KR100377859B1 - New copolymers and surface-sensitive resin compositions using them to control surface properties - Google Patents

Abstract

The present invention relates to an acrylic copolymer resin represented by the following general formula (I), copolymerized with an acrylic monomer containing benzyl methacrylate, methacrylic acid, and fluorine, with a number average molecular weight of 10,000 to 50,000.

<Formula I>

here

R ₁ , R ₂ and R ₃ are each independently a hydrogen atom or a methyl group; R ₄ is an alkyl group or aromatic compound having 1 to 8 carbon atoms containing fluorine, and m, n, and l are integers, and the ratio of m / n / l is 60 to 70/34 to 15/1 to 15 on a molar ratio basis.

Description

New copolymer for controlling surface properties and photosensitive resin composition using same

The present invention relates to a novel copolymer for controlling surface properties and a photosensitive resin composition using the same. The invention also relates to compositions for color filters of liquid crystal displays or image scanners, compositions for dispersing phosphors in plasma displays, etching resists for printed circuit boards, solder resists used for soldering printed circuit boards, and compositions for printing plates. It is about manufacture.

In the case of a color filter in a conventional photosensitive resin composition, Korean Patent Publication 95-7419 discloses a composition comprising a copolymer of methacrylate / benzyl methacrylate (molar ratio 20/80, number average molecular weight 15,00-18,000) as a copolymer. US Patent 5,368,976 claims a composition characterized by benzyl methacrylate / methacrylate / styrene (65/25/10 wt%, number average molecular weight 40,000). U. S. Patent No. 5,514, 502 discloses compositions with the addition of copolymers in the form of styrene / acrylate / benzylacrylamide, but these compositions do not fully overcome surface properties such as uniformity, improved adhesion, ease of development and residue problems.

In the case of the photosensitive resin composition in which the phosphor of the plasma display is dispersed, the coating of the phosphor by the phosphor and the water-soluble polymer composition was performed in Korean Patent Application Publication No. 95-6429.

Etching resists and solder resists used in printed circuit boards are mainly studied for improving resolution and adhesion. In the case of Korea Patent Publication No. 91-8709, a solder composition using a resin obtained by reacting a novolak-type epoxy resin with unsaturated carboxylic acid or unsaturated anhydride is proposed. In the case of Korean Patent Publication No. 94-5618, a photosensitive resin composition for circuit recording was proposed by using a copolymer made of acrylic acid / methacrylic acid / methyl methacrylate / methylacrylate / 2-phenoxy ethyl acrylate. Was not completely removed.

In order to improve the properties of the photosensitive resin composition, the present inventors were able to synthesize a copolymer having a completely new structure from the conventional structure by including fluorine in the molecule, and using the substrate (glass, printing). Poor adhesion to the circuit board), the problem of selective dissolution of the exposed and unexposed areas during development for pattern formation, the problem of residues reattached to the substrate once dissolved, and also excellent surface uniformity during coating The photosensitive resin composition was invented. When the copolymer of the present invention and the composition thereof are used for the production of color filters of liquid crystal displays, excellent properties were exhibited.

Color filters for liquid crystal displays are stacked on the top of the liquid crystal device to reproduce the color signal, the manufacturing method for this includes a dyeing method, pigment dispersion method, printing method, electrodeposition method and the like. Printing methods include direct printing by offset printing (Toppon printing), Ink-jet printing (Canon) and screen printing (screening printing). They are working fast, but have low decomposition capability, and are currently in development for commercialization. Electrodeposition [ Proc, Intern , Microprocess Conference, 430, (1991)] is a kind of plating method by electrical interaction, which is not yet commercialized. As the most common manufacturing method, dyeing and pigment dispersion are mainly used.

Dyeing method (Japanese Patent Laid-Open No. 62-269928, 63-253302, 63-314501) is a method of manufacturing by dyeing a natural resin such as gelatin, casein or a low melting resin such as polyvinyl alcohol. Due to the lack of optical stability and thermal stability, it has been difficult to be applied for high-quality liquid crystal displays. Pigment dispersion methods introduced in US Pat. Nos. 5,368,976, 5,514,502, etc., which increase the stability to heat or light pointed out above and which have a simple manufacturing process, have been developed and widely used. The pigment dispersion method is a method of uniformly dispersing an organic pigment in a highly transparent photosensitive resin to produce a photosensitive color resist, and coating and exposing the glass substrate of a liquid crystal display to form a predetermined desired pattern. That is, an important technique of the pigment dispersion method may be efficient pigment dispersion, and if the pigment is not dispersed properly, the quality of the final display may be significantly degraded.

