KR102139854B1 - The transparent resin laminate - Google Patents

Abstract

(Task) It is to provide a transparent resin laminate which is suitable for a transparent substrate of a touch panel having a surface hardness on the opposite side from a surface on which a transparent conductive film is formed.
(Solution means) As the transparent resin laminate 10 on which the transparent conductive film 21 is formed on the surface 10a, the polycarbonate resin layer 1 and the transparent conductive film 21 of the polycarbonate resin layer 1 The acrylic resin layer 2 laminated on one side 1a, which is the side on which it is formed, and the other side 1b, which is on the opposite side is provided. It is preferable that the thickness of the polycarbonate resin layer 1 is 50% or more of the total thickness.

Description

Transparent resin laminate {THE TRANSPARENT RESIN LAMINATE}

The present invention relates to a transparent resin laminate in which a transparent conductive film is formed on the surface.

A touch panel is used in a car navigation system, a portable information terminal, an operation panel of an industrial machine, a screen of a personal computer, and a portable game machine. The touch panel is provided with a pair of plate-shaped transparent conductors facing each other and a dot spacer for forming a space between the transparent conductors, and when one of the transparent conductors (upper electrode) is pressed, the transparent conductive The sieve is configured to conduct electricity by contacting the other transparent conductor (lower electrode) (for example, see Patent Document 1).

The transparent conductor is usually formed by forming a transparent conductive film containing a conductive material such as tin-doped indium oxide (ITO) on the surface of a transparent substrate made of polyethylene terephthalate, polycarbonate, or the like (for example, patent literature) 1 to 3).

In the transparent substrate, excellent surface hardness is required on the back surface opposite to the surface on which the transparent conductive film is formed. That is, when the transparent conductor is used as the lower electrode, the back surface of the transparent substrate is disposed on the lower side opposite to the processing table during processing, and thus receives a physical impact from the processing table. In addition, when the transparent conductor is used as an upper electrode, the back surface of the transparent substrate is a touch surface that is touched with a finger, a touch pen, or the like, and thus is physically impacted by a touch pen or the like. Therefore, in either case of the lower electrode and the upper electrode, excellent surface hardness is required on the back surface of the transparent substrate. However, it is a reality that the conventional transparent substrates such as those described in Patent Literatures 1 to 3 have not sufficiently responded to the demand for this surface hardness.

Japanese Patent Application Publication No. 2008-302601 Japanese Patent Application Publication No. Hei 7-205385 Japanese Patent Publication No. 2001-322197

An object of the present invention is to provide a transparent resin laminate which is suitable for a transparent substrate of a touch panel having a surface hardness on the opposite side from a surface on which a transparent conductive film is formed.

As a result of repeated studies of the inventors in order to solve the above problems, the present inventors have found a solution comprising the following structures, and have come to complete the present invention.

(1) A transparent resin laminated plate on which a transparent conductive film is formed on a surface, comprising a polycarbonate resin layer and an acrylic resin layer laminated on the other side opposite to one side on which the transparent conductive film is formed on the polycarbonate resin layer. Transparent resin laminate.

(2) The transparent resin laminate according to (1) above, wherein the thickness of the polycarbonate resin layer is 50% or more of the total thickness.

(3) The transparent resin laminate according to (1) or (2), wherein the acrylic resin layer is a layer composed of a methacrylic resin and a rubbery polymer.

(4) The transparent resin laminate according to any one of (1) to (3), wherein an acrylic resin layer is laminated on one side of the polycarbonate resin layer.

(5) The transparent resin laminate according to any one of (1) to (4) above, which is used as a transparent substrate of a transparent conductor in a touch panel.

(6) The transparent resin laminate according to any one of (1) to (4) above, which is used as a transparent substrate for a lower electrode in a touch panel.

