RESIN SHEET FOR HIGH HARDNESS MOLDING AND MOLDED ARTICLE USING SAME

Abstract

Provided is a resin sheet for molding, which is provided with a base material layer that contains a polycarbonate resin (a1), a high hardness resin layer that contains a high hardness resin, and a hard coat anti-glare layer, and which is configured such that: the high hardness resin layer is arranged between the base material layer and the hard coat anti-glare layer; the glass transition points of the polycarbonate resin (a1) and the high hardness resin satisfy the relational expression −10° C.≤(glass transition point of high hardness resin)−(glass transition point of polycarbonate resin (a1))≤40° C.; and two protective films are superposed and bonded onto both surfaces of the resin sheet.

Claims

1. A resin sheet for molding, which comprises: a base material layer that contains a polycarbonate resin (a1); a high hardness resin layer that contains a high hardness resin; and a hard coat anti-glare layer, wherein: the high hardness resin layer is arranged between the base material layer and the hard coat anti-glare layer; glass transition points of the polycarbonate resin (a1) and the high hardness resin satisfy the following relational expression:
−10° C.≤(glass transition point of high hardness resin)−(glass transition point of polycarbonate resin (a1))<40° C.; and two protective films are superposed and bonded onto both surfaces of the resin sheet, respectively.

2. The resin sheet for molding according to claim 1, wherein the polycarbonate resin (a1) is an aromatic polycarbonate resin.

3. The resin sheet for molding according to claim 2, wherein the aromatic polycarbonate resin comprises a structural unit represented by general formula (4a): ##STR00018##

4. The resin sheet for molding according to claim 1, wherein a content of the polycarbonate resin (a1) is 75 to 100% by mass relative to the total mass of the base material layer.

5. The resin sheet for molding according to claim 1, wherein the high hardness resin is selected from the group consisting of Resin (B1) to Resin (B5) below: Resin (B1): a copolymer containing a (meth)acrylic acid ester structural unit (a) represented by general formula (1) below: ##STR00019## (wherein R1 represents a hydrogen atom or a methyl group, and R2 represents a C.sub.1-C.sub.18 alkyl group), and an aliphatic vinyl structural unit (b) represented by general formula (2) below: ##STR00020## (wherein R3 represents a hydrogen atom or a methyl group, and R4 is a cyclohexyl group which may be substituted with a C.sub.1-C.sub.4 hydrocarbon group); or an alloy of the copolymer and Resin (B2); Resin (B2): a copolymer (D) containing 6 to 77% by mass of a (meth)acrylic acid ester structural unit, 15 to 71% by mass of a styrene structural unit and 8 to 23% by mass of an unsaturated dicarboxylic acid structural unit, or an alloy of the copolymers (D), or an alloy of the copolymer (D) and another high hardness resin, or an alloy of the copolymer (D) and an acrylic resin; Resin (B3): a copolymer containing a structural unit (c) represented by general formula (6) below: ##STR00021## and optionally a structural unit (d) represented by general formula (7) below: ##STR00022## Resin (B4): a copolymer (G) containing 5 to 20% by mass of a styrene structural unit, 60 to 90% by mass of a (meth)acrylic acid ester structural unit and 5 to 20% by mass of an N-substituted maleimide structural unit, or an alloy of the copolymer (G) and the aforementioned Resin (B2); Resin (B5): a resin containing a structural unit (e) represented by general formula (8) below: ##STR00023##

6. The resin sheet for molding according to claim 1, wherein a content of the high hardness resin is 70 to 100% by mass relative to the total mass of the high hardness resin layer.

7. The resin sheet for molding according to claim 1, wherein a total thickness of the base material layer and the high hardness resin layer is 0.5 mm to 3.5 mm.

8. The resin sheet for molding according to claim 1, wherein a ratio of the thickness of the base material layer in the total thickness of the base material layer and the high hardness resin layer is 75% to 99%.

9. The resin sheet for molding according to claim 1, which has a haze of 2 to 30%.

10. The resin sheet for molding according to claim 1, wherein a pencil hardness of the surface of the hard coat anti-glare layer of the resin sheet for molding is 2H or harder.

