JP2013109682A - Manufacturing method of transparent conductive laminate and capacitive touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparent conductive laminate in which differently-shaped fine patterns can be simultaneously formed on both surfaces of a substrate through a short manufacturing process and the fine patterns can be easily aligned, and to provide a manufacturing method of the transparent conductive laminate, and a capacitive touch panel.SOLUTION: A transparent conductive laminate 10 includes: a transparent substrate layer 1; and a first transparent conductive layer 3a having first conductive pattern areas 4a and first non-conductive pattern areas 4b and a second transparent conductive layer 3b having the first conductive pattern areas 4a and the first non-conductive pattern areas 4b, the conductive layers formed on both surfaces of the transparent substrate layer 1. At least one layer formed between the first transparent conductive layer 3a and the second transparent conductive layer 3b has a function to absorb light.

Description

  The present invention relates to a method for producing a transparent conductive laminate and a capacitive touch panel using the transparent conductive laminate produced by the production method.

  In recent years, a transparent touch panel is attached as an input device on the display of various electronic devices. Examples of the touch panel system include a resistance film type and a capacitance type. In particular, the capacitance type can be multi-touched and is widely used for mobile devices and the like.

  A capacitive touch panel uses a transparent conductive layer on which a pattern is formed. As a method of forming a pattern on the transparent conductive layer, for example, there is a photolithography method in which a pattern is formed using a resist as in Patent Documents 1 to 3. As another method, as in Patent Document 4, an indium compound having a functional group or site that reacts with light and a tin compound having a similar functional group or site are used as the conductive film forming composition, and pattern exposure is performed. There are a method of performing pattern formation, a method of performing pattern formation by laser light, and the like as disclosed in Patent Document 5.

  In addition, since the capacitive touch panel is used on a display, there is a problem that visibility is lowered when the pattern shape of the transparent conductive layer is conspicuous. For this reason, a transparent conductive laminate for a touch panel having an increased transmittance by forming an optical adjustment layer in addition to the transparent conductive layer as in Patent Document 6 has been proposed so as not to deteriorate the image quality of the display.

JP-A-1-197911 JP-A-2-109205 JP-A-2-309510 Japanese Patent Laid-Open No. 9-142848 JP 2008-140130 A Japanese Patent Laid-Open No. 11-286066

  However, the photolithography methods as described in Patent Documents 1 to 3 often require many manufacturing steps. In particular, when a transparent conductive layer is provided on both surfaces of a substrate to form a pattern, the manufacturing process becomes complicated because steps such as resist coating, exposure, and development are performed on each side. In addition, in order to solve the problem of the decrease in visibility, when an optical adjustment layer is formed in addition to the transparent conductive layer as in Patent Document 6, it is necessary to increase the number of manufacturing processes, which further complicates the manufacturing process. become.

  In addition, a method such as Patent Document 4 or 5 can use a resist without using a resist and can shorten the manufacturing process. However, in the method of Patent Document 4, a transparent conductive layer is provided on both sides of a substrate to form a pattern. When forming the pattern, it is difficult to align the positions of the patterns formed on both sides of the substrate. In particular, when a fine pattern is to be formed on both sides of the substrate, it is a big problem to align the position of the pattern. On the other hand, in the method of Patent Document 5, the same pattern can be formed on both surfaces of the substrate by laser light, but there is a problem in that it cannot be applied when different patterns are formed on both surfaces of the substrate.

  The present invention has been made in view of the problems of the prior art, and the object thereof is to form different shapes on both sides of a substrate in a short manufacturing process even if a method of forming a pattern on a transparent conductive layer using a resist is used. A transparent conductive laminate that can form a pattern simultaneously, is easy to align even if the pattern formed on both sides of the substrate is fine, and is advantageous in making the pattern shape inconspicuous, and It is in providing the manufacturing method and a capacitive touch panel.

  As means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that at least a first transparent conductive layer and a second transparent conductive layer are formed on both surfaces of the transparent substrate layer, and the first Applying a resist to the surface of the transparent conductive layer and the second transparent conductive layer; a light source and a mask for forming a pattern on the first transparent conductive layer; and forming a pattern on the second transparent conductive layer. A light source and a mask for forming are sequentially arranged from the light source side, and the resist applied to the surface of the first transparent conductive layer and the resist applied to the surface of the second transparent conductive layer are simultaneously provided. A step of exposing, a step of developing the exposed resist, a step of etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist, and a step of peeling the resist , A method for producing a transparent conductive laminate, wherein at least one layer formed between the first transparent conductive layer and the second transparent conductive layer is a layer that absorbs light. is there.

  The invention according to claim 2 is characterized in that the transparent substrate layer is a layer that absorbs light, and the transparent substrate layer contains an ultraviolet absorber or a resin having an ultraviolet absorbing function. It is a manufacturing method of the transparent conductive laminated body of description.

  The invention according to claim 3 forms a resin layer on both surfaces of the transparent substrate layer, and forms the first transparent conductive layer and the second transparent conductive layer on the surface of the resin layer. The transparent conductive laminate according to claim 1, further comprising a step, wherein the resin layer is a layer that absorbs light, and the resin layer includes an ultraviolet absorber or a resin having an ultraviolet absorption function. It is a manufacturing method.

  According to a fourth aspect of the present invention, at least a first transparent conductive layer is formed on one side of the first transparent substrate layer, and at least a second transparent conductive layer is formed on one side of the second transparent substrate layer. Forming the first transparent conductive layer and the second transparent conductive layer outside, and bonding the first transparent substrate layer and the second transparent substrate layer together with an adhesive layer; Applying a resist to the surfaces of the first transparent conductive layer and the second transparent conductive layer; a light source and a mask for forming a pattern on the first transparent conductive layer; and the second transparent conductive layer. A light source and a mask for forming a pattern on the layer are sequentially arranged from the light source side, and the resist applied to the surface of the first transparent conductive layer and the surface applied to the surface of the second transparent conductive layer The process of exposing the resist simultaneously and before exposure A step of developing a resist, a step of etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist, and a step of peeling the resist. The method for producing a transparent conductive laminate, wherein at least one layer formed between the transparent conductive layer and the second transparent conductive layer is a layer that absorbs light.