According to the transparent resin laminate of the present invention, since the surface on the opposite side from the surface on which the transparent conductive film is formed is made of an acrylic resin layer having excellent surface hardness, a surface hardness superior to that of the conventional back surface made of polyethylene terephthalate, polycarbonate, or the like is obtained. Can be obtained. In addition, since the acrylic resin layer is laminated on a polycarbonate resin layer having impact resistance, the impact resistance of the entire transparent resin laminate can be secured. Furthermore, since the refractive index of the acrylic resin is close to that of air, it is difficult to reflect light when the acrylic resin layer is stacked, and a higher light transmittance can be obtained than the polycarbonate resin monolayer.

When a transparent conductive film is formed on the surface of the transparent resin laminate, a transparent conductor can be obtained. Therefore, the transparent resin laminate of the present invention can be preferably used as a transparent substrate of a transparent conductor in a touch panel as in (5) above.

In particular, as in the above (6), it is preferable as a transparent substrate of the lower electrode subjected to physical impact during processing.

1 is a schematic cross-sectional explanatory diagram showing a transparent resin laminate according to one embodiment of the present invention.
2 is a schematic explanatory diagram showing a method of manufacturing a transparent resin laminate according to one embodiment of the present invention.
3 is a schematic cross-sectional explanatory diagram showing a transparent resin laminate according to another embodiment of the present invention.

Hereinafter, one embodiment of the transparent resin laminate according to the present invention will be described in detail with reference to FIG. 1. 1, a transparent conductive film 21 is formed on the surface 10a of the transparent resin laminate 10 according to the present embodiment. The transparent resin laminate 10 is provided with a polycarbonate resin layer 1 and an acrylic resin layer 2.

As the polycarbonate resin constituting the polycarbonate resin layer (1), for example, a resin obtained by reacting one or more divalent phenols with one or more carbonylating agents by an interfacial polycondensation method, a melt transesterification method, or a carbonate prepolymer. And resins obtained by polymerizing a cyclic carbonate compound by a ring-opening polymerization method.

Examples of the divalent 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 known as 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-diisopropyl Benzene, α,α'-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1.3-bis(4-hydroxyphenyl)-5,7-dimethyladamantane, 4,4'-dihydrate Hydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide, 4,4'-dihydroxydiphenylketone, 4,4'-dihydrate And hydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ester, and the like.

Among them, bisphenol A, 2,2-bis{(4-hydroxy-3-methyl)phenyl}propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxy Phenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)-3,3-dimethylbutane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 1,1- Bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and α,α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene. Phenol is preferably used, bisphenol A alone, bisphenol A and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, bisphenol A and 2,2 Of bis{(4-hydroxy-3-methyl)phenyl}propane and at least one divalent phenol selected from the group consisting of α,α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene Combination is more preferable.

Examples of the carbonylating agent include carbonyl halides such as phosgene, carbonate esters such as diphenyl carbonate, and haloformates such as dihaloformates of divalent phenols.

As the acrylic resin constituting the acrylic resin layer 2, methacrylic resin is generally used. The methacrylic resin may be a methyl methacrylate homopolymer of 100% by weight of methyl methacrylate unit, or may be a copolymer of methyl methacrylate and one or more other monomers copolymerizable with the methyl methacrylate. do. Especially, the resin which has a methyl methacrylate unit as a main component is preferable, Specifically, it is preferable that it is a methyl methacrylate resin containing 50 weight% or more of methyl methacrylate units, and a methyl methacrylate unit is 70 It is more preferable that it is a methyl methacrylate resin containing more than weight%.

Other monomers that can be copolymerized with the methyl methacrylate include, for example, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, benzyl methacrylate, and 2-ethyl methacrylate. Methacrylic acid esters other than methyl methacrylate, such as hexyl and 2-hydroxyethyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, 2-ethylhexyl acrylate, acrylic acid And acrylic acid esters such as 2-hydroxyethyl. Moreover, styrene and substituted styrenes, for example, halogenated styrenes, such as chlorostyrene and bromostyrene, and alkylstyrenes, such as vinyl toluene and alpha-methylstyrene, are also mentioned. Moreover, unsaturated acids, such as methacrylic acid and acrylic acid, acrylonitrile, methacrylonitrile, maleic anhydride, phenyl maleimide, cyclohexyl maleimide, etc. are also mentioned.

