JP2013144365A - Method of manufacturing laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a laminate comprising a thermoplastic resin layer and a polyolefin layer laminated thereon.SOLUTION: A method of manufacturing a laminate includes: a step of melt-coextruding a thermoplastic resin and polyolefin to obtain a film-like material; and a step of inserting the film-like material between a shaping roll and a touch roll to manufacture the laminate in which a thermoplastic resin layer and a polyolefin layer are laminated. In the laminate, a surface in contact with the polyolefin resin layer of the thermoplastic resin layer is a matt surface. The method uses the shaping roll, in which the maximum height roughness (Rz) on the outer peripheral surface and the average length (RSm) of contour curve elements satisfy the relation of 0.2≤Rz/RSm≤1.0.

Description

  The present invention relates to a method for producing a laminate in which a thermoplastic resin layer and a polyolefin layer are laminated.

  A mat film having a mat shape (uneven shape) on the film surface has a high surface haze on the surface (mat surface), and is often used in a liquid crystal display device as a light diffusion film. Patent Document 1 describes that a mat film made of polycarbonate resin is used as a light diffusion film. The matte film is usually formed by embossing roll transfer to form a predetermined matte shape, or cross-linked resin particles or inorganic fine particles are mixed into the resin constituting the film substrate, and then by single layer melt extrusion molding or multilayer melt extrusion molding. A mat shape is formed on the surface of the film when the particles come out, and a mat shape is formed by coating the surface of the base film with a UV curable resin or thermosetting resin in which spherical beads are dispersed. And the like that form

  The mat film may be used by being bonded to a polarization separation sheet that is disposed between a backlight unit of a liquid crystal display device and a liquid crystal panel and used for improving luminance. This polarization separation sheet is generally about 100 μm thick even when it is thick, so that when the area becomes large, the rigidity of the sheet itself is not sufficient and the self-supporting property becomes insufficient. In order to suppress these, the sheet itself may bend or wavy due to the influence of heat, etc., or a rainbow pattern may be generated due to interference when it comes into contact with the liquid crystal panel. A matte film made of a thermoplastic resin, particularly a polycarbonate resin, is bonded to both surfaces of the polarization separation sheet as a polarization separation sheet protective film.

  The mat film may be damaged or dust may adhere to the mat surface of the mat film at the time of bonding with the polarization separation sheet or at the time of transport. Therefore, usually, a protective film made of a peelable polyolefin is bonded to the mat surface, and then the surface of the mat film that is not bonded to the protective film is bonded to a polarized light separating sheet, The protective film is peeled from the surface. In many cases, the protective film is peeled off at the final stage of assembly of the liquid crystal display device, and accordingly, it is necessary to have appropriate adhesiveness and peelability to the matte film. Bonding the protective film to the matte film is a protective film with a pressure-sensitive adhesive or adhesive coated on one side in consideration of adhesiveness or peelability, or a protective film with a pressure-sensitive adhesive layer containing a pressure-sensitive adhesive. Usually used.

JP 2004-53998 A

  When a protective film made of polyolefin is bonded to the mat surface of a mat film made of thermoplastic resin, the protective film may be wrinkled at the time of bonding, which may result in a defective product. Furthermore, when the protective film is peeled off, a part of the pressure-sensitive adhesive or adhesive may remain on the mat film, which may be an optical defect. Moreover, since a bonding step is required, the number of steps increases, which is complicated and disadvantageous in terms of cost.

Accordingly, an object of the present invention is to provide a peelable polyolefin layer laminated on the mat surface of the thermoplastic resin layer having the mat surface without passing through the bonding step, and surface haze on the mat surface. It is providing the manufacturing method of a laminated body with high.

  As a result of intensive studies to solve the above problems, the present inventors have completed the present invention.

That is, the present invention relates to the following inventions.
(1) A thermoplastic resin and a polyolefin are melt-coextruded to obtain a film-like product, the film-like product is inserted between a shaping roll and a touch roll, and the thermoplastic resin layer and the polyolefin layer are laminated. In the laminate, the surface of the thermoplastic resin layer in contact with the polyolefin resin layer is a mat surface, and as the shaping roll, the maximum height of the contour curve on the outer peripheral surface The manufacturing method of the laminated body characterized by using the shaping roll with which (Rz) and the average length (RSm) of an outline curve element satisfy | fill the relationship of 0.2 <= Rz / RSm <= 1.0.
(2) The manufacturing method as described in said (1) which inserts a film-like material between a shaping roll and a touch roll so that the surface of a thermoplastic resin layer may contact a shaping roll.
(3) The production method according to (1) or (2), wherein the thermoplastic resin layer and the polyolefin layer are peelable.
(4) The thermoplastic resin is at least one selected from the group consisting of polycarbonate resins, acrylic resins, polyester resins, styrene resins, methyl methacrylate-styrene resins, ABS resins, and AS resins. The manufacturing method in any one of said (1)-(3).
(5) The production according to any one of (1) to (4), wherein the polyolefin is at least one selected from the group consisting of a polyethylene resin, a polypropylene resin, and a modified polyolefin resin that is a modified product thereof. Method.
(6) The manufacturing method according to any one of (1) to (5), wherein both surfaces of the thermoplastic resin layer are mat surfaces.

  According to the present invention, since the peelable polyolefin layer is laminated on the mat surface of the thermoplastic resin layer having the mat surface without being bonded, no bonding step is required, and from the thermoplastic resin layer Even when the polyolefin layer is peeled off, no adhesive or pressure-sensitive adhesive remains on the thermoplastic resin layer, and a laminate having a high surface haze on the mat surface can be obtained.

It is a schematic explanatory drawing which shows one Embodiment of the manufacturing method of the laminated body of this invention.

Hereinafter, the present invention will be described in detail.
The method for producing a laminated board of the present invention (hereinafter sometimes referred to as the production method of the present invention) is obtained by melt coextrusion of a thermoplastic resin and a polyolefin to obtain a film-like product, and the film-like product is used as a shaping roll. A laminated board is obtained by inserting between touch rolls.

  In the production method of the present invention, first, the thermoplastic resin and the polyolefin are put into separate extruders and melt-kneaded. Hereinafter, a thermoplastic resin and polyolefin are demonstrated in order.

[Thermoplastic resin]
The thermoplastic resin is made of a resin other than polyolefin, which will be described later, and is a polycarbonate resin, acrylic resin, polyester resin, polystyrene resin, methyl methacrylate-styrene resin, ABS (acrylonitrile-butadiene-styrene copolymer) system. It is preferably at least one selected from the group consisting of a resin and an AS (acrylonitrile-styrene copolymer) resin, and the resin is preferably a resin having good transparency. Among them, it is preferable to use a polycarbonate-based resin from the viewpoints of high transparency, excellent impact resistance, heat resistance, dimensional stability, flame retardancy, and few optical foreign matters. Two or more of the above resins may be mixed and used as long as the thermoplastic resin does not impair the transparency.

<Polycarbonate resin>
As the polycarbonate resin, for example, it is preferable to use an aromatic polycarbonate resin excellent in heat resistance, mechanical strength, transparency, and the like.
As an aromatic polycarbonate resin, for example, a resin obtained by reacting a dihydric phenol and a carbonate precursor by an interfacial polycondensation method or a melt transesterification method, a carbonate prepolymer was polymerized by a solid phase transesterification method. Examples thereof include a resin and a resin obtained by polymerizing by a ring-opening polymerization method of a cyclic carbonate compound.

