WO2006090448A1

WO2006090448A1 - Process for producing transparent conductive laminate, and touch panel

Info

Publication number: WO2006090448A1
Application number: PCT/JP2005/002921
Authority: WO
Inventors: Hiroshi Akema; Katsutoshi Sawada; Hironobu Shinohara
Original assignee: Jsr Corporation; Hs Planning Limited
Priority date: 2005-02-23
Filing date: 2005-02-23
Publication date: 2006-08-31
Also published as: JPWO2006090448A1

Abstract

A transparent conductive laminate with a film base that excels in scuff resistance of conductive thin film as well as transparency and excels in dotting performance for application to touch panel; and a touch panel making use of this transparent conductive laminate in at least one of the electrodes thereof. The transparent conductive laminate excelling in not only scuff resistance and dotting performance but also productivity is provided by forming a transparent conductive layer on a specified transparent film under at least ≥ 160°C temperature conditions.

Description

Specification

Method for manufacturing transparent conductive laminate and touch panel

Technical field

The present invention relates to a method for producing a transparent conductive laminate in which a transparent conductive thin film is provided on a film substrate. More specifically, the present invention relates to a method for producing a transparent conductive laminate in which a transparent conductive film is formed on a transparent film under specific conditions.

Background art

[0002] Transparent and conductive thin films in the visible light range include transparent electrodes for liquid crystal displays, electroluminescence displays, plasma displays, and touch panels, as well as antistatic and electromagnetic shielding for transparent devices. It is used for such purposes. Conventionally, such a transparent conductive thin film is known to have an indium oxide thin film formed on glass. Since the base material is glass, it is inferior in flexibility and workability and heavy. It was not preferable because it was easy to break. Therefore, in recent years, various plastic films such as polyethylene terephthalate, polyethersulfone, polycarbonate, norbornene-based resin are used as the base material due to the advantages of lightweight and excellent impact resistance in addition to flexibility and workability. A transparent conductive thin film was used.

Disclosure of the invention

Problems to be solved by the invention

[0003] Conventional transparent conductive thin films produced using such a film base material have poor friction resistance, and there are problems that scratches occur during use, resulting in increased electrical resistance or disconnection. . In particular, in a conductive thin film for a touch panel, a pair of thin films opposed to each other via a spacer come into strong contact with each other at a pressing point from the one side of the substrate. Although it is desired to have good durability characteristics, that is, hitting characteristics, the conventional transparent conductive thin film is inferior to such characteristics and has a problem that the life of the touch panel is shortened.

[0004] In order to solve this problem, Japanese Patent Publication No. 2667680 discloses that a conductive thin film is formed in advance on one surface of a transparent plastic substrate having a specific thickness by sputtering or the like. Later, a transparent conductive laminate has been proposed in which a transparent substrate is bonded to the other surface via a transparent adhesive having specific characteristics. In this method, the pressure-sensitive adhesive acts as a cushion, and although the abrasion resistance of the transparent conductive thin film can be greatly improved, the adhesion between the film and the transparent conductive film is essentially insufficient. The lack of durability has not been solved, and there have been problems such as a decrease in transparency and an increase in work processes due to the bonding with the film.

[0005] The present invention has been made in view of the above-mentioned problems, and improves the scratch resistance and the spot characteristics of the transparent conductive thin film formed on the film substrate, and has excellent productivity. The object is to provide a method for producing a conductive laminate.

Means for solving the problem

[0006] The method for producing a transparent conductive laminate of the present invention is characterized in that a transparent conductive film is formed on a transparent film while maintaining the temperature of the film at 160 ° C or higher. According to this method, it is possible to produce a transparent conductive laminate excellent in scratch resistance and hit point characteristics with high productivity.

The invention's effect

[0007] According to the present invention, by forming a transparent conductive film on a transparent film under a temperature condition of at least 160 ° C, a transparent conductive laminate having excellent scratch resistance and spot characteristics is produced. Can be manufactured well.

BEST MODE FOR CARRYING OUT THE INVENTION

[0008] The film base material used in the present invention is transparent and does not change in quality such as deformation or discoloration of the base material in the process of forming a transparent conductive film at a temperature of 160 ° C or higher. Various plastic films can be used. Specific examples include polyimide, polyether sulfone, polyether ether ketone, polycarbonate, polyamide, polyacryl, acetyl cellulose, polyarylate, polysulfone, and norbornene resin.