It is preferable that the acrylic resin layer contains a rubbery polymer. Thereby, it is possible to prevent the transparent resin laminate 10 from being easily broken. In particular, it is preferable to make the acrylic resin layer 2 into a layer composed of a methacrylic resin and a rubbery polymer by mixing the methacrylic resin and a rubbery polymer.

Examples of the rubber-like polymer include graft copolymers formed by graft polymerization of 20 to 95 parts by weight of an ethylenically unsaturated monomer such as an acrylic unsaturated monomer or an acrylic multilayer structure polymer or 5 to 80 parts by weight of a rubbery polymer. have.

It is preferable that the said acrylic multilayer structure polymer contains about 20-60 weight% of a rubber elastic layer, it is preferable to have a hard layer as an outermost layer, and it is also preferable to include a hard layer as an innermost layer.

The rubber elastic layer is preferably a layer of an acrylic polymer having a glass transition point (Tg) of less than 25°C, specifically, lower alkyl acrylate, lower alkyl methacrylate, lower alkoxyalkyl acrylate, and cyanoethyl acrylic Polymers obtained by crosslinking one or more monofunctional monomers selected from acrylate, acrylamide, hydroxy lower alkyl acrylate, hydroxy lower alkyl methacrylate, acrylic acid and methacrylic acid with polyfunctional monomers such as allyl methacrylate It is preferably a layer of. Examples of the lower alkyl group include a straight chain or branched alkyl group having about 1 to 8 carbon atoms, and examples of the lower alkoxyalkyl group include a straight chain or branched alkoxyalkyl group having about 1 to 8 carbon atoms.

The hard layer is preferably a layer of an acrylic polymer having a Tg of 25°C or higher, and specifically, a homopolymer or copolymer in which an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms is polymerized alone or as a main component is preferable. In the case where an alkyl methacrylate is used as a main component and used as a copolymer, as the copolymerization component, monofunctional monomers such as other alkyl methacrylates, alkyl acrylates, styrenes, substituted styrenes, acrylonitrile, and methacrylonitrile are used. Alternatively, a polyfunctional monomer may be added to form a crosslinked polymer.

The acrylic multilayer structure polymer is described, for example, in Japanese Patent Publication No. 55-27576, Japanese Patent Application Publication No. Hei 6-80739, Japanese Patent Application Publication No. 49-23292, and the like.

In the graft copolymer obtained by graft polymerization of 20 to 95 parts by weight of an ethylenically unsaturated monomer to the 5 to 80 parts by weight of the rubbery polymer, examples of the rubbery polymer include polybutadiene rubber and acrylonitrile/butadiene copolymer. Rubbers, diene-based rubbers such as styrene/butadiene copolymer rubbers, acrylic rubbers such as polybutylacrylate, polypropylacrylate, and poly-2-ethylhexylacrylate, and ethylene/propylene/non-conjugated diene-based rubbers are used. . Moreover, ethylene, an acrylonitrile, an alkyl (meth)acrylate, etc. are mentioned as an ethylenic monomer used for graft copolymerization to this rubbery polymer. These graft copolymers are described, for example, in Japanese Patent Application Laid-open No. 55-147514, Japanese Patent Publication No. 47-9740, and the like.

When dispersing a rubber-like polymer in an acrylic resin, it is preferable to disperse the rubber-like polymer in a proportion of 3 to 150 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the acrylic resin. When the amount of the rubbery polymer is too large, the surface hardness may decrease. In addition, when the amount of the rubbery polymer is too small, it is difficult to obtain an effect of preventing the transparent resin laminate 10 from being easily broken.

In addition, the polycarbonate resin layer 1 and the acrylic resin layer 2 are each, if necessary, for example, a light diffusing agent, a gloss removing agent, a dye, a light stabilizer, an ultraviolet absorber, an antioxidant, a release agent, a flame retardant, an antistatic agent, etc. You may add 1 or more types of additives.