11. The resin sheet for molding according to claim 1, wherein, regarding the two superposed and bonded protective films of the resin sheet for molding, when one that is in contact with the resin sheet is referred to as a first protective film and the other at the outer side is referred to as a second protective film, the first protective film is composed of a polyolefin-based film having a melting point of 100 to 130° C., and the second protective film is composed of a polyolefin-based film having a melting point of 140° C. or higher.

12. The resin sheet for molding according to claim 1, wherein, regarding the two superposed and bonded protective films of the resin sheet for molding, when one that is in contact with the resin sheet is referred to as a first protective film and the other at the outer side is referred to as a second protective film, the first protective film is composed of a polyolefin-based film having a melting point of 100 to 130° C., and the second protective film is composed of a PET-based protective film.

13. A resin molded article obtained by molding the resin sheet for molding according to claim 1.

Description

EXAMPLES

[0188] Hereinafter, working examples of the present invention will be described, but the present invention is not limited to embodiments of the working examples.

<Measurement of Glass Transition Point (Tg) and Melting Point>

[0189] Using a differential scanning calorimeter DSC7020 manufactured by Hitachi High-Tech Science Corporation, the glass transition point of each of the polycarbonate resins and high hardness resins used in the Examples and Comparative Examples and the melting point of each of the protective films were measured at a temperature raising rate of 10° C./min under nitrogen atmosphere. The weight of each resin used in the measurement was 10 to 20 mg.

<Measurement of Pencil Hardness of Resin Sheet>

[0190] Each of the resin sheets produced in the Examples and Comparative Examples was evaluated by the pencil scratch hardness test in accordance with JIS K 5600-5-4. The highest hardness of the pencil, with which the surface of the hard coat anti-glare layer was not damaged when the pencil was pressed against the surface at an angle of 45° with respect to the surface with a load of 750 g, while increasing the hardness thereof, was evaluated as the pencil hardness. The hardness of 2H or harder was evaluated as acceptable.

<Production of Molded Article Having Curved Shape and Evaluation of Crack of Hard Coat after Molding>

[0191] The resin sheets produced in the Examples and Comparative Examples were subjected to thermoforming. Regarding Examples 1-3 and 5-13 and Comparative Examples 1-5 and 7-10, molds for hot pressing with a clearance (gap between an upper mold and a lower mold for sandwiching a sheet for molding) of 2 mm and a molding R of 50 mm were used, and regarding Example 4 and Comparative Example 6, molds for hot pressing with a clearance of 3.5 mm and a molding R of 100 mm were used. The pressure applied to the molds for hot pressing was 0.6 MPa. The material of the molds was aluminum. The mold temperature at the time of thermoforming was 124° C. in Examples 1-5, 7-11 and 13 and Comparative Examples 1-3, 8 and 9, and 143° C. in Examples 6 and 12 and Comparative Examples 4-7 and 10.

[0192] Regarding the obtained molded articles, the presence or absence of a crack in the 50 mm R portion or 100 mm R portion was confirmed. Note that when a resin sheet in which the total thickness of the base material layer and the high hardness resin layer is 0.5 mm, 1.2 mm or 1.5 mm was formed using the molds for hot pressing with the clearance of 2 mm, a single-layer polycarbonate sheet of 1.5 mm, 0.8 mm or 0.5 mm was laid under it to adjust the total thickness to be 2 mm, thereby performing hot press molding.

<Flow Mark>

[0193] Regarding each layered body of the high hardness resin layer and the polycarbonate resin layer before hard-coated produced in the Examples and Comparative Examples, outer appearance thereof was visually examined under a three-wavelength fluorescent lamp to confirm the presence or absence of a scaly pattern and white turbidity. The case where none of scaly pattern and white turbidity was observed was evaluated as “flow mark is absent”, and the case where a scaly pattern or white turbidity was observed was evaluated as “flow mark is present”.