  The invention described in claim 5 is characterized in that the adhesive layer is a layer that absorbs light, and the adhesive layer contains an ultraviolet absorber or a resin having an ultraviolet absorbing function. It is a manufacturing method of a transparent conductive laminated body.

  The invention according to claim 6 is the transparent conductive laminate according to any one of claims 1 to 5, wherein the resist is a resist sensitive to light having a wavelength of 370 nm or less. It is a manufacturing method.

  The invention according to claim 7 is the transparent conductive laminate according to any one of claims 1 to 6, wherein a light absorption region of the light absorbing layer is 370 nm or less. It is a manufacturing method.

  The invention according to claim 8 is characterized in that the process from the step of forming the transparent conductive layer on the transparent substrate layer to the step of peeling off the resist is performed by a roll-to-roll method. It is a manufacturing method of the transparent conductive laminated body as described in any one.

  Moreover, invention of Claim 9 is an electrostatic capacitance type touch panel using the transparent conductive laminated body manufactured by the manufacturing method as described in any one of Claims 1-8.

  According to the present invention, the transparent substrate layer, the resin layer, or the adhesive layer is a layer that absorbs light, so that different patterns can be simultaneously formed on both sides of the transparent conductive layer formed on both sides of the transparent substrate layer. , The reflection of each other's pattern can be prevented. Further, since patterns having different shapes can be simultaneously formed on both surfaces of the transparent substrate layer, alignment can be easily performed even if the pattern is fine. Furthermore, since a fine pattern can be accurately formed on both surfaces of the transparent substrate layer, the pattern shape can be made inconspicuous by the fine pattern, and as a result, a highly conductive transparent conductive laminate can be obtained. .

It is explanatory drawing of the example 1 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 2 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 3 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 4 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 5 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the cross-sectional example 6 of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 7 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example 8 of a cross section of the transparent conductive laminated body of this invention. It is explanatory drawing of the example of a pattern (X coordinate) of a transparent conductive layer. It is explanatory drawing of the example of a pattern (Y coordinate) of a transparent conductive layer. It is explanatory drawing of the positional relationship of the X coordinate of a pattern example of a transparent conductive layer, and a Y coordinate. It is explanatory drawing of the example of an exposure process of the transparent conductive laminated body of this invention. It is explanatory drawing of the pattern formation process example of the transparent conductive laminated body of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and modifications such as design changes can be made based on the knowledge of those skilled in the art, and such modifications have been added. Embodiments are also included in the scope of the present invention.

  FIG. 1 is an explanatory view of a cross-sectional example 1 of the transparent conductive laminate of the present invention. The transparent conductive laminate 10 includes a first transparent conductive layer 3a formed with conductive pattern regions 4a and non-conductive pattern regions 4b provided on both surfaces of the transparent substrate 1, and conductive pattern regions 4a and non-conductive layers. And a second transparent conductive layer 3b in which a pattern region 4b is formed. Here, the conductive pattern region refers to a portion having conductivity in the transparent conductive layer, and the non-conductive pattern region is a conductivity excluding a portion having conductivity in the transparent conductive layer. The part that does not have.

  FIG. 2 is an explanatory view of a cross-sectional example 2 of the transparent conductive laminate of the present invention. As shown in FIG. 2, between the transparent substrate 1 and the first transparent conductive layer 3a and between the transparent substrate 1 and the second transparent conductive layer 3b of the transparent conductive laminate 10 shown in FIG. The optical adjustment layers 2a and 2b may be provided. In another embodiment, an optical adjustment layer may be provided only between either the transparent substrate 1 and the first transparent conductive layer 3a or between the transparent substrate 1 and the second transparent conductive layer 3b. Good.

  FIG. 3 is an explanatory view of a cross-sectional example 3 of the transparent conductive laminate of the present invention. The transparent conductive laminate 10 includes a first transparent conductive layer 3a formed with conductive pattern regions 4a and non-conductive pattern regions 4b provided on both surfaces of the transparent substrate 1, and conductive pattern regions 4a and non-conductive layers. The second transparent conductive layer 3b in which the pattern region 4b is formed, and the resin layers provided between the transparent substrate 1 and the first transparent conductive layer 3a and between the transparent substrate 1 and the second transparent conductive layer 3b, respectively. 5a and 5b. As other embodiments, a resin layer may be provided only between either the transparent substrate 1 and the first transparent conductive layer 3a or between the transparent substrate 1 and the second transparent conductive layer 3b. .

  FIG. 4 is an explanatory view of a cross-sectional example 4 of the transparent conductive laminate of the present invention. As shown in FIG. 4, between the resin layer 5a and the first transparent conductive layer 3a and between the resin layer 5b and the second transparent conductive layer 3b of the transparent conductive laminate 10 shown in FIG. The optical adjustment layers 2a and 2b may be provided. In another embodiment, an optical adjustment layer may be provided only between the resin layer 5a and the first transparent conductive layer 3a or between the resin layer 5b and the second transparent conductive layer 3b. Good. Further, an optical adjustment layer may be provided between the transparent substrate 1 and the resin layer 5a or between the transparent substrate 1 and the resin layer 5b.

  FIG. 5 is an explanatory view of a cross-sectional example 5 of the transparent conductive laminate of the present invention. The transparent conductive laminate 10 includes a first transparent conductive layer 3a having a conductive pattern region 4a and a nonconductive pattern region 4b provided on one side of the first transparent substrate 1a, and a second transparent substrate 1b. The second transparent conductive layer 3b formed with the conductive pattern region 4a and the non-conductive pattern region 4b provided on one side of the first, the first transparent conductive layer 3a and the second transparent conductive layer 3b are arranged outside, It is comprised from the adhesion layer 6 provided between the 1st transparent substrate 1a and the 2nd transparent substrate 1b.