Here, the above-mentioned polycarbonate resin layer 1 and the acrylic resin layer 2 both have transparency (light transmission). The "transparent" means that visible light is transmitted. Hereinafter, the description of "transparent" is defined in the same way as this. Since the transparent resin laminate 10 is made by laminating the polycarbonate resin layer 1 and the acrylic resin layer 2, it has transparency.

The above-mentioned acrylic resin layer 2 has excellent surface hardness. The acrylic resin layer 2 is laminated on one surface 1a on the side where the transparent conductive film 21 of the polycarbonate resin layer 1 is formed, and on the other surface 1b on the opposite side. Therefore, since the back surface 10b on the opposite side to the surface 10a on which the transparent conductive film 21 of the transparent resin laminate 10 is formed is made of an acrylic resin layer 2 having excellent surface hardness, the back surface 10b ) Has excellent surface hardness.

In addition, since the above-mentioned polycarbonate resin layer 1 has impact resistance, the impact resistance of the entire transparent resin laminate 10 is secured. In addition, since the refractive index of the acrylic resin is close to that of air, it is difficult to reflect light when the acrylic resin layer 2 is laminated. Therefore, the transparent resin laminate 10 can exhibit high light transmittance.

The transparent resin laminate 10 is usually sheet-shaped, and preferably 0.1 to 2 mm in thickness.

In addition, the thickness of the polycarbonate resin layer 1 is preferably 50% or more of the total thickness, more preferably 70% or more, and even more preferably 80% or more. Thereby, the impact resistance of the transparent resin laminated board 10 can be ensured, and the transparent resin laminated board 10 does not break easily.

On the other hand, if the thickness of the polycarbonate resin layer 1 relative to the overall thickness is too thin, the thickness of the acrylic resin layer 2 becomes large. The acrylic resin layer 2 is usually inferior in heat resistance to the polycarbonate resin layer 1. Therefore, when the thickness of the polycarbonate resin layer 1 relative to the total thickness becomes too thin, not only the impact resistance of the transparent resin laminate 10 is lowered, but also the heat resistance may be lowered.

The thickness of the acrylic resin layer 2 is preferably 10 µm or more, and more preferably 20 to 200 µm. If the thickness of the acrylic resin layer 2 is too thin, there is a fear that sufficient surface hardness may not be obtained. In addition, when the thickness of the acrylic resin layer 2 is too large, there is a fear that the heat resistance of the transparent resin laminate 10 is lowered.

The transparent resin laminate 10 is produced by bonding the polycarbonate resin layer 1 and the acrylic resin layer 2 through, for example, a predetermined adhesive layer, or by laminating and integrating them by coextrusion molding. Can.

When the transparent resin laminate 10 is manufactured by coextrusion molding, first, a polycarbonate resin constituting the above-described polycarbonate resin layer 1 is formed by using a two- or three-group single-screw or twin-screw extruder. After melt-kneading each of the acrylic resins constituting the acrylic resin layer 2, they are laminated through a feed block dyna multi-manifold die or the like. Subsequently, the transparent resin laminated board 10 is obtained by cooling and solidifying the sheet-shaped molten resin integrally laminated with a roll unit or the like. Hereinafter, one embodiment of manufacturing the transparent resin laminate 10 by coextrusion molding will be described in detail with reference to FIG. 2.

As shown in Fig. 2, first, the polycarbonate resin and the acrylic resin are extruded from the die 33 for coextrusion molding while being heated and melt-kneaded by separate extruders 31 and 32, respectively, and are integrally laminated. Subsequently, the sheet-shaped molten resin 34 coextruded from the die 33 is sandwiched between two cooling rolls 35 which are arranged to face each other in a substantially horizontal direction to cool. By adjusting the thickness of the molten resin 34, the interval between the two cooling rolls 35, the main speed, and the like, the thickness of the obtained transparent resin laminate 10 can be adjusted.