<Transfer of Mold Scratch>

[0194] The first protective film and the second protective film were peeled off from each hot-press-molded article of the resin sheet for molding produced in the Examples and Comparative Examples, and outer appearance thereof was visually examined under a three-wavelength fluorescent lamp to confirm the presence or absence of transfer of a mold scratch to the resin sheet.

<Fusion Bonding of Protective Film>

[0195] After each of the resin sheets for molding produced in the Examples and Comparative Examples was subjected to hot press molding, the presence or absence of fusion bonding of the protective film to the mold or resin sheet was visually confirmed. In the case where the protective film was fusion-bonded to the mold, it is a defect because it is required to peel off the film to clean the mold before the next hot press molding. In the case where the protective film was fusion-bonded to the resin sheet, it is a defect because peeling failure of the first protective film and the second protective film is caused.

<Measurement of Haze of Resin Sheet>

[0196] Evaluation was made in accordance with JIS K 7136 using an HR-100 type manufactured by Murakami Color Research Laboratory Co., Ltd.

Example 1: R100 (Tg: 124° C.)/Low Tg PC (Tg: 125° C.)/1.2 mmt

[0197] A layered body consisting of a base material layer and a high hardness resin layer was formed using a multilayer extrusion apparatus having a single screw extruder with a screw diameter of 35 mm, a single screw extruder with a screw diameter of 65 mm, a feed block connected to the respective extruders and a T-die connected to the feed block. Specifically, a high hardness resin (B2) (copolymer containing 21% by mass of a methyl methacrylate structural unit, 64% by mass of a styrene structural unit and 15% by mass of a maleic anhydride structural unit; RESISFY R100 (manufactured by Denka)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 50.0 kg/hour.

[0198] The extruded high hardness resin and the extruded polycarbonate resin were introduced into the feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 240° C. It was further introduced into the T-die at 240° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0199] A hard coat anti-glare layer was formed on the high hardness resin layer side of the layered body obtained above. The material of the hard coat anti-glare layer is as described below.

Relative to 100 parts by mass of a mixture containing:

[0200] U6HA: hexafunctional urethane acrylate oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd.), 60% by mass;

[0201] 4EG-A: PEG200 # diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.), 35% by mass; and

[0202] RS-90: fluorine-containing group/hydrophilic group/lipophilic group/UV reactive group-containing oligomer (manufactured by DIC), 5% by mass,

[0203] Photopolymerization initiator: 1-184 (manufactured by BASF [compound name: 1-hydroxy-cyclohexyl phenyl ketone]), 1 part by mass

[0204] The above-described material was applied to the layered body using a bar coater, the concave-convex surface of a frosted glass plate having a haze of 10% and a thickness of 2 mm was attached thereon, and it was irradiated with a metal halide lamp (20 mW/cm.sup.2) from above the glass plate for 5 seconds to cure the hard coat. After the hard coat anti-glare layer was bonded, the frosted glass plate was removed, thereby preparing a resin sheet. The thickness of the hard coat anti-glare layer was 6 μm. The haze of the resin sheet was 9%.

[0205] MX-318N manufactured by Nihon Matai Co., Ltd. (melting point: 121° C., 161° C.) was placed on both the surfaces of the above-described resin sheet, and it was pressure-bonded (load: 5 kg/cm.sup.2) between 2 rubber rolls at room temperature to bond the first protective film. Next, L-3330 manufactured by Hitachi Chemical Co., Ltd. (melting point: 164° C.) was placed on both the surfaces, and it was pressure-bonded between the rubber rolls in the same manner to bond the second protective film, thereby obtaining a resin sheet for molding.

