KR20230071884A - A thermosetting overcoat resin composition and an overcoat formed therefrom, and a substrate comprising the overcoat layer - Google Patents

Abstract

The present invention relates to a thermosetting overcoat resin composition, an overcoat formed thereby, and a substrate including the same and, more specifically, to a thermosetting overcoat resin composition which comprises a copolymer, as a binder resin, of a specific structure, including an epoxy group-containing monomer, a monocarboxylic acid group-containing monomer, and a maleic acid monomer as a polymerization unit to provide an overcoat with excellent mechanical properties such as flatness, adhesion, hardness, and the like, heat resistance, and chemical resistance, and at the same time, provide excellent storage stability and enabling high-speed coating to increase processing properties, thereby shortening process time and increasing productivity, an overcoat formed thereby, and a substrate including the same. The thermosetting overcoat resin composition comprises a binder resin, a multifunctional monomer, and organic solvents.

Description

A thermosetting overcoat resin composition and an overcoat formed therefrom, and a substrate comprising the overcoat layer

The present invention relates to a thermosetting overcoat resin composition, an overcoat formed therefrom, and a substrate comprising the overcoat layer, and more particularly, to a specific polymeric unit containing an epoxy group-containing monomer, a monocarboxylic acid group-containing monomer, and a maleic acid monomer. By including the copolymer of the structure as a binder resin, an overcoat excellent in mechanical properties such as flatness, adhesion, hardness, heat resistance and chemical resistance is provided, and at the same time, storage stability is excellent and high-speed coating is possible, thereby improving processability. It relates to a thermosetting overcoat resin composition capable of reducing process time and improving productivity by improving process time, an overcoat formed therefrom, and a substrate including the overcoat layer.

Recently, the TFT-LCD industry has been bifurcated with OLED displays, and is fiercely competing in the market for TV displays, small and medium-sized displays for notebooks and computer monitors, and mobile displays of 10 inches or less.

For this reason, the TFT-LCD industry is striving to achieve high resolution, high brightness, low power, and large size through various structural changes to differentiate from OLED displays. requesting materials.

The thermosetting overcoat resin composition is used as a flattening film and a protective film of TFT-LCD, and plays a role in flattening the level difference between RGB pixels on the upper plate, and also prevents organic solvents, acids, and alkali solutions used during the manufacturing process. Accompanying the function of protecting the pixel.

Therefore, the overcoat used for the LCD top plate is also increasing the required physical property limit, in particular, high flatness that can be mixed with RGB and WRGB pixel structures, resistance to various wet chemicals such as organic solvents, acids, and alkalis. Chemical properties are mainly required. In addition, it is necessary to improve processability and productivity in order to lower the price, so improvement in processability such as high-speed coating is required.

Accordingly, various thermosetting overcoat resin compositions have been proposed (Related prior art documents: Korean Registered Patent Nos. 10-0848196 and 10-1336305), but they provide an overcoat with excellent flatness, chemical resistance, adhesiveness, mechanical properties, etc. A thermosetting overcoat resin composition capable of coating and improving processability has not yet been developed.

An object of the present invention is to provide an overcoat excellent in mechanical properties such as flatness, adhesion, hardness, heat resistance, chemical resistance, and storage stability, and at the same time, to improve processability by enabling high-speed coating and excellent storage stability. A thermosetting overcoat resin composition that is particularly suitable for use in forming an overcoat on various electronic parts including TFT-LCD panels using RGB pixels or WRGB pixels as it can shorten process time and improve productivity, an overcoat formed therefrom, and the overcoat It is to provide a substrate (particularly, a color filter substrate for TFT-LCD) including a layer.

The present invention to solve the above technical problem, (A) a binder resin which is a copolymer containing an epoxy group-containing monomer, a monocarboxylic acid group-containing monomer and a maleic acid monomer as polymerized units; (B) a multifunctional monomer; and (C) an organic solvent.