The cooling roll 35 is comprised of the 1st roll 36 and the 2nd roll 37. At least one of the 1st roll 36 and the 2nd roll 37 is connected to rotation drive means, such as a motor, and is comprised so that both rolls may rotate at a predetermined main speed. Of the 1st roll 36 and the 2nd roll 37, the 2nd roll 37 is a winding roll in which the sheet-like transparent resin laminated board 10 after being pinched between both rolls is wound.

Examples of the first roll 36 and the second roll 37 include a metal roll having rigidity, a metal elastic roll having elasticity, and the like. As said metal roll, a drilled roll, a spiral roll, etc. are mentioned, for example. The metal elastic roll includes, for example, an axial roll and a cylindrical thin metal film that is disposed to cover the outer circumferential surface of the axial roll and contacts the molten resin 34, and the temperature between water and oil between the axial roll and the thin metal film. Controlled fluid is enclosed, or a metal belt is wound on the surface of a rubber roll.

The 1st roll 36 and the 2nd roll 37 may consist only of a metal roll or may consist only of a metal elastic roll, or may be comprised by combining a metal roll and a metal elastic roll.

When the metal roll and the metal elastic roll are combined, a transparent resin laminate 10 with reduced strength and heat shrink anisotropy can be obtained. That is, when the molten resin 34 is sandwiched between the metal roll and the metal elastic roll, the metal elastic roll is elastically deformed into a concave shape along the outer circumferential surface of the metal roll with the molten resin 34 interposed therebetween, and the metal elastic roll and the metal The roll is brought into contact with a predetermined contact length with the molten resin 34 therebetween. Thereby, the metal roll and the metal elastic roll are pressed against the molten resin 34 by surface contact, and the molten resin 34 sandwiched between these rolls is formed into a film while being uniformly pressed in a plane shape. Since the deformation at the time of film formation is reduced by forming the film in this way, a transparent resin laminate 10 with reduced strength and heat shrink anisotropy is obtained.

Moreover, when combining a metal roll and a metal elastic roll, it is preferable to make the metal elastic roll into the 1st roll 36 and the metal roll into the 2nd roll 37. Thereby, the effect obtained by combining a metal roll and a metal elastic roll can be raised.

The sheet-like transparent resin laminate 10 after being sandwiched between the first roll 36 and the second roll 37 is wound around the second roll 37, and then harvested while being cooled on the conveying roll by a take-up roll (not shown). By this, a transparent resin laminate 10 is obtained.

On the other hand, the transparent conductive film 21 formed on the surface 10a of the transparent resin laminate 10 is a transparent film containing a conductive material, and various known ones employed in the touch panel can be employed.

The conductive material is not particularly limited, for example, indium oxide, tin-doped indium oxide (ITO), gallium-doped indium oxide, zinc-doped indium oxide, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide ( FTO), zinc oxide, aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), fluorine-doped zinc oxide, indium-doped zinc oxide, boron-doped zinc oxide, cadmium oxide, and the like.

The transparent conductive film 21 may contain a binder resin, an additive, and the like, if necessary. Examples of the binder resin include thermoplastic resins, thermosetting resins, and ultraviolet curing resins. Examples of the additives include flame retardants, ultraviolet absorbers, colorants, and plasticizers.

The thickness of the transparent conductive film 21 is preferably about 0.05 to 5 μm. The transparent conductive film 21 is, for example, a coating liquid obtained by adding the above-mentioned conductive material to a solvent, directly coated on the surface 10a, dried, or previously supported by a transparent conductive film 21 so as to be peelable on a support. Can be formed by transferring from the support to the surface 10a through a predetermined adhesive layer.

When the transparent conductive film 21 is formed on the surface 10a, a transparent conductor 20 is obtained. Therefore, the transparent resin laminate 10 is preferably used as a transparent substrate of a transparent conductor in, for example, a touch panel such as a car navigation system, a portable information terminal, an operation panel of an industrial machine, a screen of a personal computer, or a portable game machine. Can.

