JP2012066477A - Laminated film having hard coat layer, and laminated film for touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated film which is excellent in optical properties such as transparency and is produced easily, and to provide a laminated film for touch panels.SOLUTION: A base material sheet of the laminated film comprises a thermoplastic norbornene-based resin. The laminated film is obtained by laminating a first hard coat layer on one surface of the base material sheet and a second hard coat layer on the other opposite surface thereof. The base material sheet has ≤10 nm in-plane retardation and ≤10 nm thickness-direction retardation or 120-150 nm in-plane retardation and 60-225 nm thickness-direction retardation. Each of the first hard coat layer and the second hard coat layer contains fine particles having ≤500 nm average primary particle size (D50) or two or three kinds of particles having ≤500 nm average primary particle sizes different from one another.

Description

  The present invention relates to a laminated film or a laminated film for a touch panel, and more particularly relates to a laminated film and a laminated film for a touch panel that are excellent in optical properties such as excellent transparency and easy to produce.

  In electronic devices such as notebook computers, OA devices, medical devices, car navigation systems, and personal digital assistants (PDPs), touch panels that have input means on display are widely used. A transparent touch panel has the structure arrange | positioned so that the electrode surfaces of two transparent electrode layers may face each other. As a touch panel system, an optical type, an ultrasonic type, an electromagnetic induction type, and a resistive film type are generally used.

  As the electrode, as the conductive film, a metal oxide such as indium tin oxide or tin antimonic acid or a metal thin film such as gold, palladium, aluminum, silver, or the like is used. In recent years, a touch panel using a conductive transparent sheet using a polymer film as a substrate instead of a glass substrate that is easily damaged has been studied.

  The polymer film has various properties such as mechanical properties, surface smoothness, hardness, heat resistance, solvent resistance, scratch resistance, moisture permeability, sufficient transparency and optical properties even when the thickness is large. Must meet the characteristics. Accordingly, plastic substrates such as polycarbonate (PC), polymethyl methacrylate (PMMA) and polyethylene terephthalate (PET) instead of glass, and film substrates such as thermosetting acrylic resins and thermosetting epoxy resins have been used.

  In patent document 1, although the electroconductive film which laminated | stacked ITO on the quarter wavelength plate is described, when ITO is sputtered directly, there exists a possibility of being damaged at the time of conveyance. Further, Patent Document 2 includes one provided with a double-sided hard cord layer of an alicyclic structure-containing polymer resin. However, a protective film is required for winding. Patent Document 3 describes that a protective layer is formed on a norbornene-based resin film and a conductive paint is applied. However, problems such as adhesion and pattern formation method remain.

  Also, polycarbonate (PC), polymethylmethacrylate (PMMA), polyethylene terephthalate (PET), etc., which are widely used as molding materials for optical applications, have a large photoelastic coefficient, so that stress on the touch panel is high. When used in such a member, birefringence may increase, water absorption is high, and heat resistance is insufficient. Furthermore, PET has a problem that it is insufficient in terms of visibility, contrast, and the like when a transparent touch panel is used by being superimposed on a liquid crystal display element.

JP 2009-226932 A JP-A-11-282625 JP 2009-245935 A

When used as a base material for a touch panel, the base film for forming the transparent conductive layer is required to have optical isotropy, and a film having no optical isotropy such as a conventionally used PET film should be used. I can't. A film made of an optical plastic such as polycarbonate (PC) or polymethyl methacrylate (PMMA) has a small birefringence value, but has a large water absorption and insufficient heat resistance. Therefore, a thermoplastic norbornene resin excellent in transparency, moisture resistance and water absorption is promising as an optical film.
An optical film made of a thermoplastic norbornene resin is not only excellent in water absorption, but also can control the in-plane and thickness direction retardation values. Furthermore, by performing uniaxial or biaxial stretching, the in-plane retardation value (Re) for transmitted light of 550 nm of visible light shows 120 to 150 nm, and the retardation value (Rth) in the thickness direction is 60 to 225 nm. It is possible to mold a substrate having a 1/4 wavelength plate function in the range.

  However, when a base material made of a thermoplastic norbornene resin is used alone, there is a problem that it is inferior in mechanical properties, surface smoothness, hardness, heat resistance, and solvent resistance. Furthermore, there is a problem that the film cannot be wound without the masking film.

Under such circumstances, the present inventor exhibits mechanical properties, surface smoothness, hardness, heat resistance, solvent resistance, scratch resistance, moisture permeability, sufficient transparency and optical properties even when the thickness is large. In order to eliminate masking, a thermoplastic norbornene-based resin is used, and further, three or less kinds of fine particles are combined to realize blocking prevention, and the present invention has been completed by finding that it can be wound without masking.

That is, the present invention
[1] The base sheet is made of a thermoplastic norbornene resin, the first hard coat layer is laminated on the surface, and the second hard coat layer is laminated on the opposite base sheet surface,
The substrate sheet has an in-plane retardation of 10 nm or less and a thickness direction retardation of 10 nm or less, or an in-plane retardation of 120 to 150 nm, and a thickness direction retardation of 60 to 225 nm,
The first hard coat layer and the second hard coat layer contain fine particles having a primary average particle diameter (D50) of 500 nm or less, or two or three kinds of particles having different primary particle diameters of 500 nm or less. Laminated film.

The laminated film according to [1], wherein the film formed by laminating the first hard coat layer and the second hard coat layer has a haze of 1% or less.
[3] The laminated film according to [1] or [2], wherein a difference in contact angle in distilled water between the first hard coat layer and / or the second hard coat layer and the base sheet is 10 ° or more.
[4] A laminated film for a touch panel in which a conductive film is further laminated on the first hard coat layer and / or the second hard coat layer of the laminated film according to [1] or [2].

[5] The laminated film for a touch panel according to [4], wherein the conductive film is made of a conductive polymer containing ITO, IZO, or polythiophene.
[6]
The laminated film for a touch panel according to [4] or [5], wherein the conductive film is a uniform plane or patterned.
[7]
The laminated film for a touch panel according to any one of [4] to [6], wherein the fine particles include a hard coat layer that is the same component as the silicon oxide and / or the conductive layer.
It is.

