JP2014004747A - Thermoplastic resin laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic resin laminate excellent in impact resistance, heat resistance, low water absorption, and scratch resistance, and to provide a transparent resin plate for a display, including the thermoplastic resin laminate.SOLUTION: There are provided: the thermoplastic resin laminate including a thermoplastic resin layer (B) and a heat-resistant styrenic resin composition layer (A) which is laminated on one surface or both surfaces of the thermoplastic resin layer (B) and contains α-methylstyrene copolymer comprising α-methylstyrene and styrene and containing 5-70 wt.% of an α-methylstyrene constituent unit; and the transparent resin plate for a display, including the thermoplastic resin laminate.

Description

  The present invention relates to a thermoplastic resin laminate excellent in impact resistance, heat resistance, low water absorption, and scratch resistance, and a transparent resin plate for a display provided with the thermoplastic resin laminate.

  Resin-made transparent plates are used in a wide variety of applications, including sound barriers, carports, signboards, and front panels for office equipment and portable electronic devices. In particular, in the case of portable display devices such as mobile phone terminals, portable electronic play equipment, and PDAs, the front panel has impact resistance, heat resistance, weather resistance, low water absorption, and scratch resistance due to the functionality that the user carries around. There is an increasing demand for improvement in sex.

  As a method for improving these, for example, a laminated sheet in which a polycarbonate resin layer having excellent impact resistance is laminated with a methacrylic resin layer that is hard and has excellent weather resistance has been proposed (for example, Patent Documents 1 and 2).

  Patent Document 1 reports a laminate having excellent scratch resistance while maintaining the impact strength of a polycarbonate resin, and the laminate has 0.1 to 2% by weight of an ultraviolet absorber and a crosslink on one surface of the polycarbonate resin layer. It has an acrylic resin layer (A) made of a methacrylic resin containing less than 30% by weight of an acrylic ester polymer, and 0.1 to 2% by weight of an ultraviolet absorber and a crosslinked acrylic ester polymer 30 to 30% on the other side. It has an acrylic resin layer (B) made of a methacrylic resin containing 70% by weight.

  In Patent Document 2, a transparent resin laminate in which a surface layer portion of an acrylic resin is laminated and integrated on a base portion of a polycarbonate resin by a co-extrusion molding method, has high transparency, and has impact resistance. Those having excellent scratch resistance have been reported.

  However, a laminated sheet obtained by laminating a polycarbonate resin layer and a methacrylic resin layer is deformed in a high temperature environment because the heat resistance of the methacrylic resin layer is poor, or warps due to a change in humidity due to high water absorption. There's a problem.

  In order to solve the problem when laminating the methacrylic resin, a (meth) acrylic ester structural unit and an aliphatic vinyl structural unit are included, and a molar configuration of the (meth) acrylic ester structural unit and the aliphatic vinyl structural unit. It has been proposed to use a vinyl copolymer resin having a ratio of 15:85 to 85:15 instead of a methacrylic resin (Patent Document 3).

  However, according to this method, after copolymerizing a (meth) acrylic ester structural unit and an aromatic vinyl structural unit, this is dissolved in a solvent, and hydrogenated in the presence of a special catalyst, whereby an aromatic is obtained. It is necessary to convert the vinyl structural unit to an aliphatic vinyl structural unit. Therefore, since the manufacturing process is complicated and long, there is a problem that the cost is high.

Japanese Patent No. 3487972 JP 2006-205478 A JP 2009-196125 A

  An object of the present invention is to provide a thermoplastic resin laminate excellent in impact resistance, heat resistance, low water absorption, and scratch resistance, and a transparent resin plate for a display provided with the thermoplastic resin laminate. To do.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above object can be achieved by using a specific heat-resistant styrene resin composition for the surface layer.

  The present invention has been completed based on these findings and has been completed, and provides the following thermoplastic resin laminate and a transparent resin plate for display.