Example 2: R100 (Tg: 124° C.)/Low Tg PC (Tg: 125° C.)/2 mmt

[0206] A resin sheet for molding was prepared in a manner similar to that in Example 1, except that the discharge rate at the time of extrusion of the polycarbonate resin with the single screw extruder was adjusted to 83.0 kg/hour and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 2 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Example 3: R100 (Tg: 124° C.)/Low Tg PC (Tg: 125° C.)/0.5 mmt

[0207] A resin sheet for molding was prepared in a manner similar to that in Example 1, except that the discharge rates at the time of extrusion of the high hardness resin (B2) and the polycarbonate resin with the single screw extruders were adjusted to 4.8 kg/hour and 35.0 kg/hour, respectively, and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 0.5 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Example 4: R100 (Tg: 124° C.)/Low Tg PC (Tg: 125° C.)/3.5 mmt

[0208] A resin sheet for molding was prepared in a manner similar to that in Example 1, except that the discharge rates at the time of extrusion of the high hardness resin (B2) and the polycarbonate resin with the single screw extruders were adjusted to 1.3 kg/hour and 72.0 kg/hour, respectively, and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 3.5 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Example 5: R310 (Tg: 141° C.)/Low Tg PC (Tg: 125° C.)/2 mmt

[0209] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B2) (copolymer containing 6% by mass of a methyl methacrylate structural unit, 71% by mass of a styrene structural unit and 23% by mass of a maleic anhydride structural unit; RESISFY R310 (manufactured by Denka)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 83.0 kg/hour.

[0210] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0211] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0212] MX-217Y manufactured by Nihon Matai Co., Ltd. (melting point: 106° C., 124° C.) was placed on both the surfaces of the above-described resin sheet, and it was pressure-bonded (load: 5 kg/cm.sup.2) between 2 rubber rolls at room temperature to bond the first protective film. Next, #40-R200A manufactured by Toray Advanced Film Co., Ltd. (melting point: 148° C.) was placed on both the surfaces, and it was pressure-bonded between the rubber rolls in the same manner to bond the second protective film, thereby obtaining a resin sheet for molding.

Example 6: R310 (Tg: 141° C.)/S-1000 (Tg: 147° C.)/2 mmt

[0213] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B2) (copolymer containing 6% by mass of a methyl methacrylate structural unit, 71% by mass of a styrene structural unit and 23% by mass of a maleic anhydride structural unit; RESISFY R310 (manufactured by Denka)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupilon S-1000; manufactured by Mitsubishi Engineering-Plastics Corporation) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 280° C. and a discharge rate of 83.0 kg/hour.

[0214] The extruded high hardness resin and the extruded polycarbonate resin were introduced into a feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 280° C. It was further introduced into the T-die at 280° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 m.

[0215] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0216] The first protective film and the second protective film were bonded in a manner similar to that in Example 5.

Example 7: PM-120N (Tg: 120° C.)/Low Tg PC (Tg: 125° C.)/1.5 mmt

[0217] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B4) (copolymer containing 7% by mass of a styrene structural unit, 86% by mass of a methyl methacrylate structural unit and 7% by mass of a N-phenylmaleimide structural unit; DELPET PM120N (manufactured by Asahi Kasei Chemicals Corporation)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 62.0 kg/hour.

[0218] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.5 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0219] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0220] E-MASK 100 manufactured by Nitto Denko Corporation (melting point: 109° C.) was placed on both the surfaces of the above-described resin sheet, and it was pressure-bonded (load: 5 kg/cm.sup.2) between 2 rubber rolls at room temperature to bond the first protective film. Next, #40-R200A manufactured by Toray Advanced Film Co., Ltd. (melting point: 148° C.) was placed on both the surfaces, and it was pressure-bonded between the rubber rolls in the same manner to bond the second protective film, thereby obtaining a resin sheet for molding.

Example 8: R200 (Tg: 126° C.)/Low Tg PC (Tg: 125° C.)/2 mmt

[0221] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B2) (copolymer containing 26% by mass of a methyl methacrylate structural unit, 55% by mass of a styrene structural unit and 19% by mass of a maleic anhydride structural unit; RESISFY R200 (manufactured by Denka)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 83.0 kg/hour.

[0222] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 m.

[0223] The material of the hard coat anti-glare layer was the same as Example 1. It was applied to the layered body using a bar coater, the concave-convex surface of a frosted glass plate having a haze of 30% and a thickness of 2 mm was attached thereon, and it was irradiated with a metal halide lamp (20 mW/cm.sup.2) from above the glass plate for 5 seconds to cure the hard coat. After the hard coat anti-glare layer was bonded, the frosted glass plate was removed, thereby preparing a resin sheet. The thickness of the hard coat anti-glare layer was 6 μm. The haze of the resin sheet was 29%.