  The laminated film for a touch panel of the present invention can prevent blocking and make it maskless by a combination of 1 to 3 particle sizes. This greatly contributes to cost. Further, there is an advantage that the conductive film can be used not only for the resistive film system but also for the electrostatic capacity system by using not only ITO and IZO but also a conductive polymer, and patterning them.

FIG. 1 is a view for explaining an example of the structure of the laminate of the present invention. FIG. 2 is a view for explaining an example of the structure of the laminate of the present invention.

The present invention will be described in detail below.
According to one aspect of the present invention, the laminated film for a touch panel of the present invention has at least one kind on both surfaces of a base sheet formed from a thermoplastic norbornene-based resin having an in-plane retardation of 10 nm or less and a thickness direction. The active energy ray-curable resin and a laminate having a hard coat layer formed of fine particles.
According to another aspect of the present invention, the hard coat film of the present invention is a uniaxially or biaxially stretched thermoplastic norbornene-based resin having an in-plane retardation (Re, hereinafter) with respect to transmitted light having a visible light of 550 nm. (Also referred to as a retardation value) is 120 to 150 nm and the thickness direction retardation (Rth) is 60 to 225 nm. Both surfaces of the substrate are formed of at least one active energy ray-curable resin and fine particles. It consists of a laminated body which has a hard-coat layer.

(Base material sheet)
In the present invention, the thermoplastic norbornene-based resin used for the base material sheet is a resin known in JP-A-3-14882, JP-A-3-122137, JP-A-4-63807, and the like. Ring-opening polymer of a monomer, a hydrogenated product thereof, an addition polymer of a norbornene monomer, an addition polymer of a norbornene monomer and an olefin, a modified product of these polymers, etc. .

  Norbornene monomers include, for example, norbornene, its alkyl, alkylidene, aromatic substituted derivatives and halogens, hydroxyl groups, ester groups, alkoxy groups, cyano groups, amide groups, imide groups, silyl groups of these substituted or unsubstituted olefins. Polar group substitution products such as 2-norbornene, 5-methyl-2-norbornene, 5,5-dimethyl-2-norbornene, 5-ethyl-2-norbornene, 5-butyl-2-norbornene, 5-ethylidene 2-norbornene, 5-methoxycarbonyl-2-norbornene, 5-cyano-2-norbornene, 5-methyl-5-methoxycarbonyl-2-norbornene, 5-phenyl-2-norbornene, 5-phenyl-5-methyl 2-norbornene, 5-hexyl-2-norboernene, 5-octyl 2-norbornene, 5-octadecyl-2-norbornene and the like; monomers obtained by adding one or more cyclopentadiene to norbornene, derivatives and substitutes thereof similar to the above, for example, 1,4: 5,8-dimethano- 1,2,3,4,4a, 5,8,8a-2,3-cyclopentadienooctahydronaphthalene, 6-methyl-1,4: 5,8-dimethano-1,4,4a, 5 6,7,8,8a-octahydronaphthalene, 1,4: 5,10: 6,9-trimethano-1,2,3,4,4a, 5,5a, 6,9,9a, 10,10a- Dodecahydro-2,3-cyclopentadienoanthracene and the like; a monomer having a polycyclic structure which is a multimer of cyclopentadiene, and derivatives and substitutes thereof similar to the above, for example, dicyclopentadiene, 2,3-dihydrodicyclo Penta Adene of cyclopentadiene and tetrahydroindene, etc., derivatives and substitutes similar to those mentioned above, for example, 1,4-methano-1,4,4a, 4b, 5,8,8a, 9a-octahydro Fluorene, 5,8-methano-1,2,3,4,4a, 5,8,8a-octahydro-2,3-cyclopentadienonaphthalene and the like.

  Monomers having a norbornene structure can be used singly or in combination of two or more. Examples of the polar group include a hetero atom or an atomic group having a hetero atom. Examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfone group. To obtain a film with a small saturated water absorption rate. It is preferable that the amount of polar groups is small, and it is more preferable that there are no polar groups.

  The norbornene-based monomer may be polymerized by a known method. If necessary, the norbornene-based monomer is a thermoplastic saturated norbornene-based resin by copolymerizing with another copolymerizable monomer or by hydrogenation. It can be set as a system polymer hydrogenated product. In addition, polymers and polymer hydrogenated products can be converted into α, β-unsaturated carboxylic acids and / or derivatives thereof, styrenic hydrocarbons, olefinic unsaturated bonds and organosilicon compounds having hydrolyzable groups, unsaturated You may modify | denature using an epoxy monomer.

  In the present invention, the number average molecular weight of the thermoplastic norbornene resin is 10,000 to 200,000, preferably 15,000 in terms of polystyrene measured by GPC (gel permeation chromatography) method using a toluene solvent. ~ 100,000, more preferably 20,000-50,000. Further, when the thermoplastic norbornene resin has an unsaturated bond in the molecular structure, it can be made into a thermoplastic saturated norbornene resin by hydrogenation. In the case of hydrogenation, the hydrogenation rate is 90% or more, preferably 95% or more, more preferably 99% or more, from the viewpoint of heat deterioration resistance, light deterioration resistance, and the like.

  The thermoplastic norbornene resin used in the present invention includes, as desired, an antioxidant such as phenol or phosphorus; an anti-aging agent such as phenol; an ultraviolet stabilizer such as benzophenone; an antistatic agent such as amine. Various additives such as lubricants such as esters of aliphatic alcohols, partial esters and polyols of polyhydric alcohols may be added. Further, other resins and the like can be mixed and used within a range not impairing the object of the present invention.

  The thermoplastic norbornene resin used in the present invention has a glass transition temperature of preferably 80 ° C. or higher, more preferably 100 to 250 ° C.

  In one embodiment of the present invention, a substrate sheet made of a thermoplastic norbornene resin needs to have a substrate that exhibits an in-plane retardation value of 10 nm or less and a thickness direction. Since it is necessary to pass light emitted from the backlight and light entering from the surface as it is, it is necessary to have optical isotropy having a small retardation (birefringence) value.

