JPH0792674A - Spacer material for touch panel and touch panel using that - Google Patents

Abstract

PURPOSE:To obtain such a material that a pattern can be written by contact exposure and developed with an alkali aq. soln. by incorporating a (meth) acrylate compd. obtd. by the reaction of a specified epoxy(meth)acrylate and polybasic acid or its acid anhydride. CONSTITUTION:This spacer material for a touch panel consists of a photosensitive resin material containing a (meth)acrylate compd. The (meth)acrylate compd. is obtd. by the reaction of an epoxy(meth)acrylate expressed by the formula and a polybasic acid or its acid anhydride. I the formula, R1 and R2 are hydrogen atoms, alkyl groups of 1-5 carbon number, or halogen atoms, R. is hydrogen atom or methyl group, X is -CO-, -SO2-, -C(CF3)2, -Si(CH3)2-, -CH2-, -C(CH3)2-, or -O- pr R3 is not present, and P is an integer 0 to 10. The bisphenol component expressed by the formula which constitutes the (meth) acrylate compd. is derived from bis(4-hydroxyphenyl) ketone, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer material made of a photosensitive resin and a touch panel using a cured product thereof. More specifically, a spacer as an insulating separator for a touch panel is formed by utilizing the photosensitivity of this material, or when a pattern is formed on a substrate by a resist operation, a coating film is formed after pre-curing, which is a solvent removal process. Since it is tack-free, it provides a material capable of accurate pattern writing by contact exposure and further developing with an alkaline aqueous solution. The obtained cured product becomes a touch panel spacer having excellent hardness, transparency, adhesion, flatness, heat resistance, and chemical resistance.

[0002]

2. Description of the Related Art With the widespread use of computers, there is an increasing demand for a touch panel capable of inputting by simply touching the display surface of a display with a finger or a specific pen. This touch panel is used as an ATM (Automatic Teller Machine) device at a bank counter, a plant control system, a search system, and an electronic game as a selection input method of various information.

Touch panels have been developed which utilize various different principles such as optical type, capacitive type, acoustic type, pressure detecting type and membrane type [Reference: Elizabeth Panthaya, Nikkei Electronics, 1984, 7 (2), p213
(1984) and Yuji Mitani, PIEL, No.39 (1985)]
However, the present invention is to provide a spacer material suitable for a method in which two transparent conductive films or one of the two transparent conductive films is made to face each other with a transparent electrode substrate such as glass with a spacer interposed therebetween.

Up to now, as a material used for the spacer, a transparent ink such as an acrylic resin type, an epoxy resin type, a polyester resin type, a urethane resin type, or a silicone resin type has been used, which is a heat drying type or a UV curing type. Etc. are exemplified as usable [Japanese Patent Laid-Open No. 5-18
9,150, JP-A-5-242,759,
Saburo Tabata, CMC Publishing, "Manufacturing and Application of Transparent Conductive Film," Chapter 12 (1986)].

A screen printing method has been widely used as a method of forming a spacer pattern using these spacer materials. When such a screen printing method is used,
In many cases, a phenomenon such as bleeding, bleeding, or sagging at the time of printing occurs, which makes it difficult to deal with the recent high precision and high density of the touch panel due to pen input or the like.

To solve these problems, there are dry film type photoresists and liquid developable resist inks made of the same spacer material. In the case of dry film type photoresists, thermocompression bonding is used. In this case, there are problems that bubbles are likely to be generated, heat resistance and adhesion are uneasy, and that the price is high.

On the other hand, in the case of forming a spacer by photolithography, a resist which can be peeled off is applied after forming a pattern on the above spacer material, then a desired pattern is formed on the resist, and the spacer is formed by a suitable developing solution. A method of etching the material and removing the resist can also be adopted. However, this method has a problem in that the number of steps is increased due to the addition of resist coating and peeling steps, resulting in poor economic efficiency.

Further, it has been proposed to form a spacer pattern by making the spacer material itself photosensitive (Japanese Patent Laid-Open No. 5-189,150). However, the liquid resist used at this time has a tack after pre-curing, which causes contamination of the mask, and there is a problem that the contact exposure operation, which is advantageous in increasing resolution and tapering, cannot be applied. Further, since the ones currently on the market use an organic solvent as a developing solution, there is a problem of air pollution, and the solvent is expensive.

For example, Japanese Patent Application Laid-Open No. 61-243,869 discloses a photosensitive resin composition which can be developed with a weak alkaline aqueous solution containing a phenol novolac resin as a main component, but has a high crosslinking density. In addition, there was a problem that the adhesiveness to the substrate after curing was lowered and the spacers fell off in this application. Further, JP-A-5-70,528 and JP-A-4-355450 disclose a heat-resistant alkali-developable liquid resist, but do not describe anything about application to a touch panel. .

[0010]

Therefore, in view of these conventional problems, the present inventors have synthesized photopolymerizable oligomers having a carboxyl group based on various epoxy acrylates, and have earnestly studied the function thereof. As a result, the present invention has been reached and the present invention has been completed. Therefore, an object of the present invention is to form a touch panel spacer material having no such defects as described above after patterning on a substrate by a photolithography operation of the material, after the precure which is a solvent removal step, the coating film is tacky. The purpose is to provide a material that can be written in a precise pattern by contact exposure because it is free, and further that enables an alkaline aqueous solution phenomenon. The spacer as an insulating separator obtained by curing provides excellent hardness, transparency, adhesion, flatness, heat resistance, and chemical resistance.