According to another aspect of the present invention, an overcoat formed by curing the thermosetting overcoat resin composition of the present invention is provided.

According to another aspect of the present invention, a substrate including an overcoat layer formed from the thermosetting overcoat resin composition of the present invention is provided.

The overcoat formed from the thermosetting overcoat resin composition of the present invention has excellent mechanical properties such as flatness, adhesiveness, hardness, heat resistance, chemical resistance, and storage stability, and can be used as a flattening or protective film for various electronic parts. It can be suitably used for TFT-LCD panels using RGB pixels or WRGB pixels. In addition, the thermosetting overcoat resin composition of the present invention enables high-speed coating and improves processability, thereby reducing process time and improving productivity.

1 is a schematic diagram of a structure of one specific example of a color filter substrate (RGB (Red, Green, Blue) substrate) including an overcoat layer formed from a thermosetting overcoat resin composition of the present invention on its surface.

In this specification, the term “(meth)acryl” includes acryl, methacryl, or a combination thereof, and the term “(meth)acrylate” includes acrylate, methacrylate, or a combination thereof.

Hereinafter, the present invention will be described in detail.

The thermosetting overcoat resin composition of the present invention includes (A) a binder resin; (B) a multifunctional monomer; and (C) an organic solvent.

(A) binder resin

The binder resin included in the thermosetting overcoat resin composition of the present invention is a copolymer containing an epoxy group-containing monomer, a monocarboxylic acid group-containing monomer, and a maleic acid monomer as polymerized units.

In one embodiment, the epoxy group-containing monomer is glycidyl group, 3,4-epoxybutyl group, 2,3-epoxycyclohexyl group, 3,4-epoxycyclohexyl group, 2-glycidyloxy-1-propyl group, 3-methyloxetane-3-methyl group, 3-ethyloxetane-3-methyl group, 6,7-epoxyheptyl group, or a combination thereof, and more specifically, glycidyl of the following structure It may be methacrylate.

In one embodiment, in the copolymer that is the binder resin, the epoxy group-containing monomer is 1 part by weight or more, 5 parts by weight or more, 10 parts by weight or more, 15 parts by weight or more based on 100 parts by weight of the total monomers for forming the copolymer. or more, 20 parts by weight or more, 25 parts by weight or more, or 30 parts by weight or more, and also in an amount of 70 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, 55 parts by weight or less, or 50 parts by weight or less. can be included

In one embodiment, the monocarboxylic acid group-containing monomer may be acrylic acid, methacrylic acid, or a combination thereof, and more specifically, may be acrylic acid having the following structure.

In one embodiment, the copolymer as the binder resin contains 1 part by weight or more, 2 parts by weight or more, 5 parts by weight or more of the monocarboxylic acid group-containing monomer based on 100 parts by weight of the total monomers for forming the copolymer, 7 parts by weight or more, 10 parts by weight or more, 12 parts by weight or more, or 15 parts by weight or more, and also 60 parts by weight or less, 55 parts by weight or less, 50 parts by weight or less, 45 parts by weight or less, or 40 parts by weight or less. can be included in the amount of

In one embodiment, the maleic acid monomer may be maleic acid, maleic anhydride, or a combination thereof, and more specifically, maleic anhydride having the following structure.

In one embodiment, the copolymer as the binder resin contains 1 part by weight or more, 2 parts by weight or more, 3 parts by weight or more, or 4 parts by weight or more of the maleic acid monomer based on 100 parts by weight of the total monomers for forming the copolymer. Or it may be included in an amount of 5 parts by weight or more, and may also be included in an amount of 30 parts by weight or less, 25 parts by weight or less, 20 parts by weight or less, 15 parts by weight or less, or 10 parts by weight or less.

