with the Japan Patent Office on Mar. 6, 2013;

(329) Japanese Patent Application (Patent Application No. 2013-044425) filed with the Japan Patent Office on Mar. 6, 2013; and

(330) Japanese Patent Application (Patent Application No. 2013-044235) filed with the Japan Patent Office on Mar. 6, 2013.