  FIG. 6 is an explanatory view of a cross-sectional example 6 of the transparent conductive laminate of the present invention. Like FIG. 6, between the 1st transparent substrate 1a and the 1st transparent conductive layer 3a of the transparent conductive laminated body 10 shown in FIG. 5, and the 2nd transparent substrate 1b and the 2nd transparent conductive layer 3b. Between these, optical adjustment layers 2a and 2b may be provided, respectively. As other embodiments, optically only between either the first transparent substrate 1a and the first transparent conductive layer 3a or between the second transparent substrate 1b and the second transparent conductive layer 3b. An adjustment layer may be provided.

  FIG. 7 is an explanatory view of a cross-sectional example 7 of the transparent conductive laminate of the present invention. The transparent conductive laminate 10 includes a resin layer 5a between the first transparent substrate 1a and the first transparent conductive layer 3a and between the second transparent substrate 1b and the second transparent conductive layer 3b, respectively. 5b may be provided. In other embodiments, the resin is provided only between one of the first transparent substrate 1a and the first transparent conductive layer 3a or between the second transparent substrate 1b and the second transparent conductive layer 3b. A layer may be provided.

  FIG. 8 is an explanatory view of a cross-sectional example 8 of the transparent conductive laminate of the present invention. As shown in FIG. 8, between the resin layer 5a and the first transparent conductive layer 3a and between the resin layer 5b and the second transparent conductive layer 3b of the transparent conductive laminate 10 shown in FIG. The optical adjustment layers 2a and 2b may be provided. In another embodiment, an optical adjustment layer may be provided only between the resin layer 5a and the first transparent conductive layer 3a or between the resin layer 5b and the second transparent conductive layer 3b. Good. Further, an optical adjustment layer may be provided between the first transparent substrate 1a and the resin layer 5a or between the second transparent substrate 1b and the resin layer 5b.

  In addition to glass, the transparent substrate layers 1, 1a and 1b used in the present invention are plastic films made of resin. The plastic film is not particularly limited as long as it has sufficient strength in the film-forming process and the subsequent process and has good surface smoothness. For example, polyethylene terephthalate film, polybutylene terephthalate film, polyethylene naphthalate film, polycarbonate Examples include films, polyethersulfone films, polysulfone films, polyarylate films, cyclic polyolefin films, polyimide films, and the like. The thickness is about 10 μm or more and 200 μm or less in consideration of the thinning of the member and the flexibility of the base material.

  The transparent substrate layers 1, 1a, and 1b used in the present invention preferably absorb light. When a pattern is formed on the transparent conductive layers on both sides of the transparent substrate layer 1 by absorbing light, the light that has not been absorbed by the resist among the light irradiated from one side of the transparent substrate layer 1 is transparent. This is because it can be absorbed by the substrate layer 1 and light can be prevented from reaching the resist on the other surface side of the transparent substrate layer 1. In particular, when different patterns are simultaneously formed on both surfaces of the transparent substrate layer 1, only the resist on one surface side can be exposed, so that the pattern on one surface is prevented from overlapping with the pattern on the other surface. Can do. For the same reason, it is preferable that the transparent substrate layers 1a and 1b also absorb light.

  As described above, the transparent substrate layers 1, 1a, and 1b preferably absorb light for exposing the resist. The light used for exposing the resist varies depending on the type of resist or the type of light source, but light having a wavelength in the ultraviolet region (about 200 nm to 360 nm) and a wavelength in the visible region (about 360 nm to 780 nm) is often used. Thus, the transparent substrate layer 1 preferably absorbs light in these regions. In consideration of practicality, the transparent substrate layer 1 preferably absorbs light of 370 nm or less in the ultraviolet region.

  Examples of the light absorbing material used to absorb ultraviolet light include an ultraviolet absorber and a resin having an ultraviolet absorbing function, and an ultraviolet absorber is added to the transparent substrate layer or a resin constituting the transparent substrate layer. A resin having an ultraviolet absorbing function can be copolymerized.

  Examples of the ultraviolet absorber contained in the transparent substrate layers 1, 1a, and 1b include benzophenone, benzotriazole, benzoate, salicylate, triazine, and cyanoacrylate. Specifically, for example, as the benzotriazole-based ultraviolet absorber, 2- (2H-benzotriazol-2-yl) -p-cresol, 2- (2H-benzotriazol-2-yl) -4-6-bis (1-methyl-1-phenylethyl) phenol, 2- [5-chloro (2H) -benzotriazol-2-yl] -4-methyl-6- (tert-butyl) phenol, 2- (2H-benzotriazole -Yl) -4,6-di-tert-pentylphenol, 2- (2H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol and mixtures thereof, Examples include modified products, polymers, and derivatives. Further, for example, as a triazine ultraviolet absorber, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4- [ (2-hydroxy-3-dodecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [4-[(2 -Hydroxy-3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4dimethylphenyl) -1,3,5-triazine, 2,4-bis (2,4- Examples thereof include dimethylphenyl) -6- (2-hydroxy-4-iso-octyloxyphenyl) -s-triazine, mixtures thereof, modified products, polymers, and derivatives. These may be used alone or in combination.

  In addition, the resin having an ultraviolet absorbing function includes the above-mentioned non-reactive ultraviolet absorbers such as benzophenone, benzotriazole, benzoate, salicylate, triazine, cyanoacrylate, vinyl group, acryloyl group, A functional group having a polymerizable double bond such as a methacryloyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group is introduced. These resins and the resin contained in the transparent substrate layers 1, 1a and 1b can be copolymerized and used as a transparent substrate layer having an ultraviolet absorbing function.

