JP2009226932A - Conductive laminated film, polarizing plate, and touch panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive laminated film which can achieve a touch panel having high visibility at a high contrast, and to provide a polarizing plate and the touch panel thereof. <P>SOLUTION: The conductive laminated film includes a film which is formed of a cyclic olefinic polymer, and has a 1/4 wavelength plate function causing the in-plane phase difference of a range of 128 to 148 nm to the transmission light of a wavelength of 550 nm, a particle containing resin layer, and a transparent conductive layer in which the weight ratio of an indium oxide and a tin oxide is 95:5 to 99:1. The polarizing plate using the conductive laminated film and the touch panel having this polarizing plate are provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a conductive laminated film, a polarizing plate and a touch panel having high contrast and high visibility.

In an electronic device such as a personal digital assistant (PDA), a notebook PC, an OA device, a medical device, or a car navigation system, a touch panel having an input means on these displays is widely used.
The transparent conductive film type touch panel has a transparent base film provided with a thin film of metal oxide such as indium tin oxide or tin antimonic acid or metal such as gold, palladium, aluminum or silver as a transparent conductive film on one side of the transparent base film. These metal oxides or metal thin films have a large light reflection, so that the contrast of the liquid crystal display is remarkably lowered and the screen becomes extremely difficult to see.

As a method for solving such a problem, in Patent Document 1, two transparent conductive films (a laminated film of glass and ITO) facing each other through a first quarter-wave plate and a spacer in order from the liquid crystal display side. It has been proposed to arrange a second quarter-wave plate and a polarizing plate to increase visibility.
However, the contrast of the liquid crystal display is still insufficient only by using the touch panel having the above configuration, and the optical characteristics such as light transmittance and viewing angle compensation are inferior because the touch panel has a multilayer structure. There is a problem. In order to simplify the layer structure, a transparent conductive film with a 1/4 wavelength plate function laminated with ITO has been proposed, but when exposed to high temperatures during crystallization annealing or touch panel creation, the phase difference There was a problem that decreased. In addition, when the weight ratio of indium oxide to tin oxide is 90:10, there is a problem that crystallization does not occur even if high temperature annealing is performed, and durability is inferior.

  Japanese Patent Laid-Open No. 10-48625

  An object of this invention is to provide the electroconductive laminated film, polarizing plate, and touch panel which can obtain a high-contrast and highly visible touch panel.

  The conductive laminated film of the present invention comprises a cyclic olefin polymer obtained by (co) polymerizing a monomer containing at least one compound represented by the following formula (1), and has a wavelength of 550 nm. A film having a 1/4 wavelength plate function in which an in-plane retardation with respect to transmitted light is in the range of 128 to 148 nm, a particle-containing resin layer, and a weight ratio of indium oxide to tin oxide is 95: 5 to 99: 1. It has a transparent conductive layer.

(Wherein R ^{1 to} R ⁴ each independently represents a hydrogen atom; a halogen atom; or a monovalent organic group that may contain oxygen, nitrogen, sulfur or silicon;
R ¹ and R ² and R ³ and R ⁴ may be independently bonded to each other to form an alkylidene group,
R ¹ and R ² , R ³ and R ⁴ , and R ² and R ³ may be independently bonded to each other to form a monocyclic or polycyclic carbocyclic or heterocyclic ring,
x represents an integer of 0 to 3, and y represents 0 or 1. )

The polarizing plate of the present invention is characterized in that the conductive laminated film of the present invention is laminated on a polarizing film.
The touch panel of the present invention has the polarizing plate of the present invention.

  According to the present invention, it is possible to obtain a touch panel that does not cause reflection due to light reflection, has high contrast, and is excellent in visibility. Further, even when heat treatment in the touch panel manufacturing process is performed, a touch panel with extremely small change in phase difference and extremely small change in resistance value can be obtained.

FIG. 1 is a view for explaining the angles of the absorption axis and the optical axis of each layer in the touch panel of the present invention.

Hereinafter, the present invention will be specifically described.
The conductive laminated film of the present invention has a film having a 1/4 wavelength plate function, a particle-containing resin layer, and a transparent conductive layer, preferably a film having a 1/4 wavelength plate function / particle-containing resin layer / transparent. It has a structure in which conductive layers are stacked in this order.

<Film with 1/4 wavelength plate function>
The film having a quarter-wave plate function according to the present invention comprises a cyclic olefin polymer obtained by (co) polymerizing a monomer containing at least one compound represented by the following formula (1). A film having a quarter-wave plate function having a phase difference of 128 to 148 nm, preferably 133 to 143 nm, with respect to transmitted light having a wavelength of 550 nm. Here, the phase difference is defined by the product (Δnd) of the refractive index difference (Δn) of birefringent light and the thickness (d). By having the said phase difference, in the polarizing plate of this invention, reflected light can be prevented and there exists an effect that a high contrast touch panel is obtained.
The film having the 1/4 wavelength plate function can be suitably obtained by stretching a film obtained from a cyclic olefin polymer.

(Cyclic olefin polymer)
As a cyclic olefin polymer obtained by (co) polymerizing a monomer containing at least one compound represented by the formula (1) constituting the film having a quarter-wave plate function according to the present invention. Uses a cyclic olefin compound having a norbornene skeleton represented by the above formula (1) (hereinafter also referred to as “specific monomer”) alone or in combination of two or more, or other than cyclic olefin compounds. A copolymer obtained by further using a copolymerization monomer, ring-opening (co) polymerization or addition (co) polymerization, and then hydrogenating a double bond in the main chain is preferable.
The following formula (1 ′) represents a structural unit derived from a specific monomer, and what is obtained by polymerizing or copolymerizing the specific monomer is hereinafter also referred to as “(co) polymer”.

(Wherein (1 '), R ¹ to R ^4, x and y are the same as R ¹ to R ^4, x and y of the above formula (1).)

Specifically, the (co) polymer is preferably the following (co) polymers (i) to (iii). Among these, the hydrogenated (co) polymer described in (ii) is particularly preferable.
(I) A ring-opening (co) polymer of a specific monomer and, if necessary, a copolymerizable monomer (hereinafter also referred to as “specific ring-opening (co) polymer”).
(Ii) Hydrogenated (co) polymers of specific ring-opening (co) polymers.
(Iii) Addition (co) polymer of a specific monomer and, if necessary, a copolymerizable monomer.

(Specific monomer)
Specific examples of the specific monomer used as the raw material for the cyclic olefin polymer include the following compounds, but are not limited to these specific examples.
Bicyclo [2.2.1] hept-2-ene,
Tricyclo [4.3.0.1 ^2,5 ] -8-decene,
Tricyclo [4.4.0.1 ^2,5 ] -3-undecene,
Tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
Pentacyclo ^{[6.5.1.1 3,6 .0 2,7 .0 9,13]} -4- pentadecene,
5-methylbicyclo [2.2.1] hept-2-ene,
5-ethylbicyclo [2.2.1] hept-2-ene,
5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-methyl-5-methoxycarbonylbicyclo [2.2.1] hept-2-ene,
5-cyanobicyclo [2.2.1] hept-2-ene,
8 methoxycarbonyltetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-ethoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-n-propoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8 isopropoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-n-butoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl-8-ethoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl -8-n-propoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl-8-isopropoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl -8-n-butoxycarbonyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
5-ethylidenebicyclo [2.2.1] hept-2-ene,
8 ethylidene tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
5-phenylbicyclo [2.2.1] hept-2-ene,
8-phenyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
5-fluorobicyclo [2.2.1] hept-2-ene,
5-fluoromethylbicyclo [2.2.1] hept-2-ene,
5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-pentafluoroethylbicyclo [2.2.1] hept-2-ene,

5,5-difluorobicyclo [2.2.1] hept-2-ene,
5,6-difluorobicyclo [2.2.1] hept-2-ene,
5,5-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5-methyl-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5,5,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,5,6-tris (fluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrafluorobicyclo [2.2.1] hept-2-ene,
5,5,6,6-tetrakis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5-difluoro-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-5-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-fluoro-5-pentafluoroethyl-6,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,6-difluoro-5-heptafluoro-iso-propyl-6-trifluoromethylbicyclo [2.2.1] hept-2-ene,
5-chloro-5,6,6-trifluorobicyclo [2.2.1] hept-2-ene,
5,6-dichloro-5,6-bis (trifluoromethyl) bicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-trifluoromethoxybicyclo [2.2.1] hept-2-ene,
5,5,6-trifluoro-6-heptafluoropropoxybicyclo [2.2.1] hept-2-ene,

8-fluoro-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-fluoro-methyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8 difluoromethyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-trifluoromethyl-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8 pentafluoroethyl tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8-difluoro-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,9-difluoro-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl-8-trifluoromethyl-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9- trifluoro-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9- tris (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9,9- tetrafluoro-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9,9- tetrakis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8-difluoro-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,9-difluoro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9- trifluoro-9-trifluoromethyl-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9- trifluoro-9-trifluoromethoxy-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,8,9- trifluoro-9-pentafluoro propoxy tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-Fluoro-8-pentafluoroethyl-9,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,9-difluoro-8-heptafluoro-iso- propyl-9-trifluoromethyl-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-Chloro -8,9,9- trifluoro tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8,9-dichloro-8,9-bis (trifluoromethyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8- (2,2,2-trifluoroethoxy-carbonyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene,
8-methyl-8- (2,2,2-trifluoroethoxy-carbonyl) tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene. These may be used alone or in combination of two or more.

