KR101043397B1 - Stripping composition for removing color resist of tft-lcd manufacturing process - Google Patents

Abstract

The present invention relates to a stripping liquid composition for removing color resist of a TFT LCD process, and more particularly, to a stripping solution for removing a color resist pattern in order to reuse a defective substrate generated during a color filter process of a TFT LCD. It relates to a composition.

The stripper composition of the present invention is difficult to remove the color resist pattern to reuse the color filter substrate which was mostly discarded, so that the production yield can be greatly improved and economical.

 Color resist, stripping solution

Description

Stripping liquid composition for removal of color resist of TFC manufacturing process {STRIPPING COMPOSITION FOR REMOVING COLOR RESIST OF TFT-LCD MANUFACTURING PROCESS}

1 is a scanning electron microscope (Hitachi Corporation, model name; S-4100) photographs comparing the color resist removal performance of the color resist stripper composition of Example 5 and Comparative Example 1 at 60 ° C.

The present invention relates to a stripper composition for removing a color resist for TFT-LCD, and more particularly, a black mask or a black mask by removing only a color resist of a defective substrate generated during a color filter process. The present invention relates to a stripper composition for removing a color resist for TFT LCD to reuse a glass substrate.

The color filter substrate is composed of a color filter red, green, and blue pattern, a black matrix that serves to block leakage light between each pixel and improve contrast, and a common electrode that applies a voltage to the liquid crystal cell. The process of making a color filter is as follows.                         

Depending on the application, Cr / CrOx or an organic material, which is used as a black matrix material, is coated on the glass substrate to form a pattern. After forming a black mask pattern, a color resist pattern for color realization is formed by a photolithography technique. The color resist is applied onto a glass substrate and exposed to light to cure the color resist by photopolymerization. After the exposure is completed, the color resist is removed by the development to remove the unexposed areas and undergoes a calcination process.

The color resist is produced by a pigment dispersion method, a dyeing method, an electrodeposition method, etc. Among these, a pigment dispersion method is mainly used. In general, an organic pigment that implements color is dispersed in a color resist such as a photopolymerization initiator, a monomer, a binder, and the like that are photosensitive compositions. The photoinitiator is a highly sensitive compound that receives light to generate radicals, and the monomer is bonded to a polymer after initiation of the polymerization reaction by radicals, thereby insoluble in the developing solvent. The binder protects the liquid monomer from the developer at room temperature, and stabilizes the dispersion of the pigment and determines the reliability of heat resistance, light resistance, chemical resistance, and the like of the red, green, and blue patterns.

Bad color filter generated in the current color filter process Once the color resist of the substrate is cured, it is almost impossible to repair by removing only the wrong part of the pattern, and since there is little solvent that can remove the color resist, the bad color filter is Most of them are disposed of immediately without rework.

The color resist has negative characteristics, and in general, the negative resist is more difficult to peel off than the positive type. For this reason, the negative type resist required strong peeling performance, and for this reason, conventionally, reactive ion etching (RIE) using an inorganic stripping solution and plasma was used. In the case of the inorganic stripping solution, when sulfuric acid, nitric acid, fuming sulfuric acid, a mixture of nitric acid and hydrogen peroxide are heated to a high temperature of 120 ° C. or higher, it not only adversely affects the safety of workers but also increases the risk of fire caused by heating. There is discomfort that requires careful attention. As a specific example of the inorganic stripping solution, a mixture of alkylbenzene sulfonic acid and a non-halogenated aromatic hydrocarbon solvent having a boiling point of 150 ° C. or higher is disclosed in Japanese Patent Laid-Open No. 51-72503, and alkylarylsulfonic acid, aqueous aromatic sulfonic acid, and non-halogenated solution. A mixture of aromatic hydrocarbon solvents is disclosed in US Pat. No. 4,165,294, and strippers in which polar or nonpolar organic solvents are added to eutectic acid and 1,2-dihydroxybenzene are disclosed in European Patent Publication No. 0119337, respectively.

In the case of a method using reactive ion etching (RIE) using plasma, the etching of the cured color resist which cannot be removed by general wet etching is a method of continuously removing by using O ₂ -RIE and SF ₆ -RIE. 5,756,239, a cured color resist using polyester, polyamide, and noblock resin as an absorbent layer and a mixture of polysilane, polysiloxane, organosilicon compound, silica, and silicon nitride as the barrier layer. As a barrier layer using a plasma, a method using RIE using sulfur hexafluoride or nitrogen trifluoride is disclosed in US Pat. No. 5,059,500, respectively. However, the etching of the color filter using plasma requires high vacuum and high energy, it is difficult to set the process conditions, and it is difficult to use in a large area and has the disadvantages such as the high cost of equipment.

