POLYESTER-BASED RESIN COMPOSITION

Abstract

The polyester-based resin composition according to the invention is a polyester resin composition, containing: at least a polyester resin (A); and a surfactant (B), in which the polyester resin (A) is a copolymer of a compound having a polyalkylene glycol with from 3 to 50 repeating units as a structure as a constituent component, the surfactant (B) is a nonionic surfactant having a structure of a polyalkylene glycol, and the contact angle of water is 30 or less.

Claims

1. A polyester-based resin composition, comprising: a polyester resin (A); and a surfactant (B), wherein the polyester resin (A) is a copolymer of a compound having a polyalkylene glycol with from 3 to 50 repeating units as a structure as a constituent component, the surfactant (B) is a nonionic surfactant having a structure of a polyalkylene glycol, and the contact angle of water is 30 or less.

2. The polyester-based resin composition according to claim 1, wherein the polyalkylene glycol in the compound having a polyalkylene glycol with from 3 to 50 repeating units as a structure that is a constituent component of the polyester resin (A) has a structure represented by the following Formula (1) or (2).
HO-((CH.sub.2).sub.aO).sub.b-H (1)
HO-(CH.sub.2CH((CH.sub.2).sub.cCH.sub.3)O).sub.d-H (2) (where a: from 2 to 4, c: from 0 to 1, b and d: from 3 to 50)

3. The polyester-based resin composition according to claim 1, wherein the content of the polyalkylene glycol derived from the compound having a polyalkylene glycol with from 3 to 50 repeating units as a structure which is a constituent component of the polyester resin (A) is from 0.1 to 35% by weight.

4. The polyester-based resin composition according to claim 1, wherein the number average molecular weight of the polyester resin (A) is from 5,000 to 35,000.

5. The polyester-based resin composition according to claim 1, wherein the surfactant (B) has a structure represented by the following Formula (3) or (4).
RO-((CH.sub.2).sub.eO).sub.f-H (3)
RO-(CH.sub.2CH((CH.sub.2).sub.gCH.sub.3)O).sub.h-H (4) (where R represents any one of an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, a cyclic ether group and an aryl group, e: from 2 to 4, g: from 0 to 1, f and h: 2 or more)

6. The polyester-based resin composition according to claim 1, wherein the content of the surfactant (B) is from 0.1 to 20% by weight.

7. An adhesive composition obtained by dissolving the polyester-based resin composition according to claim 1 in an organic solvent.

Description

EXAMPLES

[0061] The invention will be specifically described based on Examples and Comparative Examples, but the invention is not limited thereto.

1. Evaluation Method

1-1. Contact Angle

[0062] The contact angle of water was measured at 25 C. by the sessile drop method prescribed in JIS R 3257 (established in 1999). A contact angle measurement apparatus used is a CA-X type contact angle meter manufactured by Kyowa Interface Science Co., Ltd.

1-2. Number Average Molecular Weight

[0063] Apparatus: HLC-8220GPC (manufactured by TOSOH CORPORATION) [0064] Column: TSKgel GMHXL2 (manufactured by TOSOH CORPORATION) [0065] Column temperature: 40 C. [0066] Eluent: tetrahydrofuran 1.00 mL/min. [0067] Detector: RI (differential refractometer) [0068] The molecular weight measured by GPC was converted based on the molecular weight of polystyrene.

1-3. Monomer Composition of Polyester Resin

[0069] .sup.1H-NMR was measured using an NMR measuring apparatus, and the resin composition was determined from the peak intensity of each copolymerization component. As a measurement solvent, deuterated chloroform was used.

1-4. Melting Point, Glass Transition Point

[0070] The measurement was carried out with a differential scanning calorimeter (DSC). The programming rate was 10 C./min.

1-5. Stability Test of Adhesive Composition

[0071] 70 g of an adhesive composition was placed in a 100 mL glass bottle, and the bottle was sealed tightly. After standing at 5 C. for 7 days, visual evaluation was performed according to the following criteria.

[0072] A: The composition remained liquid. B: The composition solidified in an agar state and returned to a liquid state at 25 C. C: The composition solidified in an agar state and did not return to a liquid state at 25 C.

1-6. Peel Strength

(1) Preparation of Test Pieces

[0073] An aluminum foil (100 mm200 mm) having a thickness of 40 m was coated with an adhesive composition with a bar coater, and then, dried at 100 C. for 3 minutes to remove an organic solvent contained in the adhesive composition to form an adhesive layer having a thickness of 30 m. Subsequently, a PET film having a thickness of 100 m was laminated on the surface of the adhesive layer, and the film was pressure bonded from the surface of the aluminum foil using a thermal gradient tester to obtain a test piece. The bonding conditions at this time were a temperature of 100 C., a pressure of 0.3 MPa, and a pressing time of 2 seconds.