[0009] When used for a transparent electrode of a display such as a liquid crystal display, from various viewpoints such as optical properties such as transparency and non-rotatory properties, low water absorption, heat resistance, physical properties such as mechanical strength, and price. Since film base materials are selected, each film base material has a long From the standpoint of overall strength, polycarbonate, polyethersulfone and norbornene resins are preferred. In recent years, quality of image quality and dimensional stability at high temperature and high humidity have been emphasized. From this viewpoint, transparency, light dispersibility (refractive index is the wavelength dependence of birefringence), and non-optical rotation. A norbornene-based resin that is far superior to other polymers in optical properties such as heat resistance and low water absorption is particularly preferable.

[0010] The norbornene-based resin includes a polymer obtained by subjecting a monomer having a norbornene structure and other polymerizable monomer added as necessary to ring-opening polymerization or addition polymerization. In particular, a cyclic olefin-added copolymer containing at least one repeating unit derived from the cyclic olefin represented by the following formula (1) is preferable.

[0011] [Chemical 1]

[In the formula (1), A ^{1 to} A ⁴ each independently represents a hydrogen atom, a halogen atom, an aralkyl group having 1 to 20 carbon atoms, an alkenyl group, a cycloalkyl group, an aryleno group, or a halogenated hydrocarbon group. , An ester group, an alkoxy group, a trialkylsilyl group, a hydrolyzable silyl group, and a substituent including an oxetanyl group. These substituents are further alkylene groups having 1 to 10 carbon atoms or oxygen They may be linked via a linking group having 1 to 10 carbon atoms including atoms. A ¹ and A ² or A ¹ and A ⁴ may be bonded to each other to form an alkylene group, an arylene group, an acid anhydride, or a rataton. m is 0 or 1. ]

When the cyclic olefin-based addition polymer optionally contains a repeating unit of a substituted cyclic olefin having an alkyl group, it is possible to improve the molding force properties such as controlling the glass transition temperature of the obtained cyclic olefin-based polymer. Flexibility can be imparted to the film base. [0013] Further, when the cyclic olefin-based addition polymer includes a repeating unit having a hydrolyzable silyl group or a substituent containing an oxetanyl group, a compound that generates an acid by heating or light irradiation (hereinafter, referred to as the following). A cross-linked structure is formed by the action of “thermal acid generator” and “photo acid generator”, respectively, and the chemical resistance or mechanical strength of the obtained film substrate can be improved. Here, the hydrolyzable silyl group forms a siloxane bond through a hydrolysis Z-condensation reaction with an acid catalyst and water or water vapor supplied as appropriate, thereby enabling cross-linking between the silyl groups. These are represented by the following formula (2) or the following formula (3).

[0014] [Chemical 2]

-S i R ^a R ² R ³ '· Formula (2)

[In the formula (2), at least one of R ¹ , R ² , R ³ represents a substituent selected from an alkoxy group, an aryloxy group, and a halogen atom; It is an alkyl group. ] [0016] [Chemical 3] C

R ⁴ · · · ■ Formula (3)

[In the formula (3), R ⁴ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Y represents a hydrocarbon of an aliphatic diol, alicyclic diol or aromatic diol having 2 to 20 carbon atoms. Indicates a residue. ]

The ratio of the strong crosslinkable repeating units in the whole repeating units is usually 30 mol% or less, preferably 20 monole%, more preferably 15 mol% or less. If it exceeds 30 mol%, the water absorption of the film substrate may increase, or the shrinkage during crosslinking may be large, which may be inappropriate for the intended use.

[0018] As the thermal acid generator, a compound capable of generating an acid at 50 ° C or higher is preferably used, and as the photoacid generator, g-line, h-line, i-line, ultraviolet ray, far-ultraviolet ray, A compound that generates Bronsted acid or Lewis acid by irradiation with X-ray, electron beam or the like is used. These can be selected from known substances as appropriate. May be. The thermal acid generator and the photoacid generator can be used in the range of 0.001 to 10 parts by weight, preferably 0.01 to 5.0 parts by weight per 100 parts by weight of the cyclic olefin-based addition polymer. . If the amount is less than 001 parts by weight, the effect of crosslinking cannot be sufficiently obtained. If the amount exceeds 10 parts by weight, the mechanical strength, electrical properties and transparency of the film substrate may be impaired.

