KR20130077000A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE: A thermosetting resin composition is provided to effectively improve a crosslinking reaction even at low temperatures, thereby having excellent mechanical properties, chemical resistance, and adhesion to a substrate. CONSTITUTION: A thermosetting resin composition comprises a copolymer of an unsaturated carboxylic acid or an anhydride thereof, an epoxy group-containing unsaturated compound, and an olefin-based unsaturated compound; and a curing agent having an imidazole. The amount of the curing agent having an imidazole is 0.5-10 parts by weight per 100.0 parts by weight of the copolymer. The thermosetting resin composition includes 200 parts by weight of a polymerizable compound with an ethylenically unsaturated bond based on 100.0 parts by weight of the copolymer.

Description

Thermosetting resin composition

The present invention relates to a thermosetting resin composition, and more particularly, to a thermosetting resin composition capable of both high temperature and low temperature curing, which is suitable for forming a protective film which is provided to prevent deterioration of a substrate generated during a manufacturing process of an optical device such as a liquid crystal display device. It is about.

Optical devices such as liquid crystal display devices (LCDs) are subjected to harsh processing such as immersion treatment with organic solvents, acids, alkaline solutions, etc. during the manufacturing process, or localized high temperature heating of the surface by sputtering when forming wiring electrode layers. Will receive. Therefore, these devices tend to be subjected to a low temperature firing step in order to prevent deterioration during manufacturing, and in particular, a protective film may be provided on the surface thereof.

The protective film protects the colored layer and serves to planarize the color filter. Therefore, the protective film must withstand such harsh treatments and at the same time have excellent adhesion to the substrate or lower layer, and have high smoothness, surface hardness, transparency, and excellent heat resistance and light resistance without deterioration such as coloring, yellowing and whitening over a long period of time. do. Moreover, what is excellent in chemical-resistance, such as solvent resistance, acid resistance, and alkali resistance, water resistance, etc. is calculated | required. In addition, when applying such a protective film to the color filter of the color liquid crystal display device, it is preferable that the process proceeds at a low temperature rather than a high temperature.

The protective film composition is manufactured in the form of a curable resin composition so as to satisfy the above conditions, and largely classified into thermosetting and photocurable (photosensitive). When the patterning of the protective film is required, a photosensitive resin composition is required, but otherwise, a thermosetting resin composition is used, because it is convenient in the process and can increase the crosslinking density, thereby providing excellent mechanical properties and heat resistance.

Japanese Patent Application Laid-Open Nos. 2000-103937, 2000-119472 and 2000-143772 describe thermosetting resin compositions as compositions constituting a protective film. That is, the composition comprised from the acrylic resin containing a carboxyl group and an epoxy group, the polyfunctional monomer containing an ethylenically unsaturated group, and a thermal polymerization initiator is used.

However, when the protective film is prepared using these compositions, the mechanical properties are not excellent, and in particular, when the curing is performed at a low temperature, the adhesion to the substrate, the heat resistance, the chemical resistance, etc. are sharply dropped, and the device characteristics are often deteriorated.

The present invention effectively improves the crosslinking process at high temperature (200 to 250 ° C) as well as at low temperature (120 to 200 ° C), thereby providing a thermosetting resin composition having excellent mechanical properties, heat resistance chemical resistance, and adhesion to a substrate, and a protective film made of the composition. By improving the device life and brightness characteristics of the optical device.

One embodiment of the present invention is a copolymer of unsaturated carboxylic acid or anhydride thereof (a1), an epoxy group-containing unsaturated compound (a2), an olefinically unsaturated compound (a3), and; It is a thermosetting resin composition containing the hardening | curing agent [B] which has imidazole.

Another embodiment of the present invention is a thermosetting resin composition, wherein the curing agent [B] having imidazole is contained at 0.5 to 10 parts by weight based on 100 parts by weight of the copolymer [A].