[0224] The first protective film and the second protective film were bonded in a manner similar to that in Example 7.

Example 9: C-PC (KH3410UR) (Tg: 118° C.)/Low Tg PC (Tg: 125° C.)/2 mmt

[0225] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B3) (polycarbonate resin; Iupilon KH3410UR (manufactured by Mitsubishi Engineering-Plastics Corporation)) was continuously introduced and extruded at a cylinder temperature of 270° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (lupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 83.0 kg/hour.

[0226] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0227] A hard coat anti-glare layer was formed in a manner similar to that in Example 8.

[0228] The first protective film and the second protective film were bonded in a manner similar to that in Example 7.

Example 10: Alloy of R100 and PM120N (Tg: 123° C.)/Low Tg PC (Tg: 125° C.)/1.2 mmt

[0229] 75% by mass of a copolymer containing 21% by mass of a methyl methacrylate structural unit, 64% by mass of a styrene structural unit and 15% by mass of a maleic anhydride structural unit (RESISFY R100 (manufactured by Denka)) and 25% by mass of a copolymer containing 7% by mass of a styrene structural unit, 86% by mass of a methyl methacrylate structural unit and 7% by mass of a N-phenylmaleimide structural unit (DELPET PM120N; manufactured by Asahi Kasei Chemicals Corporation) were introduced into an extruder having a screw diameter of 26 mm (TEM-26SS, L/D≈40; manufactured by Toshiba Machine Co., Ltd.) and melt-kneaded at 240° C. to obtain a high hardness resin (B4).

[0230] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, the above-described high hardness resin (B4) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 50.0 kg/hour.

[0231] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0232] A hard coat anti-glare layer was formed in a manner similar to that in Example 8.

[0233] The first protective film and the second protective film were bonded in a manner similar to that in Example 7.

Example 11: R310 (Tg: 141° C.)/Low Tg PC (Tg: 125° C.)/0.5 mmt

[0234] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B2) (copolymer containing 6% by mass of a methyl methacrylate structural unit, 71% by mass of a styrene structural unit and 23% by mass of a maleic anhydride structural unit; RESISFY R310 (manufactured by Denka)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 8 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 35.0 kg/hour.

[0235] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body (Y2) was 0.5 mm, and the thickness of the high hardness resin layer near the center thereof was 100 μm.

[0236] The material of the hard coat anti-glare layer was the same as Example 1. It was applied to the layered body using a bar coater, the concave-convex surface of a frosted glass plate having a haze of 4% and a thickness of 2 mm was attached thereon, and it was irradiated with a metal halide lamp (20 mW/cm.sup.2) from above the glass plate for 5 seconds to cure the hard coat. After the hard coat anti-glare layer was bonded, the frosted glass plate was removed, thereby preparing a resin sheet. The thickness of the hard coat anti-glare layer was 6 μm. The haze of the resin sheet was 2%.

[0237] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Example 12: FPC0220 (Tg: 184° C.)/E2000 (147° C.)/1.2 mmt

[0238] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B5) (polycarbonate resin represented by general formula (8); Iupizeta FPC0220 (manufactured by Mitsubishi Gas Chemical Company, Inc.)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 300° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupilon E2000; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 280° C. and a discharge rate of 50.0 kg/hour.

[0239] The extruded high hardness resin and the extruded polycarbonate resin were introduced into a feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 280° C. It was further introduced into the T-die at 280° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0240] A hard coat anti-glare layer was formed in a manner similar to that in Example 11.

[0241] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Example 13: MS-H (Tg: 115° C.)/Low Tg PC (Tg: 125° C.)/1.2 mmt

[0242] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. A high hardness resin (B1) (resin, wherein in general formula (1), both R1 and R2 are a methyl group and in general formula (2), R3 is a hydrogen atom and R4 is a cyclohexyl group; consisting of 75 mol % of a (meth)acrylic acid ester structural unit and 25 mol % of an aliphatic vinyl structural unit, and having a weight average molecular weight of 120,000) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 50.0 kg/hour.