  Examples of the dihydric phenol include hydroquinone, resorcinol, 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis {(4-hydroxy-3,5-dimethyl) phenyl} methane, 1,1- Bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane (commonly called bisphenol A), 2,2-bis { (4-hydroxy-3-methyl) phenyl} propane, 2,2-bis {(4-hydroxy-3,5-dimethyl) phenyl} propane, 2,2-bis {(4-hydroxy-3,5-dibromo) ) Phenyl} propane, 2,2-bis {(3-isopropyl-4-hydroxy) phenyl} propane, 2,2-bis {(4 Hydroxy-3-phenyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3-methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,4-bis (4-hydroxyphenyl) -2-methylbutane, 2,2-bis (4-hydroxyphenyl) pentane, 2,2-bis (4-hydroxyphenyl) -4 -Methylpentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3 5-trimethylcyclohexane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis {(4-hydroxy 3-methyl) phenyl} fluorene, α, α′-bis (4-hydroxyphenyl) -o-diisopropylbenzene, α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene, α, α′-bis (4-hydroxyphenyl) -p-diisopropylbenzene, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantane, 4,4′-dihydroxydiphenylsulfone, 4,4′-dihydroxydiphenylsulfoxide, 4 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ester, etc., and these may be used alone or in combination of two or more. can do.

  Among them, bisphenol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) -3 -Methylbutane, 2,2-bis (4-hydroxyphenyl) -3,3-dimethylbutane, 2,2-bis (4-hydroxyphenyl) -4-methylpentane, 1,1-bis (4-hydroxyphenyl) It is preferable to use a dihydric phenol selected from the group consisting of −3,3,5-trimethylcyclohexane and α, α′-bis (4-hydroxyphenyl) -m-diisopropylbenzene alone or in combination, Use of bisphenol A alone, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, At least one selected from the group consisting of enol A, 2,2-bis {(4-hydroxy-3-methyl) phenyl} propane, and α, α'-bis (4-hydroxyphenyl) -m-diisopropylbenzene. The combined use with a monohydric phenol is preferred.

  As the carbonate precursor, for example, carbonyl halide, carbonate ester, haloformate or the like is used, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like.

<Acrylic resin>
For example, methacrylic resin is used as the acrylic resin. The methacrylic resin is a polymer mainly composed of a methacrylic acid ester, and may be a homopolymer of the methacrylic acid ester. A copolymer may also be used. Here, as the methacrylic acid ester, an alkyl ester of methacrylic acid is usually used.

  The preferred monomer composition of the methacrylic resin is 50 to 100% by weight of alkyl methacrylate, 0 to 50% by weight of alkyl acrylate, and 0 to 49% by weight of other monomers based on all monomers. More preferably, the alkyl methacrylate is 50 to 99.9% by weight, the alkyl acrylate is 0.1 to 50% by weight, and other monomers are 0 to 49% by weight.

  Here, examples of the alkyl methacrylate include methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, and the like. The alkyl group usually has 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms. It is. Of these, methyl methacrylate is preferably used.

  Examples of the alkyl acrylate include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and the like. The alkyl group usually has 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms. is there.

The monomer other than alkyl methacrylate and alkyl acrylate may be, for example, a monofunctional monomer, that is, a compound having one polymerizable carbon-carbon double bond in the molecule, Although it may be a polyfunctional monomer, that is, a compound having at least two polymerizable carbon-carbon double bonds in the molecule, a monofunctional monomer is preferably used.
Examples of the monofunctional monomer include styrene monomers such as styrene, α-methylstyrene, and vinyl toluene, alkenyl cyanide such as acrylonitrile and methacrylonitrile, acrylic acid, methacrylic acid, maleic anhydride, N -Substituted maleimide and the like.
Examples of polyfunctional monomers include polyunsaturated carboxylic acid esters of polyhydric alcohols such as ethylene glycol dimethacrylate, butanediol dimethacrylate, trimethylolpropane triacrylate, allyl acrylate, allyl methacrylate, and cinnamon. Alkenyl esters of unsaturated carboxylic acids such as allyl acid, polyalkenyl esters of polybasic acids such as diallyl phthalate, diallyl maleate, triallyl cyanurate, triallyl isocyanurate, aromatic polyalkenyl compounds such as divinylbenzene, etc. Can be mentioned.

  In addition, as for said alkyl methacrylate, alkyl acrylate, and monomers other than these, respectively, you may use those 2 or more types as needed.

  From the viewpoint of heat resistance, the methacrylic resin preferably has a glass transition temperature of 70 ° C. or higher, more preferably 80 ° C. or higher, and further preferably 90 ° C. or higher. This glass transition temperature can be appropriately set by adjusting the type of monomer and the ratio thereof.

  The methacrylic resin can be prepared by polymerizing the monomer component by a method such as suspension polymerization, emulsion polymerization, or bulk polymerization. At that time, it is preferable to use an appropriate chain transfer agent at the time of polymerization in order to obtain a suitable glass transition temperature or to obtain a melt viscosity exhibiting a moldability to a suitable laminate. What is necessary is just to determine the addition amount of a chain transfer agent suitably according to the kind of monomer, its ratio, etc.

<Rubber particles>
Rubber particles can also be blended with the acrylic resin. Here, as the rubber particles, for example, acrylic rubber particles, butadiene rubber particles, styrene-butadiene rubber particles and the like can be used, and among them, acrylic rubber particles from the viewpoint of weather resistance and durability. Is preferably used.

The acrylic rubber particle is a particle containing an elastic polymer mainly composed of an acrylate ester as a rubber component, and may be a particle having a single layer structure made of only this elastic polymer, or a layer of this elastic polymer. For example, it may be a multi-layered particle having a polymer layer mainly composed of a methacrylic acid ester, but it may be a multi-layered particle in terms of the surface hardness of a mat film made of an acrylic resin. preferable.
The elastic polymer may be a homopolymer of an acrylate ester or a copolymer of 50% by weight or more of an acrylate ester and 50% by weight or less of other monomers. . Here, as the acrylic ester, an alkyl ester of acrylic acid is usually used.

  A preferable monomer composition of the elastic polymer mainly composed of an acrylate ester is 50 to 99.9% by weight of alkyl acrylate, 0 to 49.9% by weight of alkyl methacrylate, based on all monomers, The monofunctional monomer other than these is 0 to 49.9% by weight, and the polyfunctional monomer is 0.1 to 10% by weight.

Here, the alkyl acrylate in the elastic polymer is, for example, the same as the examples of the alkyl acrylate previously mentioned as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms. Preferably it is 4-8.
The alkyl methacrylate in the elastic polymer is, for example, the same as the examples of alkyl methacrylates previously mentioned as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms, preferably Is 1-4.

  Examples of the monofunctional monomer other than alkyl acrylate and alkyl methacrylate in the elastic polymer include, for example, monofunctional monomers other than alkyl methacrylate and alkyl acrylate mentioned above as the monomer component of methacrylic resin. This is the same as the example. Of these, styrene monomers such as styrene, α-methylstyrene and vinyltoluene are preferably used.