Problems in the manufacturing process by the pigment dispersion method may cause a residue problem of dirtying other color pixels during development, which impairs the purity of the color and makes it impossible to reproduce a vivid color. It may also be difficult to control the process by dissolving too quickly or too late for the alkaline solution used during development. This problem is due to the structure of the copolymer or due to the properties of the composition. If the surface of the final product is uneven, there is a problem that the color filter is less transparent. In order to solve this problem, it is determined that the structure of the copolymer is inevitable, and the present inventors have prepared a new copolymer containing fluorine and developed various photosensitive resin compositions using the same.

The present invention relates to an acrylic copolymer resin represented by the following general formula (I), and copolymerizes an acrylic monomer containing benzyl methacrylate, methacrylic acid, and fluorine.

<Formula I>

Wherein R ₁ , R ₂ and R ₃ are each independently a hydrogen atom or a methyl group; R ₄ is an alkyl group having 1 to 8 carbon atoms or an aromatic group containing fluorine, m, n, and l are integers, and the ratio of m / n / l is 60 to 70/34 to 15 / l to 15 on a molar ratio basis. .

The number average molecular weight of the copolymer resin was designed to synthesize from 10,000 to 50,000. The molecular weight was confirmed by gel permeation chromatography. Table 1 shows a representative example of the copolymer.

TABLE 1

BzMA: benzyl methacrylate

MAA: acrylic acid

FEMA: trifluoroethyl acrylate

HFIM: Hexafluoroisopropyl methacrylate

In most cases, the copolymer of general formula (I) is used alone, but in some cases, 5 to 95% by weight of the copolymer of general formula (II) is mixed with respect to the general formula (I), or Even if it mixes 5-95 weight% of copolymers of the following general formula (III) with respect to (I), the outstanding photosensitive resin composition can be obtained.

<Formula II>

<Formula III>

Wherein R ₁ , R ₂ and R ₃ are each independently a hydrogen atom or a methyl group; m, n, l are integers, and the ratio of m and n in the general formula (II) is 70:30 (molar ratio), the number average molecular weight is 10,000 to 50,000, and m and n in the general formula (III). , the ratio of l is 70:15:15 (molar ratio), and a number average molecular weight is 10,000-50,000.

The photosensitive resin composition using the copolymer of this invention is as follows.

The acrylic copolymer resin of the general formula (I) alone or in combination with the general formula (II) or the general formula (III), 1 to 40 parts by weight, 1 to 30 parts by weight of the multifunctional acrylic monomer, aceto as a photopolymerization initiator 0.1 to 15 parts by weight of a phenone derivative or an S-triazine compound was used, 1 to 20 parts by weight of a pigment in the case of a color filter and a solder resist composition, 1 to 20% by weight of a phosphor in a plasma display, and an organic solvent. After addition, the mixture was stirred to prepare a photosensitive resin composition.

The mixing ratio of the photosensitive resin composition may be different according to each use, but the copolymer and the constituent compound which are the core are not different. However, when the pigment is added, it may be added differently depending on the use of the product.

Hereinafter, the components of the photosensitive resin composition according to the present invention will be described in more detail.

In the preparation of the photosensitive resin composition, 1 to 40% by weight, preferably 1 to 20% by weight of the novel fluorine-containing acrylic copolymer of the general formula (I) is added. Surface uniformity in the molecular compound is bonded to the copolymer (containing fluorine in itself) to further enhance the uniformity of the film, and has excellent uniformity with a thickness difference of only 150 to 300 Å at the center and the end of the film. Provide a film. In the developing process, it showed good developing characteristics to be applied to the production process, and showed no characteristic of contamination on adjacent pixels after the developing process. In addition, the roughness of the top of the film after the development process showed an excellent surface like the uniformity described above. The difference was about 150-300 mm 3. According to the purpose, even when mixing the general formula (I) and the general formula (II) or (III), the advantages of the uniformity of the coating, the development process, the elimination of residue problems, etc. It became.