Among these specific monomers, in the above formula (1), R ¹ and R ³ are hydrogen atoms or 1 to 10 carbon atoms, more preferably 1 to 4, more preferably 1 to 2. R ² and R ⁴ represent a hydrogen atom; or a monovalent organic group which may contain an oxygen atom, a nitrogen atom, a sulfur atom or a silicon atom, and R ² and R ⁴ At least one represents a monovalent organic group having a polarity other than a hydrogen atom or a hydrocarbon group, x represents an integer of 0 to 3, y represents an integer of 0 to 3, more preferably x + y = 0-4, more preferably 0-2, particularly preferably x = 0, y = 1, the cyclic olefin polymer obtained has a high glass transition temperature and mechanical strength. It is preferable at the point which becomes excellent.

  Examples of the monovalent organic group having the polarity include a carboxyl group, a hydroxyl group, an alkoxycarbonyl group, an allyloxycarbonyl group, an amino group, an amide group, and a cyano group. These monovalent organic groups having polarity may be bonded via a linking group such as a methylene group. In addition, a hydrocarbon group or the like in which a divalent organic group having polarity such as a carbonyl group, an ether group, a silyl ether group, a thioether group, or an imino group is bonded as a linking group is also exemplified. Among these, a carboxyl group, a hydroxyl group, an alkoxycarbonyl group, and an allyloxycarbonyl group are preferable, and an alkoxycarbonyl group and an allyloxycarbonyl group are more preferable.

Furthermore, in the above formula (1), a monomer in which at least one of R ² and R ⁴ represents a monovalent organic group having a polarity represented by the formula: — (CH ₂ ) _n COOR is a cyclic product. The olefin polymer is preferable in that it has a high glass transition temperature, low hygroscopicity, and excellent adhesion to various materials. In the formula, R represents a hydrocarbon group having 1 to 12 carbon atoms, preferably 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms, desirably an alkyl group. In addition, n is usually an integer of 0 to 5, but the smaller the value of n, the higher the glass transition temperature of the resulting cyclic olefin polymer, which is preferable, and the specific unit amount where n is 0. The body is preferred because it is easy to synthesize.

In the above formula (1), R ¹ or R ³ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 2 carbon atoms, and further preferably a methyl group. In particular, it is obtained that such an alkyl group is bonded to the same carbon atom as the carbon atom to which the monovalent organic group having the polarity represented by the above formula: — (CH ₂ ) _n COOR is bonded. This is preferable in that the hygroscopicity of the cyclic olefin polymer can be lowered.

(Copolymerizable monomer)
Specific examples of the copolymerizable monomer in the ring-opening (co) polymer include cycloolefins such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, and dicyclopentadiene. As a carbon atom number of a cycloolefin, 4-20 are preferable and 5-12 are more preferable. These may be used alone or in combination of two or more.
The copolymerizable monomer in the addition (co) polymer is preferably a compound having a reactive unsaturated double bond, specifically, an olefinic compound such as ethylene, propylene, and butene; And vinyl unsaturated hydrocarbon compounds such as α-methylstyrene and vinylcyclopentene; and (meth) acrylates such as methyl methacrylate.

(Ring-opening polymerization catalyst)
The ring-opening (co) polymerization reaction is performed in the presence of a metathesis catalyst. As this metathesis catalyst, a known catalyst can be used. For example, (a) at least one selected from W, Mo and Re compounds, and (b) a Deaming periodic table group IA element (for example, Li, Na, K, etc.), Group IIA elements (eg, Mg, Ca, etc.), Group IIB elements (eg, Zn, Cd, Hg, etc.), Group IIIA elements (eg, B, Al, etc.), Group IVA elements (eg, Si, Sn, Pb, etc.) or a compound of group IVB elements (for example, Ti, Zr, etc.), and at least one selected from those having at least one of the element-carbon bond or the element-hydrogen bond A catalyst composed of a combination. In this case, alcohols, aldehydes, ketones, amines and the like can be suitably used to increase the activity of the catalyst, but further, JP-A-1-132626, page 8, lower right column, page 16. It is also possible to use the compounds shown in line 17 to page 17, upper left column, line 17.

(Solvent for polymerization reaction)
Examples of the solvent used in the ring-opening (co) polymerization reaction (solvent constituting the molecular weight modifier solution, solvent for the specific monomer and / or metathesis catalyst) include pentane, hexane, heptane, octane, nonane, decane, etc. Alkanes; cycloalkanes such as cyclohexane, cycloheptane, cyclooctane, decalin, norbornane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene; chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylenedi Halogenated alkanes and aryl halides such as bromide, chlorobenzene, chloroform and tetrachloroethylene; saturated carboxylic acid esters such as ethyl acetate, n-butyl acetate, iso-butyl acetate, methyl propionate and dimethoxyethane; Ether, tetrahydrofuran, include such ethers such as dimethoxyethane, they may be used in combination of two or more types may be used alone. Of these, aromatic hydrocarbons are preferred.
As the amount of the solvent used, “solvent: specific monomer (weight ratio)” is usually in an amount of 1: 1 to 10: 1, preferably in an amount of 1: 1 to 5: 1. The

  The molecular weight of the resulting ring-opening (co) polymer can be adjusted depending on the polymerization temperature, the type of catalyst, and the type of solvent. For example, ethylene, propene, 1-butene, 1-pentene, 1-hexene. Further, α-olefins such as 1-heptene, 1-octene, 1-nonene, and 1-decene, and a molecular weight regulator such as styrene may be added.

  The ring-opening (co) polymer obtained as described above can be used as it is, but (iii) hydrogen obtained by hydrogenating an olefinically unsaturated bond in the molecule of this (co) polymer. Additive (co) polymers are preferred because they are excellent in heat-resistant coloring and light resistance and can improve the durability of a film having a quarter-wave plate function.

(Hydrogenation catalyst)
For the hydrogenation reaction, a method of hydrogenating a normal olefinically unsaturated bond can be applied. That is, a hydrogenation catalyst is added to a ring-opening (co) polymer solution, and hydrogen gas at normal pressure to 300 atm, preferably 3 to 200 atm, acts at 0 to 200 ° C., preferably 20 to 180 ° C. Is done by letting

As a hydrogenation catalyst, what is used for the hydrogenation reaction of a normal olefinic compound can be used. Examples of the hydrogenation catalyst include heterogeneous catalysts and homogeneous catalysts.
Examples of the heterogeneous catalyst include a solid catalyst in which a noble metal catalyst material such as palladium, platinum, nickel, rhodium, and ruthenium is supported on a carrier such as carbon, silica, alumina, and titania. In addition, homogeneous catalysts include nickel naphthenate / triethylaluminum, nickel acetylacetonate / triethylaluminum, cobalt octenoate / n-butyllithium, titanocene dichloride / diethylaluminum monochloride, rhodium acetate, chlorotris (triphenylphosphine) rhodium. Dichlorotris (triphenylphosphine) ruthenium, chlorohydrocarbonyltris (triphenylphosphine) ruthenium, dichlorocarbonyltris (triphenylphosphine) ruthenium, and the like. The form of the catalyst may be powder or granular.

The hydrogenation rate of the hydrogenated (co) polymer is 50% or more, preferably 90% or more, more preferably 98% or more, and most preferably 99% or more, as measured by 500 MHz and ¹ H-NMR. The higher the hydrogenation rate, the better the stability to heat and light. When used as the transparent film of the present invention, stable characteristics can be obtained over a long period of time.
In addition, when the ring-opening (co) polymer molecule has an aromatic group, the aromatic group is less likely to deteriorate the heat resistance coloring property and light resistance, and conversely, optical characteristics such as refractive index and wavelength dispersion. The optical properties such as the above or heat resistance may be brought about, and hydrogenation is not necessarily required.

  The ring-opening (co) polymer obtained as described above includes known antioxidants such as 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3, 3′-di-t-butyl-5,5′-dimethyldiphenylmethane, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and / or UV absorbers such as 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, etc. Can be stabilized. Further, additives such as a lubricant can be added for the purpose of improving processability.

The hydrogenated (co) polymer used as the cyclic olefin polymer preferably has a gel content contained in the hydrogenated (co) polymer of 5% by weight or less, preferably 1% by weight. The following is more preferable.
Further, as the cyclic olefin polymer, a (co) polymer obtained by cyclization of the ring-opened (co) polymer by Friedel-Craft reaction and then hydrogenation is also used.

(Addition polymerization catalyst)
As the catalyst for synthesizing the addition (co) polymer, a known catalyst can be used, specifically, at least one selected from the group consisting of a titanium compound, a zirconium compound and a vanadium compound, and an assistant. It is an organoaluminum compound as a catalyst.

