TW201832008A - Negative photosensitive resin composition having excellent properties including sensitivity, flatness, resolution and residue film rate - Google Patents

Abstract

This invention discloses a negative photosensitive resin composition which has excellent properties such as sensitivity, flatness, resolution and residue film rate, and particularly the formation process of white sub-pixels and interlayer insulating films in RGBW(Red, Green, Blue, White) are simultaneously performed, which not only simplify the pattern forming method, but also be effectively used for a display having high brightness and low power consumption. The negative photosensitive resin composition includes an acrylic copolymer; a polyfunctional urethane-based methacrylate compound represented by the following chemical formula (1); a radical photoinitiator; and a solvent, wherein in the chemical formula (1), D is a hydrocarbon group having 1 to 20 carbon atoms, and n and m are each independently an integer of 0 to 2.

Description

Negative photosensitive resin composition

The present invention relates to a negative photosensitive resin composition, and more specifically relates to the following negative photosensitive resin composition, which has excellent characteristics such as sensitivity, planarization, resolution, and residual film rate, especially in the RGBW structure. The white sub-picture element and the interlayer insulating film forming process replace the conventional process of filling the columnar spacer, which not only can simplify the pattern forming method, but also can be effectively used for displays with high brightness and low power consumption.

In general, as modern society is transformed into information society, the importance of liquid crystal display device elements, which is one of the information display devices, is gradually increasing. Although a liquid crystal device generally used has advantages such as miniaturization, weight reduction, thinness, and low power consumption, it has the disadvantage of being expensive in terms of price.

In addition, a recent trend in the display field is to realize large-sized and high-resolution displays. Conventionally used displays have a structure in which an array substrate in which thin-film transistors are arranged and a color filter substrate in which red, green, and blue filter layers are formed are bonded to each other via a liquid crystal. In this case, because The three sub-picture elements composed of red, green, and blue filter layers have a unit picture element structure, so there are disadvantages of low light transmittance and low brightness per unit picture element. For high-resolution mode, each sub picture The size of the element becomes smaller. In this case, there is a disadvantage that high resolution cannot be achieved due to low brightness. In particular, through the development of the RGBW structure, the market for 43-65-inch ultra-high-definition (UHD) panels needs to continue to increase. This RGBW structure panel has high resolution, high brightness, Low power consumption, and has considerable advantages in cost competitiveness. Therefore, a column spacer (CS) manufacturing process is not needed. The interlayer insulation film process can effectively fill white. Flattening properties of the sub-element space.

In this case, it is necessary to increase the content of the polyfunctional acrylic oligomer and ethylenically unsaturated polyfunctional monomer in the composition. If the content of the above oligomer and monomer is increased, there is a halftone (Half Tone). The high light curing degree of the region may cause the problem of reduced hole margin. Therefore, there is a need to develop an interlayer insulating film that has both high planarization characteristics and excellent hole margin characteristics with high resolution.

Problems to be solved

Therefore, an object of the present invention is to provide a negative-type photosensitive resin composition which significantly improves sensitivity, planarization, resolution, and residual film by including a polyfunctional urethane-based methacrylate having a specific structure. And other characteristics, and by introducing the methyl group of methacrylate, the steric hindrance of the monomer in the composition is induced, the initial reaction (cross-linking degree) based on light is adjusted, and the half tone is controlled ) Area of light curing, hole margin is better.

Problem solving

In order to achieve the above object, the present invention provides a negative photosensitive resin composition including: an acrylic copolymer; a polyfunctional urethane-based methacrylate compound represented by the following Chemical Formula 1; a radical photoinitiator; As well as solvents.

Chemical formula 1

In the above Chemical Formula 1, D is a hydrocarbon group having 1 to 20 carbon atoms, and n and m are each independently an integer of 0 to 2.

Invention effect

The negative photosensitive resin composition of the present invention has excellent characteristics such as sensitivity, flatness, resolution, and residual film rate. In particular, it does not require a columnar spacer (CS) process, and can be filled at one time through the interlayer insulating film process. The free space of the white (White) sub-pixels with a full RGBW structure is suitable for a liquid crystal display device with an RGBW structure which is advantageous for high brightness and low power consumption.