[0011]

That is, the present invention provides the following general formula (1):

[0012]

[Chemical 5]

[However, in the formula (1), R ₁ and R ₂
Is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a halogen atom, R ₃ is a hydrogen atom or a methyl group, and X is —CO—, —SO ₂ —, —C (CF ₃ ) ₂ ,-
_{Si (CH 3) 2 -,} - CH 2 -, - C (CH 3) 2 -
, -O-,

[0014]

[Chemical 6] Or absent, p is an integer of 0 to 10] and a photosensitizer containing a (meth) acrylate compound obtained by reacting an epoxy (meth) acrylate represented by the formula with a polybasic acid or an acid anhydride thereof. It is a spacer material for a touch panel made of a conductive resin material. Furthermore, the present invention relates to a touch panel having a cured product of the material as a spacer.

The present invention will be described in detail below. In the present invention, specific examples of the bisphenol component in the unit structure represented by the general formula (1) that constitutes the (meth) acrylate compound include bis (4-hydroxyphenyl) ketone containing -CO- as X, Bis (4-hydroxy-3,5-dimethylphenyl) ketone, bis (4-hydroxy-3,5-dichlorophenyl) ketone, etc., and bis (4-hydroxyphenyl) sulfone containing --SO ₂ --as X , bis (4-hydroxy-3,5-dimethylphenyl) sulfone, bis (4-hydroxy-3,5-dichlorophenyl) sulfone, further, -C as X (CF _{3) 2} - bis (4 as comprising -Hydroxyphenyl) hexafluoropropane, bis (4-hydroxy-3,5-dimethylphenyl) hexaph Oropuropan, bis (4-hydroxy-3,5-dichlorophenyl) hexafluoropropane and the like, also, -Si as X (CH _{3) 2} - bis as containing (4-hydroxyphenyl) dimethylsilane,
Bis (4-hydroxy-3,5-dimethylphenyl) dimethylsilane, bis (4-hydroxy-3,5-dichlorophenyl) dimethylsilane and the like, and X with —CH ₂ —.
Bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dichlorophenyl) methane, bis (4-hydroxy-3,5-dibromophenyl) methane, phenol novolac, cresol novolac, etc. , -C as X (CH _{3) 2} - 2,2- bis (4-hydroxyphenyl) as containing
Propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-
Bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3chlorophenyl) propane and the like, and further bis (4-hydroxyphenyl) ether containing bis-O- as X, bis (4
-Hydroxy-3,5-dimethylphenyl) ether,
Bis (4-hydroxy-3,5-dichlorophenyl) ether, etc., and as X

[0016]

[Chemical 7] Including 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-)
Chlorophenyl) fluorene, 9,9-bis (4-hydroxy-3-bromophenyl) fluorene, 9,9-bis (4-hydroxy-3-fluorophenyl) fluorene, 9,9-bis (4-hydroxy-3-) Methoxyphenyl) fluorene, 9,9-bis (4-hydroxy-)
3,5-dimethylphenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dichlorophenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dibromophenyl) fluorene and the like, and further X Is absent from 4,4′-biphenol, 3,3′-biphenol and the like by a production method exemplified below.

Therefore, since the photosensitive resin material of the present invention is derived from the epoxy compound as described above, the oligomer represented by the above general formula (1) can be obtained as a slight mixture. There is no problem with the performance of. In the photosensitive resin material of the present invention, 50% or more, more preferably 70% or more, of the compound represented by the general formula (1) and having the repeating number p = 0 is present.

The polybasic acid or its acid anhydride capable of reacting with the above general formula (1) is, for example, maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, or anhydride. Hexahydrophthalic acid,
Methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, and biphenylethertetracarboxylic Examples thereof include aromatic polycarboxylic acid anhydrides such as acid dianhydride.

The (meth) acrylate compound obtained by reacting the epoxy (meth) acrylate represented by the general formula (1) with a polybasic acid or its acid anhydride is not necessarily limited to the above-mentioned ones. None of these can be used alone, or two or more of them can be used as a mixture.

Furthermore, the presence of an acid dianhydride as a polybasic acid or an acid anhydride thereof to be reacted with an epoxy (meth) acrylate provides a more suitable spacer material.
That is, the following general formulas (2) and (3)

[0021]

[Chemical 8]

[However, in the formulas (2) and (3), R
₁ , R ₂ , R ₃ and X are the same as those in formula (1), Y represents a dibasic acid or tribasic acid residue, Z represents an acid dianhydride residue, and q is 0 or It is an integer of 1 and the molar ratio (m / n) of the structural units is a ratio of 0/100 to 100/0].
A (meth) acrylate compound mainly composed of a unit structure represented by is more preferably used as the spacer material.

Although only the case of p = 0 in the general formula (1) is shown here for simplifying the formula, p =
In the cases of 1 to 10, the polybasic acid is added to the structure as in the general formulas (2) and (3). The term “mainly composed of” is used herein to mean that the units represented by the general formulas (2) and (3) in the acid addition product obtained by adding a polybasic acid to the general formula (1). It means that the structure occupies 50% by weight or more.