(I) Thermoplastic resin laminate
(I-1) A thermoplastic resin layer (B) and α-methylstyrene and styrene laminated on one side or both sides of the thermoplastic resin layer (B), and 5 α-methylstyrene constituent units Heat-resistant styrene-based resin composition layer (A) containing α-methylstyrene copolymer containing 70% by weight
A thermoplastic resin laminate comprising:
(I-2) The thermoplastic resin laminate according to (I-1), wherein the α-methylstyrene copolymer is obtained by a living polymerization method.
(I-3) The thermoplastic resin laminate according to (I-1) or (I-2), wherein the thermoplastic resin layer (B) contains a polycarbonate resin.
(I-4) At least one selected from the group consisting of hard coat treatment, antireflection treatment, fingerprint prevention treatment and antiglare treatment is applied to at least one surface, (I-1) to (I-3) ) The thermoplastic resin laminate according to any one of the above.
(I-5) (I-1) to (I-4) further comprising an adhesive resin layer (C) between the heat-resistant styrene-based resin composition layer (A) and the thermoplastic resin layer (B). The thermoplastic resin laminate according to any one of the above.
(I-6) The thermoplastic resin laminate according to (I-5), wherein the adhesive resin layer (C) contains a methacrylate / styrene copolymer resin.

(II) Transparent resin plate for display
(II-1) A transparent resin plate for a display comprising the thermoplastic resin laminate according to any one of (I-1) to (I-6).

  The thermoplastic resin laminate of the present invention is excellent in impact resistance, heat resistance, low water absorption, and scratch resistance, and has no problem that the production process is complicated and long. Therefore, the thermoplastic resin laminate of the present invention can be suitably used for a transparent resin plate for display.

  Hereinafter, the present invention will be described in detail.

  The thermoplastic resin laminate of the present invention is composed of a thermoplastic resin layer (B) and α-methylstyrene and styrene laminated on one or both sides of the thermoplastic resin layer (B) and α-methyl. The heat-resistant styrene-based resin composition layer (A) containing an α-methylstyrene copolymer containing 5 to 70% by weight of styrene structural units is provided.

  As one embodiment of the thermoplastic resin laminate of the present invention, at least one selected from the group consisting of hard coat treatment, antireflection treatment, fingerprint prevention treatment and antiglare treatment is applied to at least one surface Is mentioned.

  As another embodiment of the thermoplastic resin laminate of the present invention, an adhesive resin layer (C) is further provided between the heat-resistant styrene resin composition layer (A) and the thermoplastic resin layer (B). The structure which has is mentioned.

  In the thermoplastic resin laminate of the present invention, other layers than the above-mentioned layers can be added within the range where the effects of the present invention are exhibited.

  When the heat-resistant styrenic resin composition layer is A, the thermoplastic resin layer is B, and the adhesive resin layer is C, the layer structure of the thermoplastic resin laminate of the present invention is A / B, A / B / A. A / C / B, A / C / B / C / A, and the like. The above hard coat treatment or the like is applied to at least one outermost surface of this layer structure.

  The thickness of the thermoplastic resin laminate of the present invention is preferably in the range of 0.1 to 10.0 mm. Within this range, defective phenomena are unlikely to occur during sheet processing, and industrially stable production is possible, and there are few occurrences of poor thickness accuracy and poor appearance due to uneven cooling after molding. The thickness is more preferably in the range of 0.3 to 5.0 mm, and still more preferably in the range of 0.5 to 3.0 mm.

  Hereinafter, each layer of the thermoplastic resin laminate of the present invention will be described.

Heat-resistant styrene resin composition layer (A)
The heat-resistant styrene-based resin composition layer (A) of the present invention is composed of an α-methylstyrene copolymer (hereinafter referred to as “component”) composed of α-methylstyrene and styrene and containing 5 to 70% by weight of α-methylstyrene structural units. I)).

  The content of α-methylstyrene constituting Component I in the present invention is 5 to 70% by weight. If it is this range, the effect of the heat resistance improvement in actual use will be acquired, and thermal decomposition will not occur at the time of melt molding processing, and no gas will be generated or yellowing will not occur at the time of molding. The content of α-methylstyrene is preferably 7 to 68% by weight, more preferably 10 to 65% by weight.

  Examples of the other component constituting Component I in the present invention include styrene having good copolymerizability with α-methylstyrene.