Problems to be solved

Therefore, an object of the present invention is to provide a negative-type photosensitive resin composition which significantly improves sensitivity, planarization, resolution, and residual film by including a polyfunctional urethane-based methacrylate having a specific structure. And other characteristics, and by introducing the methyl group of methacrylate, the steric hindrance of the monomer in the composition is induced, the initial reaction (cross-linking degree) based on light is adjusted, and the half tone is controlled ) Area of light curing, hole margin is better.

Problem solving

In order to achieve the above object, the present invention provides a negative photosensitive resin composition including: an acrylic copolymer; a polyfunctional urethane-based methacrylate compound represented by the following Chemical Formula 1; a radical photoinitiator; As well as solvents.

Chemical formula 1

In the above Chemical Formula 1, D is a hydrocarbon group having 1 to 20 carbon atoms, and n and m are each independently an integer of 0 to 2.

Invention effect

The negative photosensitive resin composition of the present invention has excellent characteristics such as sensitivity, flatness, resolution, and residual film rate. In particular, it does not require a columnar spacer (CS) process, and can be filled at one time through the interlayer insulating film process. The free space of the white (White) sub-pixels with a full RGBW structure is suitable for a liquid crystal display device with an RGBW structure which is advantageous for high brightness and low power consumption.

The invention is explained in more detail with reference to the following figures.

The negative photosensitive resin composition of the present invention includes: (a) an acrylic copolymer; (b) a polyfunctional urethane-based methacrylate compound; (c) a radical photoinitiator; and (d) a solvent .

When the acrylic copolymer (equivalent to (a)) is developed, it plays a role of easily forming a predetermined pattern that does not cause scum, and it is possible to use a conventionally used high-sensitivity photosensitive resin composition. For the molecule, for example, an acrylic copolymer can be used. The acrylic copolymer uses (i) an unsaturated carboxylic acid, an unsaturated carboxylic anhydride, a mixture thereof, and the like, and (ii) an olefinic unsaturated compound as a monomer. It is obtained by performing a free radical reaction and synthesis in the presence of a solvent and a polymerization initiator, and then removing unreacted monomers through a process of precipitation, filtration, and vacuum drying. The above-mentioned acrylic copolymer has a weight average molecular weight (Mw) of 3,000 to 30,000, specifically 3500 to 25,000, and more specifically 4,000 to 20,000. When the weight average molecular weight (Mw) is less than 3000, the developability, the residual film rate, and the like can be reduced, and the pattern development and heat resistance can be reduced. When it is more than 30,000, the pattern development can be reduced. The weight average molecular weight is a converted weight average molecular weight (Mw) calculated using polystyrene as a standard material (the same applies hereinafter).

As the unsaturated carboxylic acid, unsaturated carboxylic anhydride, and mixtures thereof, unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid may be used alone or in combination of two or more; maleic acid, fumaric acid, citraconic acid, medium Unsaturated dicarboxylic acids such as fumaric acid and itaconic acid; or their unsaturated dicarboxylic anhydrides, etc., specifically, when acrylic acid, methacrylic acid, maleic anhydride, and mixtures thereof are used, the copolymerization reactivity and The developer is more effective in the solubility of an alkaline aqueous solution.

As the olefin-based unsaturated compound, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, methyl acrylate, and isopropyl acrylate can be used. Ester, cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, dicyclopentenyl acrylate, dicyclopentyl acrylate, dicyclopentenyl methacrylate, dicyclopentyl methacrylate, 1-adamantyl acrylate, 1-adamantyl methacrylate, dicyclopentyloxyethyl methacrylate, isobornyl methacrylate, cyclohexyl acrylate, 2-methylcyclohexyl acrylate , Dicyclopentyloxyethyl acrylate, isobornyl acrylate, phenyl methacrylate, phenyl acrylate, benzyl acrylate, 2-hydroxyethyl methacrylate, styrene, o-methylstyrene, m-formyl Styrene, p-methylstyrene, vinyl toluene, p-methoxystyrene, 1,3-butadiene, isoprene, or 2,3-dimethyl 1,3-butadiene, Glycidyl acrylate, glycidyl methacrylate, α-ethyl acrylic acid Glycidyl ester, α-n-propyl glycidyl acrylate, α-n-butyl glycidyl acrylate, acrylic acid-β-methyl glycidyl ester, methacrylic acid-β-methyl glycidyl ester, acrylic acid-β- Ethyl glycidyl ester, β-ethyl glycidyl methacrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutyl methacrylate, -6,7-epoxy Heptyl, -6,7-epoxyheptyl methacrylate, α-ethylacrylic-6,7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, or The vinyl benzyl glycidyl ether, 3,4-epoxycyclohexyl methacrylate, etc. may be used singly or in combination of two or more kinds.