Examples of the acid anhydride compound capable of introducing the residue Y are, for example, maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendohydrate. Methylenetetrahydrophthalic acid, chlorendic anhydride, methyltetrahydrophthalic anhydride, trimellitic anhydride, etc. may be mentioned, and these may be used alone,
Further, two or more kinds may be used in combination, and further, the general formula (2)
In the above, only one of q = 0 and q = 1 may be used, or both may be mixed at an arbitrary ratio. Examples of the acid dianhydride capable of introducing the residue Z include aromatic polycarboxylic acid anhydrides such as pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, and biphenyltetracarboxylic dianhydride. These may be used alone or in combination of two or more. The acid anhydride and acid dianhydride may be used at any ratio, and in view of alkali developability, the acid anhydride (m) and the acid dianhydride (n) are preferably used. Molar ratio of (m
/ N) is a ratio of 1/99 to 90/10.

Regarding the molecular weight of the (meth) acrylate compound, a solution of 0.5 g of this compound in 100 ml of N-methylpyrrolidone has an inherent viscosity (η _inh ) of 0.1 dl / g or more measured at 30 ° C. It is preferably 0.15 dl / g or more, and gives favorable results as tack-free after the coating film is dried.

The spacer material in the present invention is suitable for forming a fine pattern by the exposure and alkali development operations as described above, but when the fine pattern is not required, the present material is formed by conventional screen printing. Even if a pattern is formed using, similar adhesiveness, transparency,
It is possible to provide a touch panel spacer having excellent surface hardness, flatness, moisture resistance, electrical insulation, heat resistance, and chemical resistance. In this case, the use ratio of the acid anhydride and the acid dianhydride is not limited.

The (meth) acrylate compound obtained by reacting the epoxy (meth) acrylate of the general formula (1) with a polybasic acid or its acid anhydride can be produced as follows. For example, first, a bisphenolfluorene type epoxy compound represented by the following general formula (4) obtained by the reaction of 9,9-bis (4-hydroxyphenyl) fluorene and epichlorohydrin, and the following general formula (5) A bisphenolfluorene type epoxy acrylate resin represented by the following general formula (6) is synthesized by reacting with (meth) acrylic acid represented by the following formula, and then the above-mentioned acid anhydride and ethyl cellosolve acetate, butyl cellosolve acetate. It is manufactured by heating in a cellosolve solvent such as. Regarding the reaction temperature, it is desirable to react quantitatively so that the acid anhydride becomes 1/2 mol per 1 mol of the OH group of the epoxy acrylate resin.
The temperature is 0 to 130 ° C, preferably 95 to 125 ° C. This reaction is the same for all compounds having the unit structures of the general formulas (2) and (3).

[0028]

[Chemical 9]

In the above general formulas (4) to (6), p = 0 in the general formula (1) for simplifying the formulas as in the general formulas (2) and (3). Although only the case of p = 1 to 10 is shown, it can be expressed similarly to the above general formulas (4) to (6). In the above general formulas (1) to (3), it is desirable to react the polybasic acid anhydride with the bisphenolfluorene type epoxy acrylate of the above general formula (6) during synthesis.
Due to this, excellent surface hardness, moisture resistance and adhesion are exhibited.

The photosensitive resin material of the present invention has the above-mentioned (meth)
Although it contains an acrylate compound, it contains a photopolymerization initiator for photocuring the acrylate compound. (Meta) of the present invention
The photopolymerization initiator and the sensitizer, which are the B component that cures the acrylate compound (A component), are not limited to the A component described above, but also a photopolymerizable (meth) acrylic monomer or (meth) compounded as necessary. ) It is also used as a polymerization initiator for a polymerizable unsaturated compound such as an acrylic oligomer. Examples of the component B used for such a purpose include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, p-tert-butylacetophenone. Benzophenones such as benzophenone, 2-chlorobenzophenone, p, p′-bisdimethylaminobenzophenone, benzoin ethers such as benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and the like, Benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-
Sulfur compounds such as isopropylthioxanthone and 2-
Ethyl anthraquinone, octamethyl anthraquinone,
Anthraquinones such as 1,2-benzanthraquinone and 2,3-diphenylanthraquinone, organic peroxides such as azobisisobutylnitrile, benzoyl peroxide, cumene peroxide, 2-mercaptobenzimidazole and 2-mercaptobenzoxazole , 2-
Examples thereof include thiol compounds such as mercaptobenzothiazole.

These compounds may be used in combination of two or more kinds. Further, a compound which does not act as a photopolymerization initiator by itself but which can increase the ability of the photopolymerization initiator by using it in combination with the above compound can be added. Examples of such compounds include tertiary amines such as triethanolamine, which are effective when used in combination with benzophenone.

The mixing ratio of the B component is such that the A component 1
0.1 to 30 parts by weight is suitable for 100 parts by weight,
When the blending ratio of the component B is less than 0.1 part by weight, the photopolymerization rate becomes slow and the sensitivity is lowered. On the other hand, when it exceeds 30 parts by weight, it is difficult for light to reach the substrate, and thus the substrate And the adhesiveness with the resin deteriorate.