According to another embodiment of the present invention, the thermosetting resin composition is a thermosetting resin composition comprising 200 parts by weight or less of a polymerizable compound [C] having an ethylenically unsaturated bond based on 100 parts by weight of the copolymer [A]. .

According to another embodiment of the present invention, the thermosetting resin composition is a thermosetting resin composition comprising 1 to 50 parts by weight of a curing agent [D] containing carboxylic acid or anhydride thereof, based on 100 parts by weight of the copolymer [A]. .

Another embodiment of the present invention is a protective film formed of the thermosetting resin composition.

The thermosetting resin of the present invention has excellent planarization and mechanical properties in both high temperature (200-250 ° C.) and low temperature (120-200 ° C.) curing processes, and in particular, has sufficient adhesiveness and heat resistance acid resistance and alkali resistance with a substrate in low temperature curing. A protective film can be manufactured and the thermosetting resin composition which is highly suitable as a protective film formation material for optical devices can be provided.

According to one embodiment of the present invention, a copolymer of unsaturated carboxylic acid or anhydride thereof (a1), an epoxy group-containing unsaturated compound (a2), an olefinically unsaturated compound (a3), and; It is providing the thermosetting resin composition containing the hardening | curing agent [B] which has imidazole.

Hereinafter, the present invention will be described in more detail.

The said copolymer [A] is obtained by the conventionally well-known polymerization method, ie, compound (a1), (a2), and (a3) can be synthesize | combined by performing radical polymerization in presence of a polymerization initiator in a solvent.

The copolymer [A] preferably contains 5 to 40% by weight, more preferably 10 to 30% by weight of the structural unit derived from the compound (a1). When this structural unit is less than 5 weight%, the heat resistance, chemical resistance, and surface hardness of the protective film manufactured later tend to fall, and when it exceeds 40 weight%, there exists a problem that storage safety falls. Examples of the compound (a1) include monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid; Dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid and itaconic acid; And anhydrides of these dicarboxylic acids. One of these dicarboxylic acids may be used alone, or two or more dicarboxylic acids may be used in combination. Among them, acrylic acid, methacrylic acid, maleic anhydride and the like are mainly used because of their excellent copolymerization reactivity and heat resistance and easy availability.

In addition, the copolymer [A] preferably contains 10 to 70% by weight, more preferably 20 to 60% by weight of the structural unit derived from the compound (a2). When this structural unit is less than 10 weight%, the heat resistance and surface hardness of the protective film produced later tend to fall, and when it exceeds 70 weight%, storage safety tends to fall. Examples of the compound (a2) include glycidyl acrylate, glycidyl methacrylate, α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylate glycidyl, and acrylic acid-3. , 4-epoxy butyl, methacrylic acid-3,4-epoxy butyl, acrylic acid-6,7-epoxy heptyl, methacrylic acid-6,7-epoxy heptyl, α-ethyl acrylic acid-6,7-epoxy heptyl, o It is used alone or in combination of two or more selected from -vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, and p-vinyl benzyl glycidyl ether to improve the copolymerization reactivity and the heat resistance and hardness of the resulting protective film. It is preferably used in that point.

The copolymer [A] preferably contains 10 to 70% by weight, more preferably 20 to 50% by weight of the structural unit derived from the compound (a3). When this structural unit is less than 10 weight%, storage stability tends to fall, and when it exceeds 70 weight%, the heat resistance and surface hardness of the protective film produced later tend to fall. Examples of the compound (a3) include methacrylic acid alkyl esters such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate and t-butyl methacrylate; Acrylic acid alkyl esters such as methyl acrylate and isopropyl acrylate; Methacrylic acid cycloalkyl esters such as cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate and isoboroyl methacrylate; Acrylic acid cycloalkyl esters such as cyclohexyl acrylate, 2-methyl cyclohexyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate and isoboroyl acrylate; Methacrylic acid aryl esters such as phenyl methacrylate and benzyl methacrylate; Acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate; Dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate and diethyl itaconic acid; Hydroxy alkyl esters such as 2-hydroxy ethyl methacrylate and 2-hydroxy propyl methacrylate; And styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, vinyl toluene, p-methoxy styrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, Vinyl acetate, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, or a combination of two or more thereof. Among them, styrene, t-butyl methacrylate, dicyclopentenyl methacrylate, p-methoxy styrene, 2-methyl cyclohexyl acrylate, 1,3-butadiene and the like are preferred from the viewpoint of copolymerization reactivity and heat resistance.