(Physical properties of cyclic olefin polymers)
The molecular weight of the cyclic olefin polymer is intrinsic viscosity [η] _inh , preferably 0.2 to 5 dl / g, more preferably 0.3 to 3 dl / g, and still more preferably 0.4 to 1.5 dl / g. The number average molecular weight (Mn) in terms of polystyrene measured by gel permeation chromatography (GPC) is preferably 8,000 to 100,000, more preferably 10,000 to 80,000, still more preferably The weight average molecular weight (Mw) is preferably 20,000 to 300,000, more preferably 30,000 to 250,000, and even more preferably 40,000 to 200,000. A range is preferred.
When the intrinsic viscosity [η] _inh , number average molecular weight and weight average molecular weight are within the above ranges, the heat resistance, water resistance, chemical resistance, mechanical properties of the cyclic olefin polymer, and the conductive laminated film of the present invention As a result, the balance with the stability of the optical properties when used as a good is obtained.

The glass transition temperature (Tg) of the cyclic olefin polymer is usually 120 ° C. or higher, preferably 120 to 350 ° C., more preferably 130 to 250 ° C., and further preferably 140 to 200 ° C. This is to stabilize the change in optical properties of the obtained cyclic olefin polymer film and prevent thermal deterioration of the resin when heated to near Tg and processed, such as stretching.
The saturated water absorption at 23 ° C. of the cyclic olefin polymer is preferably 2% by weight or less, more preferably 0.01 to 2% by weight, and still more preferably 0.1 to 1% by weight. If the saturated water absorption is within this range, the optical characteristics are uniform, the resulting cyclic olefin polymer film is excellent in adhesiveness with other optical members and adhesives, and peeling occurs during use. In addition, it is excellent in compatibility with an antioxidant and the like, and can be added in a large amount. The saturated water absorption is a value obtained by immersing in 23 ° C. water for 1 week and measuring the increased weight according to ASTM D570.

The cyclic olefin polymer has a photoelastic coefficient (C _P ) of 0 to 100 (× 10 ⁻¹² Pa ⁻¹ ) and a stress optical coefficient (C _R ) of 1,500 to 4,000 (× Those satisfying 10 ⁻¹² Pa ⁻¹ ) are preferred. Here, with respect to the photoelastic coefficient (C _P ) and the stress optical coefficient (C _R ), various documents such as Polymer Journal, Vol. 27, No, 9pp 943-950 (1995), Journal of the Japanese Society of Rheology, Vol. .19, No. 2, p93-97 (1991), photoelastic experiment method, Nikkan Kogyo Shimbun, 7th edition of 1975. The former represents the degree of occurrence of phase difference due to stress in the glass state of the polymer, while the latter represents the degree of occurrence of phase difference due to stress in the flow state.
The large photoelastic coefficient (C _P ) is generated from an external factor or a strain generated from its own frozen strain when the cyclic olefin polymer film is used in combination with another optical member or an adhesive. Represents that the optical characteristics change sensitively due to stress, etc. For example, when a transparent conductive layer is laminated as in the present invention, and when used by being fixed to another optical member, the residual at the time of bonding It means that an unnecessary phase difference is likely to be generated due to a minute stress generated by distortion, shrinkage of a material due to temperature change, humidity change, and the like. Therefore, it is better that the photoelastic coefficient (C _P ) is as small as possible.
On the other hand, a large stress optical coefficient (C _R ) means that, for example, a desired retardation can be obtained with a small draw ratio when imparting the retardation to a cyclic olefin polymer film, or a large amount. There is a great merit that it is easy to obtain a film capable of imparting a phase difference, and when the same phase difference is desired, the film can be thinned as compared with a film having a small stress optical coefficient (C _R ).
From the above viewpoint, the photoelastic coefficient (C _P ) is preferably 0 to 100 (× 10 ⁻¹² Pa ⁻¹ ), more preferably 0 to 80 (× 10 ⁻¹² Pa ⁻¹ ), and still more preferably 0. To 50 (× 10 ⁻¹² Pa ⁻¹ ), particularly preferably 0 to 30 (× 10 ⁻¹² Pa ⁻¹ ), and most preferably 0 to 20 (× 10 ⁻¹² Pa ⁻¹ ). Minimizes unnecessary phase difference due to stress generated when the transparent conductive layer is laminated, stress generated when the conductive laminated film is fixed to other optical members, and phase change caused by environmental changes during use This is to limit it to the limit.

(Additive)
The cyclic olefin polymer can be further stabilized by adding known antioxidants, ultraviolet absorbers and the like. Moreover, in order to improve workability, the additive used in conventional resin processings, such as a lubricant, can also be added.
Examples of the antioxidant include pentaerythrityl tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] Examples of the ultraviolet absorber include 2,4-dihydroxybenzophenone and 2-hydroxy-4-methoxybenzophenone.

(Method for producing a film having a quarter-wave plate function)
The film having a quarter-wave plate function according to the present invention is obtained by molding the above cyclic olefin polymer into a film or a sheet by a known method such as a melt molding method or a solution casting method (solvent casting method). (Original fabric film) can be produced by stretching. As a method for forming the film, a solvent casting method is preferable from the viewpoint of good film thickness uniformity and surface smoothness. From the viewpoint of production cost, the melt molding method is preferable. The raw film has a film thickness of 70 to 250 μm, preferably 80 to 200 μm, and a difference between the maximum thickness and the minimum thickness of the film is within 3 μm, preferably within 2 μm.

  Specifically, the film having a quarter-wave plate function according to the present invention can be stretched by a known uniaxial stretching method or biaxial stretching method. That is, a horizontal uniaxial stretching method by a tenter method, a compression stretching method between rolls, a longitudinal uniaxial stretching method using rolls with different circumferences, a biaxial stretching method in which horizontal uniaxial and longitudinal uniaxial are combined, a stretching method by an inflation method Etc. can be used. Of these, longitudinal uniaxial stretching is preferred from the viewpoint of production cost.

  In the case of the uniaxial stretching method, the stretching speed is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably 100 to 1,000% / min, More preferably, it is 100 to 500% / min. In the case of the biaxial stretching method, stretching may be performed in two directions at the same time, or the stretching may be performed in a direction different from the first stretching direction after uniaxial stretching. In these cases, the intersection angle of the two stretching axes is usually in the range of 120 to 60 degrees. Further, the stretching speed may be the same or different in each stretching direction, and is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably. Is 100 to 1,000% / min, more preferably 100 to 500% / min.

The stretching temperature is not particularly limited, but is usually Tg ± 30 ° C., preferably Tg ± 10 ° C., more preferably Tg−5 to Tg + 10 ° C., based on the glass transition temperature (Tg) of the polymer. Range. Since it is within the above range, it is possible to suppress the occurrence of phase difference unevenness, and it is preferable because the refractive index ellipsoid can be easily controlled.
The draw ratio is usually 1.01 to 10 times, preferably 1.1 to 5 times, more preferably 1.1 to 3.5 times. When the draw ratio exceeds 10 times, it may be difficult to control the phase difference.
The stretched film may be cooled as it is, but it is allowed to stand in a temperature atmosphere of Tg-20 ° C. to Tg for at least 10 seconds, preferably 30 seconds to 60 minutes, more preferably 1 minute to 60 minutes. As a result, a film having a stable quarter-wave plate function with little change in retardation characteristics with time can be obtained.

Further, the linear expansion coefficient of the film having a quarter wavelength plate function is preferably 1 × 10 ⁻⁴ (1 / ° C.) or less, more preferably 9 × 10 ^{− in the} temperature range of 20 ° C. to 100 ° C. ⁵ (1 / ° C.) or less, more preferably 8 × 10 ⁻⁵ (1 / ° C.) or less, and particularly preferably 7 × 10 ⁻⁵ (1 / ° C.) or less. Further, the difference in linear expansion coefficient between the stretching direction and the direction perpendicular thereto is preferably 5 × 10 ⁻⁵ (1 / ° C.) or less, more preferably 3 × 10 ⁻⁵ (1 / ° C.) or less, and further preferably 1 × 10 ⁻⁵ (1 / ° C.) or less. By setting the coefficient of linear expansion within the above range, when the film having the ¼ wavelength plate function is used in the conductive laminated film of the present invention, a stress change caused by temperature, humidity, etc. during use is caused. It is possible to suppress a change in retardation and a change in resistance value of the transparent conductive film, and to obtain long-term stability when used as the conductive laminated film of the present invention.

The film stretched as described above is oriented with molecules due to stretching and gives a phase difference to transmitted light. This phase difference is the retardation value of the film before stretching, the stretching ratio, the stretching temperature, the stretching orientation. It can be controlled by the thickness of the later film.
The total light transmittance of the film having a ¼ wavelength plate function is preferably 85% or more, more preferably 88% or more, and still more preferably 90% or more because the visibility of the touch panel is improved.
Moreover, since the thickness of the film which has a 1/4 wavelength plate function ensures favorable handling and winding up to a roll shape becomes easy, it is 1-500 micrometers normally, Preferably it is 1-300 micrometers. Preferably it is 10-250 micrometers, More preferably, it is 50-200 micrometers.
The thickness distribution of a film having a 1/4 wavelength plate function is usually within ± 20%, preferably within ± 10%, more preferably within ± 5%, and even more preferably within ± 3% with respect to the average value. . The variation in thickness per 1 cm is usually 10% or less, preferably 5% or less, more preferably 1% or less, and further preferably 0.5% or less. By performing such thickness control, unevenness in the surface of the conductive laminated film can be prevented.