[0019] As monomers used for obtaining these cyclic olefin-based addition polymers, those having an unsaturated bond not involved in polymerization, such as tricyclo [5. 2. 1. 0 ² ' ⁶ ] deca-3, 8 -When Jen (dicyclopentagen) ethylidene norbornene is used, the film base material is susceptible to deterioration at high temperatures. Such a problem can be avoided by hydrogenating 90 mol% or more, preferably 95 mol% or more, more preferably 99 mol% or more of the unsaturated bond after addition polymerization of these cyclic olefins. The hydrogenation reaction can be carried out using a known heterogeneous catalyst or homogeneous catalyst as appropriate, usually at a hydrogen pressure in the range of 1.015 MPa and a temperature in the range of 50-250 ° C.

[0020] The glass transition temperature of the resin constituting these film substrates is at least 180 ° C or higher, preferably 200 ° C or higher, more preferably 230 ° C or higher, and particularly preferably 250 to 400 ° C. The When the glass transition temperature is 180 ° C. or lower, the film substrate may become unpractical due to deformation or shrinkage during film formation of the transparent conductive film.

Furthermore, the film substrate of the present invention preferably has a retardation of 15 Å or less and a total light transmittance of 90% or more at a film thickness of 100 μm. If the retardation is more than 15 awakens, it will be difficult to use the inner type touch panel with circular polarizing film on the upper substrate. Also, if the total light transmittance is less than 90%, there will be inconveniences such as darkening the panel screen.

[0021] In addition, in the film, additives that are usually mixed in the film, such as antioxidants, mold release agents, ultraviolet absorbers, lubricants, and coloring agents, as necessary, and further for crosslinking reaction. Auxiliaries and the like can be added for various purposes. The method for producing the film substrate is not particularly limited, and can use known melt extrusion methods, solution casting methods, coating methods, and the like. From the viewpoint of film surface smoothness, the solution casting method Film base manufactured by Nya coating method is preferred. If necessary, film production In the process, the crosslinking reaction can be performed by heat, light, water vapor or the like.

In the present invention, the thickness of the film substrate is preferably about 2 to 400 μm. If it is thinner than 2 μm, the mechanical strength of the base material itself is insufficient, and it becomes difficult to perform continuous operations such as applying a pressure-sensitive adhesive layer in the form of a roll or performing a hard coating process described later. From this point of view, a thickness of 10 zm or more is preferred, and a thickness of 20 zm or more is particularly preferred. If it is 400 zm or more, it will be scratched if it is rolled, and if continuous work is difficult, it will not be able to be used because force, glue, or wrinkles will remain. From such a viewpoint, the preferable thickness is 300 μm or less, and particularly preferably 250 μm or less.

[0023] This film base material is preliminarily subjected to etching treatment or undercoating treatment such as sputtering, corona discharge, flame, ultraviolet irradiation, electron beam irradiation, chemical conversion, oxidation, and the like, and a conductive thin film provided thereon It is also possible to enhance the adhesion of various coating agents and thin films formed on the surface of the film in order to function as needed. In addition, before providing the conductive thin film, etc., it may be removed and cleaned by washing with a solvent, water, acid, alkali or the like, or ultrasonic cleaning, if necessary.

[0024] The film bases used in the present invention can be used by bonding the film bases to each other or different film bases with an adhesive or an adhesive. This bonding can be carried out by providing a pressure-sensitive adhesive layer or an adhesive layer on one side of the transparent film substrate and bonding the other film substrate to this. This laminating can be carried out by appropriately selecting a known method, but it is advantageous in terms of productivity to carry out the film continuously in a roll shape. The pressure-sensitive adhesive layer and the adhesive layer are not particularly limited as long as they have transparency.