(2) Measurement of T Peel Strength

[0074] The test piece was cut into a width of 10 mm, and the T peel strength (N/10 mm) between an aluminum foil and PET was measured. The measurement conditions are a temperature of 25 C. and a pulling rate of 100 mm/min.

[0075] 2. Raw Materials

[0076] (1) Surfactant

(S-1): Polyoxyethylene lauryl ether (EMULGEN 103 manufactured by Kao Corporation), HLB 8.1)
(S-2): Polyoxyethylene sorbitan monolaurate (RHEODOL TW-L106 manufactured by Kao Corporation, HLB 13.3
(S-3): Coconut amine acetate (ACETAMIN 24 manufactured by Kao Corporation)
(S-4): Sodium dodecylbenzenesulfonate (NEOPEREX G-65 manufactured by Kao Corporation)

(Synthesis of Polyester Resin)

Synthesis Example 1

[0077] As shown in Table 1, 159 parts by weight of terephthalic acid, 52.9 parts by weight of isophthalic acid, 65.9 parts by weight of sebacic acid, 91.1 parts by weight of ethylene glycol, 92.5 parts by weight of 1,6-hexanediol, 39.1 parts by weight of PEG 200, and 0.3 parts by weight of tetrabutyl titanate as a polymerization catalyst were charged into a reactor, and the interior of the system was replaced with nitrogen. Thereafter, while stirring these raw materials at 300 rpm, the reactor was heated at 230 C. and the mixture was melted. After the temperature in the reactor reached 230 C., an esterification reaction was allowed to proceed for 3 hours. After 3 hours, the temperature in the system was brought to 240 C., and the pressure in the system was reduced. After the inside of the system reached a high vacuum (pressure: from 0.1 to 10.sup.5 Pa), a polymerization reaction was further performed for 5 hours to obtain a polyester resin (P-1). The polyester resin (P-1) had a number average molecular weight of 19,000, a melting point of 68 C., and a glass transition point of 3 C. The results are shown in Table 2. The content of polyalkylene glycol was determined by NMR measurement of the obtained polyester resin.

TABLE-US-00001 TABLE 1 Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Example Example Example Example Example Example Example Example Example Example Raw material name 1 2 3 4 5 6 7 8 9 10 Charged EG 91.1 94.0 93.6 87.3 84.3 81.5 86.9 86.4 85.8 94.1 com- HG 92.5 119 115 59.1 32.1 6.9 105 107 107 119 position PEG200 39.1 0.3 6.7 87.6 127 163 (weight) PEG1000 43.5 PEG2000 43.3 PEG3000 46.1 TPA 159 164 163 152 147 142 151 150 149 164 IPA 52.9 54.6 54.3 50.7 48.9 47.3 50.4 50.1 49.8 54.6 SEA 65.9 68.1 67.7 63.2 61.1 59.0 62.9 62.6 62.1 68.1 Tetrabutyl titanate 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3

TABLE-US-00002 TABLE 2 Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Synthesis Example Example Example Example Example Example Example Example Example Example 1 2 3 4 5 6 7 8 9 10 Resin name P-1 P-2 P-3 P-4 P-5 P-6 P-7 P-8 P-9 P-10 Compoisition EG 20 20 20 20 20 20 20 20 20 20 (mol %) HG 24 30 29 16 9 2 29 29 30 30 PEG200 6.0 0.05 1.0 14 21 28 PEG1000 1.4 PEG2000 0.7 PEG3000 0.5 TPA 30 30 30 30 30 30 30 30 30 30 IPA 10 10 10 10 10 10 10 10 10 10 SEA 10 10 10 10 10 10 10 10 10 10 Polyalkylene glycol 9.8 0.1 1.7 21 31 39 11 11 11 content (% by weight) Number average 19,000 20,000 19,500 19,000 20,100 21,000 20,000 19,000 19,000 20,000 molecular weight Melting point ( C.) 68.0 70.0 68.0 72 60 58 68 68 68 70.0 Glass transition point ( C.) 3.0 1.0 2.0 20 22 25 8 8 8 1.0

Synthesis Examples 2 to 10

[0078] Polycondensation of a polyester resin was carried out in the same manner as in Synthesis Example 1 except that the type of monomer used and the charge composition thereof were changed as shown in Table 1. The physical properties of the obtained polyester resin are shown in Table 2.

