Synthetic resin laminate

Abstract

A synthetic resin laminate is excellent in shape stability in high-temperature high-humidity environments and in surface hardness and usable for a transparent substrate material or protection material. A synthetic resin laminate includes a substrate layer containing a polycarbonate (B); and a resin layer laminated on one or both surfaces of the substrate layer, the resin layer containing a resin (A) that contains a (meth)acrylate copolymer (a1) and a polycarbonate (a2); wherein (a1) is a (meth)acrylate copolymer composed of 5 to 80% by mass of an aromatic (meth)acrylate unit (a11) and 20 to 95% by mass of a methyl methacrylate unit (a12); (a2) is a polycarbonate containing a constituent unit represented by formula [1]; and the ratio of (a1) with respect to the resin (A) is 5 to 55% by mass, and the ratio of (a2) with respect to the resin (A) is 95 to 45% by mass.

Claims

1. A synthetic resin laminate, which is obtained by laminating a resin layer containing a resin (A) that contains a (meth)acrylate copolymer (a1) and a polycarbonate (a2) on one surface or both surfaces of a substrate layer containing a polycarbonate (B), wherein the (meth)acrylate copolymer (a1) is a (meth)acrylate copolymer composed of 5 to 80% by mass of an aromatic (meth)acrylate unit (a11) and 20 to 95% by mass of a methyl methacrylate unit (a12), the ratio of the (meth)acrylate copolymer (a1) with respect to the resin (A) is 5 to 55% by mass, and the ratio of the polycarbonate (a2) with respect to the resin (A) is 95 to 45% by mass and the polycarbonate (a2) is a polycarbonate homopolymer or copolymer consisting of 20 to 100% by mass of a constituent unit represented by the following formula [2]: ##STR00007## and 80 to 0% by mass of a constituent unit represented by the following formula [3]: ##STR00008##

2. The synthetic resin laminate according to claim 1, wherein the resin (A) is composed of 5 to 55% by mass of the (meth)acrylate copolymer (a1) having a weight-average molecular weight of 5,000 to 30,000 and 95 to 45% by mass of the polycarbonate (a2) having a weight-average molecular weight of 21,000 to 40,000.

3. The synthetic resin laminate according to claim 1, wherein the resin layer containing the resin (A) has a thickness of 10 to 250 m, the synthetic resin laminate has a total thickness of 0.1 to 2.0 mm, and the thickness ratio of the resin layer/synthetic resin laminate is 0.01 to 0.5.

4. The synthetic resin laminate according to claim 1, wherein the polycarbonate (B) has a weight-average molecular weight of 18,000 to 40,000.

5. The synthetic resin laminate according to claim 1, wherein the resin layer and/or the substrate layer contains an ultraviolet absorber.

6. The synthetic resin laminate according to claim 1, wherein the resin layer containing the resin (A) is hard-coated.

7. The synthetic resin laminate according to claim 1, wherein the resin layer containing the resin (A) is provided on only one surface of the substrate layer containing the polycarbonate (B), and the resin layer containing the resin (A) and the substrate layer containing the polycarbonate (B) are hard-coated.

8. The synthetic resin laminate according to claim 1, wherein one surface or both surfaces of the synthetic resin laminate is obtained as a result of at least one of a reflection preventive treatment, an antifouling treatment, an anti-fingerprint treatment, an antistatic treatment, a climate-proof treatment, and an anti-glare treatment.

9. A transparent substrate material, comprising the synthetic resin laminate according to claim 1.

10. A transparent protection material, comprising the synthetic resin laminate according to claim 1.

Description

EXAMPLES

(1) Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples in any way.

(2) The properties of laminate resins obtained in production examples were measured as follows, and synthetic resin laminates obtained in examples and comparative examples were evaluated as follows.

(3) <Weight-Average Molecular Weight>

(4) Standard polystyrene was dissolved in chloroform and subjected to measurement performed by gel permeation chromatography (GPC) in advance. The resultant standard curve was used as the reference. A (meth)acrylate copolymer and a polycarbonate resin were subjected to measurement performed by GPC in a similar manner. By comparing the results, the weight-average molecular weights of the (meth)acrylate copolymer and the polycarbonate resin were calculated. The GPC device used was as follows.

(5) Device: Wates 2690

(6) Column: Shodex GPC KF-805L; 8300 mm; two coupled columns

(7) Developing solvent: chloroform

(8) Flow rate: 1 ml/min.

(9) Temperature: 30 C.