The copolymer [A] used in the present invention has a carboxyl group and / or a carboxylic anhydride and an epoxy group, and can be easily cured by heating without using a special curing agent, but the above-mentioned curable compound [B] In the case of using, the crosslinking density can be sufficiently increased.

Although the molecular weight of copolymer [A] is not specifically limited, It is suitably selected according to the thickness of the film | membrane formed, the solution coating conditions of a curable composition, the objective, etc .. It is preferable that the number average molecular weight of copolymer [A] exists in the range of 3,000-100,000 in consideration of the surface smoothness of the protective film manufactured later, More preferably, it is 3,000-50,000.

As a solvent used for the synthesis | combination of copolymer [A], Alcohol, such as methanol and ethanol; Ethers such as tetrahydrofuran, diethylene glycol dimethyl ether and diethylene glycol diethyl ether; One or a combination of two or more selected from propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, and propylene glycol butyl ether acetate is preferred.

As a polymerization initiator used for the synthesis | combination of a copolymer [A], what is generally known as a radical polymerization initiator can be used. Azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobis- (4-methoxy- Dimethylvaleronitrile); and the like; Organic peroxides such as benzoyl peroxide, t-butyl peroxypivalate, and 1,1'-bis- (t-butylperoxy) cyclohexane; And hydrogen peroxide. When a peroxide is used as a radical polymerization initiator, the peroxide can be used as a redox type initiator together with a reducing agent.

The curing agent [B] containing the imidazole serves to improve the crosslinking density by activating the crosslinking reaction of the polymerizable compound [C] at a low temperature according to its initiation temperature, thereby improving surface hardness, heat resistance stability and adhesion to the substrate. It is excellent and especially has acid resistance and alkali resistance. The curing agent [B] having imidazole has various onset temperatures and half-lives depending on the production method thereof, and it is particularly preferable to select a product having good storage stability.

The curing agent having imidazole varies in molecular weight depending on its preparation method. However, when the structure is complex and the molecular weight is high, it is easier to use a product having a lower molecular weight because of poor solubility.

Specific examples of the curing agent [B] having such an imidazole include 2MZ, 2MZ-P, C11Z, 2E4MZ, 2PZ, 2PZ-PW, 2P4MZ, 1B2MZ, 1B2PZ, 1.2DMZ, 2MZ-CN, and 2E4MZ-CN, manufactured by Shikoku Corporation. C11Z-CN, 2PZ-CN, C1Z-CNS, 2PZ-CNS, 2PZCNS-PW, 2MZ-A, 2MZA-PW, C11Z-A, 2E4MZ-A, 2MA-OK, 2MAOK-PW, 2PZ-OK, 2MZ- OK, 2PHZ, 2PHZ-PW, 2P4MHZ, 2P4MHZ-PW, TBZ, 1B2PZ-HBR, SFZ, 2MZL-F, 2PZL, etc. are mentioned.

It is preferable that the hardening | curing agent [B] which has the said imidazole contains 0.5-10 weight part with respect to 100 weight part of copolymers [A]. When the content of the curing agent [B] having imidazole is less than 0.5 part by weight based on 100 parts by weight of the copolymer [A], it is difficult to obtain a protective film having a sufficiently high crosslink density at low temperature as well as at high temperature, and various resistances of the protective film are lowered. There is a problem that can be. Moreover, when it exceeds 10 weight part, the surface of the protective film obtained by inferior melting | dissolving power or a compatibility fall will become nonuniform, As a result, a protective film will look cloudy, and property will become unstable or adhesiveness will fall easily. In addition, there is a problem that the storage stability is sharply reduced.