[0079] Abbreviations in Table 1 and Table 2 described below are as follows. [0080] TPA: Terephthalic acid [0081] IPA: Isophthalic acid [0082] SEA: Sebacic acid [0083] EG: Ethylene glycol [0084] HG: 1,6-hexane diol [0085] PEG200: Polyethylene glycol (molecular weight: 200, repeating units: about 4.6) [0086] PEG1000: Polyethylene glycol (molecular weight: 1,000, repeating units: about 23) [0087] PEG2000: Polyethylene glycol (molecular weight: 2,000, repeating units: about 45) [0088] PEG3000: Polyethylene glycol (molecular weight: 3,000, repeating units: about 68)

[0089] The final resin compositions and characteristic values of the obtained polyester resins (P-1) to (P-10) are shown in Table 2.

Example 1

[0090] 100 parts by weight of the polyester resin (P-1) synthesized in Synthesis Example 1 and 0.1 parts by weight of the surfactant (S-1) were dissolved in 125 parts by weight of toluene and 125 parts by weight of methyl ethyl ketone to obtain an adhesive having a solid content concentration of 29% by weight. Various evaluations were performed using the obtained adhesive. The results are shown in Table 3.

Examples 2 TO 12, and Comparative Examples 1 TO 5

[0091] An adhesive was obtained in the same manner as in Example 1 except that the types and amounts of the polyester resin and surfactant were changed as shown in Table 3 and Table 4 and various evaluations were performed. The results are shown in Tables 3 and 4.

TABLE-US-00003 TABLE 3 Example Example Example Example Example Example Example Example Example Example Example Example 1 2 3 4 5 6 7 8 9 10 11 12 Polyester Synthesis 100 100 100 100 100 resin Example 1 (P-1) Synthesis 100 Example 2 (P-2) Synthesis 100 Example 3 (P-3) Synthesis 100 Example 4 (P-4) Synthesis 100 Example 5 (P-5) Synthesis 100 Example 6 (P-6) Synthesis 100 Example 7 (P-7) Synthesis 100 Example 8 (P-8) Surfactant (S-1) 0.1 5.0 10.0 15.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 (S-2) 5.0 Organic toluene 125 125 125 125 125 125 125 125 125 125 125 125 solvent methyl ethyl 125 125 125 125 125 125 125 125 125 125 125 125 keetone Solution appearance A A A A A A A A A A A A Contact angle (water, 20 10 5 5 10 10 10 10 10 5 10 10 25 C.) Peel strength (N/10 mm) 24 22 20 10 22 20 20 22 20 10 22 22

TABLE-US-00004 TABLE 4 Comparative Comparative Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Polyester Synthesis 100 100 100 resin Example 1 (P-1) Synthesis 100 Example 9 (P-9) Synthesis 100 Example 10 (P-10) Surfactant (S-1) 5.0 5.0 (S-3) 5.0 (S-4) 5.0 Organic Toluene 125 125 125 125 125 solvent Methyl 125 125 125 125 125 ethyl ketone Solution appearance A A A A A Contact angle 65 70 5 5 5 (water, 25 C.) Peel strength 24 24 8 7 5 (N/10 mm)

[0092] According to the results of Table 3, the adhesive compositions of Examples 1 to 12 had a contact angle of water of 30 or less, a peel strength as high as 10 N/10 mm or higher, and it was possible to obtain a polyester resin-based adhesive composition having both wettability against water and peel strength and the stability of an adhesive solution was also favorable.

[0093] In Comparative Example 1, the peel strength was 24 N/10 mm, which was favorable, but since the surfactant described in claim 1 was not contained, the contact angle of water was 65.

[0094] In Comparative Example 2, the peel strength was 24 N/10 mm, which was favorable, but since the surfactant contained was not a nonionic surfactant having a polyalkylene glycol structure, the contact angle of water was 70.

[0095] In Comparative Example 3, the contact angle of water was 5, but since the surfactant contained was not a nonionic surfactant having a polyalkylene glycol structure, the peel strength was 8 N/10 mm.

[0096] In Comparative Example 4, the contact angle of water was 5, but since the number of repeating units of a polyalkylene glycol copolymerized in the polyester resin exceeded the range shown in claim 1, the peel strength was 7 N/10 mm.

[0097] In Comparative Example 5, the contact angle of water was 5, but since a polyalkylene glycol was not copolymerized in the polyester resin, the peel strength was 5 N/10 mm.

INDUSTRIAL APPLICABILITY

[0098] The adhesive composition of the invention has properties of a polyester resin-based adhesive, is excellent in adhesion to a metal or resin material and mechanical properties, and the contact angle of water on the resin surface is 30 or less, and the resin surface exposed without being adhered maintains a state of favorable wettability to water. Such properties are suitably used as a hot melt adhesive having favorable ink transferability, such as when printing on a portion of an adhesive layer.