  The light absorbing materials mentioned above may be used not only alone but also in combination. For example, unnecessary light can be absorbed in a wide wavelength region by using a plurality of light absorbing materials having different wavelengths of light that can be absorbed.

  The content of the light-absorbing material is not particularly limited as long as light that has not been absorbed by the resist on one surface of the transparent substrate layers 1, 1a, and 1b can be prevented from reaching the resist on the other surface. It is preferable to contain 0.01 weight% or more and 20 weight% or less with respect to resin which comprises 1a and 1b. If it is smaller than the lower limit, it is not preferable because unnecessary light cannot be sufficiently absorbed. Moreover, when exceeding an upper limit, transparency of the transparent substrate layers 1, 1a, and 1b will fall, and it is unpreferable on an external appearance.

  As materials contained in the transparent substrate layers 1, 1a and 1b, in addition to the above materials, various known additives and stabilizers such as antistatic agents, plasticizers, lubricants, and easy-adhesive agents are used. Also good. In order to improve adhesion with each layer, corona treatment, low temperature plasma treatment, ion bombardment treatment, chemical treatment, etc. may be performed as pretreatment.

  The resin layers 5a and 5b used in the present invention are provided in order to give the transparent conductive laminate 10 mechanical strength. Although it does not specifically limit as resin used, Resin which has transparency, moderate hardness, and mechanical strength is preferable. Specifically, a photocurable resin such as a monomer or a crosslinkable oligomer having a tri- or higher functional acrylate that can be expected to be three-dimensionally crosslinked as a main component is preferable.

  Trifunctional or higher acrylate monomers include trimethylolpropane triacrylate, isocyanuric acid EO-modified triacrylate, pentaerythritol triacrylate, dipentaerythritol triacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate Ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, polyester acrylate and the like are preferable. Particularly preferred are isocyanuric acid EO-modified triacrylate and polyester acrylate. These may be used alone or in combination of two or more. In addition to these tri- or higher functional acrylates, so-called acrylic resins such as epoxy acrylate, urethane acrylate, and polyol acrylate can be used in combination.

  As the crosslinkable oligomer, acrylic oligomers such as polyester (meth) acrylate, polyether (meth) acrylate, polyurethane (meth) acrylate, epoxy (meth) acrylate, and silicone (meth) acrylate are preferable. Specific examples include polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, bisphenol A type epoxy acrylate, polyurethane diacrylate, and cresol novolac type epoxy (meth) acrylate.

  The resin layers 5a and 5b may further contain additives such as particles and a photopolymerization initiator.

  Examples of the particles to be added include organic or inorganic particles, but it is preferable to use organic particles in consideration of transparency. Examples of the organic particles include particles made of acrylic resin, polystyrene resin, polyester resin, polyolefin resin, polyamide resin, polycarbonate resin, polyurethane resin, silicone resin, and fluorine resin.

  The average particle diameter of the particles varies depending on the thickness of the resin layers 5a and 5b, but for reasons of appearance such as haze, the lower limit is 2 μm or more, more preferably 5 μm or more, and the upper limit is 30 μm or less, preferably 15 μm or less. Is used. Further, for the same reason, the particle content is preferably 0.5% by weight or more and 5% by weight or less based on the resin.

  When a photopolymerization initiator is added, radical generating photopolymerization initiators include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyl methyl ketal, acetophenone, 2, 2 , -Dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, and other acetophenones, methylanthraquinone, 2-ethylanthraquinone, 2-amylanthraquinone and other anthraquinones, thioxanthone, 2,4-diethylthioxanthone, 2, 4 -Thioxanthones such as diisopropylthioxanthone, ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal, benzophenone, 4,4-bismeth Le benzophenones such aminobenzophenone and azo compounds, and the like. These can be used alone or as a mixture of two or more thereof, and further, tertiary amines such as triethanolamine and methyldiethanolamine, benzoic acid derivatives such as 2-dimethylaminoethylbenzoic acid and ethyl 4-dimethylaminobenzoate, etc. It can be used in combination with a photoinitiator aid or the like.

  The addition amount of the photopolymerization initiator is 0.1% by weight or more and 5% by weight or less, preferably 0.5% by weight or more and 3% by weight or less with respect to the main resin. Less than the lower limit is not preferable because the hard coat layer is insufficiently cured. Moreover, when exceeding an upper limit, since yellowing of a hard-coat layer is produced or a weather resistance falls, it is unpreferable. The light used for curing the photocurable resin is ultraviolet rays, electron beams, or gamma rays, and in the case of electron beams or gamma rays, it is not always necessary to contain a photopolymerization initiator or a photoinitiating aid. As these radiation sources, high pressure mercury lamps, xenon lamps, metal halide lamps, accelerated electrons, and the like can be used.

  Moreover, the thickness of the resin layers 5a and 5b is not particularly limited, but a range of 0.5 μm or more and 15 μm or less is preferable. Moreover, it is more preferable that the refractive index is the same as or close to that of the transparent substrate layer 1, and it is preferably about 1.45 or more and 1.75 or less.

  The resin layers 5a and 5b are formed by dissolving a resin as a main component in a solvent, a die coater, a curtain flow coater, a roll coater, a reverse roll coater, a gravure coater, a knife coater, a bar coater, a spin coater, and a micro gravure. It is formed by a known coating method such as a coater.

  The solvent is not particularly limited as long as it dissolves the main component resin and the like. Specifically, as a solvent, ethanol, isopropyl alcohol, isobutyl alcohol, benzene, toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, n-butyl acetate, isoamyl acetate, ethyl lactate, methyl cellosolve, ethyl cellosolve, Examples include butyl cellosolve, methyl cellosolve acetate, and propylene glycol monomethyl ether acetate. These solvents may be used alone or in combination of two or more.