  As the other component constituting Component I in the present invention, other copolymerizable monomers can be used together within the range not impairing the object of the present invention other than the above-mentioned monomers. Copolymerizable monomers include conjugated diene monomers such as butadiene and isoprene, methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate, methyl acrylate, ethyl acrylate, and propyl acrylate. And acrylic acid esters such as butyl acrylate. These monomers are useful for improving or adjusting the impact strength, elongation, chemical resistance, etc. of the resin.

  The content of Component I in the heat-resistant styrene resin composition layer (A) of the present invention is preferably 5% by weight or more, more preferably 7% by weight or more, and particularly preferably 10 to 100% by weight.

  The α-methylstyrene copolymer in the present invention can be preferably produced by a living polymerization method. The living polymerization method includes living anion polymerization, living radical polymerization, and living cationic polymerization, and is not particularly limited, and can be produced by any method. Among these, the living anion polymerization method is particularly preferable, but when a monomer containing a polar group is copolymerized, the living radical polymerization method is preferable. A known method can be used as the living anion polymerization method.

  Examples of the method for producing the α-methylstyrene copolymer by the living polymerization method in the present invention include the method described in Japanese Patent No. 4306682.

  The heat-resistant styrene resin composition layer (A) of the present invention can contain a styrene polymer other than Component I. Examples of the monomer constituting the styrenic polymer other than Component I include styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, and the like. The preferred monomer is styrene.

  Various additives may be mixed in the heat-resistant styrene resin composition layer (A) of the present invention. Examples of the additive include an antioxidant, an antistatic agent, an ultraviolet absorber, an anti-coloring agent, a dye, a lubricant, a release agent, and a pigment. The mixing method is not particularly limited, and examples thereof include a method of compounding the entire amount, a method of dry blending the master batch, and a method of dry blending the entire amount.

  The thickness of the heat-resistant styrene resin composition layer (A) of the present invention is preferably in the range of 10 to 500 μm. Within this range, the surface hardness and impact resistance will not be insufficient. The thickness is more preferably in the range of 30-100 μm, and still more preferably in the range of 50-80 μm. The thickness here means the thickness of one layer when there are two heat-resistant styrenic resin composition layers (A).

  The transparency of the heat-resistant styrenic resin composition layer (A) of the present invention is preferably higher, and at least its total light transmittance is preferably 80% or more as measured by ISO13468 method, more preferably 85% or more, More preferably, it is 88% or more.

Thermoplastic resin layer (B)
For the thermoplastic resin layer (B) of the present invention, a resin other than the resin contained in the heat-resistant styrene resin composition layer (A) is used. For example, a polyester resin, a polycarbonate resin, an acrylic resin, Examples thereof include polyolefin resins and polyamide resins. These can be used alone or in combination of two or more. Of these, polycarbonate resin is particularly preferable.

  The content of the polycarbonate resin in the thermoplastic resin layer (B) of the present invention is preferably 70% by weight or more, more preferably 80% by weight or more, and particularly preferably 90 to 100% by weight.

  Various additives may be mixed in the thermoplastic resin layer (B) of the present invention. Examples of the additive include an antioxidant, an antistatic agent, an ultraviolet absorber, an anti-coloring agent, a dye, a lubricant, a release agent, and a pigment. The mixing method is not particularly limited, and examples thereof include a method of compounding the entire amount, a method of dry blending the master batch, and a method of dry blending the entire amount.

  The thickness of the thermoplastic resin layer (B) of the present invention is preferably in the range of 0.05 to 9.0 mm, more preferably 0.1 to 2.0 mm, and still more preferably 0.15 to 1.2 mm.

  The transparency of the thermoplastic resin layer (B) of the present invention is preferably higher, and at least its total light transmittance is preferably 80% or more as measured by the ISO13468 method, more preferably 85% or more, and still more preferably. More than 88%.

Adhesive resin layer (C)
In the present invention, the adhesive resin layer (C) may be sandwiched between the heat-resistant styrenic resin composition layer (A) and the thermoplastic resin layer (B) during coextrusion. The adhesive resin layer (C) of the present invention is effective for improving the adhesion between the heat-resistant styrene resin composition layer (A) and the thermoplastic resin layer (B).