The thermosetting resin composition according to the present invention may further include a polymerizable compound [C] having an ethylenically unsaturated bond.

The polymerizable compound [C] having an ethylenically unsaturated bond is preferable from the viewpoint that the monofunctional, bifunctional or trifunctional or higher (meth) acrylate has good polymerizability and the heat resistance and surface hardness of the protective film obtained later are improved. .

As said monofunctional (meth) acrylate, 2-hydroxy ethyl (meth) acrylate, carbitol (meth) acrylate, isobornyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 2- (meth) acryloyloxy ethyl 2-hydroxy propyl phthalate etc. are mentioned.

As said bifunctional (meth) acrylate, ethylene glycol (meth) acrylate, 1, 6- hexanediol (meth) acrylate, 1, 9- nonanediol (meth) acrylate, propylene glycol (meth) acryl The rate, tetraethylene glycol (meth) acrylate, bisphenoxy ethyl alcohol fluorene diacrylate, etc. are mentioned.

Examples of the above (meth) acrylate having three or more functional groups include (meth) acrylic esters such as trishydroxyethylisocyanurate tri (meth) acrylate, trimethylpropane tri (meth) acrylate, pentaerythritol tri Tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like.

It can be used as a polymeric compound [C] by 1 type or in combination of 2 or more types selected from such monofunctional, bifunctional, or trifunctional or more than (meth) acrylate.

The said polymeric compound [C] is 200 weight part or less with respect to 100 weight part of copolymers [A], Preferably it is 120 weight part or less, It is good to contain 10 to 120 weight part more preferably. When content of the said polymeric compound [C] exceeds 200 weight part with respect to 100 weight part of copolymers [A], the adhesiveness of the protective film obtained will fall easily.

The thermosetting resin composition according to the present invention may optionally include a curing agent [D] comprising a carboxylic acid or an anhydride thereof, optionally together with the above-mentioned copolymer [A], a curing agent [B] having an imidazole, and a polymerizable compound [C]. have.

Curing agent [D] containing the said carboxylic acid or its anhydride is a component which causes hardening reaction with the said [A] component. Examples of the carboxylic anhydride include 4-methyltetrahydrophthalic anhydride, methylnadic acid anhydride, pyromellitic anhydride, trimellitic anhydride, phthalic anhydride, and the like. These anhydrides may be chemically modified and used.

The curing agent [D] is preferably 1 to 50 parts by weight, preferably 5 to 20 parts by weight based on 100 parts by weight of the copolymer [A], but the content thereof is less than 1 part by weight based on 100 parts by weight of the copolymer [A]. In the case, it is difficult to obtain a protective film having a sufficiently high crosslinking density and the various resistances of the protective film may be lowered. Moreover, when it exceeds 50 weight part with respect to 100 weight part of copolymers [A], a large amount of unreacted substance will remain easily in the film | membrane of the protective film obtained, As a result, the property of a protective film will become unstable or adhesiveness will fall easily.

In addition, the thermosetting resin composition of the present invention may further include at least one kind selectively from the group consisting of a surfactant, an adhesion aid, a thermal radical polymerization initiator, an antioxidant, and an ultraviolet absorber as other additives [E].

Examples of the surfactant include FC-129, FC-170C and FC-430 manufactured by 3M Company. The surfactant may be fluorine or silicon surfactant. This can be used in an amount of 5 parts by weight or less, more preferably 2 parts by weight or less, based on 100 parts by weight of the copolymer [A]. When using surfactant more than 5 weight part with respect to 100 weight part of copolymers [A], there exists a problem which foams easily at the time of application | coating.