Moreover, the film which has a 1/4 wavelength plate function based on this invention may give the surface treatment in order to improve adhesiveness with a particle | grain containing resin layer. Examples of the surface treatment include plasma treatment, corona treatment, alkali treatment, and coating treatment. In particular, by using corona treatment, the adhesion between the film having a quarter-wave plate function and the particle-containing resin layer can be strengthened.
The corona treatment condition is preferably 1~1000W / m ² / min as an irradiation amount of corona discharge electron, and more preferably to 10~100W / m ² / min. If the irradiation dose is lower than this, a sufficient surface modification effect may not be obtained, and if the irradiation dose is higher than this, the treatment effect is achieved even inside the film having a quarter-wave plate function. However, the film itself may be deteriorated. This corona treatment may be performed not only on the surface in contact with the particle-containing resin layer but also on the opposite surface.
Moreover, it may be applied immediately after the corona treatment or may be applied after neutralization. However, since the appearance of the particle-containing resin layer is improved, it is preferable to perform the application after neutralization.

<Particle-containing resin layer>
The particle-containing resin layer is formed on at least one surface of a film having a quarter-wave plate function and protects the film having a quarter-wave plate function from being damaged, and the conductive laminated film surface or It has an antiglare action against reflected light at the film interface having a quarter-wave plate function.
The particle-containing resin layer is usually composed of particles for exhibiting antiglare properties and a binder. The binder is preferably formed from an active energy ray-curable resin composition.
The particle-containing resin layer is formed by coating and drying a coating composition in a slurry form by dispersing or dissolving particles and an active energy ray-curable resin in an organic solvent in which these particles can be dispersed or dissolved. , A layer formed by curing the resin.

(particle)
The particles used in the particle-containing resin layer are not particularly limited. For example, any of those usually used as a filler may be used, such as an acrylic resin, an aromatic vinyl resin, carbon black, copper, nickel, silver, Iron or composite powder thereof; zinc oxide, tin oxide, titanium oxide, tin monoxide, calcium oxide, magnesium oxide, beryllium oxide, aluminum oxide, silica (fumed silica, fused silica, precipitated silica, ultrafine powder amorphous silica Metal oxides such as calcium carbonate, potassium carbonate, sodium carbonate, magnesium carbonate, barium carbonate; metal nitrides such as boron nitride, silicon nitride, aluminum nitride, SiC, etc. Metal carbides; metal hydroxides such as aluminum hydroxide and magnesium hydroxide; boric acid Aluminum, barium titanate, calcium phosphate, calcium silicate, clay, gypsum, barium sulfate, mica, diatomaceous earth, white clay, talc, zeolites, pigments, and the like. Of these, acrylic resins, aromatic vinyl resins, and silica are preferable from the viewpoint of production cost.

  The number average particle diameter of the particles used for forming the particle-containing resin layer is not particularly limited, and is, for example, 0.8 to 10 μm, preferably 0.9 to 7 μm, more preferably 1 to 5 μm. . By having such an average particle diameter, the transparency of the resin composition can be secured and the haze value can be adjusted to an appropriate value. Thereby, there is no luminance unevenness and a conductive laminated film with good antiglare property is obtained. Two or more kinds of particles having different particle diameters may be used.

  In addition, it is preferable to use irregular polymer particles having a shape in which two or more substantially spherical particles are bonded together because the anti-Newton ring property is improved. The deformed polymer particles are preferably polymer particles containing a styrene resin, an acrylic resin or the like, and are formed into a shape in which two or more particles are combined by seed polymerization using one substantially spherical particle as a seed polymer particle. It is preferable.

(Active energy ray-curable resin composition)
The binder of the particle-containing resin layer is preferably formed from an active energy ray-curable resin composition. The active energy ray-curable resin composition preferably comprises (A) a polyfunctional monomer having three or more acryloyl groups (hereinafter also referred to as “component (A)”), (B) glycidyl (meth) acrylate polymer and acrylic. A polymer obtained by addition reaction of an acid (hereinafter also referred to as “component (B)”) and (C) optionally other acrylic oligomer (hereinafter also referred to as “component (C)”) in a specific amount. . In particular, the component (A) is a component that can impart the hardness of the transparent conductive layer followed by the active energy ray-curable resin composition, the adhesion to the transparent resin film, and the like. The component (B) is a component that can impart further improvement in the hardness of the transparent conductive layer, curability, reduction of curling during curing, and the like. By blending the component (B), the component (B) has a high molecular weight and has many hydroxyl groups in the molecule, so the compatibility with the highly hydrophobic component (A) decreases. (B) It is thought that it is because it transfers to the surface of the surface protective film from which a component is obtained. (C) component is an arbitrary component which can provide toughness etc.

The surface tension of the component (A) is suitably in the range of 37 mN / m or less, more preferably 30 mN / m or more, from the viewpoint that sufficient hardness and adhesion can be obtained. The surface tension is measured by a vertical plate method (wilhemy method) using a Kyowa CBVP surface tension meter.
Specific examples of the component (A) include trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, triacrylate of glycerol propylene glycol adduct, and triacrylate of trimethylolpropane propylene glycol adduct. Trimethylolpropane triacrylate and ditrimethylolpropane tetraacrylate are preferable because the cured coating film has high hardness.
The blending amount of the component (A) in the active energy ray-curable resin composition is suitably 40 to 60% by weight (however, the total of the components (A) to (C) is 100% by weight). And is preferably 50 to 60% by weight.

  As described above, the component (B) is a polymer acrylate obtained by addition reaction of acrylic acid to a glycidyl (meth) acrylate polymer. The addition amount of acrylic acid to the epoxy group is suitably about 1: 1 to 1: 0.8 because unreacted epoxy adversely affects the stability of the composition, and 1: 1 to 1: 0.9. The degree is preferred.

  Examples of the glycidyl (meth) acrylate polymer include homopolymers of glycidyl (meth) acrylate, copolymers of glycidyl (meth) acrylate and various α, β-unsaturated monomers not containing a carboxyl group, and the like. Can be mentioned. Examples of the α, β-unsaturated monomer not containing the carboxyl group include various (meth) acrylic acid esters, styrene, vinyl acetate, acrylonitrile and the like. When glycidyl (meth) acrylate and an α, β-unsaturated monomer not containing a carboxyl group are copolymerized to obtain a glycidyl (meth) acrylate polymer, crosslinking occurs during the reaction. Therefore, high viscosity and gelation can be effectively prevented. The molecular weight of the glycidyl (meth) acrylate polymer is a weight average molecular weight of about 5,000 to 100,000 from the viewpoint of curling reduction during curing and prevention of gelation during the acrylic addition reaction, and 10,000 to 50 About 1,000 is preferable. (B) 70 weight% or more is suitable for the usage-amount of the glycidyl (meth) acrylate in a component in consideration of the hardness of a transparent conductive layer, the transferability of a polymer, etc., and 75 weight% or more is preferable.

A known copolymerization method can be applied to the production of the component (B). The glycidyl (meth) acrylate polymer is produced by charging this monomer, a polymerization initiator, and, if necessary, a chain transfer agent and a solvent into a reaction vessel, under conditions of 80 to 90 ° C. for about 3 to 6 hours under a nitrogen stream. It is appropriate to do in The resulting glycidyl (meth) acrylate polymer and acrylic acid can be subjected to a ring-opening esterification reaction to obtain the component (B). Usually, in order to prevent polymerization of acrylic acid itself, The reaction temperature is suitably 100 to 120 ° C., and the reaction time is suitably about 5 to 8 hours.
The blending amount of the component (B) in the active energy ray-curable resin composition is suitably 10 to 60% by weight (however, the total of the components (A) to (C) is 100% by weight). 20 to 50% by weight is preferable.

Specific examples of the component (C) include polyfunctional polyester acrylate, polyfunctional urethane acrylate, and epoxy acrylate. Of these, polyfunctional urethane acrylates are preferred from the viewpoints of scratch resistance and toughness of the cured coating film. For example, (a) a urethane reaction product of (meth) acrylate having a hydroxyl group and an isocyanate compound having two or more isocyanate groups in the molecule, and (b) an isocyanate compound having two or more isocyanate groups in the molecule. Examples include a reaction product obtained by reacting a polyol, polyester or polyamide-based diol to synthesize an adduct and then adding a (meth) acrylate having a hydroxyl group to the remaining isocyanate group (for example, JP-A-2002-275392). Issue).
The polyfunctional urethane acrylate is a urethane reaction product composed of a (meth) acrylate having a hydroxyl group and a polyvalent isocyanate compound having two or more isocyanate groups. As the (meth) acrylate having a hydroxyl group, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate and the like are preferable.
The blending amount of the component (C) in the active energy ray-curable resin composition is suitably 0 to 50% by weight (however, the total of the components (A) to (C) is 100% by weight).

  The active energy ray-curable resin composition can be blended with an organic solvent in order to adjust the viscosity according to the individual application. As the organic solvent, those which do not dissolve the cyclic olefin polymer film, which is a transparent film, are suitable. For example, ester solvents, alcohol solvents, and ketone solvents are preferable.