[0025] In order to form the transparent conductive laminate of the present invention, a transparent conductive thin film is formed on one outer surface of the film substrate. As a method for forming a conductive thin film, conventional techniques such as vacuum deposition, sputtering, and ion plating can be used. From the viewpoint, thin film formation by sputtering is preferable. The thin film materials used are not particularly limited, for example, metal oxides such as indium oxide containing tin oxide and tin oxide containing antimony, as well as gold, silver, platinum, palladium, copper, anoleminium, nickel Chrome, titanium, cobalt, tin Or these alloys are preferably used. The thickness of this conductive thin film needs to be 30 A or more, and if it is thinner than this, it is difficult to form a continuous film having good conductivity with a surface resistance of 1000 Ω / mouth or less. On the other hand, if the thickness is too large, the transparency is lowered. Therefore, a suitable thickness is about 50 2000 A.

In the present invention, it is important to control the temperature at which the transparent conductive film is formed. Conventional film sputtering has been performed at temperatures below 100 ° C. The sputtering temperature greatly affects the adhesion between the film substrate and the transparent conductive film. When a film is formed at a temperature of 160 ° C or higher, a transparent conductive laminate having excellent durability can be obtained. In order to further reduce the resistance value, film formation at 180 ° C or higher is more preferable, and film formation at 200 ° C or higher is particularly preferable.

[0027] When a transparent dielectric thin film is formed on the conductive thin film thus formed, the transparency, scratch resistance, and spot characteristics are further improved, and a more preferable transparent conductive laminate is obtained. It is This dielectric thin film should have a refractive index smaller than that of the conductive thin film, usually 1.3-2.0, preferably 1 · 3-1.6. For example, CaF, MgF, NaAlF, Al

Of these, Ox, SiOx (x = l-2), and ThF are preferred. SiOx is most preferred. These materials can be used in combination of two or more according to the purpose. The dielectric film thickness should be 100A or more, preferably 100 to 3000A, and preferably 200 to 1500A. If the film is thin, it is difficult to obtain a continuous film, and if the transparency is small, the effect of improving the scratch resistance is small. If the film is thick, the conductivity is deteriorated and the cracks are likely to occur. The dielectric can be formed by a known method such as a vacuum deposition method, a sputtering method, an ion plating method, or a coating method.

[0028] Next, various functions may be imparted to the transparent conductive laminate depending on the purpose. This will be described below. The film substrate is prone to scratches during the formation of the transparent conductive thin film, the subsequent processing or assembly of the device, and in the laminate, the surface opposite to the surface on which the conductive thin film is formed is bare. In order to avoid this problem, it is preferable to use a film substrate that has been subjected to a hard coat treatment in order to avoid this problem. . [0029] The hard coat treatment can be performed on both sides or one side of the film before or after the transparent conductive film is formed. It is particularly preferable to perform the hard coat treatment on the outer surface on the opposite side of the conductive thin film in the laminate. The hard coat treatment layer is preferably a cured film made of a curable resin such as melanin resin, urethane resin, alkyd resin, acrylic resin, or silicon resin. Among the hard coat treatment layers, an acrylic resin is preferably used because it can enhance the adhesion of the conductive thin film and has an effect as a base agent before forming the conductive film.

[0030] In forming such a cured film, a composition obtained by adding various additives such as an antistatic agent and a polymerization initiator to the above-described curable resin as necessary is usually diluted with a solvent. The solid content is 20 to 80% by weight, and this is applied to one side of a transparent film substrate by a general solution coating method such as gravure coater, reverse coater, spray coater, slot orifice coater or screen printing. By such means as described above, the coating can be applied so that the thickness after drying and curing is about 115 μm, and after curing by heating, it can be cured by ultraviolet irradiation, electron beam irradiation or heating. Prior to the formation of this hard coat treatment layer, the adhesion between the transparent film and the hard coat treatment layer is achieved by subjecting the adherend surface to easy adhesion such as corona discharge, ultraviolet irradiation, plasma treatment, sputter etching treatment, and primer treatment. Can be increased.

[0031] In addition, since the surface opposite to the surface on which the transparent conductive film is formed in the transparent conductive laminate is bare, when it feels dazzling or the surface is scratched, There was a problem of poor visibility in products using transparent conductive thin films. In order to solve this problem, an antiglare treatment agent coated on the outer surface of the film is preferably used.