The adhesive aid serves to improve adhesion with the substrate. As the adhesion aid, a functional silane coupling agent is preferably used. Examples thereof include trimethoxysilylbenzoic acid,? -Isocyanate propyltriethoxysilane,? -Glycidoxypropyltrimethoxysilane, and the like. It may be used in an amount of 50 parts by weight or less, more preferably 20 parts by weight or less, based on 100 parts by weight of the copolymer [A], but an adhesive aid is used in excess of 50 parts by weight based on 100 parts by weight of the copolymer [A]. When it does, heat resistance will fall easily.

On the other hand, the thermal radical polymerization initiator may be used to accelerate the crosslinking reaction of the polymerizable compound [C], and generally known as a radical polymerization initiator may be used, and may be used for the polymerization of the copolymer [A]. A polymerization initiator can be used. The thermal radical polymerization initiator is contained in an amount of 20 parts by weight or less, more preferably 15 parts by weight or less based on 100 parts by weight of the copolymer [A]. When the thermal radical polymerization initiator exceeds 20 parts by weight, the heat resistance and planarization property of the protective film obtained later are likely to be lowered.

The thermosetting resin composition of the present invention is prepared by dissolving the curing agent [D] and other additives [E] selectively with a copolymer [A], a curing agent [B] having an imidazole, and a polymerizable compound [C]. can do. The solvent used at this time does not react with any component. For example, a solvent used for the polymerization of the copolymer [A] can be used. Of these solvents, diethylene glycol dimethyl ether, diethylene glycol diethyl ether and propylene glycol methyl ether are preferable from the viewpoints of solubility, reactivity, Acetate is preferred. It is also possible to use a high boiling point solvent together with the above solvent. Examples of the high boiling point solvent include N, N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, And the like. When such a high boiling point solvent is used in combination, the mixing ratio with the solvent is preferably "(the above solvent): (high boiling point solvent) = 100: 0 to 40".

It is preferable that the total solid content of the solution containing [A], [B], [C], [D] and [E] and the solvent is 10 to 40% by weight, and when the solid content is less than 10% by weight, the coating The thickness cannot be sufficiently obtained, and the storage stability is lowered when the solid content is 40% by weight or more.

The thermosetting resin composition mixed as described above may be used after filtering using a filter having a diameter of about 0.1 ~ 5㎛.

The thermosetting resin composition of this invention can form a protective film by the following method, for example.

After applying a thermosetting resin composition to a board | substrate, removing a solvent and forming the coating film of a thermosetting resin composition, it can heat-process and can obtain a protective film.

As the substrate, glass, quartz, silicon, resin, or the like can be used, and examples of the resin include a ring-opening polymer of polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, polyimide and cyclic olefin, Hydrogenated products, and the like.

The method of applying the thermosetting resin composition solution is not particularly limited, and for example, a spray method, a roll coating method, a spin coating method, or the like can be used.

The removal of the solvent is preferably performed by a heat treatment (preliminary firing). Although the conditions of such preliminary baking differ with kinds, ratios, etc. of each component of a composition solution, it is preferable to bake about 0.5 to 20 minutes at 60-120 degreeC.

Subsequent heat treatment, the treatment temperature at this time can be treated for 5 to 100 minutes at 150 ~ 250 ℃ to produce a protective film for an optical device.

The thickness of the protective film formed as described above is preferably 0.1 to 6 µm, and when the unevenness is formed on the substrate forming the protective film, the value should be understood as the value at the top of the unevenness.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

<Production Example>

2,2′-azo as a polymerization initiator based on 100 parts by weight of the total amount of monomers (compound (al), compound (a2), compound (a3)) used in the synthesis of the copolymer in a reaction vessel equipped with a cooling tube and a stirrer. 5 parts by weight of bis isobutyronitrile and 200 parts by weight of diethylene glycol dimethyl ether were added as a solvent. Subsequently, 20 parts by weight of styrene, 30 parts by weight of methacrylic acid, 40 parts by weight of glycidyl methacrylate, and 10 parts by weight of dicyclopentenyloxyethyl methacrylate were added thereto, followed by nitrogen replacement, and stirring was gradually started. The temperature of the solution was raised to 80 ° C. and maintained at this temperature for 4 hours to obtain a polymer solution containing the copolymer [A1]. Solid content concentration of the obtained copolymer solution was 33.0 weight%.