  Retardation is a phenomenon in which light incident on a crystal or other anisotropic material is divided into two light waves having vibration directions perpendicular to each other. When non-polarized light is incident on a material having birefringence, the incident light is divided into two. Both of the vibration directions are perpendicular to each other, one is called vertically polarized light and the other is called horizontally polarized light. The vertical ray is an extraordinary ray, the horizontal ray is an ordinary ray, the ordinary ray is a ray whose propagation speed does not depend on the propagation direction, and the extraordinary ray is a ray having a different speed depending on the propagation direction. In a birefringent material, there is a direction in which the velocities of these two rays coincide with each other, and this is called an optical axis. The retardation difference value Δnd is expressed by Δnd = (nx−ny) d. Here, d is the thickness of the sample, and nx and ny are the refractive indexes of the sample.

  The base material used in the present invention is a thermoplastic norbornene resin formed into a film. The molding method is not particularly limited. Common molding methods for thermoplastic resins, such as injection molding, melt extrusion, hot pressing, solvent casting, and stretching, can be used.

  In the present invention, the in-plane and thickness direction retardation values are preferably 10 nm or less. When the retardation value is large enough to exceed 10 nm, the light emitted from the backlight and the light passing through the polarizing plate are divided into two light waves having vibration directions perpendicular to each other, and a phase shift of the light wave occurs. As a result, the circularly polarized light becomes elliptically polarized light, resulting in a color different from the color emitted from the backlight or uneven color.

  The method for controlling the in-plane and thickness direction retardation values of the substrate sheet used in the present invention is not particularly limited. Specific examples of the method include film thickness control and film forming speed. Moreover, by performing the heat treatment of the hard coat film having the hard coat layer formed on both sides, the phase difference can be controlled without being deformed, so that the phase difference can be controlled.

The base sheet made of a thermoplastic norbornene resin is a film having a thickness of preferably 20 μm to 250 μm, more preferably 23 μm to 188 μm.
The hard coat layer constituting the hard coat film will be described later.

  The substrate sheet used in another embodiment of the present invention is a stretched film made of a uniaxially or biaxially stretched thermoplastic norbornene resin, and has an in-plane retardation value (Re) for transmitted light of visible light of 550 nm. Is a film having the characteristics of a quarter wave plate in which the retardation value (Rth) in the thickness direction is in the range of 60 to +225 nm.

The in-plane retardation (Re) is a value obtained by multiplying the difference between the refractive index nx in the in-plane slow axis direction and the refractive index ny in the direction perpendicular to the slow axis by the average thickness d of the film. (Re = (nx−ny) × d).
Further, the retardation in the thickness direction (Rth) is represented by Rth (= ((nx + ny) / 2−nz) × d, where nx is the refractive index in the in-plane slow axis direction; The refractive index in the direction perpendicular to the slow axis; nz is the refractive index in the thickness direction; d is the average thickness of the film.

  The in-plane retardation value (Re) of the substrate sheet is preferably 120 nm to 150 nm, and more preferably 130 nm to 150 nm. The retardation value (Rth) in the thickness direction is preferably 60 nm to 225 nm. By having the said base material sheet, reflected light can be prevented and there exists an effect that a high-contrast touch panel is obtained.

  In the present invention, the variation in retardation (Re) in the in-plane direction is preferably within 10 nm, more preferably within 5 nm, and particularly preferably within 2 nm. By setting the variation in retardation Re in the in-plane direction within the above range, it is possible to improve the display quality when used as a retardation film for a liquid crystal display device.

  The retardation value (Rth) in the thickness direction of the substrate sheet is preferably 60 nm to +225 nm. More preferably, it is 60 nm-150 nm. The variation is preferably within 10 nm, more preferably within 5 nm, and particularly preferably within 2 nm. By having the said base material sheet, reflected light can be prevented and there exists an effect that a high-contrast touch panel is obtained.

  In the stretched film of the present invention, the content of residual volatile components is preferably 0.1% by weight or less, more preferably 0.05% by weight or less, and further preferably 0.02% by weight or less. If the content of residual volatile components is large, the optical characteristics may change over time. By setting the content of the volatile component within the above range, the dimensional stability can be improved, and the temporal change of the in-plane direction retardation (Re) and the thickness direction retardation (Rth) can be reduced.

  The stretched film is preferably obtained by uniaxially, biaxially or obliquely stretching an unstretched film obtained from a thermoplastic norbornene-based resin. The stretching method is not particularly limited, and examples thereof include a roll method, a float method longitudinal stretching method, a tenter method transverse uniaxial stretching and simultaneous biaxial stretching. Furthermore, as long as a long film can be continuously obliquely stretched, it is not particularly limited, and various types of stretching machines can be used.

  The temperature at which the unstretched film is obliquely stretched is preferably between Tg-30 ° C and Tg + 60 ° C, more preferably from Tg-10 ° C, where Tg is the glass transition temperature of the alicyclic structure-containing polymer resin. The temperature range is Tg + 50 ° C. Moreover, a draw ratio is 1.01-30 times normally, Preferably it is 1.01-10 times, More preferably, it is 1.01-5 times.

  The average thickness of the stretched film is preferably 20 to 80 μm, more preferably 30 to 60 μm, from the viewpoint of mechanical strength and the like. Moreover, since the thickness unevenness in the width direction of the stretched film affects the availability of winding, it is preferably 3 μm or less, more preferably 2 μm or less.

  The method for forming the unstretched film is not particularly limited, and a known forming method can be employed. For example, either a hot melt molding method or a solution casting method can be employed, but from the viewpoint of reducing volatile components in the sheet, it is preferable to use the hot melt molding method. The hot melt molding method can be further classified into a melt extrusion molding method, a press molding method, an inflation method, an injection molding method, a blow molding method, a stretch molding method, and the like. Among these, in order to obtain a stretched film having excellent mechanical strength and surface accuracy, it is preferable to use a melt extrusion molding method. A thermoplastic norbornene resin is molded. The molding method is not particularly limited. Common molding methods for thermoplastic resins, such as injection molding, melt extrusion, hot pressing, solvent casting, and stretching, can be used.

  The molding conditions are appropriately selected depending on the purpose of use and the molding method. In the case of the melt extrusion molding method, the cylinder temperature is preferably set in the range of preferably 100 to 600 ° C, more preferably 150 to 350 ° C.

  The thickness of the unstretched film can be appropriately determined according to the purpose of use of the stretched film obtained. The thickness of the film is preferably 10 to 300 μm, more preferably 30 to 200 μm, from the viewpoint of obtaining a uniform stretched film by a stable stretching process.