The content of the monomer corresponding to the above (ii) is 5 to 40 parts by weight, and specifically 10 to 30 parts by weight with respect to 100 parts by weight of the entire monomers. When the content of the monomer corresponding to the above (i) is less than 5 parts by weight, there is a problem that it is difficult to dissolve in an alkaline aqueous solution, and when it is more than 40 parts by weight, there is a problem that the solubility to the alkaline aqueous solution is excessive. In addition, the content of the monomer corresponding to the above (i) is 60 to 95 parts by weight, and specifically 65 to 90 parts by weight with respect to 100 parts by weight of the entire monomers. When the content of the monomer corresponding to the above (i) is less than 60 parts by weight, there is a problem that the resolution and heat resistance are lowered. When the content of the monomer equivalent to 95 parts by weight is more than 95 parts by weight, the acrylic copolymer is difficult to dissolve in the alkaline aqueous solution as a developer. The problem.

In the RGBW structure, the above-mentioned polyfunctional urethane-based methacrylate unsaturated compound (equivalent to (b)) controls the degree of photocuring and improves the red, green, and blue sub-picture elements and The effect of the height difference of the white sub-picture element is represented by the following chemical formula 1.

Chemical formula 1

In the above Chemical Formula 1, D is a hydrocarbon group having 1 to 20 carbon atoms, specifically an alkylene group, arylene group, or naphthylene group having 6 to 13 carbon atoms, and n and m are each independently an integer of 0 to 2 . In addition, when n + m> 0, the curing degree of the acrylic copolymer can be increased. When both the curing degree and the resolution are considered, when n + m = 2, there is an advantage that both the curing degree and the resolution are optimized.

The weight-average molecular weight of the polyfunctional urethane-based methacrylate compound is 100 to 10,000, and specifically 500 to 8000. If the weight average molecular weight is too small, it may not be combined with the acrylic copolymer, and the efficiency may be poor. If it is too large, it may not be sufficiently combined with the acrylic copolymer, and physical properties such as hardness may be poor.

The polyfunctional urethane-based methacrylate compound (unsaturated compound) can be produced by reacting a commonly used diisocyanate compound with a methacrylate-containing diol compound. The diisocyanate compound is, for example, toluene di Isocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, tetramethylxylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, methylene dicyclohexyl isocyanate, etc. .

The content of the polyfunctional urethane-based methacrylate compound is 10 to 100 parts by weight, and specifically 30 to 60 parts by weight, based on 100 parts by weight of the acrylic copolymer. When the content of the polyfunctional urethane-based methacrylate is less than 10 parts by weight, it is difficult to expect improvement in the level difference of the RGBW structure. When the content is more than 100 parts by weight, there are problems that the resolution and the residual film rate are reduced.

The polyfunctional urethane-based methacrylate compound is a monomer that can be polymerized with the acrylic copolymer by the action of a photoinitiator described later, and contains a double bond and can react with a radical generated by the photoinitiator. Combined with other photopolymerizable monomers or acrylic copolymers to form crosslinked bonds.

Since the above-mentioned multifunctional urethane-based methacrylate has a methacrylate structure instead of an acrylate structure, after bonding with a cross-linked acrylic copolymer, the initial stage of the methacrylate can be adjusted due to the methyl group of the methacrylate. As a result of the light coupling speed, physical properties such as planarization and resolution can be improved. In addition, since a urethane bond is formed in the middle, a stronger bond is formed, and the hardness is better. When a force is applied from the outside, it can have the restoring force to return to the original form, and in particular, it can make the adhesion to the substrate more good.