In one embodiment, the copolymer that is the binder resin may further include a carboxylate-containing monomer as a polymerization unit. The carboxylate may be an alkyl carboxyl group, an aryl carboxyl group, or a combination thereof, and the content thereof is, for example, 1 part by weight or more, 2 parts by weight or more, based on 100 parts by weight of the total monomers for forming the binder resin copolymer. 5 parts by weight or more, 7 parts by weight or more, or 10 parts by weight or more, and may also be 50 parts by weight or less, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, 25 parts by weight or less, or 20 parts by weight or less. It may be less than or equal to, but is not limited thereto.

In one embodiment, the carboxylate containing monomer is methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth)acrylate, caprolactone-modified (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, or a combination thereof, and more specifically, methyl (meth)acrylate ) acrylate.

In one embodiment, the copolymer that is the binder resin may further include an alkyl group or an aryl group-containing monomer as a polymerization unit. The alkyl group or aryl group may be an alkyl group having 1 to 4 carbon atoms, a phenyl group, a substituted phenyl group, or a combination thereof, and the content thereof is, for example, based on 100 parts by weight of the total monomers for forming the binder resin copolymer, 1 It may be 5 parts by weight or more, 2 parts by weight or more, 3 parts by weight or more, 4 parts by weight or more, or 5 parts by weight or more, and also 50 parts by weight or less, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less. It may be less than or 25 parts by weight or less, but is not limited thereto.

In one embodiment, the alkyl group or aryl group-containing monomer may be styrene, 4-methoxy styrene, 4-methyl styrene, 1,3-butadiene and isoprene, or a combination thereof, and more specifically may be styrene. .

In one embodiment, the binder resin may be a copolymer represented by Formula 1 below:

[Formula 1]

In Formula 1,

R is hydrogen or an alkyl group or an aryl group,

R ₁ and R ₂ are each independently hydrogen or a methyl group;

w, x and y are molar ratios of the corresponding polymerized units, respectively, and are each independently within the range of 0.01 to 0.98.

More specifically, the binder resin may be a copolymer represented by Formula 1-1 below:

[Formula 1-1]

In Formula 1-1,

R, R ₁ , R ₂ , w, x and y are as defined in Formula 1 above,

R ₃ and R ₄ are each independently hydrogen or a methyl group;

이며, 여기서 R₇은 알킬기 또는 아릴기이고,R ₅ is

, wherein R ₇ is an alkyl group or an aryl group,

R ₆ is an alkyl group having 1 to 4 carbon atoms, a phenyl group, or a substituted phenyl group;

z and t are molar ratios of the corresponding polymerized units, respectively, and are each independently in the range of 0 to 0.5.

Each of the alkyl group and the aryl group (including the phenyl group) may be unsubstituted or substituted with a hydroxy group, an alkyl group, or an alkoxy group (eg, an alkyl group or alkoxy group having 1 to 6 or 1 to 4 carbon atoms).

In one embodiment, except when otherwise defined, the number of carbon atoms in the alkyl group may be 1 to 20, 1 to 16, 1 to 10, 1 to 6, or 1 to 4; The number of carbon atoms in the aryl group may be 6 to 14, 6 to 10 or 6. More specifically, examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, t-butyl, hexyl, cyclohexyl, 2-ethylhexyl, dicyclopentanyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, 2-hydroxyethyl or ethoxymethyl, and examples of the aryl group include phenyl, benzyl, 4-methylphenyl, 4-methoxyphenyl, 4-hydroxyphenyl, or 3-hydroxyphenyl, but are limited thereto. It doesn't work.

In one embodiment, w may be 0.01 or more, 0.05 or more, 0.1 or more, 0.15 or more, or 0.2 or more, and may be 0.98 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, or 0.4 or less.

In one embodiment, the x may be 0.01 or more, 0.05 or more, 0.1 or more, 0.15 or more, or 0.2 or more, and may also be 0.98 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, or 0.4 or less.

In one embodiment, the y may be 0.01 or more, 0.02 or more, 0.05 or more, 0.1 or more, 0.15 or more, or 0.2 or more, and also 0.98 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, or 0.5 or less.