The anti-glare treatment agent is preferably a cured film obtained by dispersing and binding silica particles to the hard coat agent described above. The silica particles used here are amorphous and porous, and a typical example is silica gel. The average particle size is usually 30 xm or less, preferably about 2 to 15 zm, and the blending ratio is such that the silica particles are 0.1 to 1 10 parts by weight with respect to 100 parts by weight of the resin. Is preferred. When the amount of silica particles is small, the antiglare effect is inferior. When the amount is large, the light transmittance and the film strength are lowered. The antiglare treatment agent can be applied to the film and hardened in exactly the same manner as the hard coat treatment described above. Anti-glare treatment agent It also serves as an anti-glare effect and also provides a scratch prevention effect.

Next, a transparent conductive laminate provided with an antireflection layer will be described. A transparent conductive thin film is used in a display device, and when light is reflected on the surface, the image becomes unclear, and in some cases, the image is difficult to see. A transparent conductive laminate having a high light transmittance, excellent scratch resistance on the surface of the base material, and also having an antireflection function capable of preventing light reflection on the surface of the base material is more preferable in practical use. It is.

[0033] After the formation of the conductive thin film, the antireflection layer is formed on the outer surface where the conductive thin film is not formed. This antireflection layer includes a single layer structure having a refractive index different from that of the film substrate or a multilayer structure of two or more layers. In the single layer structure, a material having a refractive index smaller than that of the film substrate is selected. In order to improve the antireflection effect, in the case of a multilayer structure, a material layer having a larger refractive index than that of the film substrate is provided, and a material layer having a smaller refractive index is provided thereon. P is a force that uses a material structure with a different refractive index between the P-contact layers. More preferably, the outermost layer has a refractive index smaller than the refractive index of the lower layer adjacent to the multilayer structure of three or more layers. It is advisable to use a suitable material structure. As a material for constituting such an antireflection layer, for example, CaF

, MgF, NaAlF, Al〇, SiOx (x = l-2), ThF, ZrO, Sb〇, NdO, SnO,

Derivatives such as TiO and InO are mentioned. The refractive index is appropriately selected so as to satisfy the above relationship. This antireflection layer can be formed by a thin film formation technique similar to that of the conductive layer. The thickness is selected so that the total thickness of the antireflection layer is generally about 500 to 5000 A. This layer also increases the hardness of the surface, thus improving the scratch resistance.

[0034] Further, since this transparent conductive laminate is used in a display device, fingerprints and dirt are generated on the surface during processing and use, and there is a problem in visibility as a whole thin film product such as feeling glare. There was a case. In order to solve this problem, a transparent conductive laminate having a water-repellent and antifouling treatment layer on the outer surface of the laminate is preferred depending on the application. The water repellent and antifouling treatment layer can be formed on the outer surface of the film in the same manner as the hard coat formation. Examples of the material for forming such a water-repellent and antifouling treatment layer include dimethylpolysiloxane containing a hydroxyl group or a bur group and methyl. A silicon-containing compound comprising a combination with a hydrodiene polysiloxane, a fluorine resin such as polytetrafluoroethylene or polychloroethylene, molybdenum sulfide or the like is used alone or as a compound. In order to improve the adhesion and hardness of the treatment layer, it may be dispersed and bonded to the curable resin such as the hard coat agent described above and provided as a hardened film layer on the substrate surface. In addition, the silica particles can be dispersed for the purpose of improving anti-glare effect and scratch resistance. The formation of the water-repellent and antifouling layer is not particularly limited, and a coating method, a spray method, a vacuum deposition method, a sputtering method, an ion plating method, a baking method, or the like can be used depending on the material used. The thickness of the treatment layer is not particularly limited, but is usually about 100 A 50 xm. If it is thin, it is difficult to obtain a continuous film, and if the water-repellent effect is poor, cracks are likely to occur.

[0035] The above functionalization treatment can be carried out in combination of two or more, and it is particularly efficient when a hard coat agent, an antiglare treatment and a water repellent or antifouling treatment agent are used in combination. .