  The polyfunctional monomer in the elastic polymer is, for example, the same as the examples of the polyfunctional monomer previously mentioned as the monomer component of the methacrylic resin, among them, an alkenyl ester of an unsaturated carboxylic acid, Polyalkenyl esters of polybasic acids are preferably used.

  The alkyl acrylate, the alkyl methacrylate, the monofunctional monomer other than these, and the polyfunctional monomer in the elastic polymer may each be used in combination of two or more as necessary.

When the acrylic rubber particles having a multilayer structure are used, as a suitable example, a polymer layer mainly composed of methacrylic acid ester is provided outside the above-mentioned elastic polymer layer mainly composed of acrylate ester. That is, the above-mentioned elastic polymer mainly composed of an acrylate ester is used as an inner layer, and the polymer mainly composed of a methacrylic ester is used as an outer layer. Here, as the methacrylic acid ester which is a monomer component of the polymer in the outer layer, alkyl methacrylate is usually used.
The outer layer polymer is usually formed at a ratio of 10 to 400 parts by weight, preferably 20 to 200 parts by weight with respect to 100 parts by weight of the inner layer elastic polymer. By setting the polymer of the outer layer to 10 parts by weight or more with respect to 100 parts by weight of the elastic polymer of the inner layer, the elastic polymer is less likely to aggregate and the transparency of the acrylic resin layer is improved.

  The preferred monomer composition of the polymer of the outer layer is based on all monomers, the alkyl methacrylate is 50 to 100% by weight, the alkyl acrylate is 0 to 50% by weight, and other monomers are 0 to 0% by weight. 50% by weight, and 0 to 10% by weight of the polyfunctional monomer.

  The alkyl methacrylate in the polymer of the outer layer is, for example, the same as the examples of alkyl methacrylate previously mentioned as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms, preferably 1-4. Of these, methyl methacrylate is preferably used.

  The alkyl acrylate in the polymer of the outer layer is, for example, the same as the examples of the alkyl acrylate mentioned above as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms, preferably 1-4.

  Examples of monomers other than alkyl methacrylate and alkyl acrylate in the polymer of the outer layer include, for example, monofunctional monomers other than alkyl methacrylate and alkyl acrylate mentioned above as the monomer component of methacrylic resin. It is the same as that of an example, and as a polyfunctional monomer, it is the same as that of the example of the polyfunctional monomer previously mentioned as a monomer component of a methacryl resin, for example.

  In addition, as for the alkyl methacrylate, the alkyl acrylate, the monomer other than these, and the polyfunctional monomer in the polymer of the outer layer, two or more kinds thereof may be used as necessary.

  Further, as a suitable example of the acrylic rubber particles having a multilayer structure, a polymer mainly composed of a methacrylic acid ester is further provided inside the elastic polymer layer mainly composed of the above-mentioned acrylic ester which is the inner layer of the above two-layer structure. In other words, the polymer mainly composed of the methacrylic acid ester is used as the inner layer, the above-mentioned elastic polymer mainly composed of the acrylate ester is used as the intermediate layer, and the polymer mainly composed of the above methacrylic acid ester. It is also possible to include those having at least a three-layer structure, with the outer layer as the outer layer. Here, as a methacrylic acid ester which is a monomer component of the polymer of the inner layer, alkyl methacrylate is usually used. The polymer of the inner layer is usually formed at a ratio of 10 to 400 parts by weight, preferably 20 to 200 parts by weight, with respect to 100 parts by weight of the elastic polymer of the intermediate layer.

  A preferable monomer composition of the polymer of the inner layer is 70 to 100% by weight of alkyl methacrylate, 0 to 30% by weight of alkyl acrylate, and 0 to 30% of other monomers based on all monomers. 30% by weight, and 0 to 10% by weight of the polyfunctional monomer.

The alkyl methacrylate in the polymer of the inner layer is, for example, the same as the examples of alkyl methacrylate previously mentioned as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms, preferably 1-4. Of these, methyl methacrylate is preferably used.
In addition, the alkyl acrylate in the polymer of the inner layer is, for example, the same as the examples of the alkyl acrylate previously mentioned as the monomer component of the methacrylic resin, and the alkyl group usually has 1 to 8 carbon atoms. Preferably it is 1-4.

  Examples of monomers other than alkyl methacrylate and alkyl acrylate in the polymer of the inner layer include, for example, monofunctional monomers other than alkyl methacrylate and alkyl acrylate mentioned above as the monomer component of methacrylic resin. The examples are the same as the examples, and examples of the polyfunctional monomer are the same as the examples of the polyfunctional monomer described above as the monomer component of the methacrylic resin.

  In addition, as for the alkyl methacrylate, the alkyl acrylate, the monomer other than these, and the polyfunctional monomer in the polymer of the inner layer, two or more kinds thereof may be used as necessary.

Acrylic rubber particles can be prepared by polymerizing the monomer component of the above-mentioned elastic polymer mainly composed of an acrylate ester by at least one stage reaction by an emulsion polymerization method or the like. At this time, as described above, when a polymer layer mainly composed of methacrylic acid ester is formed outside the elastic polymer layer, the monomer component of the outer layer polymer is added to the elastic polymer layer. What is necessary is just to graft to the said elastic polymer by making it superpose | polymerize by reaction of at least 1 step | paragraph by emulsion polymerization method etc. in presence of a polymer.
Further, as described above, when a polymer layer mainly composed of methacrylic acid ester is formed inside the elastic polymer layer, first, the monomer component of the polymer in the inner layer is Polymerization is performed by at least one stage reaction by an emulsion polymerization method or the like, and then the monomer component of the elastic polymer is polymerized by at least one stage reaction by an emulsion polymerization method or the like in the presence of the resulting polymer. In the presence of the resulting elastic polymer, the monomer component of the outer layer polymer is polymerized in an at least one-stage reaction by an emulsion polymerization method or the like. To be grafted to the elastic polymer. When the polymerization of each layer is performed in two or more stages, it is sufficient that the monomer composition as a whole is within a predetermined range, not the monomer composition of each stage.

  Regarding the particle diameter of the acrylic rubber particles, the average particle diameter of the elastic polymer layer mainly composed of acrylic acid ester in the rubber particles is preferably 0.01 to 0.4 μm, and more preferably 0. It is 05-0.3 micrometer, More preferably, it is 0.07-0.25 micrometer. If the average particle size of the elastic polymer layer is larger than 0.4 μm, the transparency of the matte film made of acrylic resin is lowered and the transmittance is lowered. Further, if the average particle size of the elastic polymer layer is smaller than 0.01 μm, it is not preferable because the surface hardness of the thermoplastic resin layer is lowered and easily damaged.

The average particle diameter was determined by mixing acrylic rubber particles with a methacrylic resin to form a film, dyeing the elastic polymer layer with ruthenium oxide in the cross section, and observing with an electron microscope. It can be determined from the diameter.
That is, when acrylic rubber particles are mixed with methacrylic resin and the cross section thereof is dyed with ruthenium oxide, the methacrylic resin of the parent phase is not dyed, and the polymer mainly composed of methacrylic acid ester is outside the elastic polymer layer. If there is a layer, the polymer of this outer layer is not dyed, only the elastic polymer layer is dyed. The diameter can be determined. When a polymer layer mainly composed of methacrylic acid ester is present inside the elastic polymer layer, the polymer of the inner layer is not dyed and the outer elastic polymer layer is dyed 2 In this case, the outer diameter of the two-layer structure, that is, the outer diameter of the elastic polymer layer may be considered.