[0243] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0244] A hard coat anti-glare layer was formed in a manner similar to that in Example 11.

[0245] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Comparative Example 1: MS-H (Tg: 115° C.)/Low Tg PC (125° C.)/0.5 mmt

[0246] A layered body was prepared in a manner similar to that in Example 13, except that: the cylinder temperature and the discharge rate at the time of extrusion of the high hardness resin (B1) with the single screw extruder were adjusted to 230° C. and 8.0 kg/hour, respectively; the discharge rate at the time of extrusion of the polycarbonate resin with the single screw extruder was adjusted to 35.0 kg/hour; and the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 0.5 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

[0247] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0248] The first protective film and the second protective film were not bonded.

Comparative Example 2: Alloy of R100 and PMMA (Tg: 115° C.)/low Tg PC (Tg: 125° C.)/1.2 mmt

[0249] 75% by mass of a copolymer consisting of 21% by mass of a methyl methacrylate structural unit, 64% by mass of a styrene structural unit and 15% by mass of a maleic anhydride structural unit (RESISFY R100; manufactured by Denka) and 25% by mass of an acrylic resin (PARAPET HR-1000L (PMMA); manufactured by Kuraray Co., Ltd.) were introduced into an extruder having a screw diameter of 26 mm (TEM-26SS, L/D≈40; manufactured by Toshiba Machine Co., Ltd.) and melt-kneaded at 240° C. to obtain a high hardness resin (B2).

[0250] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, the above-described high hardness resin was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 230° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 50.0 kg/hour.

[0251] After that, extrusion with the T-die was carried out in a manner similar to that in Example 1, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0252] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0253] E-MASK 100 manufactured by Nitto Denko Corporation (melting point: 109° C.) was placed on both the surfaces of the above-described resin sheet, and it was pressure-bonded (load: 5 kg/cm.sup.2) between 2 rubber rolls at room temperature to bond the first protective film. The second protective film was not bonded.

Comparative Example 3

[0254] A layered body consisting of a high hardness resin layer and a polycarbonate resin layer (base material layer) was obtained in a manner similar to that in Example 1.

[0255] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0256] #40-R200A manufactured by Toray Advanced Film Co., Ltd. (melting point: 148° C.) was placed on both the surfaces of the above-described resin sheet, and it was pressure-bonded (load: 5 kg/cm.sup.2) between 2 rubber rolls at room temperature to bond the first protective film. The second protective film was not bonded.

Comparative Example 4: MS-H (Tg: 115° C.)/S1000 (Tg: 147° C.)/1.2 mmt

[0257] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B1) (resin, wherein in general formula (1), both R1 and R2 are a methyl group and in general formula (2), R3 is a hydrogen atom and R4 is a cyclohexyl group; consisting of 75 mol % of a (meth)acrylic acid ester structural unit and 25 mol % of an aliphatic vinyl structural unit, and having a weight average molecular weight of 120,000) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupilon S-1000; manufactured by Mitsubishi Engineering-Plastics Corporation) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 280° C. and a discharge rate of 50.0 kg/hour.

[0258] The extruded high hardness resin and the extruded polycarbonate resin were introduced into a feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 270° C. It was further introduced into the T-die at 270° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0259] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0260] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Comparative Example 5: MS-H (Tg: 115° C.)/S1000 (Tg: 147° C.)/2 mmt

[0261] A resin sheet for molding was prepared in a manner similar to that in Comparative Example 4, except that the discharge rate at the time of extrusion of the polycarbonate resin with the single screw extruder was adjusted to 83.0 kg/hour and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 2 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Comparative Example 6: MS-H (Tg: 115° C.)/S1000 (Tg: 147° C.)/3.5 mmt