In one embodiment, the z may be 0.01 or more, 0.05 or more, or 0.1 or more, and may also be 0.5 or less, 0.45 or less, or 0.4 or less.

In one embodiment, the t may be 0.01 or more, 0.05 or more, or 0.1 or more, and may also be 0.5 or less, 0.45 or less, or 0.4 or less.

There is no particular limitation on the synthesis of the copolymer used as the binder resin in the present invention, and known materials and methods may be used.

As the solvent used in the synthesis of the copolymer, alcohols such as methanol and ethanol; ethers such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol methylethyl ether; propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, and propylene glycol alkyl ether acetates such as propylene glycol butyl ether acetate may be used alone or in combination of two or more selected, but are not limited thereto. .

The polymerization initiator used in the synthesis of the copolymer is generally a radical polymerization initiator such as 2,2' azobis isobutyronitrile, 2,2' azobis- (2,4-dimethylvaleronitrile), azo compounds such as 2,2'azobis-(4-methoxy-2,4-dimethylvaleronitrile); organic peroxides such as benzoyl peroxide, t-butyl peroxy fivalate, and 1,1' bis-(t-butyl peroxy) cyclohexane; and hydrogen peroxide, but are not limited thereto.

In one embodiment, the copolymer used as the binder resin may have a weight average molecular weight of 1,000 to 50,000 and a degree of dispersion of 1.0 to 10.0, and more specifically, a weight average molecular weight of 10,000 to 25,000 and a degree of dispersion. It may be 1.5 to 3.0, but is not limited thereto.

In addition, the copolymer used as the binder resin may be a random copolymer that is not constrained by the arrangement order of each polymerization unit, but is not limited thereto.

The copolymer used as the binder resin in the present invention can form an overcoat film excellent in flatness, transmittance, hardness, chemical resistance, heat resistance, and adhesion when thermally cured at a curing temperature of, for example, 180 to 250 ° C. The thermosetting overcoat resin composition of the present invention can be coated on a substrate at an increased coating rate. Therefore, by shortening the overcoat process time, the TFT-LCD manufacturing process time can be shortened and productivity can be improved.

The content of the binder resin in the thermosetting overcoat resin composition of the present invention may be appropriately adjusted as needed. In one embodiment, for example, based on 100 parts by weight of the total composition, the binder resin may be included in an amount of 1 part by weight or more, 5 parts by weight or more, 10 parts by weight or more, 20 parts by weight or more, or 30 parts by weight or more , In addition, it may be included in an amount of 80 parts by weight or less, 75 parts by weight or less, 70 parts by weight or less, 65 parts by weight or less, or 60 parts by weight or less, but is not limited thereto.

(B) multifunctional monomer

As the polyfunctional monomer included in the thermosetting overcoat resin composition of the present invention, a bifunctional or trifunctional or higher functional (meth)acrylate can be used.

Examples of the bifunctional (meth)acrylate include ethylene glycol (meth)acrylate, 1,6-hexanediol (meth)acrylate, 1,9-nonanediol (meth)acrylate, and propylene glycol (meth)acrylate. rate, tetraethylene glycol (meth)acrylate, bisphenoxy ethyl alcohol fluorene diacrylate, and the like.

Examples of the trifunctional or higher functional (meth)acrylate include trishydroxyethyl isocyanurate tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol. Litol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc. are mentioned.

One selected from these bifunctional or trifunctional (meth)acrylates alone or in combination of two or more may be used as the multifunctional monomer.

The content of the polyfunctional monomer in the thermosetting overcoat resin composition of the present invention can be appropriately adjusted as needed. In one embodiment, for example, based on 100 parts by weight of the total composition, the polyfunctional monomer may be included in an amount of 1 part by weight or more, 2 parts by weight or more, 3 parts by weight or more, or 5 parts by weight or more, and also, 40 It may be included in an amount of less than 35 parts by weight, less than 30 parts by weight, less than 25 parts by weight or less than 20 parts by weight, but is not limited thereto.