[Example]

Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1

[0036] <Synthesis of norbornene resin, production of film substrate>

Bicyclo [2. 2. 1] hepta-2-ene as a monomer is 700 millimonole, endo-tricyclo [5, 2, 1, 0 ² ' ⁶ ] deca _8-en (endo / exo = 96/4 ) 570 millimonole, 5_triethoxysilinorebicyclo [2. 2. 1] hepta-2-ene 30 mmol, 1-hexene 5 mmol, solvent 400 g cyclohexane, methylene chloride 100 g 2 L A stainless steel reactor was charged under nitrogen.

[0037] A solution of nickel octanoate in hexane and hexafluoroantimonic acid at 10 ° C, molar ratio 1

: Reacted in 1, precipitate of bis (hexafluoroantimonate) nickel and [Ni (SbF)] byproduct was removed by filtration and diluted with toluene. The resulting hexaoctammonium-modified antimonic acid modification of nickel octanoate is 0.40 mmol, boron trifluoride etherate 1 · 2 mmol, methylalumoxane 8.0 · millimonole, 1,5-cycloocta Gen 0.4 millimonore, methinorelie oxysilane 8.0 millimonore, methinoreoxy xylan, 1, 5- Polymerization was started by charging cyclooctagen, methylalumoxane, boron trifluoride etherate, and nickel oxaloantimonic acid modified product of nickel octanoate in this order. Polymerization was carried out at 30 ° C. for 3 hours, and methanol was added to terminate the polymerization. Conversion of monomer to copolymer is 92. /. Met.

[0038] The copolymer solution was diluted by adding 480 g of cyclohexane, 660 ml of water and 48 mmol of lactic acid were added thereto, and the mixture was sufficiently stirred and mixed, and then the copolymer solution and the aqueous phase were allowed to stand and be separated. The aqueous phase containing the reaction product of the catalyst component was removed, and the copolymer solution was put into 4 L of isopropyl alcohol to solidify the copolymer, thereby removing unreacted monomers and catalyst residues. The coagulated copolymer was dried to obtain 75 g of cyclic olefin-based addition polymer A (hereinafter also referred to as “copolymer A”).

[0039] 5_ triethoxysilypropoxy ruby cycloalkyl in the copolymer A [2. 2.1] of the repeating unit derived from Heputa 2 E emissions is 2.1 mole ^_0/0, endo- tricyclo [5, 2 , 1, 0 ² ' ⁶ ] Deca-8-en, the proportion of repeating units was 35 mol%. The number average molecular weight of the copolymer converted to polystyrene was 89,000, the weight average molecular weight was 187,000, and Mw / Mn was 2.1.

[0040] Next, the copolymer AlOg was dissolved in 35.5 g of cyclohexane, and pentaerythrityl tetrakis [3— (3,5-di-tert-butyl-4-hydroxyphenyl) propione as an antioxidant. 1.0 parts with respect to 100 parts of the copolymer and 0.5 parts of tributyl phosphite as a crosslinking catalyst with respect to 100 parts of the copolymer. The copolymer solution was cast, and the resulting film was dried at 150 ° C. for 2 hours and further dried at 200 ° C. for 1 hour under vacuum. Furthermore, this film was heat-treated under steam at 150 ° C for 4 hours. Then, it was dried at 200 ° C for 1 hour under vacuum to produce a crosslinked film Α having a thickness of 100 µm.

[0041] The film A obtained had the following characteristics: total light transmittance: 91%, glass transition temperature: 375 ° C, retardation: 5 mm.

An indium-tin oxide (ITO) film was formed on a sheet having a length of 200 mm, a width of 200 mm, and a thickness of 100 μm obtained by the same operation as described above using a sputter machine under the following conditions.

[0042] Substrate temperature: 200 ° C Target: In O / SnO = 90/10 (weight ratio) alloy

2 3 2

Atmosphere: Under argon gas flow

Sputter speed: 80 A / min

Sputtering pressure: 10- ³ torr

Table 1 shows the measured average resistance, transmittance, scratch resistance, and spot characteristics of this conductive thin film.

Example 2

[0043] Using the same film A as in Example 1 as the film base, ITO film formation was carried out in the same manner as in Example 1 except that the substrate temperature was changed to 250 ° C.