  The resin layers 5a and 5b of the present invention preferably absorb light for exposing the resist, particularly ultraviolet light, for the same reason as the transparent substrate layers 1, 1a and 1b. Examples of the resin layer that absorbs ultraviolet light include a resin layer containing an ultraviolet absorber and a resin layer containing a resin having an ultraviolet absorbing function. Specific examples of the light absorbing material include a transparent substrate layer. Examples thereof include the same materials as those contained in 1, 1a and 1b. Further, the content of the light absorbing material is preferably contained in the same degree as the content in the transparent substrate layers 1, 1a, and 1b.

  The resin layers 5a and 5b may have a function of absorbing light alone, or may have a function of absorbing light together with the transparent substrate layers 1, 1a and 1b. By having both the resin layers 5a and 5b and the transparent substrate layers 1, 1a and 1b have a function of absorbing light, the light which has not been absorbed by the resist on one surface of the transparent substrate layer can be sufficiently absorbed, It is possible to further prevent the pattern on one surface from overlapping the pattern on the other surface.

  Further, both the resin layers 5a and 5b and the transparent substrate layers 1, 1a and 1b have a function of absorbing light, and the light layers which can be absorbed by the resin layers 5a and 5b and the transparent substrate layers 1, 1a and 1b. The wavelength may be changed. Thereby, when a light source having a wide wavelength region is used, unnecessary light can be absorbed in a wide wavelength region.

  The pressure-sensitive adhesive layer 6 of the present invention is a layer for bonding the first transparent substrate 1a and the second transparent substrate 1b. Examples of the resin used for the adhesive layer 6 include acrylic resins, silicone resins, and rubber resins, and it is preferable to use a resin excellent in cushioning properties and transparency.

  The pressure-sensitive adhesive layer 6 of the present invention preferably absorbs light for exposing the resist, particularly ultraviolet light, for the same reason as the transparent substrate layers 1, 1a and 1b. Examples of the resin layer that absorbs ultraviolet light include a resin layer containing an ultraviolet absorber and a resin layer containing a resin having an ultraviolet absorbing function. Specific examples of the light absorbing material include a transparent substrate layer. Examples thereof include the same materials as those contained in 1, 1a and 1b. Further, the content of the light absorbing material is preferably contained in the same degree as the content in the transparent substrate layers 1, 1a, and 1b.

  The adhesive layer 6 may have a function of absorbing light alone, or may have a function of absorbing light together with the transparent substrate layers 1, 1a and 1b or the resin layers 5a and 5b. By having the function of absorbing light together with the transparent substrate layers 1, 1 a and 1 b or the resin layers 5 a, 5 b, the light that has not been absorbed by the resist on one surface of the transparent substrate layer can be sufficiently absorbed, It is possible to further prevent the surface pattern from overlapping with the pattern of the other surface.

  The adhesive layer 6, the transparent substrate layers 1, 1a and 1b and the resin layers 5a and 5b all have a function of absorbing light, and the adhesive layer 6, the transparent substrate layers 1, 1a and 1b and the resin layer 5a, You may change the wavelength of the light which 5b can mutually absorb. Thereby, when a light source having a wide wavelength region is used, unnecessary light can be absorbed in a wide wavelength region.

  The optical adjustment layers 2a and 2b have a function of making the pattern formed on the first transparent conductive layer 3a and the second transparent conductive layer 3b inconspicuous, and are layers for improving visibility. When an inorganic compound is used as the optical adjustment layers 2a and 2b, materials such as oxides, sulfides, fluorides, and nitrides can be used. The thin film made of the inorganic compound has a different refractive index depending on the material, and the optical characteristics can be adjusted by forming a thin film having a different refractive index with a specific film thickness. The number of optical functional layers may be a plurality of layers depending on the target optical characteristics.

  Materials having a low refractive index include magnesium oxide (1.6), silicon dioxide (1.5), magnesium fluoride (1.4), calcium fluoride (1.3 to 1.4), cerium fluoride ( 1.6), aluminum fluoride (1.3), and the like. Moreover, as a material with a high refractive index, titanium oxide (2.4), zirconium oxide (2.4), zinc sulfide (2.3), tantalum oxide (2.1), zinc oxide (2.1), Examples include indium oxide (2.0), niobium oxide (2.3), and tantalum oxide (2.2). However, the numerical value in the parenthesis represents the refractive index.

  The first transparent conductive layer 3a and the second transparent conductive layer 3b are made of indium oxide, zinc oxide, tin oxide, or two or three kinds of mixed oxides thereof, and other additives. Examples include materials added, but various materials can be used depending on the purpose and application, and are not particularly limited. At present, the most reliable and proven material is indium tin oxide (ITO).

  When indium tin oxide (ITO), which is the most common transparent conductive film, is used as the first transparent conductive layer 3a and the second transparent conductive layer 3b, the content ratio of tin oxide doped in indium oxide is required for the device. Select an arbitrary ratio according to the specifications to be used. For example, when the transparent substrate is a plastic film, the sputtering target material used for crystallizing the thin film for the purpose of increasing the mechanical strength preferably has a tin oxide content of less than 10% by weight. In order to impart the properties, the content ratio of tin oxide is preferably 10% by weight or more. Moreover, when low resistance is calculated | required by a thin film, the content rate of a tin oxide has the preferable range of 3 to 20 weight%.

  The optical adjustment layers 2a, 2b, the first transparent conductive layer 3a, and the second transparent conductive layer 3b may be produced by any film forming method as long as the film thickness can be controlled. The law is excellent. For this, a vacuum vapor deposition method, a physical vapor deposition method such as sputtering, or a chemical vapor deposition method such as a CVD method can be used. In particular, in order to form a thin film having a uniform film quality over a large area, a sputtering method in which the process is stable and the thin film becomes dense is preferable.