  The glass transition temperature (Tg) of a film having a 1/4 wavelength function made of a thermoplastic norbornene resin is preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and particularly preferably 150 ° C. or higher. If the Tg of the resin is too low, the heat resistance of the molded product is lowered.

Furthermore, when the hard coat layer is formed and the touch panel manufacturing process is taken into consideration, it is preferable to use those having a Tg of 120 ° C. or more and a photoelastic coefficient of 10 × 10 ⁻¹⁰ · Pa ⁻¹ or less. If the Tg is less than 120 ° C., the base sheet may be deformed or wrinkled due to the drying process of the hard coat, the stress when curing the active energy ray, the temperature when laminating the conductive layer, or the like. When the photoelastic coefficient exceeds 10 × 10 ⁻¹⁰ · Pa ⁻¹ , the in-plane and thickness direction retardation values easily change due to tensile stress such as bonding, and partially optically isotropic. There is a risk of disappearing.

In addition, the thermoplastic norbornene-based film in the present invention may be subjected to a surface treatment for the purpose of improving the adhesion with the hard coat layer. Examples of the surface treatment include plasma treatment, corona treatment, alkali treatment, and coating treatment. In particular, by using corona treatment, adhesion between the film made of the thermoplastic norbornene resin and the hard coat layer can be strengthened.
As corona treatment conditions, the irradiation dose of corona discharge electrons is preferably 1 to 1000 W / m ² / min. It is preferable that the contact angle with respect to the water of the thermoplastic norbornene-type film after the said corona treatment is 10-50 degrees. The coating may be performed immediately after the corona treatment or after neutralization. However, since the appearance of the hard coat layer is improved, it is preferable that the coating is performed after neutralization.

(Hard coat layer)
The hard coat layer is formed of fine particles and at least one active energy ray curable resin. The hard coat layer is a layer formed by coating and drying a coating composition in which particles and an active energy ray-curable resin are dispersed with various coaters and then curing the resin. When the hard coat layer is formed on both surfaces of the thermoplastic norbornene resin substrate sheet, it has excellent scratch protection and curl prevention.

  The active energy ray-curable resin used for forming the hard coat layer in the present invention is not particularly limited as long as it is a commonly used active energy ray-curable resin component for hard coat. In the pencil hardness test specified in JISK5600-5-4, an active energy ray-curable resin component capable of forming a cured film exhibiting a hardness of “HB” or higher is particularly preferable. Examples thereof include active energy ray-curable materials such as organic silicone, melamine, epoxy, acrylic, and urethane acrylate. Of these, urethane acrylate-based or polyfunctional acrylate-based ultraviolet curable resin component materials are preferable from the viewpoint of good adhesive strength and excellent toughness and productivity.

The fine particles used in the present invention are fine particles capable of adjusting the conductivity, refractive index and the like of the hard coat layer. As the fine particles, fine particles having a refractive index of 1.4 or more are preferable.
Examples of the fine particles include silica, tin-doped indium oxide (ITO), zinc-doped indium oxide (IZO), and the like. Among these, silica fine particles are particularly suitable as a component for adjusting the refractive index because they are excellent in the balance between adhesion to the substrate sheet and transparency. You may use these individually by 1 type or in combination of 3 or less types. Further, when the fine particles of the hard coat layer and the conductive layer described later are composed of the same component, an effect of improving the adhesion can be expected.

  The primary average particle diameter of the fine particles is 1 nm or more and 500 nm or less. Here, the average particle diameter refers to the number average particle diameter. The smaller the particle size, the lower the haze of the hard coat layer.

  The content of the fine particles is preferably 1 to 80 parts when the active energy ray-curable resin is 100 parts. When the content of the fine particles is within the above range, the optical properties such as haze value and total light transmittance are excellent.

When two to three kinds of fine particles are used in combination, a combination that satisfies the following formula is preferable for the combination of the average particle diameters of the fine particles.
d _i × 2 <d _{i + 1} <d _i × 4
In the formula, d represents the primary average particle diameter of the contained fine particles, and i represents the order of the size of the particles when the hard coat layer contains two or three kinds of fine particles. For example, when two types of particles having different primary average particle diameters are contained, the primary average particle diameter of the smaller fine particles is in the range of 2 to 4 times the primary average particle diameter of the larger fine particles. . Here, if it is less than 2 times, if it is less than 2, haze increases, and if it is above 4, the blocking effect is poor. Furthermore, a combination satisfying the following formula is preferable.
di × 2.5 <d _{i + 1} <d _i × 3.5

  The hard coat layer is obtained by applying a coating composition in which the active energy ray-curable resin and fine particles are dispersed to a base sheet using various coaters and drying the composition, and then curing the resin.

  Examples of the solvent for dissolving or dispersing the active energy ray-curable resin include alcohols such as methanol, ethanol, isopropanol, n-butanol and isobutanol; ethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol Glycols such as diethylene glycol monobutyl ether and diacetone glycol; aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as n-hexane and n-heptane; esters such as ethyl acetate and butyl acetate; methyl ethyl ketone; Ketones such as methyl isobutyl ketone; oximes such as methyl ethyl ketoxime; and combinations of two or more thereof.

  As the active energy ray, any of ultraviolet rays, electron beams and the like may be used. In the case of curing with ultraviolet rays, usually about 1 to 15 parts by weight of a photopolymerization initiator can be contained with respect to 100 parts by weight of the active energy ray-curable resin. Various known photopolymerization initiators 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.

  The hard coat layer is usually a mixture of active energy ray-curable resin, fine particles and, if necessary, a photopolymerization initiator, and dissolved or dispersed liquid is applied onto the substrate sheet, and the temperature is 60 to 120 ° C. The coating film can be obtained by drying with an active energy ray and then cured by irradiation. Examples of the coating method include wire bar coating, dipping, spraying, spin coating, roll coating, gravure coating, and die coating.

    As the active energy ray, any of ultraviolet rays, electron beams and the like may be used. The irradiation intensity and irradiation time of the active energy ray are not particularly limited, and irradiation conditions such as irradiation intensity and irradiation time can be appropriately set according to the active energy ray curable resin to be used.

  The film thickness of the hard coat layer is preferably 0.5 μm to 20 μm. More preferably, they are 0.5 micrometer-10 micrometers, More preferably, they are 0.5 micrometer-5 micrometers. In this case, when the film thickness is 5 μm or less, deterioration of the surface condition due to curing shrinkage can be suppressed to an extent that there is no problem. Some of the particles may be in a state where part of the particles protrudes 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.