(10) Detector: UV . . . 486 nm polycarbonate RI . . . special acrylic resin
<Water Absorption Ratio>

(11) In conformity with the JIS-K7209 A method, the water absorption ratio was measured. First, test pieces having a size of 60 mm60 mm1.0 mm were created by press molding. The test pieces were put into an oven of 50 C. to be dried. 24 hours later, the test pieces were taken out from the oven and cooled in a desiccator adjusted to have a temperature of 23 C. One hour later, the weight of each test piece was measured, and then the test pieces were put into water of 23 C. 24 hours later, the test pieces were taken out from the water, moisture on the surface of each test piece was wiped out, and then the weight of each test piece was measured. Regarding each test piece, the difference between the weight after the test piece was put into the water and the weight immediately after the test piece was dried was obtained, and the different was divided by the weight immediately after the test piece was dried. The resultant value was multiplied by 100. In this manner, the water absorption ratio was found.

(12) <High-Temperature High-Humidity Exposure Test>

(13) Each of test pieces was cut out to have a size of 106 cm. The test piece was set in a holder supported at two positions, and kept in an environmental tester, set to a temperature of 23 C. and a relative humidity of 50%, for 24 hours to be adjusted in terms of the state. Then, warp was measured (pre-treatment warping amount). Next, the test piece was set in the holder, put into an environmental tester set to a temperature of 85 C. and a relative humidity of 85%, and kept for 120 hours in this state. The holder accommodating the test piece was moved into an environmental tester set to a temperature of 23 C. and a relative humidity of 50%, and kept for 4 hours in this state. Then, the warp was measured again (post-treatment warping amount). The warp was measured as follows. The test piece taken out from the holder was kept still in a horizontal state with a protruding part directed upward and scanned at an interval of 1 mm by use of a three-dimensional shape meter equipped with an electric stage. The protruding part at the center was measured as warp. The value of (post-treatment warping amount)(pre-treatment warping amount) was set as the shape stability.

(14) <Pencil Hardness Test>

(15) In conformity with JIS K 5600-5-4, a pencil was pressed to a surface of the resin (A) at an angle of 45 degree with respect to the surface and at a load of 750 g. The hardness of the pencil was gradually increased. The maximum hardness of the pencil which did not leave a scratch was set as the pencil hardness.

Synthesis Example 1

Production of Polycarbonate (a2)

Synthesis of copolymer polycarbonate of 2,2-bis(4-hydroxyl-3-methylphenyl)propane/2,2-bis(4-hydroxylphenyl)propane=6/4

(16) 6174.7 g (24.12 mol) of 2,2-bis(4-hydroxyl-3-methylphenyl)propane (produced by Honshu Chemical Industry Co., Ltd.), 4086 g (17.98 mol) of 2,2-bis(4-hydroxylphenyl)propane (produced by Nippon Steel Chemical Co., Ltd.; hereinafter, referred to simply as BPA), 3.8 g of triethylbenzyl ammonium chloride, and 50.0 g of hydrosulfite were dissolved in 54.5 L of aqueous solution of 9.0 w/w % sodium hydroxide.

(17) 24 L of methylene chloride was added to the resultant substance while being stirred, and 5390 g of phosgene was blown thereinto over 40 minutes while the temperature was kept at 15 C.

(18) After the process of blowing phosgene was finished, 190 g of p-t-butylphenol was added and vigorously stirred to emulsify the reaction liquid. After the emulsification, 110 ml of triethylamine was added, and the substances were stirred for about one hour at a temperature of 20 to 25 C. to cause polymerization.

(19) After the polymerization process was finished, the reaction liquid was divided into a water phase and an organic phase. The organic phase was neutralized with phosphoric acid, and was washed with water repeatedly until the conductivity of the previous liquid (water phase) was decreased down to 10 S/cm or less. The resultant polymer solution was dripped into warm water kept at 62 C., and the solvent was evaporated to be removed. Thus, a white powdery precipitate was obtained. The obtained precipitate was filtrated and dried at 120 C. for 24 hours. As a result, the intended polycarbonate polymer powder composed of 60% by mass of the constituent unit represented by formula [2] and 40% by mass of the constituent unit represented by formula [3] was obtained. The weight-average molecular weight of the resultant polycarbonate was 33,000.