As can be seen in the above example of the prior art, it is difficult to remove a large amount of color resist stably in the conventional color resist removal method, there is a problem that the safety of workers, productivity or yield is low.

Therefore, the present invention is to solve the problems in the prior art as described above, it is difficult to remove the color resist pattern, the color filter manufacturing of the TFT LCD can improve the production yield by reusing the defective color filter substrate that was mostly discarded An object of the present invention is to provide a peeling liquid composition for removing a color resist used during the process.

In order to achieve the above object, the present invention

(a) 1 to 10% by weight of inorganic alkali hydroxide or alkyl ammonium hydroxide,

(b) 40-95 wt% of dimethyl sulfoxide, and

(c) 4 to 50% by weight of water provides a stripper composition for color filter reuse.

Preferably, the composition of the present invention is at least one compound selected from the group consisting of (d) water-soluble amine compounds, N-alkyl-2-pyrrolidone, dialkylene glycol ethers, inorganic alkali acetates, and alkanol amines It may be further included in 0.05 to 111 parts by weight based on 100 parts by weight of the total peeling liquid composition.

Hereinafter, the present invention will be described in detail.

The present invention relates to a stripper composition for removing a color resist pattern in order to reuse a defective substrate generated during the color filter process of TF LCD.

The stripper composition for reuse of the color filter substrate of the present invention comprises a) an inorganic alkali hydroxide or an alkyl ammonium hydroxide. In the case of the color filter process, inorganic alkali hydroxides can be used since they are not significantly affected by residual metals. Since the alkyl ammonium hydroxide is not stable, it is preferable to use a dissolved state in water.

The content of the inorganic alkali hydroxide or alkyl ammonium hydroxide component is preferably 1 to 10% by weight based on the total composition. When the content of the inorganic alkali hydroxide or alkyl ammonium hydroxide is less than 1% by weight, it is difficult to completely remove the colorresist due to poor penetration into the polymer component constituting the colorresist, and when it exceeds 10% by weight, swelling phenomenon. It is severe and the solubility of the color resist in the polymer component is reduced.

The inorganic alkali hydroxide is preferably used by selecting one or more from the group consisting of sodium hydroxide and potassium hydroxide. The alkyl ammonium hydroxide is at least one selected from the group consisting of tetraethyl ammonium hydroxide, tetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide, trimethylbenzyl ammonium hydroxide, and ammonium hydroxide It is preferable to use.

In addition, the stripper composition for removing the color resist of the present invention includes b) dimethyl sulfoxide. The dimethyl sulfoxide penetrates into the polymer constituting the color resist and serves to separate the color resist from the glass substrate. The content of dimethyl sulfoxide in the stripper composition of the present invention is preferably 40 to 95% by weight based on the total composition. If the content of the dimethyl sulfoxide is less than 40% by weight, there is a problem in that the penetration into the color resist is weak and cannot be completely removed. If the content of the dimethyl sulfoxide is more than 95% by weight, the viscosity and freezing point of the color resist stripper composition are increased to increase convenience. There is a problem of deterioration.

In the stripper composition for removing the color resist of the present invention, c) water is an essential ingredient, preferably using pure water filtered through an ion exchange resin, and using ultrapure water having a specific resistance of 18 megaohms or more. More preferably.

The water content is preferably 4 to 50% by weight based on the total composition. If the water content is less than 4% by weight, the alkylammonium hydroxide is not activated, so the penetration into the color resist is weakened.If the water content is more than 50% by weight, the composition change due to the evaporation of water at the process temperature is severe. There is a problem that a decrease in (Life Time) appears.

In addition, the stripper composition for removing the color resist of the present invention is selected from the group consisting of d) a water-soluble amine compound, N-alkyl-2-pyrrolidone, dialkylene glycol ether, inorganic alkali acetate, and alkanol amine. The compound may be further selected from 0.05 to 111 parts by weight based on 100 parts by weight of the total stripping liquid composition.