Since the transparent resin laminate 10 has the excellent surface hardness of the back surface 10b for the above-mentioned reason, it can be preferably used as either the lower electrode or the upper electrode in the touch panel as a transparent substrate. It can be preferably used as a transparent substrate of a lower electrode subjected to physical impact during processing.

Next, another embodiment related to the transparent resin laminate of the present invention will be described in detail with reference to FIG. 3. In Fig. 3, the same components as those in Figs. 1 and 2 described above are given the same reference numerals and description is omitted.

As shown in FIG. 3, the transparent conductive film 21 is formed on the surface 11a of the transparent resin laminated board 11 which concerns on this embodiment. Since the transparent resin laminated board 11 is provided with the polycarbonate resin layer 1 and the acrylic resin layer 2, it is the same as the transparent resin laminated board 10 according to one of the embodiments described above. 11b) has excellent surface hardness.

The transparent resin laminate 11 further includes an acrylic resin layer 3. The acrylic resin layer 3 is laminated on one surface 1a of the polycarbonate resin layer 1. When the acrylic resin layer 3 is laminated in this arrangement, the impact resistance of the transparent resin laminate 11 can be improved.

The composition and thickness of the acrylic resin layers 2 and 3 may be the same or different from each other. Moreover, the surface-impact property may fall and become easy to break|break, depending on the composition and thickness of the acrylic resin layers 2 and 3 of the transparent resin laminated board 11 of three-layer structure. Therefore, it is preferable to disperse the above-mentioned rubbery polymer in the acrylic resin layers 2 and 3. Thereby, it can suppress that the surface impact property of the transparent resin laminated board 11 falls and it is easy to be broken. Other configurations are the same as those of the transparent resin laminate 10 according to the above-described embodiment, and thus description thereof is omitted.

Hereinafter, examples of the present invention are shown, but the present invention is not limited to these. In addition, in the following Examples, the part which shows content or usage amount is a basis of weight unless otherwise specified. In addition, the structure of the extrusion apparatus used in the following Examples and Comparative Examples is as follows.

Extruder 31: screw diameter 65 mm, single axis, vent formed (manufactured by Toshiba Machinery Co., Ltd.).

Extruder 32: screw diameter 45 mm, single axis, vents are formed (manufactured by Hitachi Shipbuilding Co., Ltd.).

Feed block: 2-layer 3-layer and 2-layer 2-layer distribution (manufactured by Hitachi Shipbuilding Co., Ltd.).

Die 33: T die, lip width 1400 mm, lip spacing 1 mm (manufactured by Hitachi Shipbuilding Co., Ltd.).

Cooling rolls 35: Two cooling rolls having a horizontal shape, a face length of 1400 mm, and a diameter of 300 mmφ.

The extruders 31, 32 and the die 33 were placed as shown in Fig. 2, and the feed blocks were placed at predetermined positions. Subsequently, the first roll 36 and the second roll 37 constituting the cooling roll 35 were configured as follows.

<roll composition 1>

(Roll No. 36)

A metal thin film was disposed so as to cover the outer circumferential surface of the axial roll, and a metal elastic roll in which a fluid was sealed between the axial roll and the metal thin film was used as the first roll 36. Axial rolls, metal thin films and fluids are as follows.

Shaft roll: stainless steel.

Metal thin film: Stainless steel mirror surface metal sleeve with a thickness of 2 mm.

Fluid: With oil, temperature control of the oil made it possible to control the temperature of the metal elastic roll. More specifically, the oil was heated and cooled by ON-OFF control of the temperature controller to enable temperature control, and circulated between the axial roll and the metal thin film.

(2nd roll (37))

A spiral roll (metal roll) made of stainless steel with a mirror surface as the surface condition was used as the second roll (37).

Moreover, the contact length which the 1st roll 36 and the 2nd roll 37 contacted with the molten resin 34 in between was made into 4 mm.

<roll composition 2>

The first roll 36 and the second roll 37 were both made of stainless steel spiral rolls having the surface condition as a mirror surface.