  As the active energy ray used for curing the active energy ray-curable resin composition, for example, any of ultraviolet rays, electron beams and the like may be used. When the resin composition is cured with an electron beam or the like, a photopolymerization initiator is not required, but when cured with ultraviolet rays, the photopolymerization initiator is usually 1 to 15 weights per 100 parts by weight of the resin composition. About parts can be contained. As the photopolymerization initiator, various known ones such as Darocur 1173, Irgacure 651, Irgacure 184, Irgacure 907, Irgacure 754 (all manufactured by Ciba Specialty Chemicals) and benzophenone can be used. If necessary, various additives other than those described above, for example, a polymerization inhibitor, an antioxidant, an ultraviolet absorber, an antistatic agent, a light stabilizer, a solvent, an antifoaming agent, and a leveling agent may be blended.

(Other ingredients)
In addition to the particles and the active energy ray-curable resin composition, the coating composition may contain other components such as a curing agent, a dispersing agent, and a dye as necessary.
The content of other components is preferably 0 to 10 parts by weight, more preferably 0 to 5 parts by weight, based on 100 parts by weight of the particle + active energy ray-curable resin composition. It is especially preferable that it is -3 weight part.

(Organic solvent)
The organic solvent contained in the coating composition only needs to disperse or dissolve the particles and the active energy ray-curable resin composition to form the coating composition in a slurry state. Examples include water, toluene, cyclohexane, methyl isobutyl ketone (MIBK), methyl ethyl ketone (MEK), N-methyl-2-pyrrolidone (NMP), and the like.
The content ratio of the organic solvent with respect to the coating composition is preferably 10 to 2000 parts by weight, more preferably 20 to 1000 parts by weight with respect to 100 parts by weight of the particles + active energy ray curable resin composition. preferable.

(Manufacturing method of coating composition)
A coating composition can be obtained by uniformly dispersing or dissolving the particles and the active energy ray-curable resin composition and the above-described other components added as necessary. Other components may be dispersed or dissolved later. Although it does not specifically limit about the stirring method, For example, it can stir using various kneaders, a bead mill, a high-pressure homogenizer, etc.

(Method for forming particle-containing resin layer)
The particle-containing resin layer is formed by coating and drying the above-mentioned coating composition dispersed or dissolved in particles, active energy ray-curable resin, and an organic solvent in which these particles can be dispersed or dissolved with various coaters. The resin is cured.
The particles are preferably contained in the particle-containing resin layer in an amount of 0.5 to 50% by weight, more preferably 0.5 to 10% by weight, and still more preferably 1 to 5% by weight. It is suitable from a viewpoint of anti-glare property that the content rate of particle | grains is in the said range.
The coating method of the particle-containing resin layer includes bar coater coating, air knife coating, gravure coating, gravure reverse coating, reverse roll coating, lip coating, die coating, dip coating, offset printing, flexographic printing Various methods such as printing and screen printing can be employed. Gravure reverse coating or die coating is preferable because the appearance of the particle-containing resin layer is improved.

The particles contained in the particle-containing resin layer are integrated on a film having a quarter-wave plate function by a cured resin. Note that some of the particles may be in a state in which some of the particles protrude from the surface of the resin. Further, the protruding portion of the particles may be entirely covered with the resin, or only a part thereof may be covered. Note that all of the particles may be completely buried in the resin.
Although it does not specifically limit about the thickness of a particle-containing resin layer, Usually, 1-20 micrometers, Preferably it is about 1-7 micrometers.

(Physical properties of laminated film comprising a film having a 1/4 wavelength plate function / particle-containing resin layer)
(1) Haze is also called haze value and represents the degree of cloudiness and the degree of diffusion. For example, using a commercially available Suga Test Instruments Co., Ltd. HGM-2DP, etc., it conforms to JIS K-7136. The haze (%) can be measured. The haze of the title film is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less. When the haze is outside the above range, white blur occurs and the visibility of the touch panel decreases.
(2) When the total light transmittance (%) is measured according to JIS K-7361 using, for example, a commercially available Suga Test Instruments Co., Ltd. HGM-2DP, the visibility of the touch panel is improved. Therefore, 80% or more is preferable, 83% or more is more preferable, and 85% or more is more preferable.

(3) When the transmitted light b * is measured according to JIS Z-8722 using, for example, a commercially available color difference meter RETS-1200VA manufactured by Otsuka Electronics Co., Ltd., the visibility of the touch panel is improved. Therefore, 0 to 10 is preferable, 0 to 5 is more preferable, and 0 to 2 is more preferable.
(4) Pencil hardness is preferably HB or higher when measured according to JIS K5600-5-4 using NP manufactured by Toyo Seiki Co., Ltd. If it is less than HB, the transparent conductive film may be damaged during ITO film formation.

(5) For anti-glare properties, when a fluorescent lamp (total luminous flux 3520 lm) is projected on the title film and the degree of blur of the fluorescent lamp outline is visually evaluated, it is preferable that the outline of the fluorescent lamp is not known at all.
(6) It is preferable that the luminance unevenness of the pixel is hardly recognized when the screen of the mobile tool SL-6000N manufactured by Sharp is displayed in green and then evaluated by visual observation after placing the title film thereon.

(7) Anti-Newton ring property is whether the Newton ring is generated by placing the title film on a smooth glass plate (thickness 3 mm, material: soda glass) so that the particle-containing resin layer is in close contact with the finger and pressing it with a finger. When visually evaluating, it is preferable that Newton rings do not occur.
(8) The heat shrinkage rate (%) is determined by allowing the title film to stand for 60 minutes in a forced circulation dryer heated to 150 ° C., and using a dimension measurement microscope 176-812 made by Mitutoyo before and after heating. When measuring the change and calculating the heat shrinkage rate, it is preferably 1.5% or less, more preferably 1.3% or less, and even more preferably 1.0% or less. If the heat shrinkage rate exceeds 1.5%, the touch panel may be deformed.

(9) For the residual solvent (%), the title film was allowed to stand for 30 minutes in a forced circulation dryer heated to 160 ° C., the mass change before and after heating was examined, and the mass increase rate (%) was determined as the residual solvent (%). %) Is preferably 2% or less, more preferably 1.5% or less, and even more preferably 1% or less. If the residual solvent exceeds 2%, the amount of the volatile solvent at the time of ITO film formation increases and a defect of the ITO film may occur.
(10) The phase difference is preferably 128 to 148 nm, preferably 133 to 143 nm when measuring the phase difference (nm) with respect to light having a wavelength of 550 nm using “KOBRA-21ADH / PR” manufactured by Oji Scientific Instruments. Is more preferable. When the phase difference deviates from the above, the contrast and visibility of the liquid crystal display are lowered.

<Transparent conductive layer>
The conductive laminated film of the present invention is obtained by further laminating a transparent conductive layer on a film obtained by laminating a particle-containing resin layer on the surface of the above-described film having a ¼ wavelength plate function.
The transparent conductive layer has a weight ratio of indium oxide to tin oxide of 95: 5 to 99: 1, and further contains polythiophene, inorganic nanoparticles, metal elements, etc. within a range not impairing the effects of the present application. It may be a layer having transparency in the visible light region and having conductivity.

A conventionally well-known ITO target is used as a target at the time of forming a transparent conductive film. As a target agent used for forming the ITO film, the weight ratio of indium oxide to tin oxide is preferably 95: 5 to 99: 1, more preferably 96: 4 to 98: 2, and still more preferably 97: 3 to 98: It is desirable to use two. When the weight ratio is out of the above range, the resistance value increases. Further, when the weight ratio is within the above range, when combined with a film having a quarter-wave plate function composed of a cyclic olefin polymer having a structure derived from the formula (1), and a particle-containing resin layer, Reflective reflection does not occur, the contrast is high, the change in retardation after heat treatment is small, and a conductive laminated film excellent in durability can be obtained.
The substrate temperature during ITO film formation is preferably “room temperature to film Tg”, more preferably “room temperature to film Tg−20 ° C.”. If it is Tg or more, film deterioration may occur.
Further, Ar is a trace amount of oxygen as an atmospheric gas during film formation, preferably 0.05 to 20% by volume, more preferably 0.01 to 10% by volume, and still more preferably based on the total of Ar and O _2. When 0.1 to 3% by volume of O ₂ is introduced, the transparency and conductivity of the ITO thin film can be improved.

  As a method for forming the transparent conductive layer, any of the conventionally known techniques such as a vacuum deposition method, a sputtering method, and an ion plating method can be used, but the uniformity of the film and the adhesion of the thin film to the transparent substrate can be used. From the viewpoint, thin film formation by sputtering is preferable. In addition to the above, the thin film material to be used is, for example, metal oxide such as tin oxide containing antimony, gold, silver, platinum, palladium, copper, aluminum, nickel, chromium, titanium, cobalt, tin, or these An alloy or the like may be used. The thickness of the conductive thin film is preferably 30 mm or more, and if it is thinner than this, it may be difficult to form a continuous film having good conductivity with a surface resistance of 1000 Ω / □ or less. On the other hand, if it is too thick, it may cause a decrease in transparency and the like, and a suitable thickness is about 50 to 2000 mm.