The said water-soluble amine compound can be used in order to improve the performance of a peeling liquid composition. It is preferable to use a water-soluble hydroxyl amine compound as said water-soluble amine compound. The hydroxyl amine exerts a function of effectively penetrating the hydroxide ions generated by reacting with the hydrogen ions of water into the contact surface between the color resist and the substrate, and dissolves the polymer and dissolves the binder of the polymer and the pigment. . It is preferable to use the hydroxyl amine in the state of 50% aqueous solution. The use amount of the water-soluble amine compound is preferably 2 to 20 parts by weight based on 100 parts by weight of the total stripper composition. If the content of the water-soluble amine compound is less than 2 parts by weight, it is difficult to completely remove the color resist, and if it exceeds 20 parts by weight, there is a problem in that the corrosiveness to the underlying film becomes large.

In the color resist stripper composition according to the present invention, the N-alkyl-2-pyrrolidone may be used to improve performance, and N-alkyl-2-pyrrolidone has a function of dissolving and swelling a polymer. have. The content of the N-alkyl-2-pyrrolidone is preferably 2 to 20 parts by weight based on 100 parts by weight of the total stripper composition. When the content of the N-alkyl-2-pyrrolidone is less than 2 parts by weight, the dissolving power for the polymer, which is a component of the color resist, is reduced. There is a problem of weakening.                     

The N-alkyl-2-pyrrolidone is preferably used by selecting one or more from the group consisting of N-ethyl-2-pyrrolidone and N-methyl-2-pyrrolidone.

The color resist stripper composition according to the present invention may use a dialkylene glycol ether to improve the performance, the dialkylene glycol ether is characterized by peeling the color resist from the glass substrate, penetrates into the polymer and polymer and pigment particles It serves to dissolve the binder. The content of the dialkylene glycol ether is preferably 2 to 50 parts by weight based on 100 parts by weight of the total stripper composition. When the content of the dialkylene glycol ether is less than 2 parts by weight, the dissolving ability of the color resist is lowered. When the content of the dialkylene glycol ether is more than 50 parts by weight, the content of dimethyl sulfoxide is reduced, and the penetration force is weakened.

The dialkylene glycol ether is diethylene glycol ethyl ether, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol diacetate, diethylene glycol monobutyl ether acetate, diethylene glycol It is preferred to use one or more selected from the group consisting of monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monoethyl ether.

In addition, in the color resist stripper composition according to the present invention, an inorganic alkali acetate may be used to improve performance, and the inorganic alkali acetate penetrates into a polymer or a dye to form an alkyl ammonium hydroxide and an alkylaryl ammonium hydroxide. There is a function to improve the function. The content of the inorganic alkali acetate is preferably 0.05 to 1 parts by weight based on 100 parts by weight of the total stripper composition. If the inorganic alkali acetate content is less than 0.05 parts by weight can not be expected to improve the ability to penetrate into the polymer of the color resist constituent component, if the content exceeds 1 parts by weight of the inorganic alkali acetate to the weight part of water in the present composition is precipitated There is a problem that causes.

The inorganic alkali acetate is preferably used one or more selected from the group consisting of potassium acetate, and sodium acetate.

In the color resist stripper composition according to the present invention, an alkanol amine may be used to improve performance, and the alkanol amine has excellent solubility in photosensitive compounds to facilitate penetration of alkyl ammonium hydroxide between polymers. It also helps to dissolve the binder of polymer and pigment. The content of the alkanol amine is preferably 2 to 20 parts by weight based on 100 parts by weight of the total stripper composition. If the content of the alkanol amine is less than 2 parts by weight, the function of dissolving the photosensitive compound and the binder is poor, and thus the functional improvement cannot be expected. There is a problem going crazy.

The alkanol amine may be selected from one or more selected from the group consisting of monoethanol amine, diethanol amine, triethanol amine, methyl ethanol amine, ethyl ethanol amine, dimethyl ethanol amine, diethyl ethanol amine, and amino ethoxy ethanol. desirable.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited to the following Examples. On the other hand, in the following examples, unless otherwise stated, percentages and mixing ratios are based on weight.

[Example]

In Examples and Comparative Examples of the present invention, performance evaluation of the color resist stripper composition was carried out by the following method of removing color resist using a color filter substrate of A company.