  The resin contained in the adhesive resin layer (C) of the present invention has adhesiveness to both the heat-resistant styrene resin composition layer (A) and the thermoplastic resin layer (B) and is transparent. Is preferred. As the resin having good adhesion to the heat-resistant styrene-based resin composition layer (A), a styrene copolymer resin and a methacrylate / styrene copolymer resin which is a copolymer of styrene and methacrylate are preferable. The ratio of methacrylate constituting the methacrylate / styrene copolymer resin is preferably 10% to 90% by weight. If it is this range, the adhesiveness with respect to both a heat-resistant styrene-type resin composition (A) and a thermoplastic resin (B) will be high. The ratio is more preferably 20% to 80% by weight.

  As the methacrylate / styrene copolymer resin, not only two components of a styrene monomer and a methacrylate monomer but also a monomer copolymerizable therewith, for example, butadiene, acrylonitrile, various acrylates and the like can be copolymerized. Further, for the purpose of improving the impact strength of the methacrylate / styrene copolymer resin, rubber-modified styrene resin, styrene / butadiene copolymer resin, or the like can be mixed.

  Various additives may be mixed in the adhesive resin layer (C) of the present invention. Examples of the additive include an antioxidant, an ultraviolet absorber, a coloring inhibitor, an antistatic agent, a release agent, a lubricant, a dye, and a pigment. The mixing method is not particularly limited, and examples thereof include a method of compounding the entire amount, a method of dry blending the master batch, and a method of dry blending the entire amount.

  The thickness of the adhesive resin layer (C) of the present invention is preferably in the range of 1 to 50 μm, more preferably 2 to 40 μm, still more preferably 2 to 20 μm.

By applying any one or more of hard coat treatment, antireflection treatment, fingerprint prevention treatment, and antiglare treatment to the surface of the thermoplastic resin laminate of the present invention such as hard coat treatment, scratch resistance and glare due to reflection It is possible to prevent fingerprint adhesion, glare caused by reflection, etc. that occur when touched with a finger.

  The method of applying at least one selected from the group consisting of hard coat treatment, antireflection treatment, fingerprint prevention treatment, and antiglare treatment on at least one surface of the thermoplastic resin laminate of the present invention is based on scratch resistance and reflection. Any method may be used as long as it can prevent glare, adhesiveness of fingerprints when touched with a finger, glare due to reflection, and the like.

  As a method for directly performing a hard coat treatment on the surface of the transparent sheet for a touch screen of the present invention, so-called organic compounds such as melamine resin, urethane resin, alkyd resin, fluorine, polyfunctional acrylate, and organosilicone can be used. Any method that coats a system solution and cures it with heat or active energy rays, or a method that coats a so-called organic / inorganic hybrid type solution consisting of a hybrid of silica and polyfunctional acrylate, and cures them with heat or active energy rays. Can be used (hereinafter, a layer formed by a hard coat treatment is also simply referred to as a hard coat).

  As a method of curing the coating, a method of curing with heat or active energy rays can be applied as described above, but in order to shorten the curing time, a method of curing with active energy rays is convenient.

  Examples of the resin that is cured by the active energy ray include, but are not limited to, an active energy ray-curable acrylic resin. The active energy ray-curable acrylic resin is composed of a monomer, an oligomer, a photopolymerization initiator, a photosensitizer, and other components. Examples of monomers used in the acrylic resin include 1,4-butanediol di (meth) acrylate, 1,4-hexanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neodymium Pentyl glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, poly Bifunctional (meth) acrylates such as tetramethylene glycol di (meth) acrylate, 2-hydroxy-3-acryloyloxypropyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, etc. Trifunctional (meth) acrylates and pentaerythritol tetra (meth) acrylate Mention may be made of tetrafunctional or higher functional (meth) acrylates such as acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate and trimethylolpropane tetra (meth) acrylate.

  Examples of the oligomer used for the acrylic resin include polyester acrylates, epoxy acrylates, urethane acrylates, and the like.