  In order to suppress curling of the base sheet, it is preferable to use a hard coat layer applied on both sides of the base sheet that has a close shrinkage. More preferably, the hard coat layer is formed using the same hard coat solution, and the film thickness is also preferably substantially the same.

  In addition, when curling a hard coat film artificially and curling when it is made into a laminated body with a polarizing plate, a conductive layer, etc., the thickness of both surfaces of the hard coat layer may not be the same.

  The ten-point average height (Rz) of the hard coat layer surface is preferably 1.0 μm or less. More preferably, it is 0.5 μm or less. When the ten-point average height of the hard coat layer is in the above range, the adhesion with the conductive film is particularly excellent.

  It is preferable that the contact angle with respect to the water of a hard-coat layer has a difference of 10 degrees or more from a base sheet, without the surface treatment of a hard-coat layer. This is because when the contact angle of the hard coat layer is high, the adhesion is poor when the conductive layer such as ITO is laminated.

The pencil hardness of the hard coat layer is preferably HB or higher when measured according to JISK5600-5-4. More preferably, it is H or more.
The scratch resistance of the hard coat layer is preferably such that no scratches are visually confirmed when the surface of the hard coat layer of the hard coat film is reciprocated 10 times in a state where a load of 0.025 MPa is applied to steel wool # 0000. .
If the pencil hardness of the hard coat layer is HB or less or the scratch resistance is poor, scratches may occur in the process, or the transparent conductive film may be scratched during the formation of the conductive layer.

  The haze in the laminated film of the present invention is preferably 1% or less. The haze is also called haze value and represents the degree of haze and the degree of diffusion. For example, JISK-7136 is used by using a commercially available haze meter (product name “NDH 2000” manufactured by Nippon Denshoku Co., Ltd.). The haze (%) can be measured according to the above. When the haze is outside the above range, white blur occurs and the visibility of the touch panel decreases.

  In the laminated film for a touch panel of the present invention, the total light transmittance is preferably 90% or more. The total light transmittance is measured, for example, by using a commercially available haze meter (manufactured by Nippon Denshoku Co., Ltd., product name “NDH 2000”) and the like in accordance with JISK-7361. be able to. If the total light transmittance is lower than the following range, the visibility is lowered.

  The refractive index difference of the hard coat layer is preferably 5% or less with respect to the refractive index of the thermoplastic norbornene film. More preferably, it is within 2%. This is because interference unevenness occurs when the refractive index difference between the base sheet and the base sheet increases.

  The heat shrinkage rate (%) is preferably 1.5% or less when calculating the heat shrinkage rate by measuring the dimensional change after leaving the laminated film in a forced circulation dryer heated to 150 ° C. for 60 minutes. More preferably, it is 1.0% or less. If the heat shrinkage rate exceeds 1.5%, the touch panel may be deformed.

  The residual solvent (%) is allowed to stand for 30 minutes in a forced circulation dryer heated to 150 ° C., and the residual solvent is preferably 2.0% or less, more preferably 1.0% or less. is there. When the residual solvent exceeds 2.0%, the amount of the volatile solvent at the time of forming the conductive layer is increased, and the conductive layer may be defective.

(Conductive layer)
It is preferable to laminate a conductive layer directly on the hard coat layer of the present invention. The conductive layer only needs to be transparent and conductive, and conventionally known materials used for liquid crystal substrates and touch panels can be used.

  In the present invention, the conductive layer is not particularly limited, and any conductive material may be used. For example, examples of the conductive material include conductive polymers, conductive pastes such as silver paste and polymer paste, metal colloids such as gold and copper, metal oxides such as ITO, and the like. Specific examples of the material include tin-doped indium oxide (ITO), zinc-doped indium oxide (IZO), antimony or fluorine-doped tin oxide (ATO or FTO), and aluminum. Zinc oxide (AZO), cadmium oxide, cadmium-tin oxide, titanium oxide, zinc oxide, copper iodide and other metal oxides, or gold (Au), silver (Ag), platinum (Pt), palladium Examples thereof include metals such as (Pd). Among these, when the transparent conductive layer is used as a touch panel for a liquid crystal display element, a conductive polymer containing ITO, IZO, or polythiophene is most preferable from the viewpoints of light transmittance and durability.

  As a conductive polymer, for example, polythiophene or polythiophene derivative, polyaniline or polyaniline derivative, polypyrrole, polyacetylene, polyparaphenylene, polyphenylene vinylene, etc. in a polymer matrix such as halogen, Lewis acid, proton acid, transition metal halide It is doped with a dopant such as and exhibits excellent conductivity. As the organic conductive polymer, polythiophene or polythiophene derivatives, polyaniline or polyaniline derivatives are particularly preferable.

  In the present invention, when the conductive layer is laminated, a silicon compound layer may be laminated as an intermediate layer. This is because the adhesion with a conductive film such as ITO is further improved by using the silicon compound as an intermediate layer.

  The formation of the conductive layer is not particularly limited, and examples thereof include a sputtering method, a vacuum evaporation method, a CVD method, an ion plating method, a sol-gel method, and a coating method.

  The thickness of the conductive layer is not particularly limited, but is preferably 10 to 200 nm. The surface resistivity of the conductive layer is not particularly limited, but is preferably about 100 to 1000Ω / □.

  The conductive layer may be patterned. In the case of ITO and IZO, there is a mesh pattern formed by pattern exposure / development processing, specifically, a mesh-like and linear lattice pattern in which straight lines are substantially orthogonal, and conductive portions between intersections are There are a wavy lattice pattern having at least one curve, a diamond-like pattern, and the like.

  In the case where the conductive layer is a conductive polymer, an arbitrary shape can be imparted by screen printing or gravure printing.

(Other layers)
The hard coat film of the present invention may have a low refractive index layer on the hard coat layer for the purpose of improving the transmittance in the visible light region. Here, the low refractive index layer refers to a layer having a refractive index lower than that of the hard coat layer. The refractive index of the low refractive index layer may satisfy the above conditions, but is preferably 1.39 or less, more preferably 1.38 or less and 1.25 or more. By satisfying the above preferable conditions, a low refractive index layer excellent in the balance between antireflection performance, scratch resistance and strength is formed.