Furthermore, in order to improve the moisture resistance, adhesion and electrical insulation stability of the cured product after photocuring and alkali development,
It is desirable to mix the compound (C component) having an epoxy group together with the above-mentioned (meth) acrylate compound and to carry out heat curing treatment. In the resin composition of the present invention, by performing heat treatment, adhesion to transparent electrodes such as glass and ITO (indium tin oxide) is improved, and moisture resistance, transparency, surface hardness, flatness, heat resistance, It is possible to form a touch panel spacer having excellent chemical resistance (although resistance to alkali is not required after heat curing in this application). The heating temperature and the heating time under the heat curing conditions are, for example, 80 to 200 ° C. and 10 to 120 minutes, respectively.

As the compound having an epoxy group which is the C component used for the above purpose, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin,
Epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin, phenyl glycidyl ether, p-butylphenol glycidyl ether, triglycidyl isocyanurate, diester Examples thereof include compounds having at least one epoxy group such as glycidyl isocyanurate, allyl glycidyl ether, and glycidyl methacrylate. The mixing ratio is 5 parts by weight for 100 parts by weight of the A component.
-50 parts by weight is preferred. Since the stitch structure is formed by the reaction between the carboxyl group contained in the component A and the epoxy group or the reaction between the epoxy groups during heating, the blending ratio of the component B to 100 parts by weight of the component A is less than 5 parts by weight. The effect of adding epoxy is not remarkable, but 5
If it exceeds 0 parts by weight, cracks are likely to occur during curing. Further, a small amount of an acid anhydride capable of reacting with the epoxy group may be added within a range that does not impair the properties of the resin composition of the present invention and a cured product thereof.

Further, in the photosensitive resin material of the present invention, in addition to the above-mentioned component A, a monomer or oligomer (component a) having an ethylenically unsaturated group capable of heat or photopolymerization is predetermined according to the purpose of use. Can be blended within the range. For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2
A monomer having a hydroxyl group such as ethylhexyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate,
Tetraethylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate (Meth) acrylic acid esters such as acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerol (meth) acrylate and the like can be mentioned. As the component a, any one of them can be used alone, or two or more can be used in combination.

It is necessary that the amount of component a used is within a range that does not impair the properties of the resin material of the present invention and its cured product.
It is used in the range of not more than 20 parts by weight, preferably not more than 20 parts by weight. If the amount used exceeds 50 parts by weight, tackiness after pre-curing will be a problem.

If necessary, the photosensitive resin material may include an epoxy group curing accelerator, a thermal polymerization inhibitor, a plasticizer,
Additives such as a leveling agent and an antifoaming agent can be appropriately mixed. Examples of the epoxy group curing accelerator include amine compounds, imidazole compounds, carboxylic acids, phenols, quaternary ammonium salts, and methylol group-containing compounds, and the like. It is possible to improve various properties such as heat resistance, solvent resistance, acid resistance, plating resistance, adhesion, electrical characteristics and hardness of the obtained resist film. Further, examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine and the like. Examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, tricresyl and the like. Examples of the defoaming agent and the leveling agent include silicon-based, fluorine-based, and acrylic compounds.

The touch panel spacer in the present invention is prepared by coating the photosensitive resin material of the present invention, that is, the spacer material, on the surface of the substrate as a solution and then drying the solvent by precure, and then obtaining the film thus obtained. It is formed by applying a negative film on the above, irradiating an actinic ray to cure the exposed portion, and eluting the unexposed portion with a weak alkaline aqueous solution.

Suitable solvents for preparing the solution of the spacer material in the present invention include ketones such as methyl ethyl ketone and methyl isobutyl ketone, and cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and cellosolve acetate. .

The method of applying the solution of the resin composition in the present invention to the substrate may be any of known methods such as a solution dipping method and a spray method, as well as a roller coater machine, a land coater machine and a spinner machine. Can be adopted. After applying the desired thickness by these methods,
A film is formed when the solvent is removed.

The substrate to be coated varies depending on the form used for the touch panel and the environment, but ITO on a glass or transparent film (for example, polycarbonate, polyethylene terephthalate, polyether sulfone, etc.),
A transparent electrode such as gold vapor-deposited or patterned is used.

The spacer material of the present invention is also cured by light or heat.
Light emitted from a lamp such as an ultra-high pressure mercury lamp, a high pressure mercury lamp or a metal halide lamp may be used.

As a developer suitable for alkali developing the spacer material of the present invention, for example, an aqueous solution of an alkali metal or alkaline earth metal carbonate, an aqueous solution of an alkali metal hydroxide, an inducing base such as diethanolamine, etc. Examples of the aqueous solution include, but especially sodium carbonate,
1-3% by weight of carbonates such as potassium carbonate and lithium carbonate
After development with a weakly alkaline aqueous solution of 10 to 50 ° C., preferably 20 to 40 ° C., a fine image can be precisely formed using a commercially available developing machine or ultrasonic cleaning machine.