Production Example 1

Production of Resin (a11) Pellet

(20) 40% by mass of Metablen H-880 (produced by Mitsubishi Rayon Co., Ltd.; weight-average molecular weight: 14,000; a11/a12=33/66) as the (meth)acrylate copolymer (a1) and 60% by mass of the polycarbonate polymer of synthesis example 1 were put into a blender and mixed for 20 minutes. Then, the mixture was melt and kneaded at a cylinder temperature of 260 C. by use of a biaxial extruder having a screw diameter of 35 mm. The resultant substance was extruded into a strand and pelletized by a pelletizer. Pellets were produced stably.

Production Example 2

Production of Resin (a12) Pellet

(21) 25% by mass of the (meth)acrylate copolymer used in production example 1 and 75% by mass of the polycarbonate polymer of synthesis example 1 were mixed and pelletized. The pelletization was performed under substantially the same conditions as those of production example 1. Pellets were produced stably.

Production Example 3

Production of Photocurable Resin Composition (F1) to be Used to Coat the High Hardness Layer

(22) A composition of 60 parts by mass of tris(2-acroxyethyl)isocyanurate (produced by Aldrich), 40 parts by mass of neopentylglycololigoacrylate (produced by Osaka Organic Chemical Industry Ltd.; trade name: 215D), 1 part by mass of 2,4,6-trimethylbenzoyldiphenylphosphineoxide (produced by Ciba Japan K.K.; trade name: DAROCUR TPO), 0.3 parts by mass of 1-hydroxycyclohexylphenylketone (produced by Aldrich), and 1 part by mass of 2-(2H-benzotriazole-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (produced by Ciba Japan K.K.; trade name: TINUVIN 234) was introduced into a mixing bath equipped with a stirring blade, and stirred for 1 hour while being kept at 40 C. As a result, a photocurable resin composition (F1) was obtained.

Production Example 4

Production of Photocurable Resin Composition (F2) to be Used to Coat the Substrate Layer

(23) A composition of 40 parts by mass of 1,9-nonanedioldiacrylate (produced by Osaka Organic Chemical Industry Ltd.; trade name: Biscoat #260), 40 parts by mass of hexafunctional urethane acrylate oligomer (produced by Shin-Nakamura Chemical Co., Ltd.; trade name: U-6HA), 20 parts by mass of condensate containing succinic acid/trimethylolethane/acrylic acid at a molar ratio of 1/2/4, 2.8 parts by mass of 2,4,6-trimethylbenzoyldiphenylphosphineoxide (produced by Ciba Japan K.K.; trade name: DAROCUR TPO), 1 part by mass of benzophenone (produced by Aldrich), and 1 part by mass of 2-(2H-benzotriazole-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (produced by Ciba Japan K.K.; trade name: TINUVIN 234) was introduced into a mixing bath equipped with a stirring blade, and stirred for 1 hour while being kept at 40 C. As a result, a photocurable resin composition (F2) was obtained.

Comparative Production Example 1

Production of Resin (A2) Pellet

(24) Only the polycarbonate (a2) of synthesis example 1 was used to produce pellets. The pelletization was performed in substantially the same manner as in production example 1. Pellets were produced stably.

Example 1

(25) A synthetic resin laminate was produced by use of a multi-layer extrusion device including a monoextruder having a shaft diameter of 40 mm, a monoextruder having a shaft diameter of 75 mm, and a multi-manifold die coupled to the extruders. The resin (A11) obtained in production example 1 was continuously introduced into the monoextruder having a shaft diameter of 40 mm and extruded under the conditions of a cylinder temperature of 240 C. and a dispensing rate of 4.0 kg/h. A polycarbonate resin (B1) (produced by Mitsubishi Engineering-Plastics Corporation; trade name: Iupilon S-1000; weight-average molecular weight: 33,000) was continuously introduced into the monoextruder having a shaft diameter of 75 mm and extruded under the conditions of a cylinder temperature of 270 C. and a dispensing rate of 63.0 kg/h. The resins extruded from the extruders were laminated in the multi-manifold and extruded from the T-die in the form of a sheet. Three mirror-finish rolls respectively having temperatures of 130 C., 120 C. and 190 C. from the upstream side were provided. The sheet was cooled while the mirror surfaces of the mirror-finish rolls were transferred thereto. As a result, a laminate (E1) of (A11) and (B1) was obtained. The resultant laminate had a total thickness of 1.0 mm, and the layer formed of (A11) had a thickness of 60 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 9 m, and the result of the pencil hardness test was 2H.