The multifunctional acrylic monomer is a crosslinking agent, and radicals are generated by ultraviolet (UV) exposure, and the radicals polymerize the multifunctional monomer to form a crosslinkable polymer. The multifunctional acrylic monomer used as the photopolymerization crosslinking agent of the present invention includes trimethylol propanetriacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate and the like. The multifunctional acrylic monomer may add 5 to 20 parts by weight based on 100 parts by weight of the total composition, preferably 5 to 10 parts by weight.

As a photoinitiator, an acetophenone derivative and S-triazine type are used individually or in mixture. For acetophenone derivatives, 1-hydroxycyclohexylphenyl ketone (Irgacure 184, manufactured by Ciba), 2,2-dimethoxy-2-phenylacetophenone (Irgacure 651, manufactured by Ciba), 3-benzyl-2-dimethyl Amino-1- (4-morpholinylnophenyl-butan-1one (Irgacure 369, from Ciba), 2-methyl-1- (4- (methylthio) phenyl) -2- (4-morpholinyl)- 1-propanone (Irgacure 907, manufactured by Ciba), 2-hydroxy-2-methyl-1-phenylpropan-1-one (Irgacure 1173, manufactured by Ciba) can be used. Butoxystyryl-5-trichloromethyl-1,3,4-oxadiazole was used alone or in combination and used in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the total composition. Preferably it is added at 0.1 to 7% by weight.

In the case of color filters or solder resists, pigments are used. In the case of the solder resist, a general purpose pigment may be used as long as it does not adversely affect the dispersion, but in the color filter composition, a pigment of finely processed fine particles must be used. It is preferable that the pigment particle size is mainly 0.3 micrometer or less, and it is suitable that 90% or more becomes fine particle which shows the distribution of 0.1 micrometer. When the size of the pigment is larger than this, a problem of pigment dispersion occurs in preparing the composition, and thus, the light transmittance is not smooth and thus the permeability of the color filter is poor. The pigment can be used both an organic pigment and an inorganic pigment. Pigments shown here are indicated by the numbers in the Color Index published by The Society of Dyers and Colourist.

Representative pigments used for the production of color filters are as follows.

Although the addition amount of a pigment is 1-20 weight part with respect to 100 weight part of whole compositions, Preferably 1-15 weight part is added. If the amount of pigment in the color filter is not appropriate, a poor quality product is obtained.

Phosphors are used to reproduce colors in plasma displays. The amount adds 1 to 10 parts by weight, preferably 1 to 5 parts by weight based on 100 parts by weight of the composition.

As the organic solvent, a solvent capable of spin coating on glass is used. Alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol and i-propyl alcohol, and cellosolves include methyl cellosolve and ethyl cellosolve. Carbitols include diethylene glycol methyl ether and diethylene glycol ethyl ether. As esters, ethyl acetate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate ethyl lactate, acetone, methyl isobutyl ketone, cyclohexanone, cellosolve acetate in the ketone system is methyl cellosolve acetate , Diethylglycol methyl acetate, diethylglycol ethyl acetate, propylene glycol methyl ether acetate, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol diethyl ether (diglyme), tetrahydro Furan, amide system are N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, lactones are t-butyrolactone, aromatic system is benzene, toluene, xylene, saturated hydrocarbons As the n-heptane, n-hexane, n-octane is used. The amount added is added to be 20 to 80% by weight of the total composition.

After mixing the fluorine-containing novel copolymer, the multifunctional acrylic monomer, the photopolymerization initiator, the pigment, the fluorescent substance, and the organic solvent described above, and coating the substrate with a thickness of 1 to 2 μm by spin coating, 365 nm (I-line) UV light should be exposed at an intensity of 20 to 60 mJ / cm 2 to observe development characteristics in an aqueous alkali solution (pH 11-12). After heating for 5 minutes at 200 ° C to 250 ° C, the presence of residue was observed under a microscope (100 to 500 times), and the uniformity of the surface was measured by measuring the height with Alpa Step 500.

Hereinafter, the synthesis examples of the novel copolymers of the present invention and the experimental examples of the photosensitive resin composition using the same will be described in detail by examples.