  The first transparent conductive layer 3a and the second transparent conductive layer 3b are subjected to X coordinate and Y coordinate patterns as shown in FIG. As shown in FIG. 9 or FIG. 10, the pattern to be formed includes a conductive pattern region 4a represented in black and a non-conductive pattern region 4b represented in white. Further, although not shown, the conductive pattern region 4a is connected to a circuit capable of detecting a current change. When a human finger or the like approaches the conductive pattern region 4a that is the detection electrode, the entire capacitance changes, so that a current flows through the circuit, and the contact position can be determined. The two-dimensional position information can be obtained by providing the patterns shown in FIGS. 9 and 10 on both sides of the transparent substrate layer, combining the X-coordinate and Y-coordinate patterns as shown in FIG. . The black pattern in FIG. 11 is the conductive pattern region 4a formed on the front side of the transparent substrate layer, and the gray pattern is the conductive pattern region 4a formed on the back side of the transparent substrate layer. .

  The pattern shape of the first transparent conductive layer 3a and the second transparent conductive layer 3b includes a mesh type pattern in addition to the diamond type pattern as shown in FIG. 9 and FIG. In order to read, it is necessary to form a pattern as fine as possible and to accurately align the patterns provided on both surfaces of the transparent substrate layer.

  As a pattern formation method of the first transparent conductive layer 3a and the second transparent conductive layer 3b, a resist is applied on the first transparent conductive layer 3a and the second transparent conductive layer 3b, and the pattern is exposed and developed. Examples thereof include a photolithography method in which the transparent conductive layer is chemically dissolved after formation, a method of vaporizing by a chemical reaction in vacuum, a method of sublimating the transparent conductive layer with a laser, and the like. The pattern forming method can be appropriately selected depending on the shape and accuracy of the pattern. However, in order to simultaneously form different patterns for the first transparent conductive layer 3a and the second transparent conductive layer 3b, a photolithography method is used. Is preferred.

  The exposure process by photolithography of the transparent conductive laminate of the present invention is shown in FIG. 12, taking the transparent conductive laminate 10 shown in FIG. 1 as an example. The method for forming the conductive pattern region 4a and the non-conductive pattern region 4b formed in the first transparent conductive layer 3a and the second transparent conductive layer 3b of the transparent conductive laminate 10 is as follows. A resist 7a is applied to the surface of the layer 3a, and a resist 7b is applied to the surface of the second transparent conductive layer 3b. Next, a light source 8a for forming a pattern on the first transparent conductive layer 3a and a mask 9a are sequentially arranged from the light source 8a side, and a light source 8b for forming a pattern on the second transparent conductive layer 3b. And the mask 9b are sequentially arranged from the light source 8b side. Thereafter, the resists 7a and 7b are simultaneously exposed to light from the light source 8a and the light source 8b.

  At this time, since the transparent substrate 1 has a function of absorbing light having a wavelength of 370 nm or less by using a chemically amplified resist that reacts only in the wavelength band of 370 nm or less, the resists 7a and 7b are not absorbed by the resist 7a. It is possible to prevent the resist 7b applied to the surface of the second transparent conductive layer 3b from being exposed by absorbing the absorbed light by the transparent substrate layer 1. On the contrary, the light that has not been absorbed by the resist 7b is absorbed by the transparent substrate layer 1, and the resist 7a applied to the surface of the first transparent conductive layer 3a can be prevented from being exposed, and the wavelength of the light source can be specified. An optical filter for cutting the wavelength band becomes unnecessary, and the light source light quantity is not reduced. Note that the wavelength of i-line of a high-pressure mercury lamp, which is a commonly used light source, has a wavelength of 365 nm, which is advantageous because only one surface can be exposed at this wavelength.

  Moreover, since the exposure process by the photolithography of the transparent conductive laminated body of this invention can form a pattern simultaneously on both surfaces of the transparent substrate 1, it can align the pattern formed in both surfaces easily. . When the patterns on both sides of the transparent substrate 1 are performed one side at a time, after the pattern is formed on one side, the pattern must be formed on the other side according to the position of the pattern, and the position adjustment is difficult. In particular, when a fine pattern is formed in order to accurately read the two-dimensional position information or to improve the visibility of the pattern, it is not possible to perform alignment with high accuracy by pattern formation on each side.

  For example, when the transparent substrate layers 1, 1a and 1b, the resin layers 5a, 5b or the adhesive layer 6 contain an ultraviolet absorber, the resist on one surface of the transparent substrate layer is exposed. The light that is not absorbed by the resist on one side of the transparent substrate layer is absorbed by the ultraviolet absorber contained in the transparent substrate layers 1, 1 a and 1 b, the resin layers 5 a, 5 b or the adhesive layer 6, and on the other side Prevent the resist from being exposed.

  The masks 9a and 9b are masks for forming a pattern on the resists 7a and 7b. Specifically, the masks 9a and 9b are used to form the pattern shown in FIG.

  Similarly, in the transparent conductive laminate of the present invention shown in FIGS. 2 to 8, the conductive pattern region 4a and the non-conductive layer formed on the first transparent conductive layer 3a and the second transparent conductive layer 3b by the above-described exposure process. The conductive pattern region 4b can be formed.

  Each process of the pattern formation method by the photolithography of the transparent conductive laminated body of this invention is shown in FIG. FIG. 13 shows each process of manufacturing the transparent conductive laminate 10 of FIG. 1 as an example. First, the transparent substrate 1 is prepared (step (a)), and the first transparent conductive layer 3a and the second transparent conductive layer 3b are formed on both surfaces thereof (step (b)). Further, resists 7a and 7b are applied to the surfaces of the first transparent conductive layer 3a and the second transparent conductive layer 3b, respectively (step (c)). Thereafter, the resists 7a and 7b are exposed using the light sources 8a and 8b and the masks 9a and 9b shown in FIG. 12 (step (d)). Reference numeral 7c denotes a resist exposed to light. Next, the resist not exposed to light is removed with a developer (step (e)), and the exposed portions of the first transparent conductive layer 3a and the second transparent conductive layer 3b are etched (step (f)). Finally, the exposed resist 7c is peeled off to obtain the transparent conductive laminate 10.