The spacer material in the present invention is suitable for forming a fine pattern by the exposure and alkali development operations as described above. However, when the fine pattern is not required, this material is formed by conventional screen printing. Even if a pattern is formed by using the same, it is possible to provide a touch panel spacer excellent in adhesion, transparency, surface hardness, flatness, moisture resistance, electric insulation, heat resistance and chemical resistance.

The type of the touch panel in which the spacer of the present invention is used may be any method as long as the electrodes are opposed to each other through the spacer using two transparent conductive films or transparent conductive substrates. be able to. For example, as a configuration of a transparent touch panel, "manufacturing and application of transparent conductive film, first to thirteenth
Chapter "(published by CMC, supervised by Saburo Tabata, 1986)
Is exemplified. A spacer formed by patterning on the transparent conductive substrate or the transparent conductive film as described above is used as an insulating separator, and the transparent conductive films facing each other are laminated to form a transparent touch panel.
When the spacer material for a touch panel made of the photosensitive resin of the present invention is used, the coating film becomes tack-free after solvent drying, and it becomes possible to form a fine and precise pattern by contact exposure of a photomask, and develop with an alkaline aqueous solution. Is possible. Moreover, after curing, the touch panel has excellent surface hardness and transparency that cannot be achieved by conventional ones, and also has excellent adhesion to a substrate, flatness, acid resistance, alkali resistance, solvent resistance, electrical insulation, etc. Give a spacer for. Therefore, in the touch panel using this material, the basic key matrix can be made small and pen input can be performed, the number of keys and the arrangement can be flexibly obtained, and various input information can be dealt with.

[0046]

EXAMPLES The present invention will be specifically described below based on synthesis examples, examples and comparative examples. In the following, "part" means "part by weight". Moreover, about the synthesis | combination of the photopolymerizable unsaturated compound used by this invention, it showed in the synthesis examples 1-15.

Synthesis Example 1 In a 500 ml four-necked flask, 9,9-bis [4-
231 g of (2,3-epoxypropyl) phenyl] fluorene (epoxy equivalent 231, abbreviated as "bisphenolfluorene type epoxy resin" hereinafter) and 450 mg of triethylbenzylammonium chloride, 2,6-
100 mg of di-isobutylphenol, acrylic acid 7
2.0g was mixed and blown with air (25ml /
min. ) It melt | dissolved by heating at 90-100 degreeC. Next, the temperature of the solution remained turbid and gradually raised, and heated to 120 ° C. to completely dissolve the solution. The solution gradually became transparent and viscous and was stirred as it was. The acid value was measured, and heating and stirring were continued until the acid value was less than 2.0 mgKOH / g. It took 8 hours for the acid value to reach the target (acid value 0.8). And it cooled to room temperature and obtained the colorless and transparent solid.

Then, 2 kg of cellosolve acetate was added to 303 g of the bisphenol fluorene type epoxy acrylate resin [general formula (6)] obtained by the above reaction to form a solution, and then 38 g of 1,2,3,6-tetrahydrophthalic anhydride was added. And 80.5 g of benzophenone tetracarboxylic dianhydride and 1 g of tetraethylammonium bromide are mixed and gradually heated to react at 110 to 115 ° C. for 2 hours to obtain compound 1 (m / n = 50/50). It was The reaction of the acid anhydride was confirmed by the disappearance of the 1780 cm ^-1 peak in the IR spectrum. The obtained compound had an inherent viscosity of 0.3 dl / g (η _inh = 0.3).

Synthesis Example 2 Using 303 g of the bisphenol fluorene type epoxy acrylate resin prepared in Synthesis Example 1, 2 kg of cellosolve acetate was added to form a solution, and 121.6 g of 1,2,3,6-tetrahydrophthalic anhydride and benzophenone were added. 64.6 g of tetracarboxylic dianhydride and 1 g of tetraethylammonium bromide are mixed and gradually heated to 110
Reaction was carried out at 115 ° C. for 2 hours to give compound 2 (m / n = 80 /
20) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum as in Synthesis Example 1. The obtained compound had an inherent viscosity of 0.2 dl / g (η _inh = 0.2).

Synthesis Example 3 Using 303 g of the bisphenolfluorene type epoxy acrylate resin produced in Synthesis Example 1, 2 kg of cellosolve acetate was added to form a solution, and then 3.8 g of 1,2,3,6-tetrahydrophthalic anhydride and benzophenone. 153.8 g of tetracarboxylic dianhydride and 1 g of tetraethylammonium bromide are mixed and gradually heated to 110-1
Reaction was carried out at 15 ° C. for 2 hours to give compound 3 (m / n = 0.5 /
99.5) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound had an inherent viscosity of 0.3 dl / g (η _inh = 0.3).

Synthesis Example 4 Using 303 g of the bisphenol fluorene type epoxy acrylate resin prepared in Synthesis Example 1, 2 kg of cellosolve acetate was added to form a solution, and 144.4 g of 1,2,3,6-tetrahydrophthalic anhydride and benzophenone were added. Tetracarboxylic dianhydride 16.1 g and tetraethylammonium bromide 1 g were mixed and gradually heated to 110
Reaction was carried out at 115 ° C. for 2 hours to give compound 4 (m / n = 95 /
5) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.2 d.
It was 1 / g (η _inh = 0.2).