As the photoinitiator (corresponding to (c)) used in the present invention, a conventional photoinitiator used in a negative photosensitive resin composition can be used, and specifically, an oxime ester compound can be used. The content of the photoinitiator is 0.1 to 30 parts by weight, and specifically 0.5 to 20 parts by weight with respect to 100 parts by weight of the acrylic copolymer. When the content of the photoinitiator is less than 0.1 part by weight, there is a problem that the residual film rate and adhesion force are reduced due to low sensitivity, and when the content is more than 30 parts by weight, there is a problem that solubility and resolution are reduced.

The solvent (equivalent to (d)) used in the present invention achieves the flatness of the interlayer insulating film and prevents the formation of coating streaks to form a uniform pattern profile, and can be used in combination with a negative photosensitive resin that is generally used Examples of conventional solvents include propylene glycol alkyl ether acetates such as propylene glycol monoethyl ether propionate, propylene glycol methyl ether propionate, propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, and propylene glycol butyl ether propionate. Esters; alcohols such as methanol and ethanol; ethers such as tetrahydrofuran; glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; methyl cellosolve acetate, ethyl cellosolve acetate Ethylene glycol alkyl ether acetates; Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether and other diethylene glycols; propylene glycol methyl ether, propylene glycol ether, propylene glycol propyl ether Propylene glycol monoalkyl ethers such as propylene glycol butyl ether; propylene glycol methyl ether acetate, propylene glycol ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate and other propylene glycol alkyl ether acetates; toluene, Aromatic hydrocarbons such as toluene; methyl Ketones such as ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone; or methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, Methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl glycolate, ethyl acetate, butyl glycolate, methyl lactate, ethyl lactate, lactic acid Propyl ester, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate, methyl 2-hydroxy-3-methylbutyrate Ester, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, propyl ethoxyacetate , Butyl ethoxyacetate, methyl propoxyacetate, ethyl propoxyacetate, propyl propoxyacetate, butyl propoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, Butyl Acetate, Butyl Acetate, Methyl 2-methoxypropionate, Ethyl 2-methoxypropionate, Propyl 2-methoxypropionate, 2-methoxypropionate Acid butyl ester, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate Propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, ethyl 2-butoxypropionate, propyl 2-butoxypropionate, Butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, methyl 3-ethoxypropionate, Ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, Propyl 3-propoxypropionate, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, Specific examples of esters such as butyl 3-butoxypropionate include propylene glycol monoethyl ether propionate, propylene glycol methyl ether propionate, which achieves solubility, reactivity with each component, and easily forms a coating film. Propylene glycol alkyl ether propionates such as propylene glycol ethyl ether propionate, propylene glycol propyl ether propionate, and propylene glycol butyl ether propionate may be used alone or as a mixture of two or more kinds as required.

The content of the solvent is 10 to 500 parts by weight, and specifically 30 to 400 parts by weight, based on 100 parts by weight of the acrylic copolymer.

The solid content of the negative photosensitive resin composition of the present invention is 10 to 50% by weight, and specifically 15 to 40% by weight. When the content of the solid content exceeds the above range, the fluidity is too large or too small, and it may not be sufficiently coated on a substrate to be described later.

The negative-type photosensitive resin composition of the present invention may further include a polyfunctional acrylate oligomer and / or a polyfunctional monomer having an ethylenically unsaturated bond, if necessary. The above-mentioned multifunctional acrylate oligomer has 2 to 20 functional groups, and an aliphatic urethane acrylate oligomer, an aromatic urethane acrylate oligomer, an epoxy acrylate oligomer, Epoxy methacrylate oligomer, polyester acrylate oligomer, silicone acrylate oligomer, melamine acrylate oligomer, dendritic acrylate oligomer, etc. They can be used alone or in combination of two or more. Mixed use.

The content of the above-mentioned polyfunctional acrylate oligomer is 1 to 50 parts by weight, and specifically 5 to 30 parts by weight with respect to 100 parts by weight of the acrylic copolymer. When the content of the polyfunctional acrylate oligomer is less than 1 part by weight, there is a problem that the residual film rate is not good due to low sensitivity, and when it is more than 50 parts by weight, there is a problem that the developability is lowered and the resolution is lowered.

In the negative photosensitive resin composition of the present invention, the polyfunctional urethane-based methacrylate unsaturated compound having a different structure (and size) and functioning as a crosslinking agent is introduced simultaneously (equivalent to (b) ) And multifunctional acrylate oligomers, which can be denser with more acrylic copolymers within a specified volume, and can form an insulating film with stronger strength and density.