  The content ratio of the rubber particles with respect to the acrylic resin is 40% by weight or less, preferably 30% by weight or less of the entire acrylic resin. When the content ratio of the rubber particles is larger than 40% by weight of the entire acrylic resin, the surface hardness of the thermoplastic resin layer is lowered and the surface is easily damaged.

<Polyester resin>
Examples of the polyester-based resin include polyethylene terephthalate and polyethylene naphthalate, and examples thereof include crystalline polyester and amorphous polyester. From the viewpoint of transparency, an amorphous resin is preferable.
The polyester resin can be composed of a polyester resin composition composed of a crystalline polyester and an amorphous polyester. The polyester resin is produced by polycondensation of a dibasic acid and a polyhydric alcohol.
Examples of the dibasic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid, and aliphatic dicarboxylic acids such as adipic acid.
Examples of the polyhydric alcohol include ethylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol, pentaethylene glycol, 2,2-dimethyltrimethylene glycol, hexamethylene glycol, neopentyl glycol. Diols such as
Said dibasic acid and polyhydric alcohol are used by arbitrary combinations. Specifically, terephthalic acid / ethylene glycol copolymer, terephthalic acid / ethylene glycol / 1,4-cyclohexane dimethanol terpolymer, 2,6-naphthalenedicarboxylic acid / ethylene glycol copolymer, terephthalate Examples include acid / 1,4-butanediol copolymer.
Examples of the crystalline polyester include a resin marketed under the trade name “Byron” (manufactured by Toyobo Co., Ltd.).
Examples of the amorphous polyester include amorphous polyethylene terephthalate (so-called APET) and terephthalic acid / ethylene glycol / 1,4-cyclohexanedimethanol terpolymer (example: trade name “PETG” (yeast Man Chemical Co., Ltd.)).

<Polystyrene resin>
The polystyrene-based resin is a polymer containing 50% by mass or more, preferably 70% by mass or more of styrene units as a structural unit, and a part thereof can be copolymerized with styrene as long as it contains 50% by mass or more of styrene units. Such a copolymer may be substituted with a monofunctional unsaturated monomer unit.

Examples of the copolymerizable monofunctional unsaturated monomer include ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl methacrylate, and the like. Methacrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, etc .; methacryl Examples thereof include unsaturated acids such as acid and acrylic acid; α-methylstyrene, methacrylonitrile, maleic anhydride, phenylmaleimide, cyclohexylmaleimide and the like. Moreover, this copolymer may further contain a glutaric anhydride unit and a glutarimide unit.
Further, a blend of a diene rubber, an acrylic rubber or the like as a rubbery polymer may be contained in the polymer or copolymer described above.

<Methyl methacrylate-styrene resin>
Examples of the methyl methacrylate-styrene resin include, for example, a styrene unit content of 20% by mass to 95% by mass and a methyl methacrylate unit content of 80% by mass to 5% by mass, preferably a styrene unit content of 70% by mass or more. And a copolymer having a methyl methacrylate unit content of 30% by mass or less.

<AS resin>
Examples of the AS (acrylonitrile-styrene) resin include a copolymer in which a monomer unit derived from acrylonitrile and a monomer unit derived from styrene are randomly copolymerized. The content of monomer units derived from acrylonitrile is usually 2 to 50% by weight (that is, the content of monomer units derived from styrene is usually 98 to 50% by weight), preferably 20 to 30% by weight. (That is, the content of monomer units derived from styrene is preferably 80 to 70% by weight). However, the total of the monomer units contained in the AS resin is 100% by weight.

<ABS resin>
Examples of the ABS (acrylonitrile-butadiene-styrene) resin include a copolymer obtained by graft polymerization of the olefin rubber (for example, polybutadiene rubber) to about 40% by weight or less on the AS resin described above.
In addition, in order to obtain good transparency, from the viewpoint of bringing the refractive index value of the resin component closer to the refractive index value of the rubber component, a copolymer of styrene, methyl methacrylate and other copolymerizable monomers as the resin component. A so-called transparent ABS which is a polymer is preferred.
Examples of the copolymerizable monomer include acrylonitrile. Moreover, about transparent ABS, what was disclosed by Unexamined-Japanese-Patent No. 2006-265406 is mentioned, for example.

[Polyolefin]
The polyolefin is preferably at least one selected from the group consisting of polyethylene resins, polypropylene resins and modified polyolefin resins which are modified products thereof. When the laminate of the present invention is used in a liquid crystal display device, since the polyolefin functions as a protective film and is finally peeled off, it is preferable to use a polyethylene resin or a polypropylene resin that can be obtained at a relatively low cost. . Two or more of the above resins may be mixed and used as the polyolefin.

<Polyethylene resin>
Examples of the polyethylene resin include an ethylene homopolymer, an ethylene-propylene random copolymer, and an ethylene-α-olefin copolymer.
Examples of the α-olefin used in the ethylene-α-olefin copolymer include 1-butene, 2-methyl-1-propene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2 -Ethyl-1-butene, 2,3-dimethyl-1-butene, 1-pentene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl -1-butene, 1-heptene, methyl-1-hexene, dimethyl-1-pentene, ethyl-1-pentene, trimethyl-1-butene, methylethyl-1-butene, 1-octene, methyl-1-pentene, Ethyl-1-hexene, dimethyl-1-hexene, propyl-1-heptene, methylethyl-1-heptene, trimethyl-1-pentene, propyl-1-pentene, diethyl Examples include -1-butene, 1-nonene, 1-decene, 1-undecene, and 1-dodecene. Of these, 1-butene, 1-pentene, 1-hexene, and 1-octene are preferably used.

<Polypropylene resin>
Examples of the polypropylene resin include propylene homopolymer, propylene-ethylene random copolymer, propylene-α-olefin random copolymer, propylene-ethylene-α-olefin copolymer, propylene homopolymer component or mainly. Examples thereof include a polypropylene-based copolymer composed of a copolymer component composed of propylene and a copolymer component of propylene and ethylene and / or α-olefin. These polypropylene resins may be used alone or in combination of two or more.

  Examples of the α-olefin used for the polypropylene resin include compounds similar to the α-olefin used for the ethylene-α-olefin copolymer.

<Modified polyolefin resin>
For example, the modified polyolefin resin is obtained by modifying a polyolefin with a modifying compound such as maleic anhydride, dimethyl maleate, diethyl maleate, acrylic acid, methacrylic acid, tetrahydrophthalic acid, glycidyl methacrylate, hydroxyethyl methacrylate, or methyl methacrylate. can get. The polyolefin used here may be a known polyolefin. For example, ethylene-based resin, isotactic polypropylene, syndiotactic polypropylene, random type polypropylene containing a comonomer, block type polypropylene by multistage polymerization, poly (4-methyl- 1-pentene), poly (1-butene) and the like.

As a method for producing polyolefin, a known polymerization method using a known catalyst for olefin polymerization is used. For example, slurry polymerization method, solution polymerization method, bulk polymerization method, gas phase polymerization method, etc. using complex catalysts such as Ziegler-Natta catalysts, metallocene complexes and nonmetallocene complexes, and radical initiators are used. Examples thereof include bulk polymerization and solution polymerization.
Commercially available polyolefins may also be used, and examples thereof include polypropylene resin “Nobrene FLX80E4” manufactured by Sumitomo Chemical Co., Ltd.