<Easily adhesive layer>
While improving the adhesiveness between the particle-containing resin layer and the transparent conductive layer, an easy-adhesion layer may be laminated for the purpose of providing gas barrier properties. The easy-adhesion layer may or may not contain metal oxide fine particles, but it is preferable to contain metal oxide fine particles because adhesion is improved. Usually, a preferable easy-adhesion layer is obtained by preparing a coating liquid composed of a composition containing metal oxide fine particles and polysiloxane, and coating and drying the coating liquid on a transparent resin film.

(Metal oxide fine particles)
The type of metal oxide fine particles used in the easy adhesion layer is not particularly limited as long as it is an oxide fine particle of a metal element. For example, antimony oxide, zirconium oxide, anatase type titanium oxide, rutile type titanium oxide, brookite type oxidation Titanium, zinc oxide, tantalum oxide, indium oxide, hafnium oxide, tin oxide, niobium oxide, aluminum oxide, cerium oxide, scandium oxide, yttrium oxide, lanthanum oxide, praseodymium oxide, neodymium oxide, samarium oxide, europium oxide, gadolinium oxide, Terbium oxide, dysprosium oxide, holmium oxide, erbium oxide, thulium oxide, ytterbium oxide, lutetium oxide, calcium oxide, gallium oxide, lithium oxide, strontium oxide, tungsten oxide, oxide Potassium, magnesium oxide, and complexes thereof, and indium - such as oxides of the metal 2 or more complex such as tin composite oxides.
The primary average particle diameter of the metal oxide fine particles is preferably 0.1 to 100 nm, more preferably 0.1 to 70 nm, and particularly preferably 0.1 to 50 nm. When the primary average particle diameter of the metal oxide fine particles is in the above range, a laminated film having excellent light transmittance can be obtained.

(Polysiloxane)
The polysiloxane used for the easy-adhesion layer is preferably a polyfunctional polysiloxane.
As the polyfunctional polysiloxane, a polysiloxane obtained by subjecting a polyfunctional polysiloxane having a dimethylsiloxane chain and a polydimethylsiloxane to a dealcoholization reaction is preferable. The polyfunctional polysiloxane and the polydimethylsiloxane preferably have an alkoxyl group or a hydroxyl group at the terminal functional group. The polyfunctional polysiloxane and the polydimethylsiloxane are obtained by subjecting dimethylsiloxane and polydimethylsiloxane having different terminal functional groups to a dealcoholization reaction. Polysiloxane is obtained.

<Antireflection layer>
The conductive laminated film of the present invention preferably has an antireflection layer between the transparent conductive layer and the particle-containing resin layer for the purpose of improving the transmittance in the visible light region. The antireflection layer usually has a laminated structure of two or more layers including a low refractive index layer such as silicon oxide and magnesium fluoride and a high refractive index layer such as titanium oxide, niobium oxide and tantalum oxide.
As a method for forming a low and high refractive index layer composed of these inorganic oxides, vacuum deposition, sputtering, ion plating (dry process) or ultrafine particles of inorganic oxides such as metal alkoxides and zirconium oxide are used. A publicly known method such as a coating method (wet process) of the coating liquid containing it can be employed.
It is also preferable to apply an organic material mainly composed of a fluoropolymer as the low refractive layer.

<Conductive laminated film>
As preferred embodiments of the conductive laminated film of the present invention, the following <1> to <3> may be mentioned.
<1> A surface on which a particle-containing resin layer and a transparent conductive layer are sequentially laminated on a film surface having a 1/4 wavelength plate function, and the particle-containing resin layer of the film having a 1/4 wavelength plate function is formed; Is a conductive laminated film in which a particle-containing resin layer is further laminated on the opposite surface.
That is, it is a conductive laminated film laminated in the order of transparent conductive layer / particle-containing resin layer / film having a 1/4 wavelength plate function / particle-containing resin layer.
<2> a surface on which a particle-containing resin layer and a transparent conductive layer are sequentially laminated on a film surface having a quarter-wave plate function, and the particle-containing resin layer of the film having a quarter-wave plate function is formed; Is a conductive laminated film in which a hard coat layer is further laminated on the opposite surface.
That is, it is a conductive laminated film laminated in the order of transparent conductive layer / particle-containing resin layer / film having a 1/4 wavelength plate function / hard coat layer.
<3> A hard coat layer and a transparent conductive layer are sequentially laminated on the surface of the transparent resin film, and particles are further formed on the surface opposite to the surface on which the hard coat layer of the film having the 1/4 wavelength plate function is formed. A conductive laminated film in which a containing resin layer is laminated.
That is, it is an electroconductive laminated film laminated in the order of transparent electroconductive layer / hard coat layer / film having a 1/4 wavelength plate function / particle-containing resin layer.

The conductive laminated film is a coating composition containing no particles on the surface opposite to the surface on which the particle-containing resin layer of the film having a 1/4 wavelength plate function is formed (hereinafter also referred to as “hard coat treatment agent”). .) That is, it is preferable that a hard coat layer made of an active energy ray-curable resin composition is formed. In this case, the film thickness of a hard-coat layer is not specifically limited, The film thickness similar to the particle-containing resin layer mentioned above is mentioned. Thus, by providing a resin layer on both surfaces, warping of the film can be prevented.
Moreover, it is preferable that an electroconductive laminated film laminate | stacks an antireflection layer between a transparent conductive layer and a particle-containing resin layer, or between a transparent conductive layer and a hard-coat layer. Providing the antireflection layer in this manner is preferable because the transmittance in the visible light region is further improved.

A preferable aspect is shown below about each physical property measured according to the method mentioned above of an electroconductive laminated film.
(1) The haze is preferably about 5 to 12%, more preferably about 5 to 10%. When the haze is within the above range, white blur can be prevented and the background image can be projected more clearly. The haze correlates with the average particle diameter, particle size distribution, content ratio, and the like of the deformed polymer particles contained in the particle-containing resin layer and the conductive particles contained in the transparent conductive layer.
(2) The total light transmittance is preferably 80% or more, more preferably 83% or more, and even more preferably 85% or more because the visibility of the touch panel is improved.

(3) The transmitted light b * is preferably 0 to 12, more preferably 0 to 7, and still more preferably 0 to 4, since the visibility of the touch panel is improved.
(4) The pencil hardness is preferably HB or higher. If the pencil hardness is less than HB, the transparent conductive film may be damaged during ITO film formation.
(5) It is preferable that the antiglare property does not reveal the outline of the fluorescent lamp.

(6) It is preferable that the luminance unevenness hardly recognizes the luminance unevenness of the pixel.
(7) It is preferable that anti-Newton ring property does not generate Newton ring.
(8) The heat shrinkage rate is preferably 1.5% or less, more preferably 1.3% or less, and further preferably 1.0% or less. If the heat shrinkage rate exceeds 1.5%, the touch panel may be deformed.

(9) The residual solvent is preferably 2% or less, and more preferably 1% or less.
(10) The phase difference is preferably 128 to 148 nm, preferably 133 to 143 nm when measuring the phase difference (nm) with respect to light having a wavelength of 550 nm using “KOBRA-21ADH / PR” manufactured by Oji Scientific Instruments. Is more preferable. When the phase difference deviates from the above, the contrast and visibility of the liquid crystal display are lowered. Moreover, it is preferable that the change of the phase difference before and after heat-processing a conductive laminated film at 150 degreeC for 2 hours is 7% or less, Preferably it is 5% or less.
(11) The surface resistance (Ω / □) is preferably 200 to 1500Ω / □, for example, when measured using a commercially available low resistivity meter “Loresta-GP” manufactured by Mitsubishi Chemical Corporation. -1000Ω / □ is more preferable, and 300-500Ω / □ is more preferable. If the surface resistance exceeds 1500 Ω / □, it may be difficult to form a continuous film having good conductivity. On the other hand, if it is less than 200 Ω / □, transparency may be lowered and a touch panel may malfunction.

<Polarizing plate>
The polarizing plate of the present invention is characterized in that the above-mentioned conductive laminated film of the present invention is laminated on a polarizing film. Examples of such a polarizing plate include those in which a conductive laminated film is formed on one side of a polarizing film.
The polarizing film is not particularly limited, but functions as a polarizing film, that is, incident light is divided into two polarization components orthogonal to each other, only one of them is allowed to pass, and the other component is absorbed or dispersed. The polarizing film is not particularly limited as long as it has a function of allowing the dichroic dye to adsorb on the PVA film, for example, polyvinyl alcohol (hereinafter also referred to as “PVA”) / iodine polarizing film. Oriented PVA / dye polarizing film; polyene polarizing film in which polyene is formed by dehydration reaction of PVA film, dehydrochlorination reaction of polyvinyl chloride film, etc .; from modified PVA containing cationic groups in the molecule And a polarizing film having a dichroic dye on the surface and / or inside of the PVA-based film. Of these, PVA / iodine polarizing films are preferred.