Specific examples of the polyfunctional monomer having the ethylenically unsaturated bond include dipentaerythritol hexaacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, phthalate diacrylate, and polyethylene. Glycol diacrylate, tetraethylene glycol diacrylate, tricyclodecane dimethanol diacrylate, triglycerol diacrylate, tripropylene ethoxyethyl isocyanurate, trimethylolpropane triacrylate A mixture of one or two or more of the group consisting of derivatives and their methacrylates.

The negative photosensitive resin composition of the present invention may further include conventional additives used in various negative photosensitive resin compositions, such as a silane coupling agent, a surfactant, etc., in order to improve specific physical properties, as necessary. The acrylic copolymer is 100 parts by weight, and the content of the additive may be 0.01 to 5 parts by weight.

In addition, the negative photosensitive resin composition of the present invention is coated on a display device to form an interlayer insulating film. For example, as for the above interlayer insulating film, the negative photosensitive resin composition of the present invention can be applied to a substrate. And performing a heat treatment, a step of curing after development, and forming an interlayer insulating film on the display device. The above heat treatment may be performed at a temperature that is usually performed.

The thickness, various conditions, and the like of the interlayer insulating film are not particularly limited, and can be set to ranges used in ordinary device manufacturing. Therefore, the matters other than the above-mentioned negative photosensitive resin composition can be selected and applied by those skilled in the present invention by appropriately using a known method.

Specifically, the above-mentioned interlayer insulating film can be formed as follows. First, the negative-type photosensitive resin composition of the present invention is coated on the surface of a substrate by a spray method, a roll coating method, a spin coating method, or the like, and the solvent is removed by pre-baking to form a coating film. At this time, the heat treatment may be performed at a temperature of 80 to 130 ° C for 1 to 5 minutes.

Next, according to a previously prepared pattern, visible light, ultraviolet rays, far ultraviolet rays, electron beams, X-rays, and the like are irradiated on the coating film formed as described above, and development is performed with a developing solution to remove unnecessary portions to form a predetermined pattern.

The developing solution is more effective with an alkaline aqueous solution. For example, inorganic hydrazones such as sodium hydroxide, potassium hydroxide, and sodium carbonate; primary amines such as n-propylamine; secondary amines such as diethylamine and n-propylamine; trimethylamine, Tertiary amines such as methyldiethylamine, dimethylethylamine, and triethylamine; alcoholamines such as dimethylethanolamine, methyldiethanolamine, and triethanolamine; or tetramethylammonium hydroxide and tetraethyl hydroxide An aqueous solution of a quaternary ammonium salt such as ammonium. At this time, the developing solution is used after dissolving a basic compound at a concentration of 0.1 to 10% by weight, and a suitable amount of a water-soluble organic solvent such as methanol, ethanol, and a surfactant may be added.

In addition, after developing with the developing solution, washing with ultrapure water for 50 to 180 seconds, removing unnecessary parts, drying, forming a pattern, selectively irradiating ultraviolet rays to the formed pattern, and using a heating device such as an oven The formed pattern is cured at a temperature of 150 to 250 ° C. for 30 to 90 minutes, and finally an interlayer insulating film is obtained.

In addition, the present invention can provide a display device in which the negative photosensitive resin composition of the present invention is coated on a substrate and heat-treated and cured to form an organic insulating film as described above.

The above-mentioned organic insulating film can be used as an organic insulating film for a variety of displays, and particularly can be effectively used for a display for a liquid crystal display device having an RGBW structure.

Hereinafter, the present invention will be described in more detail through examples, but the present invention is not limited to the following examples.

[Example 1] Production of negative photosensitive resin composition

100 parts by weight of an acrylic copolymer solution having a weight average molecular weight (Mw) of 5000, 40 parts by weight of a hexafunctional urethane-based methacrylate (when n and m in Chemical Formula 1 are each 1), as a radical light 10 parts by weight of an oxime ester-based photoinitiator, 3 parts by weight of a silane coupling agent, and 1 part by weight of a surfactant. Propylene glycol monoethyl ether acetate was added so that the solid content of the mixture was 25 parts by weight, and the mixture was filtered through a 0.2 μm microporous filter to produce a negative photosensitive resin composition coating solution.