Synthesis Example 5 In place of the bisphenolfluorene type epoxy resin in Synthesis Example 1, 4,4'-di (2,3-epoxypropoxy) biphenyl (epoxy equivalent 153, hereinafter abbreviated as "biphenyl type epoxy resin"). A compound 5 (m / n = 50/50) reacted with an acid anhydride was obtained by the same procedure as in Synthesis Example 1 except that 153 g was used. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound had an inherent viscosity of 0.2 dl / g (η _inh = 0.2).

Synthesis Example 6 Instead of the bisphenolfluorene type epoxy resin in Synthesis Example 1, 163 g of bis [4- (2,3-epoxypropyl) phenyl] ketone (epoxy equivalent 163)
Compound 6 (m / n = 50/50) reacted with an acid anhydride was obtained by the same procedure as in Synthesis Example 1 except that was used. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.3 dl /
was g (η _inh = 0.3).

Synthesis Example 7 In place of the bisphenolfluorene type epoxy resin used in Synthesis Example 1, bis [4- (2,3-epoxypropyl) phenyl] sulfone (epoxy equivalent 181) 181
Compound 7 reacted with an acid anhydride by the same operation as in Synthesis Example 1 except that g was used (m / n = 50/50)
Got The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.3 dl /
was g (η _inh = 0.3).

Synthesis Example 8 Synthesis Example 1 was repeated except that 221 g of bis [4- (2,3-epoxypropyl) phenyl] hexafluoropropane (epoxy equivalent 221) was used in place of the bisphenolfluorene type epoxy resin in Synthesis Example 1. Compound 8 (m / n reacted with acid anhydride by operating in the same manner as
= 50/50) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound had an inherent viscosity of 0.4 dl / g (η _inh = 0.4).

Synthesis Example 9 Instead of the bisphenolfluorene type epoxy resin in Synthesis Example 1, bis [4- (2,3-epoxypropyl) phenyl] dimethylsilane (epoxy equivalent 163)
Compound 9 (m / n = 50) reacted with an acid anhydride by the same operation as in Synthesis Example 1 except that 163 g was used.
/ 50) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.
It was 2 dl / g (η _inh = 0.2).

Synthesis Example 10 156 g of bis [4- (2,3-epoxypropyl) phenyl] methane (epoxy equivalent 156) was used instead of the bisphenolfluorene type epoxy resin in Synthesis Example 1.
Compound 10 (m / n = 50/50) reacted with an acid anhydride by the same operation as in Synthesis Example 1 except that
Got The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.4 dl /
was g (η _inh = 0.4).

Synthesis Example 11 Instead of the bisphenolfluorene type epoxy resin in Synthesis Example 1, bis [4- (2,3-epoxypropyl) phenyl] propane (epoxy equivalent 170) 170
Compound 11 reacted with an acid anhydride (m / n = 50/5) was obtained by the same operation as in Synthesis Example 1 except that g was used.
0) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.4 d.
It was 1 / g (η _inh = 0.4).

Synthesis Example 12 In place of the bisphenolfluorene type epoxy resin in Synthesis Example 1, 4,4'-di (2,3-epoxypropyl) phenyl ether (epoxy equivalent 157) 157 g
Compound 12 (m / n = 50/50) reacted with an acid anhydride by the same operation as in Synthesis Example 1 except that
Got The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.3 dl /
was g (η _inh = 0.3).

Synthesis Example 13 303 g of the bisphenolfluorene type epoxy acrylate resin produced in Synthesis Example 1 was added to 2 kg of cellosolve acetate to prepare a solution, and then 76.0 g of 1,2,3,6-tetrahydrophthalic anhydride and an odor. 1 g of tetraethylammonium chloride is mixed, and the temperature is gradually raised to 95 to 10
Reaction was carried out at 0 ° C. for 4 hours to give compound 13 (m / n = 100 /
0) was obtained. The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound has an inherent viscosity of 0.15.
It was dl / g (η _inh = 0.15).

Synthesis Example 14 A reaction with an acid anhydride was carried out by the same procedure as in Synthesis Example 13 except that 153 g of biphenyl type epoxy resin (epoxy equivalent 153) was used in place of the bisphenol fluorene type epoxy resin in Synthesis Example 1. Compound 14
(M / n = 100/0) was obtained. Reaction of acid anhydride is IR
Confirmed by spectrum. The obtained compound had an inherent viscosity of 0.16 dl / g (η _inh = 0.1
6).

Synthesis Example 15 230 g of the bisphenolfluorene type epoxy acrylate resin produced in Synthesis Example 1 was added to 258 g of cellosolve acetate to form a solution, and then 18.24 g of trimellitic anhydride and 55.55 of biphenyltetracarboxylic dianhydride. 9 g and tetraethylammonium bromide 1 g were mixed, gradually heated to 110-115 ° C. and reacted for 2 hours to obtain compound 15 (m / n = 34/66). The reaction of the acid anhydride was confirmed by IR spectrum. The obtained compound had an inherent viscosity of 0.20 dl / g (η _inh = 0.20). The acid value was 100.