The manufacturing method of a polarizing film is not specifically limited, A conventionally well-known method is applicable. For example, a method of adsorbing iodine ions after stretching a PVA-based film; a method of stretching a PVA-based film after dyeing with a dichroic dye; a method of stretching a PVA-based film and then dyeing with a dichroic dye; And a method of stretching a chromogenic dye on a PVA-based film; a method of stretching a PVA-based film and then printing a dichroic dye. More specifically, iodine is dissolved in a potassium iodide solution to form higher-order iodine ions, the ions are adsorbed on a PVA film and stretched, and then a 1 to 5% by weight boric acid aqueous solution has a bath temperature of 30. A method for producing a polarizing film by immersing at -40 ° C; or a PVA film treated with boric acid in the same manner as described above and stretched about 3 to 7 times in a uniaxial direction, and then 0.05 to 5 wt% dichroism Examples include a method for producing a polarizing film by immersing the dye in an aqueous dye solution at a bath temperature of 30 to 40 ° C. to adsorb the dye, then drying at 80 to 100 ° C. and heat setting.
Although the thickness of a polarizing film is not specifically limited, 10-50 micrometers is preferable and 15-45 micrometers is more preferable.
These polarizing films may be used as they are for the production of the polarizing plate of the present invention, but can also be used after the corona discharge treatment or plasma treatment is applied to the surface in contact with the adhesive layer.

The polarizing plate of the present invention is bonded to the polarizing film with a pressure sensitive adhesive on the surface opposite to the transparent conductive layer of the conductive laminated film in which the cyclic olefin polymer film, the particle-containing resin layer and the transparent conductive layer are laminated. It is preferable to constitute a polarizing plate.
As the pressure sensitive adhesive, a polyvinyl alcohol pressure sensitive adhesive, an acrylic pressure sensitive adhesive, a rubber pressure sensitive adhesive, a silicone pressure sensitive adhesive, and the like are suitable.
The polarizing plate of the present invention can be suitably used as a transparent electrode for a display such as a liquid crystal display or a touch panel described later, and is particularly suitable for a touch panel application, particularly a touch panel application for a display device.

<Touch panel>
The touch panel of the present invention is characterized in that a transparent conductive layer and a polarizing plate are integrated, and is called a so-called polarizing plate integrated inner touch panel. Specifically, the polarizing plate of the present invention is suitably used as an upper electrode and / or a lower electrode of a touch panel such as a 4-wire resistive film system or a 5-wire resistive film system. And the display apparatus which has a touch-panel function is obtained by arrange | positioning this touch panel in the front surface of a liquid crystal display.

EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples. Hereinafter, “part” means “part by weight”.
Various physical properties were measured or evaluated as follows.
(1) Haze Using a Suga Test Instruments Co., Ltd. HGM-2DP, haze (%) was measured based on JIS K-7136.
(2) Total light transmittance Total light transmittance (%) was measured based on JIS K-7361 using Suga Test Instruments Co., Ltd. HGM-2DP.

(3) Transmitted light b *
Using a color difference meter RETS-1200VA manufactured by Otsuka Electronics Co., Ltd., the transmitted light b * was measured according to JIS Z-8722.
(4) Pencil hardness Pencil hardness was measured based on JIS K-5600-5-4 using a pencil scratch coating film hardness tester NP manufactured by Toyo Seiki Co., Ltd.
(5) Antiglare property A fluorescent lamp (total light flux: 3520 lm) was projected on the film, and the degree of blurring of the outline of the fluorescent lamp was visually evaluated according to the following criteria.
○: The outline of the fluorescent lamp is not known at all.
Δ: The outline of the fluorescent lamp is slightly understood.
X: The outline of the fluorescent lamp can be clearly seen.

(6) Luminance unevenness The screen of the mobile tool SL-6000N manufactured by Sharp was displayed in green, and then a film was placed thereon, and visually evaluated according to the following criteria.
○: Pixel luminance unevenness is hardly recognized.
Δ: Pixel luminance unevenness can be recognized but is not noticeable.
X: Pixel brightness unevenness can be clearly recognized.

(7) Anti-Newton ring property The film is placed on a smooth glass plate (thickness 3 mm, material: soda glass) so that the particle-containing resin layer is in close contact, and pressed with a finger to see if Newton rings occur. evaluated.
○: Newton ring does not occur.
Δ: Newton ring slightly occurs.
X: Newton ring clearly occurs.

(8) Heat shrinkage rate The film was allowed to stand for 60 minutes in a forced circulation dryer heated to 150 ° C., and the dimensional change of the film before and after heating was measured using a dimension measurement microscope 176-812 made by Mitutoyo. The direction (MD) and the width direction (TD) were measured, respectively, and the heat shrinkage rate (%) was calculated.
(9) Residual solvent The film was allowed to stand in a forced circulation dryer heated to 160 ° C. for 30 minutes, the mass change before and after heating was examined, and the mass increase rate (%) was defined as the residual solvent (%).
(10) The phase difference (nm) at a wavelength of 550 nm of the transparent conductive laminated film before and after the treatment at 150 ° C. for 2 hours was measured using “KOBRA-21ADH / PR” manufactured by Oji Scientific Instruments.
(11) Surface resistance The surface resistance value (Ω / □) of the transparent conductive layer was measured using a low resistivity meter “Loresta-GP” manufactured by Mitsubishi Chemical Corporation.

(12) Contrast evaluation of touch panel In the dark room, the black display screen of the touch panel was viewed from the front, and the color change was visually observed and evaluated according to the following criteria.
○: No change in touch panel color.
Δ: Some change in the color of the touch panel is observed.
X: The color change of a touch panel is large.

(13) Visibility evaluation of touch panel The color change of the screen when the viewing angle was changed was visually observed.
○: No change in touch panel color.
Δ: Some change in the color of the touch panel is observed.
X: The color change of a touch panel is large.

[Synthesis Example] Cyclic Olefin Polymer A
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . ^1,7,10 ] -3-dodecene 227.5 parts, bicyclo [2.2.1] hept-2-ene 22.5 parts, 1-hexene (molecular weight regulator) 18 parts, toluene (for ring-opening polymerization reaction) (Solvent) 750 parts were charged into a nitrogen-substituted reaction vessel, and this solution was heated to 60 ° C. Next, 0.62 part of a toluene solution of triethylaluminum (1.5 mol / L) and tungsten hexachloride modified with t-butanol / methanol (t-butanol: methanol: tungsten) were added to the solution in the reaction vessel. 37 parts of a toluene solution (concentration 0.05 mol / L) of 35 mol: 0.3 mol: 1 mol) was added, and this system was heated and stirred at 80 ° C. for 3 hours to cause ring-opening polymerization reaction. Thus, a ring-opening copolymer solution was obtained. The polymerization conversion rate in this polymerization reaction was 97%.
The autoclave was charged with 4,000 parts of the ring-opening copolymer solution thus obtained, and 0.48 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening copolymer solution. And a hydrogenation reaction was performed by heating and stirring for 3 hours under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 160 ° C.
After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a coagulated product, which was dried to obtain a hydrogenated cyclic olefin polymer A.

[Production Example 1] Cyclic olefin polymer film A-1
The cyclic olefin polymer A obtained in the synthesis example was dissolved in toluene so that the solid content concentration was 30%. The solution viscosity at room temperature of the obtained solution was 30,000 mPa · s. In this solution, pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added in an amount of 0.1 weight with respect to 100 parts by weight of the cyclic olefin polymer A. The resulting solution was filtered using a metal fiber sintered filter made by Nippon Pole with a pore diameter of 5 μm while controlling the flow rate of the solution so that the differential pressure was within 0.4 MPa. Using an “INVEX Lab Coater” manufactured by Inoue Metal Industry installed in a clean room, a PET film having a thickness of 100 μm (made by Toray Industries, Inc.) treated with an acrylic acid-based surface treatment agent to make it hydrophilic (easy to adhere). Lumirror U94 "). Next, the obtained liquid layer was subjected to a primary drying treatment at 50 ° C., and further subjected to a secondary drying treatment at 90 ° C., and then peeled off from the PET film, whereby a 188 μm-thick cyclic olefin-based weight was obtained. Combined film A-1 was formed. The obtained cyclic olefin polymer film A-1 had a residual solvent amount of 0.5% by weight and a light transmittance of 93% or more.

[Production Example 2] Cyclic olefin polymer film A-2
Film A-1 obtained in Production Example 1 was heated to 148 ° C. in a longitudinal stretching furnace provided with a wind direction control plate, and the temperature distribution in the stretching machine furnace was controlled within 148 ± 0.2 ° C. In the furnace at a speed of 4.0 m / min and 1.2 times in the film longitudinal direction, uniaxial stretching without fixing the film width direction, R0 is 138 nm, R0 variation is ± 5 nm, and the optical axis is the film longitudinal direction 0-2 degree cyclic olefin polymer film A-2 was obtained.

[Production Example 3] Polarizing film Pre-stretching of PVA at a stretching ratio of 3 in a dyeing bath at a temperature of 30 ° C consisting of an aqueous solution having an iodine concentration of 0.03% by weight and a potassium iodide concentration of 0.5% by weight. Processed, followed by post-stretching at a draw ratio of 2 in a crosslinking bath consisting of an aqueous solution having a boric acid concentration of 5% by weight and a potassium iodide concentration of 8% by weight, followed by drying treatment Thus, a polarizing film was obtained.