  That is, the transparent conductive laminate 10 in FIG. 1 includes a step of forming at least a first transparent conductive layer and a second transparent conductive layer on both sides of a transparent substrate layer, and the first transparent conductive layer and the second transparent conductive layer. Applying a resist to the surface of the transparent conductive layer, a light source and a mask for forming a pattern on the first transparent conductive layer, and a light source and a mask for forming a pattern on the second transparent conductive layer And sequentially exposing the resist applied to the surface of the first transparent conductive layer and the resist applied to the surface of the second transparent conductive layer, respectively, And developing the resist, etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist, and peeling the resist. At least one layer formed between the transparent conductive layer and the second transparent conductive layer is a layer that absorbs light.

  FIG. 13 is a diagram illustrating each step of a method for forming a pattern using a negative resist, but a pattern may be formed using a positive resist.

  Similarly, in the transparent conductive laminate of the present invention shown in FIGS. 2 to 8, the conductive pattern regions 4a and non-patterns formed in the first transparent conductive layer 3a and the second transparent conductive layer 3b by the above-described steps. The conductive pattern region 4b can be formed.

  In the transparent conductive laminate 10 of FIG. 5, the first transparent conductive layer 3a is formed on one side of the first transparent substrate 1a, and the second transparent conductive layer 3b is formed on one side of the second transparent substrate 1b. After the first transparent conductive layer 3a and the second transparent conductive layer 3b are placed outside and the first transparent substrate 1a and the second transparent substrate 1b are bonded together with the adhesive layer 6, the process shown in FIG. c) The following processing is performed.

  That is, the transparent conductive laminate 10 of FIG. 5 includes a step of forming at least a first transparent conductive layer on one side of the first transparent substrate layer, and at least a second transparent conductive layer on one side of the second transparent substrate layer. A step of forming a layer, and a step of bonding the first transparent substrate layer and the second transparent substrate layer together with an adhesive layer with the first transparent conductive layer and the second transparent conductive layer being outside. Applying a resist to the surfaces of the first transparent conductive layer and the second transparent conductive layer, a light source and a mask for forming a pattern on the first transparent conductive layer, and the second A light source and a mask for forming a pattern on the transparent conductive layer are arranged in order from the light source side, and the resist applied to the surface of the first transparent conductive layer and the surface of the second transparent conductive layer are applied. Exposing the resist at the same time; Obtained by the step of developing the resist that has been irradiated, the step of etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist, and the step of peeling the resist, At least one layer formed between the first transparent conductive layer and the second transparent conductive layer is a layer that absorbs light.

  Moreover, it is preferable that the transparent conductive laminated body 10 of this invention performs by the roll to roll system from the process of forming a transparent conductive layer in a transparent substrate layer to the process of peeling the said resist. Thereby, manufacturing time can be reduced significantly.

  The transparent conductive laminate 10 of the present invention preferably has a light transmittance of 60% or more at a wavelength of 400 nm. In this range, the transmitted light hue transmitted through the touch panel is felt neutral, and the boundary between the conductive pattern region and the non-conductive pattern region is difficult to recognize.

  In particular, it is preferable that the light transmittance at a wavelength of 400 nm of the transparent substrate layers 1, 1 a and 1 b, the resin layers 5 a, 5 b or the adhesive layer 6 constituting the transparent conductive laminate 10 is 80% or more.

  In the transparent conductive laminate 10 of the present invention, the difference in total light transmittance between the conductive pattern region and the non-conductive pattern region is 1.5% or less, and the difference in transmitted hue b * is 2. It is preferably 0 or less. In this range, even if different patterns are formed on both surfaces of the transparent conductive laminate, the pattern shape becomes inconspicuous and visibility is improved.

  In addition, the transparent conductive laminate 10 of the present invention preferably has a thermal shrinkage rate of 0.5% or less at 150 ° C. for 30 minutes. In this range, shrinkage due to heat applied in the step of forming the first transparent conductive layer 3a and the second transparent conductive layer 3b and the step of drying the resists 7a and 7b can be suppressed, and the first transparent conductive layer It is possible to prevent displacement of the pattern formed on the layer 3a and the second transparent conductive layer 3b.

  Next, examples and comparative examples will be described.

<Example 1>
Using a polyethylene terephthalate film (made by Toray Industries, Inc., thickness: 100 μm) having an ultraviolet absorbing function as a transparent substrate, a coating solution for forming a resin layer having the following composition was applied to both surfaces of the transparent substrate with a microgravure coater, and 1 at 60 ° C. The resin layer was formed by drying for minutes and curing with ultraviolet rays.

[Composition of resin layer forming coating solution]
Resin: Purple light UV-7605B (manufactured by Nippon Synthetic Chemical) 100 parts by weight Initiator: Irgacure 184 (manufactured by Ciba Japan) 4 parts by weight Solvent: 100 parts by weight of methyl acetate

  Next, 30 nm of ITO was formed as a transparent conductive layer on both surfaces of the resin layer formed on both surfaces of the transparent substrate by a sputtering method. Thereafter, using the photolithography method shown in FIGS. 12 and 13, the patterns shown in FIGS. 9 and 10 are simultaneously formed on both sides under the following exposure conditions, and the conductive pattern region and the non-conductive pattern are formed on the transparent conductive layer. A region was formed.

[Exposure conditions]
Light source: Super high pressure mercury lamp (manufactured by USHIO)
Resist: Chemically amplified resist that is sensitive to wavelengths of 370 nm or less Mask: Diamond pattern shown in FIGS.