[Example 2] Production of negative photosensitive resin composition

A photosensitive resin composition coating solution was produced in the same manner as in Example 1 except that the content of the polyfunctional urethane methacrylate was 10 parts by weight instead of 40 parts by weight.

[Example 3] Production of negative photosensitive resin composition

A photosensitive resin composition coating solution was produced in the same manner as in Example 1 except that the content of the polyfunctional urethane-based methacrylate was 100 parts by weight instead of 40 parts by weight.

[Example 4] Production of negative photosensitive resin composition

Except having used 15 weight part of dipentaerythritol hexaacrylates as an ethylenically unsaturated polyfunctional monomer, the photosensitive resin composition coating liquid was manufactured by the method similar to Example 1 mentioned above.

[Example 5] Production of negative photosensitive resin composition

Except having used 30 weight part of dipentaerythritol hexaacrylates as an ethylenically unsaturated polyfunctional monomer, the photosensitive resin composition coating liquid was manufactured by the method similar to Example 1 mentioned above.

[Example 6] Production of negative photosensitive resin composition

A photosensitive resin composition coating liquid was produced in the same manner as in Example 1 except that a ten-functional urethane-based methacrylate was used (when n and m in Chemical Formula 1 were 2). .

[Comparative Example 1] Production of negative photosensitive resin composition

Instead of the polyfunctional urethane methacrylate represented by Chemical Formula 1, 40 parts by weight of dipentaerythritol hexaacrylate, which is an ethylenically unsaturated polyfunctional monomer, was used. In the same manner, a photosensitive resin composition coating liquid was produced.

[Comparative Example 2] Production of negative photosensitive resin composition

Instead of using a polyfunctional urethane-based methacrylate represented by Chemical Formula 1 in an amount of 40 parts by weight of an aliphatic urethane hexaacrylate that is a urethane-based unsaturated polyfunctional monomer, A photosensitive resin composition coating liquid was produced by the same method as in Example 1.

[Comparative Example 3] Production of negative photosensitive resin composition

A photosensitive resin composition coating liquid was produced in the same manner as in Example 1 except that the content of the polyfunctional urethane-based methacrylate represented by Chemical Formula 1 was 110 parts by weight.

Manufacturing of RGBW substrate with organic insulating film formed

a. Manufacturing of RGBW substrate

First, a red color resist was applied to the cleaned glass, and pre-baking was performed on a hot plate having a temperature of 90 ° C for 100 seconds. Next, using a photomask, exposure was performed at an exposure amount of 100 mJ / sq.cm, and development was performed using a 0.04% KOH developer for 60 seconds. In a convection oven having a temperature of 230 ° C., additional execution was performed. Curing for 30 minutes.

According to the method described above, after the green and blue resists are applied, curing is performed. Here, the white pattern is formed by a dark black pattern of a photomask in a red (Red Color) resist exposure process, and the thickness of the cured RGB color is formed to be 2.5 μm.

b. Organic insulating film manufacturing process

On the RGBW substrate manufactured as described above, the negative photosensitive resin composition manufactured in Examples 1 to 6 and Comparative Examples 1 to 3 was applied, and pre-baking was performed in a hot plate having a temperature of 105 ° C for 100 seconds. bell. Next, using a photomask, exposure was performed at an exposure amount of 5 to 70 mJ / sq.cm, and then development was performed using a 2.38% TMAH developer for 100 seconds in a convection oven (Convection Oven) having a temperature of 240 ° C. Curing was additionally performed for 23 minutes to manufacture an RGBW substrate on which an organic insulating film was formed.

[Experimental Example 1] Evaluation of characteristics of negative photosensitive resin composition

The physical properties of the RGBW substrate formed with the organic insulating film, which were produced from the resin compositions of Examples 1 to 6 and Comparative Examples 1 to 3 were evaluated by the following methods. The results are shown in Table 1 below.

(1) Measurement of height difference

With the contact thickness measuring equipment Tencor, the difference in height between the white and RGB color areas was measured (※ Organic film thickness on green color-white) The thickness of the organic film) is represented by ○ if the height difference is 6000 Å or less, △ if it exceeds 6000 and 8000 Å or less, and X if it is more than 8000 and 10,000 Å or less.