Example 3

[0044] A Teijin Pure Ace (R) WR (aromatic polycarbonate) film having a thickness of 100 µm was used as a film substrate. The properties of this film were a total light transmittance of 90%, a glass transition temperature of 210 ° C., and a retardation of 20 nm. Using this film, IT ○ film formation was carried out in the same manner as in Example 1 except that the substrate temperature was changed to 180 ° C.

Example 4

[0045] Into a 2L stainless steel reactor sufficiently purged with nitrogen, 750g of dehydrated toluene and 200g of cyclohexane were charged, and 150g, 75 weight of 5-butylbicyclo [2.2.1] hepta_2_en was added. ^_0/0, and bicyclo [2.2.1] was added 170g of toluene solution of hept _2_ E down. Ethylene was introduced until the partial pressure at 20 ° C reached 0.015 MPa, and then the reactor valve was closed and the temperature was raised to 75 ° C. Subsequently, 0.005 mol / l of palladium acetate in toluene solution was added in 1. lml, 0.002 mol / l of tricyclohexylphosphine in toluene was added in 2.75 ml, 0.001 mol / l of triphenylcarbtetrakis (penta Polymerization of 5.5 ml of fluorotoluene) borate in toluene was started. When 60 minutes and 90 minutes have elapsed after the start of polymerization, 15 g of each of the above tons of bicyclo [2.2.1] hepta-2-ene was added. The polymerization was continued for a total of 4 hours. Conversion of all monomers to polymer was 99%. The obtained copolymer solution is solidified by pouring into about 10 L of isopropyl alcohol, dried under vacuum at 80 ° C. for 17 hours, and then cyclic olefin-based copolymer B (hereinafter also referred to as “copolymer B”). ) Was obtained. In copolymer B, the proportion of repeating units derived from 5-butylbicyclo [2.2.1] hepta-2-ene is 39 mol%, the number average molecular weight is 42,000, and the weight average molecular weight is 175,000. Met.

[0046] 100 parts by weight of copolymer B was dissolved in a mixed solution consisting of 280 parts by weight of toluene and 70 parts by weight of cyclohexane, and pentaerythrityl tetrakis [3- (3,5_di-t-butyl) as an antioxidant. _4-hydroxyphenyl) propionate] and tris (2,4-di-t_butylphenyl) phosphite were each added by 0.6 parts by weight. The obtained copolymer solution was filtered through a membrane filter having a pore size of 10 zm, and then cast at 25 ° C. The resulting film was dried at 160 ° C for 2 hours to prepare a film B having a thickness of 100 zm. The resulting film B has a total light transmittance of 93%, a glass transition temperature of 345 ° C, and a retardation of 5 nm.

[0047] Using the obtained film B, ITO film formation was carried out in the same manner as in Example 2. Table 1 shows the measured average resistance, transmittance, scratch resistance, and spot characteristics of this conductive thin film.

Comparative Example 1

[0048] A JSR Arton (R) (norbornene-based) film having a thickness of 100 µm was used as a film substrate. The characteristics of this film were total light transmittance: 90%, glass transition temperature: 170 ° C., and retardation: 3 nm. IT ○ film formation was carried out in the same manner as in Example 1 except that this film was used and the substrate temperature was changed to 130 ° C.

Comparative Example 2

[0049] Using a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 25 μm as the film substrate, the substrate temperature was changed to 50 ° C, and the same method as in Example 1 was used. Membrane was performed. Next, on the other side of the PET film, an acrylic transparent adhesive layer (modulated with butyl acrylate) with an elastic modulus adjusted to 1.2 x 10 6 dyn / cm ² A copolymer of acrylic acid and vinyl acetate with a 100: 2: 5 copolymer (100 parts by weight and 1 part by weight of an isocyanate cross-linking agent) is formed to a thickness of about 20 μΐη. Laminated PET film with a length of 100 / m. Table 1 shows the measured average resistance, transmittance, scratch resistance, and spot characteristics of this conductive thin film.

[0050] The characteristics of the film substrate were as follows.