New Copolymer Synthesis

F1 synthesis)

To 150 ml of propylene glycol methyl ether acetate, 22.05 parts (0.125 mol) of benzyl methacrylate was added 4.62 parts (0.054 mol) of methacrylic acid, 3.33 parts (0.02 mol) of trifluoroethyl acrylate, and flowed for 1 hour with nitrogen. It heated up to 90 degreeC.

0.15 parts of AIBN (0.9 mmol, 0.5% by weight relative to the total amount of monomers) was added, and then maintained at 100 ° C. for 5 hours. After completion of the reaction, the precipitate was precipitated in ether. The precipitate precipitate was dissolved in tetrahydrofuran and again ether / hexane. The precipitate was dried at filtration, dried and filtered, and the yield of the obtained F1 copolymer was 98%, and gel permeation chromatography (GPC) confirmed Mn 24,700, Mw 41,700 and the dispersion degree of 1.69.

F2 synthesis)

The amount of AIBN was added in the same manner as in the above example of F1 synthesis except that 0.1 part (0.35 wt% based on the total amount of monomers) was added. The yield of the obtained F2 copolymer was 99%, and gel permeation chromatography (GPC) confirmed Mn 29,400, Mw 49,900 and the dispersion degree of 1.69.

F3 synthesis)

The amount of AIBN was added in the same manner as in the above example of F1 synthesis, except that 0.3 part (1.0 wt% of the total amount of monomers) was added. The yield of the obtained F3 copolymer was 97%, Mn 20,000, Mw 32,000, dispersion degree was 1.60 by gel permeation chromatography (GPC).

F4 synthesis)

The amount of AIBN was carried out in the same manner as in the above example of F1 synthesis, except that 0.07 parts (0.25% by weight relative to the total monomer) and 0.02 mole of hexafluoroisopropyl methacrylate were added. The yield of the obtained F4 copolymer was 99%, and gel permeation chromatography (GPC) confirmed Mn 34,000, Mw 56,000, and dispersion degree of 1.62.

F5 synthesis)

To 150 ml of propylene glycol methyl ether acetate was added 23.44 parts (0.133 mol) of benzyl methacrylate, 4.71 parts (0.057 mol) of methacrylic acid, and 1.68 parts (0.01 mol) of trifluoroethyl acrylate. The temperature was raised to 90 ° C. 0.15 part (0.9 mmol, 0.5 weight% with respect to monomer total amount) of AIBN was added, and then 100 degreeC was maintained for 5 hours. After the reaction was completed, it was precipitated in ether. The precipitate precipitate was dissolved in tetrahydrofuran, precipitated again with ether / nucleic acid, filtered and dried. The yield of the obtained F5 copolymer was 96%, and gel permeation chromatography (GPC) confirmed Mn 23,800, Mw 40,700 and the dispersion degree of 1.68.

F6 synthesis)

The amount of AIBN was added in the same manner as in the example of F5 synthesis, except that 0.1 part (0.35 wt% based on the total amount of monomers) was added. The yield of the obtained F6 copolymer was 96%, and gel permeation chromatography (GPC) confirmed Mn 28,000, Mw 47,600 and the dispersion degree of 1.70.

F7 synthesis)

The amount of AIBN was carried out in the same manner as in the example of F5 synthesis, except that 0.3 part (1.0 wt% based on the total monomer) and 0.01 mol of hexafluoroisopropyl methacrylate were added. The yield of the obtained F8 copolymer was 99%, Mn 20,500, Mw 33,000 dispersion degree was 1.61 by gel permeation chromatography (GPC).

F8 synthesis)

The amount of AIBN was carried out in the same manner as in the example of F5 synthesis, except that 0.75 parts (0.25% by weight relative to the total amount of monomers) were added. The yield of the obtained F8 copolymer was 99% and Mn 34,500, Mw 56,600 dispersion degree was 1.64 by gel permeation chromatography (GPC).

Examples of the photosensitive resin composition applied using the copolymer containing fluorine described above will be described in detail below.

Color filter composition

Example 1

After stirring the above composition to the optimum dispersion, it was passed through a filter of 5 ㎛ size. After spin-coating to 1-2 mm on the glass plate, it heated at 90 degreeC for 2 minutes, and exposed. The exposed light source was adjusted according to the experiment with a size of 20 to 60 mJ / cm 2 using 365 nm (I-line) light.