  The thermoplastic resin and polyolefin include other components as necessary, for example, a light diffusing agent, an antioxidant, an ultraviolet absorber, an organic dye, an inorganic dye, a pigment, an antistatic agent, a surfactant, and the like. May be blended.

  The melt-kneaded thermoplastic resin and polyolefin are melt-coextruded to form a film, and the film is inserted between a shaping roll and a touch roll and formed into a laminate. Hereinafter, the manufacturing method of the present invention will be described in detail with reference to FIG.

FIG. 1 is a schematic explanatory view showing one embodiment of the production method of the present invention.
As shown in the figure, in this embodiment, the thermoplastic resin and polyolefin charged in the extruders 1 and 2 are melt-kneaded and supplied to the distribution block 3 and distributed so as to have a desired layer structure. Thereafter, they are stacked in a multi-manifold die 4 (T-die) and extruded from the tip of the multi-manifold die 4 as a film.

  In the present embodiment, a polyolefin layer is usually laminated and integrated with a thermoplastic resin layer by an in-die lamination method. Specifically, for example, the thermoplastic resin and polyolefin supplied to the distribution block 3 that is a two-type three-layer or two-type two-layer distribution type have a polyolefin layer arranged on both sides of the thermoplastic resin layer in the distribution block 3. Or distributed so that the polyolefin layer is disposed on one surface of the thermoplastic resin layer, laminated in the multi-manifold die 4 and integrated as a three-layer structure or a two-layer structure.

The temperature settings of the extruder 1, the extruder 2 and the multi-manifold die 4 may be adjusted as appropriate depending on the resin used. However, when a polycarbonate resin is used as the thermoplastic resin and a polyethylene resin is used as the polyolefin, the extruder 1 is 220. It is preferable that the extruder 2 is 210 to 300 ° C, and the multi-manifold die 4 is 260 to 300 ° C. When a polycarbonate resin is used as the thermoplastic resin and a polypropylene resin is used as the polyolefin, the extruder 1 is 210-290 ° C., the extruder 2 is 210-280 ° C., and the multi-manifold die 4 is 250-290 ° C. Is preferred.
If the temperature setting of the extruder 1, the extruder 2 or the multi-manifold die is out of the above range, the polyethylene resin may become a foreign matter due to gelation due to crosslinking. There is a fear.

  In the present embodiment, the multi-manifold method using the distribution block 3 and the multi-manifold die 4 is used, but instead of this, for example, a dual-slot die that is a feed block stacking method or an external die stacking method is used. be able to. Among these, it is preferable to use a multi-manifold system because the thickness accuracy of each layer is more excellent.

  Next, the film-like material extruded from the multi-manifold die 4 is molded with the touch roll 5 (cooling roll) arranged opposite to the horizontal direction as the side on which the polyolefin layer surface comes into contact with the shaping roll 6 (cooling roll). The mat shape is transferred between the rolls 6 and transferred onto the surface of the polyolefin layer. At the same time, the mat shape is transferred onto the surface of the thermoplastic resin layer in contact with the polyolefin layer through the polyolefin layer to form a laminate. The At this time, a mat shape is also formed on the polyolefin layer surface in contact with the thermoplastic resin layer surface. Further, the laminate wound around the shaping roll 6 is passed between the shaping roll 6 and the mirror surface roll 7 (cooling roll), and is gently cooled by the mirror surface roll 7 and laminated at a predetermined take-up speed. The body 8 can be obtained.

The touch roll 5 usually has a diameter of about 200 to 1000 mm, and is made of, for example, a rubber roll or a metal elastic roll.
What is necessary is just to adjust the temperature of the touch roll 5 suitably with resin to be used, for example, when using a polycarbonate-type resin for a thermoplastic resin and a polyethylene-type resin for polyolefin, it is 10-160 degreeC normally, Preferably it is 15-150 degreeC. . Moreover, when using a polycarbonate-type resin for a thermoplastic resin and a polypropylene-type resin for polyolefin, it is 10-170 degreeC normally, Preferably it is 15-160 degreeC.
If the temperature of the touch roll 5 is too low, the resin is rapidly cooled, so that the laminate 8 is likely to remain distorted. If the temperature of the touch roll 5 is too high, the cooling is insufficient. The laminated body 8 may be tightly wound on the roll and wound up.

Examples of the rubber roll include a silicone rubber roll, a fluororubber roll, and a rubber roll mixed with sand to improve releasability.
The hardness of the rubber roll is preferably in the range of A60 ° to A90 ° measured according to JIS K6253. In order to make the hardness of the rubber roll within the above range, for example, it can be arbitrarily performed by adjusting the degree of crosslinking and composition of the rubber constituting the rubber roll.

  As the metal elastic roll, for example, the inside of the roll is made of rubber or a fluid is injected, and the outer peripheral part is made of a metal thin film having flexibility. is there. Specifically, the inside of the roll is composed of a silicone rubber roll, and a cylindrical stainless steel thin film having a thickness of about 0.2 to 1 mm is coated on the outer periphery of the roll, In a case where a fluid such as oil is injected, a cylindrical thin film made of stainless steel having a thickness of about 2 to 5 mm is fixed at the end of the roll, and the fluid is sealed inside.

  As such a touch roll 5, for example, a touch roll 5 made of a metal material or an elastic body and finished in a mirror shape with a plating or the like is used. The surface of the metal thin film or rubber roll of the metal elastic roll is not necessarily smooth, and there is no problem even if a mat shape is provided on the surface in the same manner as the shaping roll 6 described below.

The shaping roll 6 usually has a diameter of about 200 to 1000 mm, and is made of, for example, a metal roll having a mat shape formed on the outer peripheral surface.
What is necessary is just to adjust the temperature of the shaping roll 6 suitably with resin to be used, for example, when using a polycarbonate-type resin for a thermoplastic resin and a polyethylene-type resin for polyolefin, it is 10-80 degreeC normally, Preferably it is 20-60 degreeC. is there. Moreover, when using a polycarbonate-type resin for a thermoplastic resin and a polypropylene-type resin for polyolefin, it is 10-100 degreeC normally, Preferably it is 20-80 degreeC.
When the temperature of the shaping roll 6 is too low, the resin is rapidly cooled, so that the laminate 8 is likely to remain distorted. When the temperature of the shaping roll 6 is too high, the cooling is insufficient. As a result, the laminate 8 may be in close contact with the roll and wound up.

  Examples of the shaping roll 6 include a drilled roll obtained by shaving a metal lump, a metal roll capable of controlling the temperature of the roll surface through fluid, steam, etc. inside the roll such as a spiral roll having a hollow structure. A roll having a desired mat shape formed on the outer peripheral surface of the roll by sandblasting or engraving can be used.