Example 2

(26) A laminate (E2) of (A11) and (B1) was obtained in substantially the same manner as in example 1 except that the dispensing rate of the monoextruder having a shaft diameter of 40 mm was 7.0 kg/h and that the dispensing rate of the monoextruder having a shaft diameter of 75 mm was 60.0 kg/h. The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A11) had a thickness of 110 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 14 m, and the result of the pencil hardness test was 2H.

Example 3

(27) The photocurable resin composition (F1) obtained in production example 3 was applied to the high hardness layer formed of (A11), in the laminate (E1) obtained in example 1, by use of a bar coater such that the post-curing thickness of the photocurable resin composition (F1) would be 3 to 8 m. The resultant substance was coated with a PET film pressure-contacted thereto. The photocurable resin composition (F2) obtained in production example 4 was applied to the substrate layer formed of (B1) by use of a bar coater such that the post-curing thickness of the photocurable resin composition (F2) would be 3 to 8 m. The resultant substance was coated with a PET film pressure-contacted thereto. The resultant laminate was irradiated and thus cured with ultraviolet rays under the condition of a line speed of 1.5 m/min. by use of a conveyor equipped with a high voltage mercury lamp having a light source distance of 12 cm and an output of 80 W/cm. Thus, the PET films were delaminated. As a result, a laminate (E3) in which the high hardness layer and the substrate layer were respectively coated with the hard-coats formed of (F1) and (F2) was obtained. The result of the high-temperature high-humidity exposure test was 9 m, and the result of the pencil hardness test was 4H.

Example 4

(28) A laminate (E4) of (A12) and (B1) was obtained in substantially the same manner as in example 1 except that the resin (A12) was used instead of the resin (A11). The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A12) had a thickness of 60 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 40 m, and the result of the pencil hardness test was H.

Example 5

(29) A laminate (E5) of (A12) and (B1) was obtained in substantially the same manner as in example 4 except that the dispensing rate of the monoextruder having a shaft diameter of 40 mm was 7.0 kg/h and that the dispensing rate of the monoextruder having a shaft diameter of 75 mm was 60.0 kg/h. The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A12) had a thickness of 110 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 47 m, and the result of the pencil hardness test was H.

Comparative Example 1

(30) A laminate (E6) of (A2) and (B1) was obtained in substantially the same manner as in example 1 except that the resin (A2) was used instead of the resin (A12). The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A2) had a thickness of 60 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 34 m, and the result of the pencil hardness test was F.

Comparative Example 2

(31) A laminate (E7) of (A2) and (B1) was obtained in substantially the same manner as in comparative example 1 except that the dispensing rate of the monoextruder having a shaft diameter of 40 mm was 7.0 kg/h and that the dispensing rate of the monoextruder having a shaft diameter of 75 mm was 60.0 kg/h. The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A2) had a thickness of 110 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 27 m, and the result of the pencil hardness test was F.

Comparative Example 3

(32) A laminate (E8) of (A3) and (B2) was obtained in substantially the same manner as in example 1 except that a methylmethacrylate-styrene copolymer (A3) (produced by Nippon Steel Chemical Co., Ltd.; trade name: MS600) was used instead of the resin (A11), that a polycarbonate (B2) (produced by Mitsubishi Engineering-Plastics Corporation; trade name; Iupilon S-3000; mass-average molecular weight: 27,000) was used instead of the polycarbonate (B1), that the cylinder temperature of the monoextruder having a shaft diameter of 32 mm was 220 C., and that the temperatures of the rolls were 130 C., 140 C. and 190 C. from the upstream side. The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A3) had a thickness of 60 m in a central part thereof. A laminate (E9) in which the high hardness layer and the substrate layer of the laminate (E8) were respectively coated with hard-coats formed of (F1) and (F2) was obtained in substantially the same manner as in example 3. The result of the high-temperature high-humidity exposure test was 400 m, and the result of the pencil hardness test was 3H.

Comparative Example 4

(33) A laminate (E10) of (A4) and (B1) was obtained in substantially the same manner as in example 1 except that a polymethylmethacrylate resin (A4) (produced by ARKEMA; trade name: ALTUGLAS V020) was used instead of the resin (A11) and that the temperatures of the rolls were 130 C., 130 C. and 190 C. from the upstream side. The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A4) had a thickness of 60 m in a central part thereof. The result of the high-temperature high-humidity exposure test was 1020 m, and the result of the pencil hardness test was 3H.