[Preparation Example 1] Mixed adhesive PWA resin 163-030545 (molecular weight: 22,000, degree of saponification: 88 mol%) manufactured by Wako Pure Chemical Industries, Ltd. is added with water to obtain a solid content concentration. A 7 wt% aqueous solution was prepared. On the other hand, 100 parts of WLS-201 (solid concentration 35% by weight) manufactured by Dainippon Ink and Chemicals, which is a polyurethane resin, is added to CR- manufactured by Dainippon Ink & Co., which is a polyepoxy curing agent. 5 L (100% active ingredient product) 5 parts was blended and diluted with water to prepare an aqueous solution with a solid content of 20% by weight. The obtained polyurethane resin aqueous solution and polyvinyl alcohol resin aqueous solution were mixed at a weight ratio of 1: 1 (solid content weight ratio of 80:20), and a mixed adhesive having a solid content concentration of 15% by weight was obtained. Prepared.

[Preparation Example 2] Hard coat treatment agent a, coating composition b
An ultraviolet curable resin composition (Desolite Z-7524 manufactured by JSR Corporation: the composition is shown in Table 1. The solid content concentration is 53.2%) is converted to 45% by weight with methyl ethyl ketone. The hard coat treating agent a consisting of the coating composition containing no particles was obtained.
With respect to the obtained hard coat treatment agent a, 1% by weight of the irregularly shaped polymer particles (SX8707C-04, number average particle diameter 4.5 μm, manufactured by JSR Corporation) with respect to the total solid content is obtained by using methyl ethyl ketone, and the solid content concentration Was diluted to 40% by weight and stirred to prepare coating composition b.

[Production Example 1] Laminated film B-1
Coating composition b was applied to one side of cyclic olefin polymer film A-2 by the gravure reverse method. The coated surface was dried at 80 ° C. for 60 seconds and irradiated with an ultraviolet ray of 150 mJ / cm ² to obtain a film having a particle-containing resin layer having a thickness of 1.7 μm.
Next, using the hard coat treatment agent a, a hard coat layer was similarly formed on the opposite side of the film, and a laminated film B-1 having a resin layer with a film thickness of 1.7 μm on both sides was formed. Table 2 shows the results of measuring or evaluating various physical properties of the obtained laminated film B-1.

[Production Example 2] Laminated film B-2
A laminated film B-2 was obtained in the same manner as in Production Example 1 except that the cyclic olefin polymer film A-1 was used instead of the cyclic olefin polymer film A-2. The results of measuring or evaluating various physical properties of the obtained laminated film B-2 are also shown in Table 2.

[Preparation Example 3] Coating solution for forming an easy-adhesion layer In a reactor equipped with a stirrer and a reflux condenser, an alkoxy-terminated polysiloxane with Mw = 20,000 (manufactured by GE Toshiba Silicone Co., Ltd., trade name: XR31-B2733) ) 60 parts by weight, 40 parts by weight of hydroxy-terminated polydimethylsiloxane having a Mw = 4000 (manufactured by GE Toshiba Silicone Co., Ltd., trade name: YF-3800), 42 parts by weight of toluene, and di-i-propoxy-ethylacetate 0.2 parts by weight of a 75% diluted solution of isopropyl alcohol in aluminum acetate was added and mixed, followed by dealcoholization reaction at 80 ° C. for 3 hours while stirring. Subsequently, 288 parts by weight of methyl isobutyl ketone, 70 parts by weight of methanol, 80 parts by weight of water and 12 parts by weight of triethylamine were added, and a hydrolysis / condensation reaction was performed at 60 ° C. for 3 hours. Thereafter, the reaction solution obtained was neutralized with oxalic acid, and after removing the aqueous phase (lower layer), washing with water and removal of the aqueous phase were carried out three times, and then the solvent was distilled off to obtain a polyfunctional compound with Mw = 30,000. Polysiloxane was obtained. 100 parts by weight of methyl isobutyl ketone was added to this polyfunctional polysiloxane to obtain a polysiloxane solution (I) having a solid concentration of 50% by weight.
120 parts by weight of powdered zirconium oxide fine particles (primary average particle size: 20 nm), 160 parts by weight of the polysiloxane solution (I) (80 parts by weight in terms of solid content) as a polysiloxane component, and 0.1 parts by weight of triethylamine And 720 parts by weight of diisobutyl ketone are added to a container, 2000 parts by weight of 0.1 mm diameter zirconia beads are added to the mixture, and the fine particles are dispersed for 6 hours using a paint shaker, and the solid content concentration is 20% by weight. An easy-adhesion layer-forming coating solution comprising a metal oxide fine particle-containing polysiloxane composition was obtained.

[Example 1] Conductive laminated film C-1
The surface of the particle-containing resin layer in the laminated film B-1 is subjected to a corona discharge treatment of 50 W · min / m ² in the air, and then the easy-adhesion layer-forming coating solution is applied with a wire bar having a wet film thickness of 6 μm. The coated layer was dried at 110 ° C. for 3 minutes to form an easy adhesion layer.
On the surface of the formed easy-adhesion layer, a transparent conductive layer was formed by a sputtering method under the following conditions using a target containing indium and tin under an argon gas inflow to obtain a conductive laminated film C-1. . It was 550 ohms / square when the surface resistance value in the transparent conductive layer of the obtained electroconductive laminated film C-1 was measured. Table 3 shows the results of measurement and evaluation of various physical properties.

(conditions)
Substrate temperature: 50 ° C. or less Target: In ₂ O ₃ / SnO ₂ = 90/10 (weight ratio) oxide Atmosphere: Under argon flow Argon flow rate: 100 to 500 sccm
Output: 1 ~ 1.5Kw

[Comparative Example 1]
Instead of the laminated film B-1, a conductive laminated film C-2 was obtained in the same manner as in Example 1 except that the laminated film B-2 was used. The results of measuring and evaluating various physical properties are also shown in Table 3.
[Comparative Example 2]
Example 1 except that the cyclic olefin polymer film A-2 was used instead of the laminated film B-1 and one side of the cyclic olefin polymer film A-2 was used instead of the surface of the particle-containing resin layer. Similarly, a conductive laminated film C-3 was obtained. Table 3 shows the results of measurement and evaluation of various physical properties.

[Example 2] Production of polarizing plate and touch panel The mixed adhesive obtained in Preparation Example 1 was applied to one side of the polarizing film obtained in Production Example 3, and the conductive laminated film C-1 was made transparent conductive. The polarizing plate D-1 of the present invention was obtained by laminating so that the surface opposite to the film was in contact with the polarizing film. In addition, it bonded together so that the absorption axis of a polarizing film and the optical axis of the film which has a quarter wavelength plate function in an electroconductive laminated film may make an angle of 45 degrees.
Two polarizing plates D-1 are placed on a liquid crystal display element so as to overlap each other through a spacer so that the transparent conductive film surfaces face each other at an angle at which the absorption axes of the polarizing films are orthogonal to each other. An inventive touch panel was obtained. At this time, in FIG. 1 centering on the display screen, the absorption axis of the polarizing film in the polarizing plate close to the display screen is in the 45 ° direction, and the optical axis of the film having a quarter-wave plate function in the polarizing plate is 0. The polarizing film has an absorption axis of 135 ° in the other polarizing plate, and the optical axis of the film having a quarter-wave plate function in the polarizing plate is in the 90 ° direction. did.
The obtained touch panel was evaluated for contrast and visibility. The results are shown in Table 4.

[Comparative Example 3]
A touch panel was obtained in the same manner as in Example 2 except that the conductive laminated film C-2 was used instead of the conductive laminated film C-1. The obtained touch panel was evaluated for contrast and visibility. The results are also shown in Table 4.
[Comparative Example 4]
A touch panel was obtained in the same manner as in Example 2 except that the conductive laminated film C-3 was used instead of the conductive laminated film C-1. The obtained touch panel was evaluated for contrast and visibility. The results are also shown in Table 4.

  According to the present invention, it is possible to obtain a touch panel that does not cause reflection due to light reflection, has high contrast, and is excellent in visibility. Further, even when heat treatment in the touch panel manufacturing process is performed, a touch panel with extremely small change in phase difference and extremely small change in resistance value can be obtained. The touch panel of the present invention can be suitably used for a display having input means for an electronic device such as a personal digital assistant (PDA), a notebook PC, an OA device, a medical device, or a car navigation system.

Claims (3)

It consists of a cyclic olefin polymer obtained by (co) polymerizing a monomer containing at least one compound represented by the following formula (1), and has an in-plane retardation of 128 for transmitted light having a wavelength of 550 nm. A film having a 1/4 wavelength plate function in a range of ˜148 nm, a particle-containing resin layer, and a transparent conductive layer having a weight ratio of indium oxide to tin oxide of 95: 5 to 99: 1 Conductive laminated film.

(Wherein R ^{1 to} R ⁴ each independently represents a hydrogen atom; a halogen atom; or a monovalent organic group that may contain oxygen, nitrogen, sulfur or silicon;
R ¹ and R ² and R ³ and R ⁴ may be independently bonded to each other to form an alkylidene group,
R ¹ and R ² , R ³ and R ⁴ , and R ² and R ³ may be independently bonded to each other to form a monocyclic or polycyclic carbocyclic or heterocyclic ring,
x represents an integer of 0 to 3, and y represents 0 or 1. ) A conductive laminate film according to claim 1, which is laminated on a polarizing film. A touch panel comprising the polarizing plate according to claim 2.

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