  In the forming roll 6, the maximum height (Rz) of the contour curve on the outer peripheral surface and the average length (RSm) of the contour curve elements satisfy the relationship of 0.2 ≦ Rz / RSm ≦ 1.0. It is more preferable to satisfy the relationship of 3 ≦ Rz / RSm ≦ 1.0. When the shaping roll 6 satisfies the above predetermined relationship between Rz and RSm, the mat shape is sufficiently transferred to the surface of the thermoplastic resin layer in contact with the polyolefin layer, and the thermoplastic resin layer surface (mat surface) A laminate having a high surface haze is obtained. When the value of Rz / RSm is less than 0.2, it becomes difficult to transfer the mat shape to the surface of the thermoplastic resin layer in contact with the polyolefin layer through the polyolefin layer, and to the surface of the thermoplastic resin layer on the mat surface. It is impossible to obtain a laminate having a high noise. Moreover, when the value of Rz / RSm exceeds 1.0, it is difficult to produce a shaping roll having such a mat shape on the outer peripheral surface.

The maximum height (Rz) of the contour curve is an index indicating the depth of the mat-shaped unevenness, and the value of Rz increases as the unevenness depth increases, and the value of Rz decreases as the unevenness depth decreases. . The average length (RSm) of the contour curve element is an index indicating the average interval of the mat-shaped unevenness, and the longer the unevenness interval, the larger the value of RSm, and the shorter the unevenness interval, the smaller the value of RSm.
The maximum height (Rz) of the contour curve and the average length (RSm) of the contour curve elements are measured according to, for example, a surface roughness meter (Surf Test SJ-201 manufactured by Mitutoyo Corporation) according to JIS B0601-2001. )), The evaluation length can be measured as 4 mm, the cut-off value as 0.8 mm, and the measurement direction as the width direction of the shaping roll 6.

  The surface haze on the mat surface of the thermoplastic resin layer is usually affected by the mat shape of the mat surface, and the mat shape has a large unevenness and a large Rz value. The smaller the value of, the higher the surface haze. In order to obtain a laminate having a high haze on the surface of the mat of the thermoplastic resin layer, the Rz value is large also on the outer peripheral surface of the shaping roll 6 for transferring and forming the mat surface of the thermoplastic resin layer, and It is sufficient that the value of RSm is small, and when Rz / RSm calculated from Rz and RSm is 0.2 or more, a laminate having a high surface haze on the mat surface of the thermoplastic resin layer is obtained.

  The maximum height (Rz) of the contour curve is preferably 10 to 50 μm, more preferably 15 to 40 μm. The average length (RSm) of the contour curve element may be set as appropriate so that Rz / RSm satisfies the predetermined relationship. When Rz is within the preferable range, Rz / RSm is not less than the predetermined length. It is preferable to set so as to satisfy the relationship.

  In order to set the maximum height (Rz) of the contour curve on the outer peripheral surface and the average length (RSm) of the contour curve elements of the shaping roll 6 to desired values, for example, in the production of the shaping roll, a metal roll When a desired mat shape is formed by sandblasting on the outer peripheral surface, the particle size of the powder to be blasted and its blasting pressure may be set as appropriate.

The film-like material extruded from the multi-manifold die 4 is a film-like material in which a polyolefin layer is laminated on both sides of the thermoplastic resin layer, and is in contact with the polyolefin layer through the polyolefin layer. When transferring the mat shape to the resin layer surface, or a film-like product in which a polyolefin layer is laminated on one surface of the thermoplastic resin layer, the thermoplastic resin layer surface in contact with the polyolefin layer through the polyolefin layer When forming the mat shape, the mat shape of the shaping roll 6 is transferred to the surface of the thermoplastic resin layer by being sandwiched between the touch roll 5 and the shaping roll 6 and molded into the laminate 8. . In that case, it extrudes so that the polyolefin layer surface of a film-form thing may contact with the shaping roll 6. FIG.
In the case of a film-like product in which a polyolefin layer is laminated on both surfaces of a thermoplastic resin layer, and the mat shape is formed on both surfaces of the thermoplastic resin layer over the polyolefin layer, the mat shape is arranged on the outer peripheral surface. What is necessary is just to pinch | interpose this film-like thing between the cooling rolls formed in this.

The laminated body 8 to which the mat shape is transferred is wound around the shaping roll 6 and then taken up and taken up by the take-up roll.
The take-up speed of the take-up roll may be appropriately adjusted depending on the resin used, and is usually 0.5 to 80 m / min, preferably 2 to 60 m / min. If it is slower than 0.5 m / min, it may be disadvantageous in terms of production cost, and if it is faster than 80 m / min, there is a risk that in-line film appearance inspection assuming an optical application will be insufficient.
At this time, the mirror roll 7 may be provided after the shaping roll 6. Thereby, since the laminated body 8 is cooled slowly, the optical distortion of the laminated body 8 can be reduced, and furthermore, the contact time to the shaping roll 6 can be stably secured. The mat shape thus formed can be stably transferred. The mirror roll 7 is not particularly limited, and a normal metal roll conventionally used in extrusion molding can be employed. Specific examples include a drilled roll and a spiral roll. The surface state of the mirror surface roll 7 is preferably a mirror surface.

  The laminate 8 wound around the shaping roll 6 is passed between the shaping roll 6 and the mirror roll 7 so as to be wound around the mirror roll 7. A predetermined gap may be provided between the shaping roll 6 and the mirror roll 7 so as to be in a released state or may be sandwiched between both rolls. In order to cool the laminate 8 more gently, one or a plurality of cooling rolls are provided after the mirror roll 7, and the mat film wound around the mirror roll 7 is sequentially wound around the next cooling roll. May be.

  In addition, in the laminated body in which the thermoplastic resin layer or the polyolefin layer has a multilayer structure, another extruder (not shown) is newly provided in addition to the extruders 1 and 2 shown in FIG. A seed 3 layer distribution type block or a 3 type 5 layer distribution type block may be used, and the others may be co-extruded in the same manner as in the embodiment described above.

  The laminate obtained by the production method of the present invention is obtained by laminating a polyolefin layer on the mat surface of a thermoplastic resin layer, and an adhesive or a pressure-sensitive adhesive is interposed between the thermoplastic resin layer and the polyolefin layer. These two layers are in contact with each other.

  In the laminate, the thermoplastic resin layer and the polyolefin layer can be peeled off. The thermoplastic resin layer obtained by peeling the polyolefin layer from the laminate can be used as the above-mentioned mat film, and the polyolefin layer functions as the above-mentioned protective film. In addition, peelable means that the other layer can be peeled off from one layer of the laminated thermoplastic resin layer and polyolefin layer and separated into separate layers.

  The thickness of the laminate is 30 to 400 μm, preferably 50 to 300 μm, and more preferably 70 to 250 μm. If the thickness is less than 30 μm, the rigidity of the laminate itself becomes low, so that wrinkles are likely to enter the laminate, and floating or the like tends to occur in the set state. When the thickness is thicker than 400 μm, the manufacturing cost of the laminate is increased, and when the obtained laminate is bonded to the polarization separation sheet, the thickness of the polarization separation sheet after bonding is increased, and as a result The liquid crystal panel may become thick, which is not preferable.