  Examples of the polyester portion of polyester acrylates include condensates of dibasic acids and glycols such as phthalic acid and adipic acid, and those obtained by reacting acrylic acid with a polyol obtained by ring-opening polymerization of caprolactone. be able to. Examples of epoxy acrylates include those of various molecular weights such as bisphenol A, bisphenol F, phenol novolac type, and cresol novolac type. Examples of hydroxy acrylates used for urethane acrylates include 2-hydroxyethyl acrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, and pentaerythritol triacrylate. Examples of the isocyanate used for the urethane acrylates include aliphatic and alicyclic diisocyanates, and polyisocyanates having isocyanurate rings that are trimers thereof.

  In the above, “(meth) acrylate” means both acrylate and methacrylate.

  The active energy ray-curable resin is sufficiently cured when irradiated with an electron beam. However, in the case of curing by irradiating with ultraviolet rays, acetophenones, benzophenones, thioxanthones, benzoin, benzoin are used as photopolymerization initiators. Methyl ether, Michler benzoyl benzoate, Michler ketone, diphenyl sulfide, dibenzyl disulfide, diethyl oxide, triphenylbiimidazole, isopropyl-N, N-dimethylaminobenzoate, etc. n-butylamine, triethylylamine as photosensitizers Poly-n-butylphosphine or the like is preferably used alone or as a mixture. The addition amount of the photopolymerization initiator and the photosensitizer is generally about 0.1 to 10 parts by weight with respect to 100 parts by weight of the active energy ray-curable resin.

  The coating composition for forming a hard coat contains various inorganic and organic additives such as silane compounds, solvents, curing catalysts, wettability improvers, plasticizers, antifoaming agents, and thickeners other than those described above. It can be added as necessary. The composition of the hard coat in order to give the surface of the thermoplastic resin laminate of the present invention functions other than preventing surface damage such as imparting antistatic properties, preventing fingerprint adhesion or making adhesion inconspicuous Additives necessary for imparting these functions can be added.

  Before forming a hard coat on the surface of the thermoplastic resin laminate of the present invention, the sheet surface is subjected to corona treatment, ultraviolet irradiation treatment, atmospheric pressure plasma treatment, etc., thereby improving adhesion or applying an appropriate primer. It is effective to form a hard coat after coating.

  If the thickness of the hard coat of the present invention is too thin, it will be difficult to obtain sufficient hardness, and if it is too thick, the elastic modulus of the heat-resistant styrenic resin composition layer (A) and the thermoplastic resin layer (B) and the hard coat A crack or the like is likely to be generated due to a difference in characteristics such as a thermal expansion coefficient. Therefore, it is necessary to select appropriately. The thickness of the organic cross-linked resin or the organic / inorganic hybrid type hard coat is preferably 1 to 30 μm, particularly 2 to 8 μm. If it is the thickness of this range, sufficient hardness will be obtained and it will become difficult to generate | occur | produce a crack. Here, when there are two hard coat layers, the thickness of the hard coat means the thickness of one layer.

  As a method for producing the thermoplastic resin laminate of the present invention, a method by coextrusion, a method of laminating by hot press, a method of laminating through an adhesive, and the like can be used. The method by coextrusion is not specifically limited, A well-known method can be used. For example, in the feed block method, the heat-resistant styrene resin composition layer (A) is laminated on one or both of the thermoplastic resin layers (B) in the feed block, extruded into a sheet shape with a T-die, and then passed through a forming roll. While cooling, the desired thermoplastic resin laminate is formed. In the multi-manifold system, the heat-resistant styrene-based resin composition layer (A) is laminated on one or both of the thermoplastic resin layers (B) in the multi-manifold die, extruded into a sheet shape, and then passed through a molding roll. Cool to form the desired thermoplastic resin laminate.

  Moreover, the method to bond together through an adhesive agent is not specifically limited, either, A well-known method can be used. For example, an adhesive is applied to the thermoplastic resin layer (B) using a spray, a gravure roll, a brush, etc., and the heat-resistant styrenic resin composition layer (A) is layered thereon and pressure-bonded until the adhesive is cured, A desired laminate is formed.

  The thermoplastic resin laminate of the present invention is characterized by being excellent in impact resistance, heat resistance, low water absorption, and scratch resistance. Therefore, the thermoplastic resin laminate of the present invention can be suitably used as an optical material such as a transparent substrate material and a transparent protective material, and can be particularly suitably used for a transparent resin plate for display.