(2) Sensitivity

Using the same process as the above-mentioned method for measuring the difference in height, after performing the interlayer insulating film process with different exposure amounts, the time point at which the thickness of the interlayer insulating film is saturated in RGB colors (thickness variation within 500）) is expressed as the best sensitivity. .

(3) Resolution

Through the same process as the above-mentioned method for measuring the height difference, in a white color area, an optical microscope is used to measure the contact hole size of the pattern film formed at the best-sensitivity portion formed. The resolution of the interlayer insulation film is (Open) 6 to 8 µm, which is represented by ○, if it exceeds 8 to 11 µm, it is represented by △, and if it exceeds 11 to 14 µm, it is represented by X.

(4) Residual film rate

The contact thickness measurement equipment Tencor uses the same process as the above-mentioned height difference measurement method to measure the residual film of the interlayer insulating film at the most sensitive part. If the residual film rate is 80% or more, It is represented by ○, if it is less than 80 and more than 75%, it is represented by △, and if it is 75% or less, it is represented by X. Here, the residual film rate means "(thickness after development) / initial thickness) * 100".

Table 1

As shown in Table 1 above, excellent characteristics such as level difference, sensitivity, resolution, and residual film rate of the RGBW substrates formed using the negative-type photosensitive compositions of Examples 1 to 6 of the present invention were confirmed, especially the comparative examples were used. The resolution of the RGBW substrate formed from the negative photosensitive composition of 1 to 3 is very poor. Therefore, when the negative-type photosensitive composition of the present invention is used, it is excellent in level difference, sensitivity, resolution, and residual film rate. In particular, the degree of photocuring can be controlled by using a polyfunctional urethane methacrylate. From this, it was confirmed that it is a negative photosensitive resin composition which can achieve high flatness and high resolution.

[Experimental Example 2] Evaluation of mechanical characteristics of negative photosensitive resin composition

Regarding the RGBW substrate with the organic insulating film formed from the resin compositions of Examples 1 to 6 described above, the nanoindenter equipment and the Berkovich Tip were used to mechanically inspect the organic insulating film. The characteristics were evaluated, and the analysis results are shown in Table 2 below.

Table 2

As shown in Table 2 above, the strength of the organic insulating film formed using the negative-type photosensitive composition of Examples 1 to 6 of the present invention is about 0.29 Gpa or more. In particular, Example 4 and DPHA which conventionally also include DPHA In terms of 5, it was confirmed that the hardness was relatively improved.

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Claims (9)

A negative photosensitive resin composition comprising: an acrylic copolymer; a polyfunctional urethane methacrylate compound represented by the following Chemical Formula 1; a radical photoinitiator; and a solvent; a chemical formula 1 In Chemical Formula 1, D is a hydrocarbon group having 1 to 20 carbon atoms, and n and m are each independently an integer of 0 to 2. The negative-type photosensitive resin composition according to item 1 of the scope of application, wherein the polyfunctional urethane-based methacrylate unsaturated compound and the radical The content of the photoinitiator and the solvent is 1 to 100 parts by weight, 0.1 to 30 parts by weight, and 10 to 500 parts by weight, respectively. The negative photosensitive resin composition according to item 1 of the scope of the patent application, wherein D is an alkylene group, an arylene group, or a naphthylene group having 6 to 13 carbon atoms. The negative photosensitive resin composition according to item 1 of the scope of application, wherein the weight-average molecular weight of the polyfunctional urethane-based methacrylate compound is 100 to 10,000. The negative-type photosensitive resin composition according to item 1 of the scope of patent application, wherein the solid content is 10 to 50% by weight. The negative-type photosensitive resin composition according to item 1 of the patent application scope, further comprising a polyfunctional acrylate oligomer and / or a polyfunctional monomer having an ethylenically unsaturated bond. The negative photosensitive resin composition according to item 1 of the scope of patent application, further comprising an additive in the group consisting of a silane coupling agent, a surfactant, and a mixture thereof, with respect to the acrylic copolymer 100 The content of the additive is 0.01 to 5 parts by weight. The negative-type photosensitive resin composition according to item 1 of the scope of patent application, wherein n and m of the chemical formula 1 satisfy n + m> 0. The negative-type photosensitive resin composition according to item 1 of the scope of patent application, wherein n and m of the chemical formula 1 satisfy n + m = 2.