[0262] A resin sheet for molding was prepared in a manner similar to that in Comparative Example 4, except that the discharge rates at the time of extrusion of the high hardness resin (B1) and the polycarbonate resin with the single screw extruders were adjusted to 1.3 kg/hour and 72.0 kg/hour, respectively, and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 3.5 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Comparative Example 7: MS-H (Tg: 115° C.)/S1000 (Tg: 147° C.)/0.5 mmt

[0263] A resin sheet for molding was prepared in a manner similar to that in Comparative Example 4, except that the discharge rates at the time of extrusion of the high hardness resin (B1) and the polycarbonate resin with the single screw extruders were adjusted to 4.8 kg/hour and 35.0 kg/hour, respectively, and that the thickness of the layered body of the high hardness resin layer and the polycarbonate resin layer (base material layer) was adjusted to 0.5 mm (the thickness of the high hardness resin layer near the center thereof was 60 μm).

Comparative Example 8: PMMA (Tg: 105° C.)/low Tg PC (Tg: 125° C.)/0.8 mmt

[0264] A layered body consisting of a base material layer and a high hardness resin layer was formed using a multilayer extrusion apparatus having a single screw extruder with a screw diameter of 32 mm, a single screw extruder with a screw diameter of 65 mm, a feed block connected to the respective extruders and a T-die connected to the feed block. Specifically, a high hardness resin (acrylic resin; PARAPET HR-1000L (PMMA); manufactured by Kuraray Co., Ltd.) was continuously introduced into the single screw extruder with the screw diameter of 32 mm and extruded at a cylinder temperature of 250° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 32.0 kg/hour.

[0265] The extruded high hardness resin and the extruded polycarbonate resin were introduced into the feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 240° C. It was further introduced into the T-die at 240° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 110° C., 140° C. and 185° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 0.8 mm, and the thickness of the high hardness resin layer near the center thereof was 60 μm.

[0266] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0267] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Comparative Example 9: FPC0220 (Tg: 184° C.)/T1380 (125° C.)/1.2 mmt

[0268] Using the same multilayer extrusion apparatus as Example 1, a layered body consisting of a base material layer and a high hardness resin layer was formed. Specifically, a high hardness resin (B5) (polycarbonate resin represented by general formula (8); Iupizeta FPC0220 (manufactured by Mitsubishi Gas Chemical Company, Inc.)) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 300° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (Iupizeta T-1380; manufactured by Mitsubishi Gas Chemical Company, Inc.) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 240° C. and a discharge rate of 50.0 kg/hour.

[0269] The extruded high hardness resin and the extruded polycarbonate resin were introduced into the feed block having a distribution pin for two types of two layers, and the high hardness resin and the polycarbonate resin were layered at 280° C. It was further introduced into the T-die at 280° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body consisting of the high hardness resin layer and the polycarbonate resin layer (base material layer). The thickness of the obtained layered body was 1.2 mm, and the thickness of the high hardness resin layer near the center thereof was 60 sm.

[0270] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0271] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

Comparative Example 10: S-1000 (Tg: 147° C.) alone/2 mmt

[0272] Instead of a high hardness resin, the same polycarbonate resin as that contained in a base material layer was used to form a layered body. As an extrusion apparatus, the same multilayer extrusion apparatus as Example 1 was used. Specifically, a polycarbonate resin (Iupilon S-1000 (manufactured by Mitsubishi Engineering-Plastics Corporation); pencil hardness: 3B) was continuously introduced into the single screw extruder with the screw diameter of 35 mm and extruded at a cylinder temperature of 280° C. and a discharge rate of 2.6 kg/hour. Further, a polycarbonate resin (lupilon S-1000; manufactured by Mitsubishi Engineering-Plastics Corporation) was continuously introduced into the single screw extruder with the screw diameter of 65 mm and extruded at a cylinder temperature of 280° C. and a discharge rate of 83.0 kg/hour.

[0273] The extruded polycarbonate resins were introduced into the feed block having a distribution pin for two types of two layers, and they were layered at 280° C. It was further introduced into the T-die at 280° C. to be extruded into a sheet shape, and using 3 mirror-finished rolls each at 120° C., 130° C. and 190° C. from the upstream side, it was transferred on the mirror surfaces and cooled, thereby obtaining the layered body of the polycarbonate resin. The thickness of the obtained layered body was 2 mm.