  The display in the present invention means a so-called flat panel display, and examples thereof include various liquid crystal displays such as TN system, VA system, and IPS system, and organic electroluminescence (organic EL) panels.

  Examples are given below to illustrate the present invention in more detail. However, the present invention is not limited to these examples.

  The thermoplastic resin laminates obtained in the examples and comparative examples were evaluated by the tests shown below.

<Abrasion resistance test (pencil hardness)>
Based on JIS K5400, scratching was performed with a pencil lead pressurized with a load of 750 g. When scratches are not recognized more than twice in 5 tests, replace the pencil with the higher density symbol and perform the same test, find a pencil with more than 2 scratches on the paint film, A density symbol one level lower than the pencil density symbol was recorded. Those having a pencil hardness of 2H or more were considered good.

<Impact resistance (ball drop test)>
A 66.87 g spherical weight was dropped freely from a height of 20 cm, and the presence or absence of cracks reaching the back of the specimen was evaluated. A test piece that did not cause cracks reaching the back surface of the test piece was considered good.

<Heat resistance, low hygroscopicity (constant temperature and humidity test)>
The test piece was cut into 10 cm × 5 cm, placed in a constant temperature and humidity test apparatus set at a temperature of 85 ° C. and a relative humidity of 85%, and placed on a flat ground glass sheet and held in that state for 72 hours. The test piece is taken out, placed on a flat glass sheet, the gap between the four corners of the test piece and the glass surface is measured, and the average value of the four measured values is warped. Good warpage is 0.3 mm or less.

Example 1
Extruder screw diameter: 40 mm, L / D = 25 single screw extruder (a) and extruder screw diameter: 20 mm, L / D = 20 single screw extruder (b) are multi-manifold type multi-layer die Connected to. Styrene-α-methylstyrene copolymer resin (Vicat softening point: 132 ° C, 230 ° C, melt flow rate measured at 10 kg load; 4.2, ratio of styrene to α-methylstyrene (weight ratio) ); 48/52, abbreviated as SαS), and MMA (methyl methacrylate) -styrene copolymer resin (manufacturer: Denki Kagaku Kogyo Co., Ltd., varieties: Denka TX-100S, MS) in the extruder (b). Then, a 0.07 mm transparent thermoplastic resin laminated film in which a 0.06 mm thick styrene-α-methylstyrene copolymer resin layer and a 0.01 mm thick MMA-styrene copolymer resin layer were laminated was produced. This film and a 0.8 mm polycarbonate sheet (manufacturer: Teijin Chemicals Ltd., varieties: Panlite sheet, abbreviated as PC-a) are laminated by press molding, and a styrene-α-methylstyrene copolymer resin layer 0.06 mm from the surface. A three-layer thermoplastic resin laminate having a thickness of 0.87 mm comprising a MMA-styrene copolymer resin layer of 0.01 mm and a polycarbonate resin layer of 0.8 mm was obtained.

  UV curable hard coat paint made of polyfunctional acrylic resin (Nippon Synthetic Chemical Industry Co., Ltd. UV-1700B 100 g), silica (Nissan Chemical Co., Ltd.silica sol IPA-ST 150 g), initiator (BASF's Irgacure 184 4 g) and a solvent (PGM 150 g) were dissolved and mixed to prepare a crosslinked resin coating. This cross-linked resin coating is applied to both sides of the thermoplastic resin laminate obtained by the flow coat method, cured by ultraviolet rays to form a cross-linked resin layer of approximately 4 μm, and a hard-coated transparent thermoplastic resin laminate is obtained. Obtained.

Comparative Example 1
Extruder screw diameter: 40 mm, L / D = 25 single screw extruder (a) and extruder screw diameter: 20 mm, L / D = 242 single screw extruder (b) are multi-manifold type multi-layer die Connected to. Polycarbonate resin (manufacturer: Sumitomo Dow Co., Ltd., varieties: Caliber 301-10, abbreviated as PC-b) is used for the extruder (a), and methacrylic resin (manufacturer: Mitsubishi Rayon Co., Ltd., varieties) is used for the extruder (b). : Acrypet V (hereinafter abbreviated as PMMA-a), and a transparent thermoplastic resin laminate with a methacrylic resin layer thickness of 0.06 mm, a polycarbonate resin layer of 0.8 mm, and an overall thickness of 0.86 mm was prepared from the surface. .