(C) organic solvent

As the organic solvent included in the thermosetting overcoat resin composition of the present invention, an appropriate organic solvent may be used in consideration of compatibility with the binder resin, the multifunctional monomer, and other additives described later, for example, methanol and ethanol. alcohols such as; ethers such as dichloroethyl ether, n-butyl ether, diisoamyl ether, methylphenyl ether, and tetrahydrofuran; glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether; Cellosolve acetates, such as methyl cellosolve acetate, ethyl cellosolve acetate, and diethyl cellosolve acetate; carbitols such as methyl ethyl carbitol, diethyl carbitol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, and diethylene glycol diethyl ether; propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate and propylene glycol propyl ether acetate; Aromatic hydrocarbons, such as toluene and xylene; Ketones such as methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl-n-propyl ketone, methyl-n-butyl ketone, methyl-n-amyl ketone, and 2-heptanone ; saturated aliphatic monocarboxylic acid alkyl esters such as ethyl acetate, n-butyl acetate and isobutyl acetate; lactic acid esters such as methyl lactate and ethyl lactate; oxyacetic acid alkyl esters such as methyl oxyacetate, ethyl oxyacetate, and butyl oxyacetate; Alkoxy acetic acid alkyl esters, such as methoxy methyl acetate, methoxy ethyl acetate, methoxy butyl acetate, ethoxy methyl acetate, and ethoxy ethyl acetate; 3-oxy propionic acid alkyl esters such as 3-oxy methyl propionate and 3-oxy ethyl propionate; 3-alkoxy propionic acid alkyl esters such as 3-methoxy methyl propionate, 3-methoxy ethyl propionate, 3-ethoxy ethyl propionate, and 3-ethoxy methyl propionate; 2-oxypropionic acid alkyl esters such as methyl 2-oxypropionate, ethyl 2-oxypropionate, and propyl 2-oxypropionate; 2-alkoxy propionic acid alkyl esters such as 2-methoxy methyl propionate, 2-methoxy ethyl propionate, 2-ethoxy ethyl propionate, and 2-ethoxy methyl propionate; 2-oxy-2-methylpropionic acid esters such as 2-oxy-2-methyl methyl propionate, 2-oxy-2-methyl ethyl propionate, 2-methoxy-2-methyl methyl propionate, 2-ethoxy-2- monooxy monocarboxylic acid alkyl esters of 2-alkoxy-2-methyl alkyl propionate such as methyl ethyl propionate; esters such as 2-hydroxy ethyl propionate, 2-hydroxy-2-methyl ethyl propionate, hydroxy ethyl acetate, and 2-hydroxy-3-methyl methyl butanoate; and ketonic acid esters such as ethyl pyruvate, N-methylformamide, N,N-dimethylformamide, N-methylformanilide, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzylethyl ether, dihexyl ether, acetylacetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate , Diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, phenyl cellosolve acetate, and the like may be used alone or in combination of two or more solvents.

The content of the organic solvent in the thermosetting overcoat resin composition of the present invention can be appropriately adjusted as needed. In one embodiment, for example, based on 100 parts by weight of the total composition, the organic solvent may be included in an amount of 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, or 30 parts by weight or more, and also 98 parts by weight It may be included in an amount of less than 97.99 parts by weight, less than 90 parts by weight, less than 80 parts by weight, less than 70 parts by weight or less than 60 parts by weight, but is not limited thereto.

(D) any other additives

In addition to the components (A) to (C) described above, the thermosetting overcoat resin composition of the present invention may optionally further contain one or more other additives within a range capable of achieving the object of the present invention.

As such other additives, one or more additives commonly included in thermosetting overcoat resin compositions may be used without particular limitation.