The resins used in the following Examples and Comparative Examples are as follows.

Resin 1: A polymer of aromatic polycarbonate alone ("Calibur 301-10" manufactured by Sumitomo Dow Co., Ltd.).

Resin 2: Copolymer of methyl methacrylate/methyl acrylate = 98/2 (weight ratio).

Resin 3: An acrylic resin-based composition containing 9% by weight of an acrylic multilayer structure polymer obtained in the following Reference Example to 91% by weight of a copolymer of methyl methacrylate/methyl acrylate = 96/4 (weight ratio).

Resin 4: An acrylic resin-based composition containing 21 wt% of an acrylic multilayer structure polymer obtained in the following Reference Example to 79 wt% of a copolymer of methyl methacrylate/methyl acrylate = 96/4 (weight ratio).

[Reference example]

(Preparation of rubber-like polymer)

Based on the method described in Examples of Japanese Patent Publication No. 55-27576, an acrylic multilayer structure polymer having a three-layer structure was prepared. Specifically, first, 1700 g of ion-exchanged water, 0.7 g of sodium carbonate, and 0.3 g of sodium persulfate were added to a 5 liter glass reaction vessel, and stirred under a stream of nitrogen, followed by Perex OT-P (Kao Co., Ltd.) Preparation) 4.46 g, ion-exchanged water 150 g, methyl methacrylate 150 g, and allyl methacrylate 0.3 g were added, and the temperature was raised to 75° C. and stirring was continued for 150 minutes.

Subsequently, a mixture of 689 g of butyl acrylate, 162 g of styrene, 17 g of allyl methacrylate and 0.85 g of sodium persulfate, 7.4 g of Perex OT-P and 50 g of ion-exchanged water were added over 90 minutes from the other inlet. The polymerization was continued for 90 minutes.

After the polymerization was completed, 30 g of ion-exchanged water in which a mixture of 326 g of methyl acrylate and 14 g of ethyl acrylate and 0.34 g of sodium persulfate were dissolved was added over 30 minutes from each inlet.

After the addition was completed, the mixture was held again for 60 minutes to complete polymerization. The obtained latex was poured into a 0.5% aqueous aluminum chloride solution to aggregate the polymer. After washing this with hot water 5 times, it was dried to obtain an acrylic multilayer structure polymer.

[Examples 1 to 11]

<Production of transparent resin laminate>

As the resin layer A, the resin of the kind shown in Table 1 was melt-kneaded by the extruder 31 and supplied to the feed block. On the other hand, as the resin layer B, the resin of the kind shown in Table 1 was melt-kneaded by the extruder 32 and supplied to the feed block. Coextrusion molding was performed so that the resin layer A supplied from the extruder 31 to the feed block was the main layer, and the resin layer B supplied from the extruder 32 to the feed block was the surface layer (2nd roll 37 side). .

Then, the molten resin 34 extruded from the die 33 was film-formed while gripping the first roll 36 and the second roll 37 of the roll configurations shown in Table 1, and a two-layer structure having a thickness shown in Table 1 A transparent resin laminate made of was obtained. Moreover, the surface temperature of the 1st roll 36 was 120 degreeC, and the surface temperature of the 2nd roll 37 was 130 degreeC. These temperatures are values obtained by measuring the surface temperature of each roll. In addition, "thickness" in the extruders 31 and 32 in Table 1 shows each thickness of the resin layers A and B. "Total thickness" in Table 1 shows the total thickness of the obtained transparent resin laminate.

[Examples 12 to 22 and Comparative Example 1]

As the resin layer A, the resin of the kind shown in Table 1 was melt-kneaded by the extruder 31 and supplied to the feed block. On the other hand, as the resin layer B, the resin of the kind shown in Table 1 was melt-kneaded by the extruder 32 and supplied to the feed block. Coextrusion molding was performed so that the resin layer A supplied from the extruder 31 to the feed block was an intermediate layer, and the resin layer B supplied from the extruder 32 to the feed block was a positive surface layer.