The developing condition using alkaline developing solution (pH = 11-12) was observed in seconds, and the surface uniformity was evaluated by comparing the height of the center and the tip.

The effect of the residue was to stack the remaining green and blue colors, and to check whether there was any contamination continuously.

Examples 2-7

The same method as in Example 1 was carried out except that copolymers F3, F4, F5, F6, F7, and F8 of Table 1 were used, respectively.

Example 8

C.I. Pigment Green 36 and C.I. The same procedure as in Example 1 was carried out except that Pigment Yellow 83 was mixed and used in a ratio of 85:15.

Example 9

C.I. The same method as in Example 1 was conducted except that Pigment Blue 15: 1 was used.

Example 10

The same method as in Example 1 was carried out except that the F1 copolymer of Table 1 and the copolymer of Formula (II) were mixed at a weight% of 50:50.

Example 11

The same method as in Example 1 was carried out except that the F1 copolymer of Table 1 and the copolymer of Formula (II) were mixed at a weight ratio of 9:95.

Example 12

The same method as in Example 1 was performed except that the F1 copolymer of Table 1 and the copolymer of the general formula (III) were mixed at a weight% of 50:50.

Example 13

The same method as in Example 1 was carried out except that the F1 copolymer of Table 1 and the copolymer of the general formula (III) were mixed at a weight ratio of 9:95.

Example 14

The same method as in Example 1 was carried out except that the organic solvent was used by mixing 50% by weight of PGMEA and ethyl ethoxy propionate at 50:50.

Printed circuit composition

(Solder resist, circuit forming resist)

Example 15

Example 16

The same method as in Example 15 was carried out except that 10 parts of Irgacure 369 was used.

Table 2 shows the measured physical properties.

The thickness was measured by Alpa Step 500 and the uniformity showed the difference between the center and the tip of the sample. The developing time was visually shown in 10 second units, and 30 to 40 seconds was represented by 1, 40 to 50 seconds was represented by 2, and 50 seconds or more were represented by 3. The residue or dispersion state was confirmed by an electron microscope.

TABLE 2

In order to improve the properties of the photosensitive resin composition, the present invention is a copolymer having a structure completely new from the conventional structure by incorporating fluorine in the molecule, and using the same as a copolymer (glass, printed circuit board) that has appeared in the existing photosensitive resin composition. The problem of poor adhesion is poor, the problem of selective dissolution of exposed and unexposed parts during development for pattern formation, and the problem of residues that are once re-adhered to the substrate, the surface uniformity is also excellent.

Claims (5)

Acrylic copolymer represented by the following general formula (I): <Formula I> In the above general formula, each of R ₁ , R ₂ and R ₃ is independently a hydrogen atom or a methyl group; R ₄ is an alkyl group having 1 to 8 carbon atoms or an aromatic group containing fluorine; m, n, l are integers, and the ratio of m / n / l is 60 to 70/34 to 15/1 to 15 on a molar ratio basis. The number average molecular weight of the copolymer resin is 10,000 to 50,000. A photosensitive composition comprising a copolymer of the following general formula (I) and a copolymer of the following general formula (II) in a weight ratio of 5:95 to 95: 5: <Formula I> [In the general formula, R ₁ , R ₂ , R ₃ , R ₄ , m, n, l and molecular weight are the same as in claim 1] <Formula II> In the general formula, R ₁ and R ₂ are each independently a hydrogen atom or a methyl group; m and n are integers, the ratio is 70:30 on a molar ratio basis, and the number average molecular weight is 10,000 to 50,000. A photosensitive composition comprising a copolymer of the following general formula (I) and a copolymer of the following general formula (III) in a weight ratio of 5:95 to 95: 5: <Formula I> [In the general formula, R ₁ , R ₂ , R ₃ , R ₄ , m, n, l and molecular weight are the same as in claim 1] <Formula III> In the above general formula, each of R ₁ , R ₂ and R ₃ is independently a hydrogen atom or a methyl group; The molar ratio of m, n, l is 70:15:15, and a number average molecular weight is 10,000-50,000. The photosensitive composition according to claim 3, comprising a copolymer of general formula (I), general formula (II) and general formula (III). In the photosensitive resin composition, a) a novel acrylic copolymer containing fluorine represented by the following general formula (I);