&Lt; Example 1 >

1 part by weight of 2PZ-CN manufactured by Shikoku Co., Ltd. as a curing agent [B] having imidazole based on 100 parts by weight of the copolymer [A1] obtained in the above Production Example and 100 parts by weight of the copolymer [A1], and 0.1 weight part of FC430 (fluorine type surfactant) by 3M as a surfactant was mixed, and it melt | dissolved in 100 g of propylene glycol methyl ether acetates, and 10 g of diethylene glycol dimethyl ethers, and made solid content concentration 25 weight%. Then, it filtered by the filter of 0.45 micrometers of pore diameters, and manufactured the thermosetting resin composition solution.

Using a spin coater on the glass substrate, the thermosetting resin composition solution was applied to a film thickness of 2 μm, and then fired in a clean oven at 150 ° C., 180 ° C., 200 ° C., and 230 ° C. for 30 minutes, respectively, to form a protective film on the glass substrate. Formed.

<Example 2>

Thermosetting resin in the same manner as in Example 1, except that 1 part by weight of 2PZ manufactured by Shikoku Corporation as a curing agent [B] having imidazole and 0.1 part by weight of FC-430 (fluorine-based surfactant) manufactured by 3M Corporation as a surfactant was mixed. The composition solution was prepared, and a protective film was formed on the glass substrate in the same manner.

<Example 3>

A thermosetting resin composition solution was prepared in the same manner as in Example 1, except that 50 parts by weight of pentaerythritol tetramethacrylate as the polymerizable compound [C] and 10 parts by weight of trimellitic anhydride were further mixed as the curing agent [D]. A protective film was formed on the glass substrate in the same manner.

&Lt; Comparative Example 1 &

A thermosetting resin composition solution was prepared in the same manner as in Example 3, except that the curing agent [B] having imidazole was not used, and a protective film was formed on the glass substrate by the same method.

Comparative Example 2

A thermosetting resin composition solution was prepared in the same manner as in Example 3, except that 150 parts by weight of pentaerythritol tetramethacrylate was used as the polymerizable compound [C] without using a curing agent [B] having an imidazole. A protective film was formed on the glass substrate in the same manner.

Evaluation method for the protective film used in the present invention is as follows, the evaluation results for the protective film prepared in Examples and Comparative Examples are shown in Table 1.

(1) Adhesiveness

According to a checkerboard tape method, 11 lines of cuts having a spacing of 1 mm were cut out to a depth of the upper surface of the glass substrate using a cutter knife using a cutter knife, After forming a checkerboard pattern, an adhesive tape (Elcometer Co., Part Number K0001539M001) was placed on a checkerboard pattern and peeled off. The number of peeled checkerboard patterns was measured, and the adhesion of the cured film was evaluated according to the following criteria.

○: Number of peeled checkered patterns No more than 5

B: Number of peeled checkered patterns 6 to 49

X: Number of peeled checkered patterns 50 or more

(2) Surface hardness

The cured film was subjected to the pencil hardness test according to the pencil hardness method (test standard: ASTM D3363) to evaluate the surface hardness.

(3) Transparency

The transmittance of the protective film was measured at 400 to 700 nm using a spectrophotometer (Shimadzu Corporation, UV-3101), and the transparency of the protective film was evaluated according to the following criteria.

○: Minimum transmittance exceeded 95%

?: Minimum transmittance: 90 to 95%

×: Minimum transmittance less than 90%

(4) UV resistance

The transmittance of the protective film was measured at 400 to 700 nm using a spectrophotometer (UV-3101PC, manufactured by Shimadzu Corporation). Separately, the cured film was irradiated with UV (wavelength: 254 nm, irradiation amount: 200 mJ / cm 2), and the transmittance was measured by the same method. From each transmittance, the UV resistance of the protective film was evaluated according to the following criteria.