For example, a surfactant capable of improving coating properties by adjusting the surface energy of the overcoat may be used as other additives. As such a surfactant, a fluorochemical surfactant or a silicone surfactant can be used, for example. Commercially available fluorinated surfactants include BM-1000, BM-1100 (BM Chemie Co.), Proride FC-135/FC-170C/FC-430 (Sumitomo 3M Co., Ltd.), SH-28PA/-190/SZ-6032 (Tore Silicon Co., Ltd.) and the like may be used. Commercially available silicone surfactants include BYK's BYK-310, BYK-313, BYK-320, BYK-333, etc., and BYK-307 may be preferably used in terms of dispersibility, but is not limited thereto. .

When the thermosetting overcoat resin composition of the present invention includes such a surfactant, the content thereof may be, for example, in the range of 0.01 to 10 parts by weight based on 100 parts by weight of the total composition, but is not limited thereto.

In one embodiment, the total solid content of the thermosetting overcoat resin composition of the present invention may be 10 to 40% by weight. If the solids content is too low than the above level, a sufficient coating thickness may not be obtained, and conversely, if the solid content is too high, the storage stability of the composition may be deteriorated.

When the thermosetting overcoat resin composition of the present invention is used for flattening and preparing a protective film to prevent steps or deterioration of RGB pixels generated during the TFT-LCD manufacturing process, mechanical properties such as flatness, adhesiveness, hardness, heat resistance, resistance A planarization film or a protective film having excellent chemical properties and storage stability is provided, and at the same time, storage stability is excellent, and processability is improved by enabling high-speed coating, thereby reducing process time and improving productivity.

Therefore, according to another aspect of the present invention, an overcoat formed by curing the thermosetting overcoat resin composition of the present invention; and an overcoat layer formed from the thermosetting overcoat resin composition of the present invention.

After coating the thermosetting overcoat resin composition of the present invention on a substrate, removing the solvent to uniformly form a coating film of the overcoat resin composition, heat treatment is performed to obtain a flattening film and a protective film for TFT-LCD.

As the substrate, for example, glass, quartz, silicon or the like can be used.

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

Removal of the solvent is preferably performed by heat treatment and reduced pressure through a vacuum device. These conditions of reduced pressure and heat treatment vary depending on the type and ratio of the organic solvent component used in the composition, but, for example, it is preferable to heat-treat under reduced pressure in a state of 0.5 to 2.0 torr and heat treatment at 80 to 120 ° C. for about 80 to 200 seconds.

The process of curing the thermosetting resin composition uses thermal crosslinking through high-temperature heat treatment, and, for example, it is treated at a temperature of 180 to 250 ° C for 15 to 120 minutes to finally form a flattening film and a protective film for TFT-LCD.

The thickness of the protective film (ie, overcoat layer) formed as described above is preferably 0.1 to 6 μm, and when there are irregularities on the substrate on which the protective film for optical devices is formed, the value is understood as the value at the top of the irregularities. It should be.

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. However, the scope of the present invention is not limited thereto.

[Example]

Preparation Example: Preparation of Copolymer

In a 500 mL polymerization vessel equipped with a reflux condenser and a stirrer, 2,2'azobis-2,4-dimethylvaleronitrile (V- 65) 5 parts by weight and 200 parts by weight of diethylene glycol methylethyl ether as a solvent were added. Subsequently, the monomers according to the components and compositions shown in Table 1 were added, and the copolymer was polymerized by stirring at a polymerization temperature of 70° C. for 7 hours under a nitrogen atmosphere. The solid content of the monomer was added at 30% by weight.

[Table 1]

Examples 1 to 6 and Comparative Examples 1 to 5: Preparation of thermosetting overcoat resin composition

The thermosetting overcoat resin compositions of Examples 1 to 6 and Comparative Examples 1 to 5 were prepared using each copolymer obtained in the above Preparation Example as a binder resin.