Then, the molten resin 34 extruded from the die 33 was film-formed while being held by the first roll 36 and the second roll 37 of the roll configurations shown in Table 1 to obtain a three-layer structure having the thickness shown in Table 1. A transparent resin laminate plate was obtained. Moreover, the surface temperature of the 1st roll 36 was 110 degreeC, and the surface temperature of the 2nd roll 37 was 125 degreeC.

[Comparative Examples 2 to 4]

The resin of the kind shown in Table 1 was melt-kneaded by the extruder 31, and was supplied in the order of the feed block and the die 33. Then, the molten resin extruded from the die 33 was film-formed while being held by the first roll 36 and the second roll 37 of the roll configurations shown in Table 1, and made of a single layer structure having a thickness shown in Table 1. A transparent resin plate was obtained.

<Evaluation>

Each of the obtained transparent resin laminates and transparent resin plates (Examples 1 to 22 and Comparative Examples 1 to 4) were evaluated for pencil hardness and total light transmittance. Each evaluation method is shown below, and the results are shown in Table 1 together.

(Pencil hardness)

It measured according to JIS K5600. Moreover, the measurement surface in the transparent resin laminated boards of Examples 1-11 is resin layer B.

(Total light transmittance)

It measured according to JISK7361-1:1997 using the haze meter HM-150 (made by Murakami Color Technology Research Institute). In addition, Examples 1-11 measured the resin layer B facing the light source.

As can be seen from Table 1, it can be seen that Examples 1 to 22 show better results in pencil hardness and overall light transmittance than Comparative Examples 1 to 4.

On the other hand, with respect to the transparent resin laminate made of the two-layer structures of Examples 1 to 11, it was evaluated whether or not the laminate was bent and bent by hand (bendability). As a result, the laminated plate showed a result that it did not break well even when bent. Further, among the transparent resin laminates of Examples 12 to 22 having a three-layer structure, the laminated resins of Examples 16 to 22, in which the acrylic resin layer is a layer composed of a methacrylic resin and a rubbery polymer, were bent in the same manner as above. Was evaluated. As a result, the laminated plate showed a result that it did not break well even when bent.

1: Polycarbonate resin layer
1a: One side
1b: other side
2, 3: acrylic resin layer
10, 11: transparent resin laminate
10a, 11a: surface
10b, 11b: back side
20: transparent conductor
21: transparent conductive film
31, 32: extruder
33: die
34: molten resin
35: cooling roll
36:1 roll
37: roll 2

Claims (7)

A transparent resin laminate with a transparent conductive film formed on its surface,
It has a polycarbonate resin layer, and an acrylic resin layer laminated on the other side opposite to one side which is the side on which the transparent conductive film is formed of the polycarbonate resin layer,
The thickness of the acrylic resin layer is 60 ~ 110 ㎛,
The acrylic resin constituting the acrylic resin layer is methyl methacrylate/methyl acrylate copolymer,
Transparent resin laminate. According to claim 1,
A transparent resin laminate having a thickness of the polycarbonate resin layer of 50% or more of the total thickness. A transparent resin laminate with a transparent conductive film formed on its surface,
It has a polycarbonate resin layer, and an acrylic resin layer laminated on the other side opposite to one side which is the side on which the transparent conductive film is formed of the polycarbonate resin layer,
The thickness of the acrylic resin layer is 60 ~ 110 ㎛,
A transparent resin laminate in which the acrylic resin layer is a layer composed of methyl methacrylate/methyl acrylate copolymer and a rubbery polymer. According to claim 1,
A transparent resin laminate obtained by laminating an acrylic resin layer on one side of the polycarbonate resin layer. The method according to any one of claims 1 to 4,
A transparent resin laminate used as a transparent substrate of a transparent conductor in a touch panel. The method according to any one of claims 1 to 4,
A transparent resin laminate plate used as a transparent substrate of a lower electrode in a touch panel. delete

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