In the laminate, the thickness of the thermoplastic resin layer is preferably 60% or more of the thickness of the entire laminate, more preferably 70% or more, and 80% or more. More preferably, the thickness is When the thickness of the thermoplastic resin layer is less than 60% with respect to the total thickness of the laminate, for example, when the mat shape is transferred to the thermoplastic resin layer through the polyolefin layer, the thermoplastic resin layer is sufficient. May not be able to transfer a proper mat shape.
Moreover, it is preferable that the thickness of a polyolefin layer is 5-50 micrometers, and it is more preferable that it is 10-40 micrometers. If the thickness is larger than 50 μm, for example, when transferring the mat shape to the thermoplastic resin layer through the polyolefin layer, there is a possibility that a sufficient mat shape cannot be transferred to the thermoplastic resin layer, and if it is less than 5 μm, the polyolefin layer There is a possibility that the protective function as a protective film may be reduced or the film may be broken during peeling.

  Moreover, it is preferable that the haze of the thermoplastic resin layer after peeling a polyolefin layer from a laminated body is 90% or less. If the haze is lower than 25%, a sufficient antiglare effect may not appear. On the other hand, if it exceeds 90%, when this film is used in a liquid crystal display device, the screen may be tinted and image quality may be deteriorated.

The in-plane retardation value of incident light at a wavelength of 590 nm of the thermoplastic resin layer is preferably 30 nm or less, and more preferably 20 nm or less.
For example, when the thermoplastic resin layer from which the polyolefin layer in the present invention is peeled is used in a liquid crystal display device, since the light used for the liquid crystal display is polarized light, a film having a small optical distortion is required, and the retardation is 30 nm or less. It is preferably a value. When using the thermoplastic resin layer as a polarizing separation sheet protective film used for polarizing separation sheet protection among liquid crystal display devices, the retardation value is set so as not to disturb the polarization direction of polarized light emitted from the polarizing separation sheet as much as possible. Is preferably low, and the retardation value is more preferably 20 nm or less.

  The 60 ° specular glossiness on the mat surface of the thermoplastic resin layer is preferably 60% or less, and more preferably 50% or less. If the 60-degree specular gloss exceeds 60%, a rainbow pattern due to interference may occur when the thermoplastic resin layer comes into contact with the liquid crystal panel.

In the surface roughness of the mat surface of the thermoplastic resin layer, the arithmetic average roughness (Ra) is preferably 0.2 to 6 μm, more preferably 0.7 to 6 μm, and the maximum contour curve. The height (Rz) is preferably 0.7 to 30 μm, more preferably 3 to 30 μm, and the average length (RSm) of the contour curve element is preferably 80 to 320 μm. More preferably, it is -300 micrometers. If each of the roughness values is lower than a predetermined range, a sufficient antiglare effect may not appear. Moreover, when it exceeds each predetermined range, there exists a possibility that transparency may fall.
Rz and RSm of the mat surface of the thermoplastic resin layer preferably satisfy the relationship of Rz / RSm ≧ 0.05 from the viewpoint of increasing the haze on the surface. To set Rz / RSm on the mat surface of the thermoplastic resin layer to a desired value, when Rz / RSm on the mat surface of the thermoplastic resin layer is Y and Rz / RSm on the outer peripheral surface of the shaping roll is X Rz / RSm on the outer peripheral surface of the shaping roll may be adjusted so that the relationship of Y ≧ 0.25X is satisfied.

In the laminate, the delamination force between the thermoplastic resin layer and the polyolefin layer is preferably 1 to 50 g / 25 mm width, more preferably 1 to 30 g / 25 mm width, and 1 to 10 g / 25 mm width. More preferably.
If the delamination force is lower than 1 g / 25 mm width, the polyolefin layer may be peeled off from the laminate when an external force is applied during winding of the laminate, during transportation, or even during cutting. From 50 g / 25 mm width If it is too high, the thermoplastic resin layer may be damaged when the polyolefin layer is peeled off.

The thermoplastic resin layer from which the polyolefin layer is peeled off from the laminate has a high surface haze on the matte surface, and is intended to protect the surface of the film by diffusion, bending, anti-sticking and contact with other members, etc. In a liquid crystal display device, used as the above-mentioned mat film, for example, a light diffusion sheet, a light diffusion film, a polarizing plate protective film, a retardation film, a brightness enhancement film, a reflection film, a light guide plate or a polarized light incorporated in a backlight unit Used as a separation sheet protective film. Among these, the use as a polarizing separation sheet protective film is preferable.
In order to use a thermoplastic resin layer as a polarizing separation sheet protective film, first, a polyolefin layer laminated on the mat surface of the thermoplastic resin layer is peeled off from the mat surface to obtain a thermoplastic resin layer, and then obtained. The thermoplastic resin layer may be bonded to at least one surface of the polarization separation sheet. When one surface of the thermoplastic resin layer is a mat surface, the mat surface may be the outermost surface, that is, a surface that is not the mat surface may be bonded to the polarization separation sheet. When the surface is a mat surface, either one of the mat surfaces may be bonded to the polarization separation sheet. Further, the thermoplastic resin layer bonded to the polarization separation sheet may cause scratches on the mat surface or dust to adhere to it when bonded to the polarization separation sheet or during transportation. Therefore, first, the laminate is bonded to the polarization separation sheet so that the mat film surface of the laminate becomes the bonding surface, and then in the final stage of assembly of the liquid crystal display device, the thermoplastic resin layer in the laminate is The polyolefin layer laminated on the mat surface may be peeled off from the mat surface.

  The laminate or the thermoplastic resin layer is bonded to the polarization separation sheet by applying an adhesive or an adhesive to the lamination surface of the laminate or the thermoplastic resin layer, and the polarization separation sheet and the laminate or the thermoplastic resin layer. It is preferable to interpose a pressure-sensitive adhesive layer or an adhesive layer between them. Moreover, you may interpose the adhesive resin layer which added the adhesive. The pressure-sensitive adhesive or adhesive is not particularly limited, and may be appropriately selected according to the required pressure-sensitive adhesive force or adhesive force.

  The thermoplastic resin layer from which the polyolefin layer is peeled off from the laminate is not limited to use in the above-mentioned liquid crystal display device, but is also applied to optical disks, automobile interior films, lighting films, building material films, and the like. be able to.

  The thermoplastic resin layer or the polyolefin layer is not limited to a single layer structure, and may have a multilayer structure of two or more layers as necessary. Examples of the thermoplastic resin layer include a two-layer structure in which a layer made of an acrylic resin and a layer made of a polycarbonate resin are laminated.

  Examples of the present invention will be described below, but the present invention is not limited thereto.

The structure of the extrusion apparatus used in the following examples and comparative examples is as follows.
Extruder 1: Single screw extruder with vented screw diameter 65mm (manufactured by Toshiba Machine Co., Ltd.)
Extruder 2: Single screw extruder with vented screw diameter 45mm (manufactured by Toshiba Machine Co., Ltd.)
Distribution block 3: 2-type, 2-layer distribution block (manufactured by Toshiba Machine Co., Ltd.)

  Extruders 1 and 2, a distribution block 3, a multi-manifold die 4, a touch roll 5, a shaping roll 6, and a mirror roll 7 were arranged as shown in FIG.