?: Transmission spectrum change within 1%

X: Change in transmission spectrum exceeds 1%

(5) Heat resistance (degree of yellowing)

The transmittance of the protective film was measured at 400 to 700 nm using a spectrophotometer (UV-3101PC, manufactured by Shimadzu Corporation). Separately, the cured film was heated for 60 minutes at 240 degreeC clean oven, and the transmittance | permeability was measured by the same method. The heat resistance of the protective film was evaluated from each transmittance by the following criteria.

○: Transmission spectrum change within 1% (no yellowing phenomenon)

X: Change in transmission spectrum exceeding 1% (yellowing phenomenon)

(6) Acid resistance

After the glass substrate on which the protective film was formed was immersed in a 25 wt% aqueous hydrochloric acid solution for 30 minutes at 30 ° C., the appearance change of the protective film was observed to evaluate the acid resistance of the protective film.

(7) Alkalinity

After the glass substrate on which the protective film was formed was immersed in a 10 wt% sodium hydroxide aqueous solution for 30 ° C. for 60 minutes, the appearance change of the protective film was observed to evaluate the alkali resistance of the protective film.

division Curing temperature (℃) Adhesiveness Surface hardness Transparency UV resistance Heat resistance Acid resistance Alkali resistance Example 1 150 △ 3H ○ ○ ○ Slightly turbid Slightly turbid 180 ○ 4H ○ ○ ○ No change No change 200 ○ 5H ○ ○ ○ No change No change 230 ○ 5H ○ ○ ○ No change No change Example 2 150 ○ 4H ○ ○ ○ No change No change 180 ○ 5H ○ ○ ○ No change No change 200 ○ 5H ○ ○ ○ No change No change 230 ○ 5H ○ ○ ○ No change No change Example 3 150 ○ 5H ○ ○ ○ No change No change 180 ○ 5H ○ ○ ○ No change No change 200 ○ 5H ○ ○ ○ No change No change 230 ○ 5H ○ ○ ○ No change No change Comparative Example 1 150 × 1H × × × muddiness muddiness 180 × 2H × × × muddiness muddiness 200 × 3H × × × muddiness muddiness 230 × 3H × × × muddiness muddiness Comparative Example 2 150 × 1H × × × muddiness muddiness 180 × 2H × × × muddiness muddiness 200 × 3H × × × muddiness muddiness 230 × 3H × × × muddiness muddiness

As shown in Table 1, when forming the color filter protective film on the substrate, when using the thermosetting resin of the present invention, the surface hardness, planarization, UV resistance and heat resistance under various curing temperature conditions in particular compared to the comparative example You can see the excellent. Therefore, when the thermosetting resin of the present invention is applied to a protective film, it can be seen that it can be applied to low temperature curable devices while satisfying the characteristics as a protective film, thereby providing a protective film having excellent mechanical properties in various optical device processes.

Claims (5)

A copolymer [A] of an unsaturated carboxylic acid or an anhydride thereof (a1), an epoxy group-containing unsaturated compound (a2), an olefinically unsaturated compound (a3), and;
The thermosetting resin composition containing the hardening | curing agent [B] which has imidazole. The thermosetting resin composition according to claim 1, wherein the curing agent [B] having imidazole is contained at 0.5 to 10 parts by weight based on 100 parts by weight of the copolymer [A]. The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition contains not more than 200 parts by weight of a polymerizable compound [C] having an ethylenically unsaturated bond based on 100 parts by weight of the copolymer [A]. The thermosetting resin composition according to claim 1, wherein the thermosetting resin composition comprises 1 to 50 parts by weight of a curing agent [D] containing carboxylic acid or anhydride thereof, based on 100 parts by weight of the copolymer [A]. The protective film for optical devices formed from the thermosetting resin composition of any one of Claims 1-4.