Examples 1 to 26 and Comparative Examples Component (A) obtained in Synthesis Examples 1 to 15 and component (B), if necessary, component (C), photopolymerizable acrylic monomer or oligomer and organic compound. The solvents were mixed in the proportions (parts by weight) shown in Tables 1 and 2 to prepare resist solutions of Examples 1 to 23 and 26 and Comparative Example, that is, photosensitive resin materials.

Next, these resist solutions were applied to a degreased and washed glass plate having a thickness of 1.2 mm to a thickness of about 2 μm and dried, and then a photomask was brought into close contact with the glass plate, and a 50
Illuminance 1 at a wavelength of 365 nm using a 0w high pressure mercury lamp
Ultraviolet rays of 0 mw / cm ² were irradiated for 20 seconds. After exposure,
It was developed with a 1 wt% sodium carbonate aqueous solution at 25 ° C. for 30 seconds to remove the unexposed portion of the coating film. After that, heat drying treatment was performed at 200 ° C. for 30 minutes using a hot air dryer. The resulting coating film surface was very smooth.

With respect to the obtained sample, the drying property of the coating film, the developability with respect to an alkaline aqueous solution, the exposure sensitivity, the coating film hardness, the adhesion to the substrate, the heat resistance and the chemical resistance (Examples 1 to 5)
In the case of, the alkali resistance was excluded), and the adhesion to Nesa glass (glass deposited with ITO) was also evaluated in the same manner. The results are shown in Table 3.

The resist solutions of Examples 24 and 25 (see Table 2) newly prepared in the same manner as in the above Example were degreased and washed with a screen printing machine to a glass plate having a thickness of 1.2 mm to a thickness of about 2 μm. 50 times after coating and drying
Illuminance 1 at a wavelength of 365 nm using a 0 W high pressure mercury lamp
After irradiating 0 mw / cm ² of ultraviolet rays for 20 seconds, a heat drying treatment was performed at 150 ° C. for 30 minutes using a hot air dryer. These coating films were also evaluated in the same manner (however, the evaluation of the developability of the coating film is excluded). The results are shown in Table 3.

[0067]

[Table 1]

[0068]

[Table 2]

[0069]

[Table 3]

As is clear from the results shown in Table 3, Example 1
Nos. 23 to 23 could achieve the desired physical properties. In Comparative Example 1, the amount of the photopolymerizable acrylic oligomer (dipentaerythritol hexaacrylate) compounded was large, and the tackiness remained in the coating film after precuring, which made the contact exposure difficult.

Various physical property data were measured under the following conditions. (1) Drying property of coating film The drying property of the coating film was evaluated according to JIS-5400.
The evaluation ranks are as follows. ◯: No tack is observed at all Δ: Slight tack is observed ×: Remarkably tack is observed

(2) Developability in Alkaline Aqueous Solution Development was carried out by immersing in a 1 wt% sodium carbonate aqueous solution for 30 seconds. After development, the resin was enlarged 40 times and the remaining resin was visually evaluated. The evaluation ranks are as follows. ◯: Good developability (no resist left on the glass) X: Poor developability (some resist left on the glass)

(3) Exposure sensitivity Kodak step tablet No. 2 (manufactured by Eastman Kodak, negative film having optical density steps of 0.15 and 21 steps) was adhered to the coating film, and a light amount of 200 mj / cm ² was irradiated using a 500 W high pressure mercury lamp. Next, the number of steps of the step tablet with respect to the weak alkaline aqueous solution described above was examined for this coating film (in this evaluation method, the higher the sensitivity, the greater the number of remaining steps).

(4) Coating film hardness After exposure and development, the coating film heated at 200 ° C. for 30 minutes was subjected to a hardness of 1 kg using a pencil hardness tester according to the test method of JIS-K5400. The highest hardness that does not scratch the coating film was displayed. The pencil used is "Mitsubishi High Uni."

(5) Adhesion with Substrate After exposure and development, a coating film heated at 200 ° C. for 30 minutes was used.
A cross cut was inserted so as to make at least 100 grids, and then a peeling test was performed using cellophane tape, and the state of peeling of the grids was visually evaluated. The evaluation ranks are as follows. ◯: No peeling was observed at all x: Peeling was observed even a little

(6) Heat resistance After exposure and development, a coating film which was heated at 200 ° C. for 30 minutes was used.
The state of the coating film was evaluated by placing it in an oven at 50 ° C. for 3 hours.
The evaluation ranks are as follows. ◯: There is no abnormality in the appearance of the coating film. X: There is peeling or coloring in the appearance of the coating film.

(7) Chemical resistance After exposure and development, a coating film heated at 200 ° C. for 30 minutes was
It was immersed in the following chemicals under the following conditions, and the appearance and adhesion after immersion were evaluated. Acid resistance 5% HCl for 24 hours Alkali resistance 5% NaOH for 24 hours Immersion 4% KOH 50 ° C.-10 min. 1% NaOH 80 ° C.-5 min. Solvent resistance NMP 40 ° C.-10 min. NMP 80 ° C.-5 min. (NMP: N-methyl-pyrrolidone)

(8) Transparency 400 to 8 before and after the heat resistance test and the chemical resistance test using the same glass plate as the one coated with the coating film as a reference.
The absorption spectrum at a wavelength of 00 nm was measured. ◯: 95% or more in all areas. X: Less than 95%.