  The touch roll 5, the shaping roll 6, and the mirror roll 7 will be specifically described. As the touch roll 5, a silicone rubber roll having an outer diameter of 250 mmφ and a hardness of A70 ° was used. In Example 1, the shaping roll 6 has an outer diameter of 250 mmφ and a matt shape formed on the outer peripheral surface by blasting. The maximum contour curve height (Rz) on the outer peripheral surface is 25.4 μm. In Comparative Example 1, a matte shape is formed by blasting the outer peripheral surface with an outer diameter of 250 mmφ using a stainless steel shaping roll 61 (drilled roll) having a length (RSm) of 105 μm and Rz / RSm = 0.24. Formed roll 62 made of stainless steel having a maximum contour curve height (Rz) of 15.6 μm, an average contour curve element length (RSm) of 100 μm, and Rz / RSm = 0.16. (Drilled roll) was used. As the mirror roll 7, a stainless steel metal roll (drilled roll) having an outer diameter of 250 mmφ and a mirror finish was used. The maximum height (Rz) of the contour curve on the outer peripheral surface and the average length (RSm) of the contour curve elements of the shaping roll 61 and the shaping roll 62 are measured with a surface roughness meter ("Surf Test" manufactured by Mitutoyo Corporation). SJ-201 "), the evaluation length was 4 mm, the cutoff value was 0.8 mm, the measurement direction was the width direction of the shaping roll, and the measurement was performed according to JIS B0601-2001.

The resins used in the examples and comparative examples are the following two types.
Resin 1: Polycarbonate resin “Caliver 300-15” manufactured by Sumitomo Dow Co., Ltd.
Resin 2: Polypropylene resin “Noblen W151” manufactured by Sumitomo Chemical Co., Ltd.

Example 1
As the thermoplastic resin layer, the resin 1 is melted and supplied to the distribution block 3 from the extruder 1 (cylinder temperature: 230 to 260 ° C., screw rotation speed: 40 rpm, extrusion rate: 50 kg / hour), and the polyolefin layer is used as the resin. 2 is melted and supplied to the distribution block 3 from the extruder 2 (cylinder temperature: 210 to 265 ° C., screw rotation speed: 29 rpm, extrusion rate 7 kg / hour), and the thermoplastic resin layer / polyolefin layer of the distribution block 3 is supplied. After being distributed so as to have a two-layer structure, it was laminated with a multi-manifold die 4 (die temperature: 260 ° C.) to extrude a film-like material.

  The film-like material extruded from the multi-manifold die 4 is formed with the touch roll 5 (set temperature: 35 ° C.) and the shaping roll 61 (set temperature: 35 ° C.) so that the polyolefin layer surface comes into contact with the shaping roll 61. The laminate was molded by sandwiching them. Furthermore, the laminated body wound around the shaping roll 61 is passed between the shaping roll 61 and the mirror surface roll 7 and is wound around the mirror surface roll 7 (set temperature: 50 ° C.) at a take-up speed of 10 m / min. The laminate 8 having a two-layer structure having a total thickness of 160 μm in which a polyolefin layer having a thickness of 30 μm was laminated on one surface of a thermoplastic resin layer having a thickness of 130 μm and the surface of the polyolefin layer being a mat surface was obtained. In the obtained laminate 8, no wrinkles were found in the polyolefin layer. The thermoplastic resin layer after peeling the polyolefin layer from the laminate 8 had no adhesive residue on the surface in contact with the polyolefin layer, and the surface was a matte surface. The polyolefin layer peeled from the laminate had a matte surface on both sides.

(Comparative Example 1)
A polyolefin layer having a thickness of 30 μm is laminated on one surface of a thermoplastic resin layer having a thickness of 130 μm in the same manner as in Example 1 except that the shaping roll 62 is used as the shaping roll 6. A laminate 8 having a two-layer structure with a total thickness of 160 μm and having a matte surface was obtained. In the obtained laminate 8, no wrinkles were found in the polyolefin layer. The thermoplastic resin layer after peeling the polyolefin layer from the laminate 8 had no adhesive residue on the surface in contact with the polyolefin layer, and the surface was a matte surface. The polyolefin layer peeled from the laminate had a matte surface on both sides.

<Peel strength>
In an atmosphere at 23 ° C., the force required to peel the polyolefin layer from the obtained laminate was measured under the conditions of a peel width of 25 mm, a peel angle of 180 °, and a peel speed of 300 mm / min. (G / 25 mm).

  The following evaluation was performed about the thermoplastic resin layer which peeled the polyolefin layer from each obtained laminated body. The results are shown in Table 1.

<Retardation value>
A test piece was cut out from the thermoplastic resin layer with a size of 50 mm square, and a retardation value at 590 nm was measured with a micro-area birefringence meter (“KOBRA-CCO / X” manufactured by Oji Scientific Instruments).

<Total light transmittance (Tt) and haze (H)>
Based on JIS K7361-1, the total light transmittance (Tt) of the thermoplastic resin layer was measured.
In accordance with JIS K7136, the haze (H) of the thermoplastic resin layer was measured.

<60 degree specular gloss>
Based on JIS Z8741, the 60 degree specular glossiness of the mat surface of the thermoplastic resin layer was measured.

<Surface roughness>
The arithmetic average roughness (Ra) of the mat surface of the thermoplastic resin layer, the maximum height of the contour curve (Rz), and the average length of the contour curve element (RSm) were measured using a surface roughness meter (manufactured by Mitutoyo Corporation). Using surf test SJ-201 "), the evaluation length was 4 mm, the cut-off value was 0.8 mm, the measurement direction was the extrusion flow direction (MD direction) of the laminate, and the measurement was performed according to JIS B0601-2001. .

<Surface haze>
Apply dioctyl phthalate (DOP) to one side of Sumitomo Chemical's acrylic plate “Sumipex E000” with a thickness of 1 mm, and make sure that the non-matt side of the thermoplastic resin layer is in contact with DOP. A thermoplastic resin layer was placed thereon to obtain a laminate in which the thermoplastic resin layer and the acrylic plate were in close contact. The haze of the obtained laminate was measured according to JIS K 7136, and the obtained value was defined as the surface haze.

DESCRIPTION OF SYMBOLS 1, 2 Extruder 3 Distribution block 4 Multi manifold die 5 Touch roll 6 Shaping roll 7 Mirror roll 8 Laminated body

Claims (6)

A laminate in which a thermoplastic resin and a polyolefin are melt-coextruded to obtain a film, and the film is inserted between a shaping roll and a touch roll, and a thermoplastic resin layer and a polyolefin layer are laminated. A method of manufacturing
In the laminate, the surface of the thermoplastic resin layer in contact with the polyolefin resin layer is a mat surface,
As the shaping roll, the shaping roll in which the maximum height (Rz) of the contour curve on the outer peripheral surface and the average length (RSm) of the contour curve elements satisfy the relationship of 0.2 ≦ Rz / RSm ≦ 1.0. The manufacturing method of the laminated body characterized by using.   The manufacturing method of Claim 1 which inserts a film-like material between a shaping roll and a touch roll so that the surface of a polyolefin layer may contact a shaping roll.   The production method according to claim 1, wherein the thermoplastic resin layer and the polyolefin layer are peelable.   2. The thermoplastic resin is at least one selected from the group consisting of a polycarbonate resin, an acrylic resin, a polyester resin, a styrene resin, a methyl methacrylate-styrene resin, an ABS resin, and an AS resin. The manufacturing method in any one of -3.   The production method according to any one of claims 1 to 4, wherein the polyolefin is at least one selected from the group consisting of a polyethylene-based resin, a polypropylene-based resin, and a modified polyolefin-based resin that is a modified product thereof.   The manufacturing method according to claim 1, wherein both surfaces of the thermoplastic resin layer are mat surfaces.

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