  The material constituting the low refractive index layer is not particularly limited, but airgel is preferable in that the refractive index can be easily controlled and the water resistance is excellent. The airgel is a transparent porous body in which minute bubbles are dispersed in a matrix. The size of the bubbles is mostly 200 nm or less, and the bubble content is usually 10% by volume to 60% by volume, preferably 20% by volume to 40% by volume. Specific examples of the airgel in which minute bubbles are dispersed include silica aerogel and a porous body in which hollow particles are dispersed in a matrix.

  Silica airgel is a wet state composed of a silica skeleton obtained by hydrolysis polymerization reaction of alkoxysilane as disclosed in US Pat. No. 4,402,927, US Pat. No. 4,432,956, US Pat. No. 4,610,863 and the like. The gel compound can be produced by drying in a supercritical state above the critical point of the solvent in the presence of a solvent (dispersion medium) such as alcohol or liquefied carbon dioxide. In supercritical drying, for example, a gel compound is immersed in liquefied carbon dioxide, and all or part of the solvent contained in the gel compound is replaced with liquefied carbon dioxide having a critical point lower than that of the solvent. It can be carried out by drying under supercritical conditions of a single system of or a mixed system of carbon dioxide and a solvent. Silica airgel may be produced in the same manner as described above using sodium silicate as a raw material, as disclosed in US Pat. No. 5,137,279, US Pat. No. 5,124,364, and the like.

  Here, as disclosed in JP-A-5-279011 and JP-A-7-138375, the gel-like compound obtained by hydrolysis and polymerization reaction of alkoxysilane as described above is hydrophobized. It is preferable to impart hydrophobicity to the silica airgel. Hydrophobic silica airgel imparted with hydrophobicity as described above can prevent moisture, water, and the like from entering, and prevent the performance of the silica airgel from being degraded in refractive index, light transmittance, and the like.

  This hydrophobization treatment step can be performed before or during supercritical drying of the gel compound. The hydrophobization treatment is performed to make the hydrophobization by reacting the hydroxyl group of the silanol group present on the surface of the gel compound with the functional group of the hydrophobization treatment agent and replacing it with the hydrophobic group of the hydrophobization treatment agent. . As a method of performing the hydrophobization treatment, the gel is immersed in a hydrophobization treatment solution in which the hydrophobization treatment agent is dissolved in a solvent, mixed, and so on. There is a method in which the hydrophobization reaction is performed by heating accordingly.

  Examples of the solvent used for the hydrophobic treatment include methanol, ethanol, isopropanol, xylene, toluene, benzene, N, N-dimethylformamide, hexamethyldisiloxane, and the like, but the hydrophobic treatment agent can be easily dissolved. And what is necessary is just to be able to substitute for the solvent which the gel before hydrophobization treatment contains, and it is not limited to these. Further, when supercritical drying is performed in a later step, a medium that can be easily supercritically dried, such as methanol, ethanol, isopropanol, liquefied carbon dioxide, or the like, is preferable. Examples of the hydrophobizing agent include hexamethyldisilazane, hexamethyldisiloxane, trimethylmethoxysilane, dimethyldimethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane, trimethylethoxysilane, dimethyldiethoxysilane, and methyltriethoxysilane. Etc.

  The refractive index of silica airgel can be freely changed by the raw material compounding ratio of silica airgel. The formation method of the low refractive index layer made of silica aerogel is not particularly limited. For example, the gel compound is coated on the hard coat layer by a known coating method, and the supercritical drying is performed. The method of forming is mentioned. Further, the hydrophobization treatment may be performed before or during supercritical drying. In the supercritical drying, for example, the gel compound is immersed in liquefied carbon dioxide, and all or a part of the solvent containing the gel compound is replaced with liquefied carbon dioxide having a lower critical point than the solvent. It can be carried out by drying under supercritical conditions of a single system of carbon dioxide or a mixed system of carbon dioxide and a solvent.

  Examples of the porous body in which the hollow particles are dispersed in the matrix include porous bodies as disclosed in JP-A Nos. 2001-233611 and 2003-149642. The material used for the matrix is selected from materials that meet conditions such as the dispersibility of the hollow particles, the transparency of the porous body, and the strength of the porous body. For example, a polyester resin, an acrylic resin, a urethane resin, a vinyl chloride resin, Examples thereof include hydrolyzable organic silicon compounds such as epoxy resins, melamine resins, fluororesins, silicone resins, butyral resins, phenol resins, vinyl acetate resins and alkoxysilanes, and hydrolysates thereof. Among these, acrylic resin, epoxy resin, urethane resin, silicone resin, hydrolyzable organosilicon compound and hydrolyzate thereof are preferable from the viewpoint of dispersibility of the hollow particles and the strength of the porous body. Moreover, what was mentioned above can be used as a hollow particle.

The hollow fine particles are not particularly limited, but inorganic hollow fine particles are preferable. Examples of the inorganic compound constituting the inorganic hollow fine particles include SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , TiO ₂ , ZrO ₂ , SnO ₂ , Ce ₂ O ₃ , P ₂ O ₅ , Sb ₂ O ₃ , MoO _{3. , ZnO 2, WO 3, TiO} 2 -Al 2 O 3, TiO 2 -ZrO 2, In 2 O 3 -SnO 2, Sb 2 O 3 -SnO 2 or the like can be exemplified. In addition, said "-" shows that it is complex oxide. Among these, silica-based hollow fine particles are particularly preferable. The solvent or gas may be present in the pores of the porous material. If the removal amount of the constituent components of the core particles at this time increases, the volume of the hollow part of the hollow particles increases and hollow particles having a low refractive index are obtained. By using the hollow particles, the low refractive index layer can be simplified. The antireflection performance can be improved.

  The particle size of the hollow particles is preferably in the range of 5 nm to 2,000 nm, and more preferably in the range of 20 nm to 100 nm. When the particle size of the hollow particles is within the above range, the transparency of the low refractive index layer can be maintained. Here, the particle diameter of the hollow particles is a number average particle diameter by observation with a transmission electron microscope.