<Example 2>
A polyethylene terephthalate film (manufactured by Toray Industries, Inc., thickness: 100 μm) having no ultraviolet absorbing function is used as a transparent substrate, and triazine ultraviolet absorber (2- [4-[(2-hydroxy- (3-tridecyloxypropyl) oxy] -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine) A conductive pattern region and a non-conductive pattern region were formed on the transparent conductive layer under the same conditions and method as in Example 1.

<Comparative example>
A conductive pattern region and a non-conductive pattern region were formed on the transparent conductive layer under the same conditions and method as in Example 1 except that a resist that was sensitive even in a wavelength region including the visible light region was used as the resist.

  The obtained transparent conductive laminate was evaluated by the following evaluation methods.

[Evaluation method]
Light transmittance: The transmittance of the obtained transparent conductive laminate was measured for light transmittance at wavelengths of 400 nm and 370 nm using a spectrophotometer (manufactured by Hitachi High-Tech).
Appearance: The obtained transparent conductive laminate was visually evaluated for color.
Patterning: The pattern shape on both sides of the obtained transparent conductive laminate was visually confirmed, and it was evaluated whether one pattern shape was reflected in the other pattern shape.

The transparent conductive laminate obtained in Examples 1 and 2 has a light transmittance at 400 nm and 370 nm of 61% and 0% in the transparent conductive laminate of Example 1, respectively, and the transparent conductive laminate of Example 2 It was found that the different patterns on both sides of the transparent conductive laminate can be exposed at the same time. Also, the appearance was free from defects such as yellowishness, and the patterns on both sides were not reflected in each other.
On the other hand, the transparent conductive laminate obtained by the comparative example has the light transmittance at 400 nm and 370 nm of 61% and 0% which is the same as in Example 1, and the appearance has no defects such as yellowishness. Regarding the patterns on both sides, it was found that the reflection of each other pattern was prominent, and different patterns on both sides of the transparent conductive laminate could not be exposed at the same time.

  The present invention is used for a transparent touch panel attached as an input device on a display of an electronic device. In particular, it is used for mobile devices capable of multi-touch.

  DESCRIPTION OF SYMBOLS 1 ... Transparent substrate layer, 1a ... 1st transparent substrate layer, 1b ... 2nd transparent substrate layer, 2a, 2b ... Optical adjustment layer, 3a ... 1st transparent conductive layer, 3b ... 2nd transparent conductive layer, 4a ... conductive pattern region, 4b ... non-conductive pattern region, 5a, 5b ... resin layer, 6 ... adhesive layer, 7a, 7b ... resist, 7c ... photosensitive resist, 8a, 8b ... light source, 9a, 9b ... mask 10: Transparent conductive laminate.

Claims (9)

Forming at least a first transparent conductive layer and a second transparent conductive layer on both sides of the transparent substrate layer;
Applying a resist to the surfaces of the first transparent conductive layer and the second transparent conductive layer;
A light source and a mask for forming a pattern on the first transparent conductive layer, and a light source and a mask for forming a pattern on the second transparent conductive layer are sequentially arranged from the light source side, and the first Simultaneously exposing the resist applied to the surface of the transparent conductive layer and the resist applied to the surface of the second transparent conductive layer;
Developing the exposed resist;
Etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist;
Stripping the resist, and
The method for producing a transparent conductive laminate, wherein at least one layer formed between the first transparent conductive layer and the second transparent conductive layer is a layer that absorbs light.   The method for producing a transparent conductive laminate according to claim 1, wherein the transparent substrate layer is a layer that absorbs light, and the transparent substrate layer contains an ultraviolet absorber or a resin having an ultraviolet absorbing function. Further comprising the steps of forming a resin layer on both surfaces of the transparent substrate layer, and forming a first transparent conductive layer and the second transparent conductive layer on the surface of the resin layer,
The method for producing a transparent conductive laminate according to claim 1, wherein the resin layer is a layer that absorbs light, and the resin layer includes an ultraviolet absorber or a resin having an ultraviolet absorbing function. Forming at least a first transparent conductive layer on one side of the first transparent substrate layer;
Forming at least a second transparent conductive layer on one side of the second transparent substrate layer;
A step of bonding the first transparent substrate layer and the second transparent substrate layer together with an adhesive layer, with the first transparent conductive layer and the second transparent conductive layer on the outside;
Applying a resist to the surfaces of the first transparent conductive layer and the second transparent conductive layer;
A light source and a mask for forming a pattern on the first transparent conductive layer, and a light source and a mask for forming a pattern on the second transparent conductive layer are sequentially arranged from the light source side, and the first Simultaneously exposing the resist applied to the surface of the transparent conductive layer and the resist applied to the surface of the second transparent conductive layer;
Developing the exposed resist;
Etching the first transparent conductive layer and the second transparent conductive layer not covered with the resist;
Stripping the resist, and
The method for producing a transparent conductive laminate, wherein at least one layer formed between the first transparent conductive layer and the second transparent conductive layer is a layer that absorbs light.   The method for producing a transparent conductive laminate according to claim 4, wherein the adhesive layer is a layer that absorbs light, and the adhesive layer contains an ultraviolet absorber or a resin having an ultraviolet absorbing function.   The method for producing a transparent conductive laminate according to any one of claims 1 to 5, wherein the resist is a resist that is sensitive to light having a wavelength of 370 nm or less.   The method for producing a transparent conductive laminate according to claim 1, wherein a light absorption region of the light absorbing layer is 370 nm or less.   The transparent conductive laminate according to any one of claims 1 to 7, wherein a process from a step of forming the transparent conductive layer on the transparent substrate layer to a step of peeling the resist is performed by a roll-to-roll method. Body manufacturing method.   The electrostatic capacitance type touch panel using the transparent conductive laminated body manufactured by the manufacturing method as described in any one of Claims 1-8.

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