Example 27 Using the compositions obtained in Examples 1 to 23 and 26 above,
As shown in FIG. 1, a transparent electrode (ITO) 4 is formed on the glass surface.
Is applied by spin coating to a thickness of 2.4 μm on a Nesa glass 2 having a size of 5 inches × 5 inches formed by vapor deposition, and a mask having a predetermined pattern is brought into close contact therewith for exposure. After development, post-baking is performed to form a spacer 1 having a line pattern with a line width of 20 μm and a spacing of 100 μm. Further, a transparent electrode (ITO) is formed on the resin film surface on the formed spacer 1.
Transparent conductive film having 5 deposited thereon [T-manufactured by: T-
COAT] 3 is installed such that its transparent electrode (ITO) 5 faces the transparent electrode (ITO) 4 of the Nesa glass 2, and the peripheral portions of these Nesa glass 2 and the transparent conductive film 3 are placed.
A room temperature curing type epoxy adhesive [Ciba Geigy Corp .: Araldite] was used to bond between the peripheral part of the test piece and the peripheral part to prepare a simple panel P for testing.

On the other hand, using the compositions of Examples 24 and 25, a line width of 100 was obtained by screen printing on Nesa glass 2.
A line pattern of μm and a space of 2 mm was printed and cured to form a spacer 1, and a simple panel P for test similar to the above was prepared.

A DC power supply 7 and a voltmeter 8 are provided on the simple panel P.
Was connected to the transparent conductive film 3 and the pen 6 was pressed from the transparent conductive film 3 side, the voltage change between the Nesa glass 2 and the transparent conductive film 3 at that time was measured, and the compositions of Examples 1 to 26 were used. It was confirmed that the simple panel P operates as a touch panel.

From the above results, the photosensitive resin material of the present invention is a touch panel spacer material excellent in surface hardness, transparency, adhesion, smoothness, chemical resistance, heat resistance, etc.
Further, it has been found that a touch panel having excellent performance capable of pen input can be provided by using this.

[0083]

When the spacer material for a touch panel made of the photosensitive resin of the present invention is used, the coating film becomes tack-free after solvent drying, and it becomes possible to form a fine pattern with good shape accuracy by contact exposure of a photomask, and ,
Development with an alkaline aqueous solution is possible. Moreover, after curing, the touch panel has excellent surface hardness and transparency that cannot be achieved by conventional ones, and also has excellent adhesion to a substrate, flatness, acid resistance, alkali resistance, solvent resistance, electrical insulation, etc. Give a spacer for. Therefore, in the touch panel using this material, the basic key matrix can be made small and pen input can be performed, the number of keys and the arrangement can be flexibly obtained, and various input information can be dealt with.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a simple panel for a test produced by using a spacer material for a touch panel of the present invention and a test method thereof.

[Explanation of symbols]

1 ... Spacer, 2 ... Nesa glass, 3 ... Transparent conductive film, 4, 5 ... Transparent electrode (ITO), 6 ... Pen, P ... Simple panel, 7 ... Power supply, 8 ... Voltmeter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Watanabe 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa, Nippon Steel Corporation Advanced Technology Research Laboratories

Claims (5)

[Claims] 1. The following general formula (1): [However, in the formula (1), R ₁ and R ₂ are hydrogen atoms,
It is either an alkyl group having 1 to 5 carbon atoms or a halogen atom, R ₃ is a hydrogen atom or a methyl group, and X is —CO.
_{-, - SO 2 -, -} C (CF 3) 2, -Si (CH 3)
_{2 -, - CH 2 -,} - C (CH 3) 2 - , -O-, Or absent, p is an integer of 0 to 10] and a photosensitizer containing a (meth) acrylate compound obtained by reacting an epoxy (meth) acrylate represented by the formula with a polybasic acid or an acid anhydride thereof. A spacer material for a touch panel, which is made of a conductive resin material. 2. A (meth) acrylate compound obtained by reacting an epoxy (meth) acrylate with a polybasic acid or an acid anhydride thereof is represented by the following general formulas (2) and (3): [However, in the formulas (2) and (3), R ₁ , R ₂ , R
₃ and X are the same as in formula (1), Y represents a dibasic acid or tribasic acid residue, Z represents an acid dianhydride residue, and q
Is an integer of 0 or 1, and the molar ratio of structural units (m / n)
Is a ratio of 0/100 to 100/0] as a main component, and 0.5 g of the compound is dissolved in 100 ml of N-methylpyrrolidone to measure the inherent viscosity (η _inh ) Is a compound of 0.1 dl / g or more, The spacer material for a touch panel according to claim 1. 3. (A) The (meta) according to claim 1 or 2.
0.1 to 30 parts by weight of (B) a photopolymerization initiator and / or a sensitizer with respect to 100 parts by weight of an acrylate compound,
(C) A spacer material for a touch panel, which comprises an alkali-developable photosensitive resin material containing 5 to 50 parts by weight of a compound having an epoxy group. 4. X in the general formula (1), (2) or (3) is A (meth) acrylate compound that is
The spacer material for a touch panel according to any one of 3 above. 5. A touch panel using a spacer for a touch panel, which is obtained by curing the spacer material according to claim 1.