Comparative Example 5

(34) A laminate (E11) of (A4) and (B2) was obtained in substantially the same manner as in comparative example 4 except that the polycarbonate (B2) was used instead of the polycarbonate (B1). The resultant laminate had a total thickness of 1.0 mm, and the high hardness layer formed of (A4) had a thickness of 60 pun in a central part thereof. The result of the high-temperature high-humidity exposure test was 1030 m, and the result of the pencil hardness test was 3H.

Comparative Example 6

(35) A laminate (E12) in which the high hardness layer formed of (A4) and the substrate layer formed of (B2) in the laminate (E11) obtained in comparative example 5 were respectively coated with hard-coats formed of (F1) and (F2) was obtained in substantially the same manner as in example 3. The result of the high-temperature high-humidity exposure test was 1200 m, and the result of the pencil hardness test was 4H.

(36) As can be seen from the examples and the comparative examples, a resin laminate according to the present invention, in which a resin layer (high hardness layer) that contains a polycarbonate containing a constituent unit represented by formula [2] above and also contains a specific (meth)acrylate copolymer is laminated on a polycarbonate substrate layer, is superior in surface hardness and size stability in high-temperature high-humidity environments than resin laminates in comparative examples in which a polycarbonate resin containing the constituent unit represented by formula [2] above is laminated on a polycarbonate substrate layer. In addition, the resin laminate according to the present invention is superior in shape stability in high-temperature high-humidity environments than resin laminates in comparative examples in which a (meth)acrylate copolymer is laminated on a polycarbonate substrate layer.

(37) As can seen from Tables 1 and 2, a synthetic resin laminate according to the present invention is excellent in shape stability in high-temperature high-humidity environments, surface hardness, impact resistance, climate resistance and heat resistance.

(38) TABLE-US-00001 TABLE 1 Water absorption ratio/% Produced (Meth)acrylate JIS K 7209 Pellet resin copolymer (a1) Polycarbonate (a2) 24 hr. in production Example Symbol [Mass %] [Mass %] 23 C. water Possible Production A11 Metablen H-880 Copolymer of 2,2-bis(4-hydroxy-3- 0.33% Possible example 1 [40%] methylphenyl)propane/2,2-bis(4- hydroxyphenyl)propane = 6/4 [60%] Production A12 Metablen H-880 Copolymer of 2,2-bis(4-hydroxy-3- 0.28% Possible example 2 [25%] methylphenyl)propane/2,2-bis(4- hydroxyphenyl)propane = 6/4 [75%] Comparative A2 Copolymer of 2,2-bis(4-hydroxy-3- 0.2% Possible production methylphenyl)propane/2,2-bis(4- example 1 hydroxyphenyl)propane = 6/4 [100%] Reference A3 Methylmethacrylate-styrene copolymer: MS600 0.51% Commecially example 1 available Reference A4 Poly(methyl methacrylate): V020 0.80% Commecially example 2 available Reference B1 Polycarbonate: Iupilon S-1000 0.29% Commecially example 3 available Reference B2 Polycarbonate: Iupilon S-3000 0.29% Commecially example 4 available

(39) TABLE-US-00002 TABLE 2 (A) (B) Shape stability in (A) material material (A) (B) high-temperature high- surface [thickness] [thickness] surface surface humidity environments pencil Example m m hard-coat hard-coat Laminate [Shape change amount/m] hardness Example 1 A11 [60] B1 [940] None None E1 9 m 2H Example 2 A11 [110] B1 [890] None None E2 14 m 2H Example 3 A11 [60] B1 [940] F1 F2 E3 9 m 4H Example 4 A12 [60] B1 [940] None None E4 40 m H Example 5 A12 [110] B1 [890] None None E5 47 m H Comparative A2 [60] B1 [940] None None E6 34 m F example 1 Comparative A2 [110] B1 [890] None None E7 27 m F example 2 Comparative A3 [60] B2 [940] F1 F2 E9 400 m 3H example 3 Comparative A4 [60] B1 [940] None None E10 1020 m 3H example 4 Comparative A4 [60] B2 [940] None None E11 1030 m 3H example 5 Comparative A4 [60] B2 [940] F1 F2 E12 1200 m 4H example 6

INDUSTRIAL APPLICABILITY

(40) A synthetic resin laminate according to the present invention has a feature of being excellent in shape stability in high-temperature high-humidity environments, surface hardness, impact resistance, climate resistance and heat resistance, and is preferably usable as a transparent substrate material, a transparent protection material or the like, especially for front plates of display sections of information appliances and mobile electronic devices, substrates of touch panels and sheets for heat bending.