[0274] A hard coat anti-glare layer was formed in a manner similar to that in Example 1.

[0275] The first protective film and the second protective film were bonded in a manner similar to that in Example 1.

[0276] The resin sheets produced in the Examples and Comparative Examples were evaluated with respect to the hardness, the presence or absence of a crack after molding, and the presence or absence of a flow mark, transfer of a mold scratch and fusion bonding of a protective film. The results are shown in Table 1 below.

TABLE-US-00001 TABLE 1 Dif- Thick- Melting Melting ference ness Pencil point point Fusion TgB TgA in Tg of sheet hardness of first of second Crack Transfer bonding of *1 *2 (TgB- *3 of resin Haze protective protective afler Flow of mold protective (° C.) (° C.) TgA) (mm) sheet (%) film (° C.) film (° C.) molding mark scratch film Example 1 124 125  −1 1.2 2H  9 121, 161 164 Absent Absent Absent Absent Example 2 124 125  −1 2 2H  9 121, 161 164 Absent Absent Absent Absent Example 3 124 125  −1 0.5 2H  9 121, 161 164 Absent Absent Absent Absent Example 4 124 125  −1 3.5 2H  9 121, 161 164 Absent Absent Absent Absent Example 5 141 125  16 2 3H  9 106, 124 148 Absent Absent Absent Absent Example 6 141 147  −6 2 3H  9 106, 124 148 Absent Absent Absent Absent Example 7 120 125  −5 1.5 3H  9 109 148 Absent Absent Absent Absent Example 8 126 125  1 2 3H 29 109 148 Absent Absent Absent Absent Example 9 118 125  −7 2 4H 29 109 148 Absent Absent Absent Absent Example 10 123 125  −2 1.2 3H 29 109 148 Absent Absent Absent Absent Example 11 141 125  16 0.5 3H  2 121, 161 164 Absent Absent Absent Absent Example 12 184 147  37 1.2 2H  2 121, 161 164 Absent Absent Absent Absent Example 13 115 125 −10 1.2 3H  2 121, 161 164 Absent Absent Absent Absent Comparative 115 125 −10 0.5 3H  9 Absent Absent Absent Absent Present Absent Example 1 Comparative 115 125 −10 1.2 3H  9 109 Absent Absent Absent Absent Present Example 2 Comparative 124 125  −1 1.2 2H  9 148 Absent Absent Absent Present Absent Example 3 Comparative 115 147 −32 1.2 3H  9 121, 161 164 Present Absent Absent Absent Example 4 Comparative 115 147 −32 2 3H  9 121, 161 164 Present Absent Absent Absent Example 5 Comparative 115 147 −32 3.5 3H  9 121, 161 164 Present Absent Absent Absent Example 6 Comparative 115 147 −32 0.5 3H  9 121, 161 164 Present Absent Absent Absent Example 7 Comparative 105 125 −20 0.8 3H  9 121, 161 164 Present Absent Absent Absent Example 8 Comparative 184 125  59 1.2 2H  9 121, 161 164 Absent Present Absent Absent Example 9 Comparative — 147 — 2 HB  9 121, 161 164 Absent Absent Absent Absent Example 10 *1 “TgB” means Tg of the high hardness resin. *2 “TgA” means Tg of the polycarbonate resin. *3 “Thickness of sheet” means the total thickness of the base material layer and the high hardness resin layer.

[0277] It is understood that the resin sheet of the present invention has excellent hardness, does not have any flow mark, and does not have any abnormal appearance such as a crack after thermoforming.

[0278] The several embodiments of the present invention were described above, but these embodiments were presented as examples and it is not intended to limit the scope of the invention thereby. These novel embodiments can be practiced in other various modes and can be omitted, substituted or modified variously without departing from the gist of the present invention. These embodiments and modifications thereof are included in the scope or gist of the invention and also included in the scope of the inventions recited in the claims and equivalents thereof.