  UV curable hard coat paint made of polyfunctional acrylic resin (Nippon Synthetic Chemical Industry Co., Ltd. UV-1700B 100 g), silica (Nissan Chemical Co., Ltd.silica sol IPA-ST 150 g), initiator (BASF's Irgacure 184 4 g) and a solvent (PGM 150 g) were dissolved and mixed to prepare a crosslinked resin coating. This cross-linked resin coating is applied to both sides of the thermoplastic resin laminate obtained by the flow coat method, cured by ultraviolet rays to form a cross-linked resin layer of approximately 4 μm, and a hard-coated transparent thermoplastic resin laminate is obtained. Obtained.

Comparative Example 2
UV curable hard coat paint made of polyfunctional acrylic resin (Nippon Synthetic Chemical Industry Co., Ltd. UV-1700B 100 g), silica (Nissan Chemical Co., Ltd.silica sol IPA-ST 150 g), initiator (BASF's Irgacure 184 4 g) and a solvent (PGM 150 g) were dissolved and mixed to prepare a crosslinked resin coating. This cross-linked resin coating is applied to both sides of a 1.0 mm thick transparent methacrylic resin plate (made by Asahi Kasei Chemical, Delaglass, abbreviated as PMMA-b) by the flow coating method, and cured with ultraviolet rays to form a cross-linked resin layer of approximately 4 μm. Thus, a transparent methacrylic resin plate treated with a hard coat was obtained.

Comparative Example 3
UV curable hard coat paint made of polyfunctional acrylic resin (Nippon Synthetic Chemical Industry Co., Ltd. UV-1700B 100 g), silica (Nissan Chemical Co., Ltd.silica sol IPA-ST 150 g), initiator (BASF's Irgacure 184 4 g) and a solvent (PGM 150 g) were dissolved and mixed to prepare a crosslinked resin coating. This cross-linked resin coating is applied to both sides of a transparent polycarbonate plate (manufacturer: Teijin Chemicals, variety: Panlite sheet) with a thickness of 0.8 mm by the flow coat method, and cured with ultraviolet rays to form a cross-linked resin layer of approximately 4 μm. A transparent polycarbonate plate treated with a hard coat was obtained.

  The synthetic resin sheets obtained in Example 1 and Comparative Examples 1 to 3 were subjected to pencil hardness, falling ball test, and constant temperature and humidity test, and the obtained results are shown in Table 1.

  Example 1 showed good results in all tests. However, Comparative Example 1 is a constant temperature and humidity test (warp generation), Comparative Example 2 is a falling ball test (crack generation), and Comparative Example 3 is poor in pencil hardness (H or less). It was not obtained.

Claims (7)

The thermoplastic resin layer (B), and composed of α-methylstyrene and styrene laminated on one side or both sides of the thermoplastic resin layer (B) and containing 5-70% by weight of α-methylstyrene structural unit Heat-resistant styrene-based resin composition layer containing an α-methylstyrene copolymer (A)
A thermoplastic resin laminate comprising:   The thermoplastic resin laminate according to claim 1, wherein the α-methylstyrene copolymer is obtained by a living polymerization method.   The thermoplastic resin laminate according to claim 1 or 2, wherein the thermoplastic resin layer (B) contains a polycarbonate resin.   The thermoplastic resin laminate according to any one of claims 1 to 3, wherein at least one selected from the group consisting of hard coat treatment, antireflection treatment, fingerprint prevention treatment and antiglare treatment is applied to at least one surface. body.   The thermoplastic resin laminate according to any one of claims 1 to 4, further comprising an adhesive resin layer (C) between the heat-resistant styrene-based resin composition layer (A) and the thermoplastic resin layer (B). .   The thermoplastic resin laminate according to claim 5, wherein the adhesive resin layer (C) contains a methacrylate / styrene copolymer resin.   A transparent resin plate for a display, comprising the thermoplastic resin laminate according to claim 1.