  The hollow particles can be produced based on, for example, a method described in JP-A-2001-233611. Commercially available hollow particles may also be used. In addition, the hollow particles are physically dispersed in the dispersion liquid or coating liquid, such as plasma discharge treatment or corona discharge treatment, in order to stabilize the dispersion or to increase the affinity and binding properties with the binder component. Surface treatment, chemical surface treatment with a surfactant, a coupling agent, or the like may be performed. A hydrophilic group such as a hydroxyl group or an acryloyl group may be introduced on the surface of the hollow particle by a method of reacting the hollow particle with a surfactant or a coupling agent.

In the laminated film of the present invention, a polarizing film may be formed on one side of the laminated film. Moreover, you may bond together with a polarizing plate. The polarizer is not particularly limited as long as it has a polarization function. For example, a polyvinyl alcohol (PVA) type or polyene type polarizer can be used. A polarizer is not specifically limited by the manufacturing method.
Further, a polarizing plate can be formed by adhering a polarizing film and a polarizing plate to a surface opposite to the transparent conductive layer of a film having a hard coat layer laminated on both sides with a pressure-sensitive adhesive.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples, and may be arbitrarily changed without departing from the gist of the present invention and its equivalent scope. Can be implemented.

(Test method, measurement method)
I. Adhesion (scratch resistance)
In a state where a load of 0.025 MPa was applied to Steel Wool # 0000, the surface of the hard coat layer of the hard coat film was reciprocated 10 times, and the surface state after the reciprocation was visually observed.
(Double-circle): A damage | wound is not recognized.
○: There are 3 or more streak scratches. (Limit passed)
X: There are 8 or more streak scratches.
II. It measured using the haze meter (Nippon Denshoku make, product name "NDH 2000") with the haze hard coat film (laminated film before laminating | stacking an electrically conductive film).

III. Total light transmittance Measured with a touch panel laminated film using a haze meter (manufactured by Nippon Denshoku Co., Ltd., product name “NDH 2000”).
IV. A linear polarizing plate was placed on the laminated film for a touch panel produced with reflectance, and measurement was performed using (JASCO, product name “V-550”).

V. Adhesiveness It evaluated by what is called a cross-cut peel test method. In other words, from the top of the antifouling layer, with a cutter, 11 cuts that intersect each other vertically and horizontally at 1 mm intervals are made, 100 1 mm square grids are made, and cellophane adhesive tape [Sekisui Chemical Co., Ltd.] is applied, and adhesive tape The number of eyes that did not peel in 100 eyes was shown by a test in which the film was pulled and peeled in a direction perpendicular to the surface.
○: 100/100 (number without peeling)
Δ: 95 to 99/100 (number without peeling)
X: 0 to 94/100 (number without peeling)
VI. Contact angle measurement A contact angle measuring device (manufactured by Kyowa Interface Science Co., Ltd., product name “DM500”) was used to measure the contact angle after 2 seconds of dropping distilled water.

VII. Create a 2000m roll with a blocking tension of 150N, and store it for one month in a storage warehouse at 60 ° C.
○: No change in appearance.
Δ: Sounds but no change in appearance.
×: There is a trace that looks stuck to the appearance.

Preparation Example 1 (Preparation of hard coat layer forming composition H1)
Silica particles (CIK Nanotech Co., Ltd., number average particle size 30 nm) 40 are added to 100 parts of urethane acrylate oligomer containing 6 or more functional acryloyl groups (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “UV-7640B”). Part and a photopolymerization initiator (product name “IRGACURE184” manufactured by Ciba Specialty Chemicals Co., Ltd.) 6 parts are added and stirred at 2000 rpm for 5 minutes using a stirrer to obtain composition H1 for forming a hard coat layer. It was.

Preparation Example 2 (Preparation of composition H2 for forming a hard coat layer)
Silica particles (CIK Nanotech Co., Ltd., number average particle size 30 nm) 40 are added to 100 parts of urethane acrylate oligomer containing 6 or more functional acryloyl groups (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “UV-7640B”). Part, silica particles (CIK Nanotech Co., Ltd., number average particle size 100 nm) 10 parts, silica particles (CIK Nanotech Co., Ltd., number average particle size 250 nm) 5 parts and photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.) , Trade name “IRGACURE184”) was added and stirred for 5 minutes at 2000 rpm using a stirrer to obtain composition H2 for forming a hard coat layer.

Preparation Example 3 (Preparation of hard coat layer forming composition H3)
To 100 parts of urethane acrylate oligomer (trade name “UV-7640B” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) containing 6 or more functional acryloyl groups, ITO particles (CIK Nanotech Co., Ltd., number average particle size 30 nm) 40 Part, silica particles (CIK Nanotech Co., Ltd., number average particle size 100 nm) 10 parts, silica particles (CIK Nanotech Co., Ltd., number average particle size 250 nm) 5 parts and photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.) , Trade name “IRGACURE184”) was added, and the mixture was stirred for 5 minutes at 2000 rpm using a stirrer to obtain composition H3 for forming a hard coat layer.

Preparation Example 4 (Preparation of composition H4 for forming a hard coat layer)
To 100 parts of a urethane acrylate oligomer containing 6 or more functional acryloyl groups (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “UV-7640B”), a photopolymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., trade name “ 6 parts of IRGACURE184 ") was added, and the mixture was stirred at 2000 rpm for 5 minutes using a stirrer to obtain composition H4 for forming a hard coat layer.

Preparation Example 5 (Preparation of composition H5 for forming a hard coat layer)
Silica particles (CIK Nanotech Co., Ltd., number average particle size 30 nm) 40 are added to 100 parts of urethane acrylate oligomer containing 6 or more functional acryloyl groups (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name “UV-7640B”). Part, silica particles (CIK Nanotech Co., Ltd., number average particle size 100 nm) 10 parts, silica particles (CIK Nanotech Co., Ltd., number average particle size 550 nm) 5 parts, photopolymerization initiator (Ciba Specialty Chemicals Co., Ltd.) , Trade name “IRGACURE184”) was added and stirred for 5 minutes at 2000 rpm using a stirrer to obtain composition H5 for forming a hard coat layer.