Total light transmittance '' Conforms to ASTM—DIOOS and measured with a film with a thickness of 100 μm. Glass transition temperature · Dynamic viscoelasticity tan δ (storage modulus E 'and loss modulus Ε) Ratio) The glass transition temperature of the film substrate was measured at the peak temperature.The dynamic viscoelasticity was measured using Leovibron DDV-01FP (Orientec), the measurement frequency was 10Ηζ, and the heating rate was 4

It was determined at the peak temperature of the temperature dispersion of tan δ obtained using ° C / min, the excitation mode having a single waveform, and the excitation amplitude force ¾.5 μm.

[0051] Retardation '· By measuring the phase difference Δ of the elliptical deflection by the elliptical deflection analysis method using the rotation analyzer complete automatic ellipsometer (manufactured by Mizojiri Optical Co., Ltd.), the following formula (1 ) The return value Re was calculated. In addition, the incident light angle of the laser beam was set to 0 °, and the retardation was evaluated.

Δ = -k (n -n) d = _k Re (1)

0 x y 0

Where k is the wave number (= 2π / e), η, η, η are the coordinates orthogonal to the three-dimensional refractive index of the film

0 z

Each index of refraction when taken in the system X, y, z, d is the film path length.

[0052] The method for measuring the characteristics of the produced transparent conductive laminate is as follows.

• Average resistance value ·········································································································· • Transmittance ··· A spectral transmittance meter was used to determine the light transmittance at a wavelength of 550 nm.

'Scratch resistance ··· Using a Haydon surface measuring machine, with a gauze with a load of 90 g / cm ² , rubbing the surface of the thin film at a scratch rate of 30 cm / min and a number of scratches of 100 times, the resistance value (Rs ) Was measured, and the rate of change relative to the initial value (Ro) was determined.

• Dot characteristics ······································································································ Using 7R), the resistance value is measured after performing center hitting 1 million times with a load of 90g. (Rd) was measured, and the rate of change with respect to the initial resistance value (Ro) was determined.

[0053] [Table 1]

One table

As can be seen from the above results, in the present invention, the transparent conductive laminate is formed by sputtering the conductive thin film while maintaining the film substrate at a temperature of 160 ° C. or higher. Since the strength of the film is increased when the conductive thin film is formed by wrapping, a transparent conductive laminate having excellent scratch resistance and spot characteristics can be obtained.

In particular, when a conductive thin film is formed by sputtering at 230 ° C or higher, preferably 250 ° C or higher, using a norbornene-based resin as a film substrate, a transparent conductive laminate having excellent scratch resistance can be obtained.

Claims

The scope of the claims

[1] A method for producing a transparent conductive laminate, comprising forming a transparent conductive film on a transparent film while maintaining the temperature of the film at 160 ° C or higher.

[2] The production method according to claim 1, wherein the transparent conductive film is formed while maintaining the temperature of the film at 200 ° C or higher.

[3] Transparent film force The production method according to claim 1, comprising a substantially amorphous polymer having a glass transition temperature of 180 ° C or higher.

[4] Transparent film force The production method according to any one of claims 1 and 2, comprising a substantially amorphous polymer having a glass transition temperature of 200 ° C or higher.

[5] Transparent film strength The production method according to any one of claims 1 to 4, wherein the retardation at a film thickness of 100 μm is 15 nm or less and the total light transmittance is 90% or more.

[6] The production method according to any one of claims 1 to 5, wherein the transparent film comprises a composition containing a polymer containing at least one repeating unit represented by the following formula (1):

[Chemical 4]

[In the formula (1), A ^{1 to} A ⁴ are independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group, a cycloalkyl group, an aryleno group, a halogenated hydrocarbon group, an ester. Group, alkoxy group, trialkylsilyl group, hydrolyzable silyl group, substituent selected from oxetanyl group, and these substituents further include an alkylene group having 1 to 10 carbon atoms or an oxygen atom It may be linked via a linking group with 1 to 10 carbon atoms. A ¹ and A ² or A ¹ and A ⁴ may be bonded to each other to form an alkylene group, an arylene group, an acid anhydride, or a rataton. m is 0 or 1. ]. A transparent conductive laminate obtained by the method according to claim 11.

A touch panel having the transparent conductive laminate according to claim 7 as at least one electrode.