Based on 100 parts by weight of the binder resin, 20 parts by weight of a multifunctional monomer (dipentaerythritol hexa(meth)acrylate) and 0.01 part by weight of other additives (DIC F-554) were mixed according to the components and compositions shown in Table 2 below, , dissolved in propylene glycol methyl ether acetate (PGMEA) and diethylene glycol methyl ethyl ether (MEDG) at a ratio of 6:4 to have a solid content concentration of 20% by weight to prepare a thermosetting overcoat resin composition solution. The balance described in Table 2 below means that the solvent is added in an amount excluding the content of the binder resin, the content of the polyfunctional monomer, and the content of other additives, based on 100% by weight of the total composition. That is, it means that the solvent is added at 44.99% by weight excluding 45% by weight of the binder resin, 10% by weight of the polyfunctional monomer, and 0.01% by weight of other additives.

[Table 2]

Using a slit coater on a glass substrate, each of the above-prepared thermosetting overcoat resin composition solutions was applied to a film thickness of 2.0 μm, and the coating speed was measured. Each thermosetting overcoat resin composition solution prepared above is coated on a glass substrate or color filter substrate using a spin coater to have a film thickness of 2.0 μm and baked in a convection oven at 230° C. for 30 minutes to form an overcoat film on the glass substrate. did

For the compositions and overcoat films prepared in each Example and Comparative Example, the following evaluation was performed, and the results are shown in Table 3 below.

(1) Coating speed

After visually checking the level at which uncoating does not occur while applying the thermosetting overcoat resin to the glass substrate using a slit coater, the total amount of coating is fixed under the condition that uncoating does not occur, and the discharge time and discharge amount are adjusted to perform the following math. The coating rate was evaluated using Equation 1.

[Equation 1]

Coating speed (mm/s) = coating distance (mm) / coating time (s)

(2) Flatness

The profile of the RGB substrate where the color resist (Red, Green, Blue) is repeatedly located in the black matrix that divides the pixels is measured with an alpha stepper, and the largest value among the pixel steps is called D1. When the profile was measured and the largest value of the central step of the subpixel was set as D2, the flatness was obtained using Equation 2 below.

[Equation 2]

(3) adhesion

After the overcoat film prepared on the glass substrate was left at high temperature (121° C.), high pressure (2 atm), and high humidity (100% humidity) for 24 hours, adhesion was evaluated using a checkered tape method. The checkerboard tape method uses a cutter knife to cut 11 lines of cuts at intervals of 1 mm on the overcoat film to the depth of the top surface of the glass substrate, and then vertically cuts 11 lines of cuts at intervals of 1 mm to the depth of the top surface of the glass substrate to create 100 checkerboards. It is an adhesion test in which an adhesive tape (3M, 310-M) is pasted on the checkerboard pattern and then removed after forming the pattern. As a result of the test, the number of peeled checkerboard patterns was measured and the adhesiveness of the cured film was evaluated according to the following criteria.

○: The number of peeled checkerboard patterns is 5 or less

△: 6 to 49 number of peeled checkerboard patterns

Χ: the number of stripped checkerboard patterns is 50 or more

(4) surface hardness

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

(5) heat resistance

The prepared overcoat film was heated in a clean oven at 250° C. for 60 minutes and the change in thickness was measured. From each thickness change, heat resistance was evaluated according to the following criteria.

○: thickness change less than 3%

△: thickness change of 3% or more to less than 5%

Χ: thickness change of 5% or more

(6) Chemical resistance

After immersing the overcoat film prepared on the glass substrate in an N-methylpyrrolidone solution at 50° C. for 10 minutes, chemical resistance was evaluated by observing changes in the appearance of the overcoat film.

(7) storage stability

After the thermosetting overcoat resin composition was left in a low-temperature storage at 5° C. for 6 months, if the change in viscosity was within 5% of the initial viscosity, it was judged as “excellent”, and if the change in viscosity was 5% or more, it was judged as “poor”.

[Table 3]

As shown in Table 3, when an overcoat film is formed as a planarization film or a protective film on a substrate, when the thermosetting overcoat resin composition of the present invention is used, coating speed, flatness, surface hardness, chemical resistance, and storage stability are compared. It can be seen that it is superior to the example.