Example 1
As a base sheet having a retardation of 10 nm or less, a product name “ZEONOR FILM (registered trademark) ZF16 (water contact angle 92 °)” (hereinafter abbreviated as ZF) having a thickness of 100 μm was used. On the base material sheet, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. A transparent electrode excellent in crystallinity was formed by sputtering ITO on H2 at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Example 2)
A thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., ZF) was used as a substrate sheet having a retardation of 10 nm or less. On the base material sheet, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. A conductive polymer (Seplujida (registered trademark) OC-AE manufactured by Shin-Etsu Polymer) was applied to H2 at 150 nm and heat-treated at 120 ° C. for 2 minutes to form a transparent electrode to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Example 3)
A thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., ZF) was used as a substrate sheet having a retardation of 10 nm or less. On the base material sheet, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. A transparent electrode having excellent crystallinity was formed by sputtering IZO on H 2 at 150 ° C. and further performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

Example 4
A thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., ZF) was used as a substrate sheet having a retardation of 10 nm or less. On the said base material sheet, 1 micrometer hard coat layer forming composition H1 was apply | coated to 1 micrometer, H3 was applied to the other surface 1 micrometer, and it hardened | cured by ultraviolet irradiation. A transparent electrode having excellent crystallinity was formed by sputtering ITO on H3 at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.
(Example 5)
As a base sheet having a retardation of 140 nm, a product name “Zeonor Film (registered trademark) ZD14” (hereinafter abbreviated as ZD) having a thickness of 60 μm manufactured by Nippon Zeon Co., Ltd. was used. On the base material sheet, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. A transparent electrode excellent in crystallinity was formed by sputtering ITO on H2 at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.
(Example 6)
As a substrate sheet having a retardation of 10 nm or less, a thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., trade name ZF) was used. On the base material, the hard coat layer forming composition H2 was applied to both sides of 1 μm and cured by ultraviolet irradiation. A transparent electrode having excellent crystallinity was formed by sputtering ITO on one side at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.
(Example 7)
As a substrate sheet having a retardation of 10 nm or less, a thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., trade name ZF) was used. On the said base material sheet, the hard-coat layer forming composition H2 was apply | coated to 1 micrometer both surfaces, and it hardened | cured by ultraviolet irradiation. By screen printing on one side, a conductive polymer (Sepetsu Gida (registered trademark) made by Shin-Etsu Polymer) with a thickness of 150 nm, a stripe with a width of 1 mm and an interval of 5 mm, and heat treatment at 120 ° C. for 2 minutes to form a transparent electrode The optical sheet for touch panels was obtained. On the other side, a conductive polymer stripe was formed in a similar manner so as to go straight to obtain a laminated film for a touch panel. The results are shown in Table 1.
(Example 8)
A thickness of 60 μm (manufactured by Nippon Zeon Co., Ltd., trade name ZD) was used as a base sheet having a retardation of 140 nm. On the base sheet, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. Transparent by conducting a heat treatment at 120 ° C for 2 minutes by creating stripes with a width of 1 mm and a spacing of 5 mm with a conductive polymer (Sepuru Gida (registered commercial method) made by Shin-Etsu Polymer) on the H2 surface by screen printing. An electrode was formed to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Comparative Example 1)
A thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., ZF) was used as a substrate sheet having a retardation of 10 nm or less. On the said base material sheet, the hard-coat layer forming composition H4 was apply | coated to 1 micrometer both surfaces, and it hardened | cured by ultraviolet irradiation. A transparent electrode having excellent crystallinity was formed by sputtering ITO on one side at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Comparative Example 2)
A polyethylene terephthalate (PET) film (Toyobo Cosmo Shine A-4300) having a thickness of 100 μm was used as a base sheet. On the said base material sheet, the hard-coat layer forming composition H4 was apply | coated to 1 micrometer both surfaces, and it hardened | cured by ultraviolet irradiation. A transparent electrode having excellent crystallinity was formed by sputtering ITO on one side at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Comparative Example 3)
As a base sheet having a retardation of 140 nm, a polycarbonate (Iupilon (registered trademark)) film having a thickness of 80 μm was used. On the base material, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H2 was applied on the other side, and cured by ultraviolet irradiation. A transparent electrode excellent in crystallinity was formed by sputtering ITO on H2 at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

(Comparative Example 4)
A thickness of 100 μm (manufactured by Nippon Zeon Co., Ltd., ZF) was used as a substrate sheet having a retardation of 10 nm or less. On the base material, 1 μm of the hard coat layer forming composition H1 was applied on one side, 1 μm of H5 was applied on the other side, and cured by ultraviolet irradiation. A transparent electrode excellent in crystallinity was formed by sputtering ITO on H5 at 150 ° C. and performing heat treatment at 150 ° C. for 1 hour to obtain a laminated film for a touch panel. The results are shown in Table 1.

By making 1 to 3 types of particles, blocking prevention, haze of 1% or less, and good adhesion were confirmed.

DESCRIPTION OF SYMBOLS 1 ... Laminated film 11 for touchscreens of this invention ... 1st hard coat layer 12 ... Base material sheet 13 ... 2nd hard coat layer 14 ... ..Conductive film

Claims (7)

The base sheet is made of a thermoplastic norbornene resin, the first hard coat layer is laminated on the surface, and the second hard coat layer is laminated on the opposite base sheet surface,
The substrate sheet has an in-plane retardation of 10 nm or less and a thickness direction retardation of 10 nm or less, or an in-plane retardation of 120 to 150 nm, and a thickness direction retardation of 60 to 225 nm,
The first hard coat layer and the second hard coat layer contain fine particles having a primary average particle diameter (D50) of 500 nm or less, or two or three kinds of particles having different primary particle diameters of 500 nm or less. Laminated film.   2. The laminated film according to claim 1, wherein the film formed by laminating the first hard coat layer and the second hard coat layer has a haze of 1% or less.   The laminated film according to claim 1 or 2, wherein a difference in contact angle in distilled water between the first hard coat layer and / or the second hard coat layer and the base sheet is 10 ° or more.   A laminated film for a touch panel, wherein a conductive film is further laminated on the first hard coat layer and / or the second hard coat layer of the laminated film according to claim 1.   The laminated film for a touch panel according to claim 4, wherein the conductive film is made of a conductive polymer containing ITO, IZO, or polythiophene.   The laminated film for a touch panel according to claim 4 or 5, wherein the conductive film is a uniform plane or patterned.   The laminated film for a touch panel according to any one of claims 4 to 6, wherein the fine particles comprise a hard coat layer which is the same component as the silicon oxide and / or the conductive layer.

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