Therefore, the thermosetting overcoat resin composition of the present invention has excellent storage stability, and when a planarization film or a protective film is formed on a substrate using the same, processability can be improved through high-speed coating, and color filter bends can be effectively flattened. And, it can be seen that it is possible to provide a planarization film and a protective film in which adhesion, mechanical properties, heat resistance and chemical resistance are excellently maintained without deterioration in the post process.

Claims (14)

(A) a binder resin which is a copolymer containing an epoxy group-containing monomer, a monocarboxylic acid group-containing monomer, and a maleic acid monomer as polymerized units;
(B) a multifunctional monomer; and
(C) an organic solvent;
A thermosetting overcoat resin composition. The method of claim 1, wherein the epoxy group-containing monomer is glycidyl group, 3,4-epoxybutyl group, 2,3-epoxycyclohexyl group, 3,4-epoxycyclohexyl group, 2-glycidyloxy-1-propyl group A thermosetting overcoat resin composition having a 3-methyloxetane-3-methyl group, a 3-ethyloxetane-3-methyl group, a 6,7-epoxyheptyl group, or a combination thereof. The thermosetting type overcoat resin composition according to claim 1, wherein the copolymer, which is the binder resin, contains an epoxy group-containing monomer in an amount of 1 part by weight to 70 parts by weight based on 100 parts by weight of the total monomers for forming the copolymer. The thermosetting overcoat resin composition according to claim 1, wherein the monocarboxylic acid group-containing monomer is acrylic acid, methacrylic acid, or a combination thereof. The thermosetting overcoat resin according to claim 1, wherein the copolymer, which is the binder resin, contains a monocarboxylic acid group-containing monomer in an amount of 1 part by weight to 60 parts by weight based on 100 parts by weight of the total monomers for forming the copolymer. composition. The thermosetting overcoat resin composition according to claim 1, wherein the maleic acid monomer is maleic acid, maleic anhydride, or a combination thereof. The thermosetting type overcoat resin composition according to claim 1, wherein the copolymer, which is the binder resin, contains maleic acid monomer in an amount of 1 part by weight to 30 parts by weight based on 100 parts by weight of the total monomers for forming the copolymer. The thermosetting overcoat resin composition according to claim 1, wherein the copolymer as a binder resin further contains a carboxylate-containing monomer as a polymerization unit. The thermosetting type overcoat resin composition according to claim 1, wherein the copolymer as a binder resin further contains an alkyl group or an aryl group-containing monomer as a polymerization unit. The thermosetting overcoat resin composition according to claim 1, wherein the binder resin is a copolymer represented by Formula 1 below:
[Formula 1]

In Formula 1,
R is hydrogen or an alkyl group or an aryl group,
R ₁ and R ₂ are each independently hydrogen or a methyl group;
w, x and y are molar ratios of the corresponding polymerized units, respectively, and are each independently within the range of 0.01 to 0.98. The thermosetting overcoat resin composition according to claim 10, wherein the binder resin is a copolymer represented by Formula 1-1:
[Formula 1-1]

In Formula 1-1,
R, R ₁ , R ₂ , w, x and y are as defined in claim 8;
R ₃ and R ₄ are each independently hydrogen or a methyl group;
R ₅ is

, wherein R ₇ is an alkyl group or an aryl group,
R ₆ is an alkyl group having 1 to 4 carbon atoms, a phenyl group, or a substituted phenyl group;
z and t are molar ratios of the corresponding polymerized units, respectively, and are each independently in the range of 0 to 0.5. The thermosetting overcoat resin composition according to claim 1, wherein the multifunctional monomer is a bifunctional or trifunctional or higher functional (meth)acrylate. An overcoat formed by curing the thermosetting overcoat resin composition according to any one of claims 1 to 12. A substrate comprising an overcoat layer formed from the thermosetting overcoat resin composition according to any one of claims 1 to 12.

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