(1) color resist removal test

Specimen Manufacturing

Color filter patterns were made on LCD corning glass with Cr / CrOx deposited on the bottom, and color resist was applied using the following photo process in the order of red, green, and blue. A universally used color resist composition (trade name: DCR-725S available from Dongjin Semichem Co., Ltd.) was spin coated to apply a final film thickness of 1.7 mu m. Subsequently, the resist film was pre-baked at 90 ° C. for 120 seconds on a hot plate. Subsequently, after exposure and development for 60 seconds at 21 degreeC with the 2.38% tetramethylammonium hydroxide (TMAH) developer, the patterned specimen was hard-baked at 220 degreeC for 20 minutes.

Color resist removal test

The specimens were immersed in a stripper composition for removing color resist at a temperature of 60 ° C. for 5 minutes, 10 minutes, and 15 minutes, respectively. Subsequently, the specimen was removed from the color resist stripper composition, washed with ultrapure water and dried with nitrogen gas, and then examined by scanning electron microscope (SEM) to determine whether a color resist remained in the pattern. Evaluation based on the same criteria as shown in Table 2 below.

◎: When all the red cyan patterns are completely removed.

○: When only the cyan pattern is removed.

(Triangle | delta): When only a blue pattern is removed.

X: When not all red cyan patterns are removed

(2) metal film corrosion test

Metal film corrosion test

The specimens were immersed in a stripper composition for removing color resist at a temperature of 60 ° C. for 30 minutes each. Subsequently, the specimen was removed from the color resist stripper composition, washed with ultrapure water, dried with nitrogen gas, and examined with a scanning electron microscope to determine whether the metal undercut phenomenon occurred in the pattern. And the results are shown in Table 3 below.

○: When there is no undercut phenomenon in the lower metal film

△: when there is some undercut phenomenon in the lower metal film

X: When undercut phenomenon appears severely in lower metal film

Examples 1-7 and Comparative Examples 1-2

The contents of the components (a) to (d) according to the present invention were mixed at the ratios shown in Table 1 below to prepare the color resist stripper compositions of Examples 1 to 7 and Comparative Examples 1 to 2, respectively. Thus, the color-resist stripping liquid composition thus obtained was subjected to the (1) color resist removal test and (2) metal film corrosiveness test described above, and the results are shown in Tables 2 and 3 below.

Composition of Color Resist Stripping Liquid Composition (a)
Tetramethylammonium hydroxide
(weight%) (b)
Dimethyl sulfoxide
(weight%) (c)
water
(weight%) (d) (parts by weight) Water soluble hydroxyl amine N-alkyl-2-pyrrolidone Dialkylene glycol ether Potassium acetate n-methylethanolamine Carbitol PGME
Example One One 95 4 - - - - - - 2 4 80 16 - - - - - - 3 4 80 16 One 2 - 3 - - 4 6 70 24 One 2 - 3 - - 5 6 60 34 2 2 - - 0.1 10 6 6 50 44 2 2 - - 0.3 10 7 6 70 24 One - 3 0.3 - Comparative example One
16 20 64 - - - - - 2 0.2 99 0.8 - - - - -

week)

HDA: Hydroxylamine

NMP: N-methyl-2-pyrrolidone

PGME: 1-methoxy-2-propanol

Carbitol: Diethylene Glycol Monoethyl Ether                     

Color resist removal performance of color resist stripper composition Immersion time 5 minutes 10 minutes 15 minutes room
city
Yes One ○ ◎ ◎ 2 ○ ◎ ◎ 3 ○ ◎ ◎ 4 ○ ◎ ◎ 5 ○ ◎ ◎ 6 ○ ◎ ◎ 7 ○ ◎ ◎ 8 ○ ◎ ◎ ratio
School
Yes One × × △ 2 × × △

Metal wiring corrosion test Immersion time 30 minutes Example One ◎ 2 ◎ 3 ◎ 4 ◎ 5 ◎ 6 ◎ 7 ◎ 8 ◎ Comparative example One ○ 2 ○

As can be seen from the results of Tables 2 and 3, the peeling liquid composition of Examples 1 to 7 of the present invention has a metal wiring corrosion resistance or higher than that of the conventional compared to Comparative Examples 1 to 2, in particular, the color resist removal performance is very high. It can be seen that excellent.

Figure 1 shows a scanning electron microscope (Hidachi, model name; S-4100) photograph comparing the color resist removal performance of the color resist stripper composition of Example 5 and Comparative Example 1. 1 shows the results obtained by testing the temperature of the color resist stripper composition at 60 ° C.

1, the color resist was removed clearly compared with the comparative example 1 when using the peeling liquid composition of Example 5 of this invention.

As described above, the color resist stripper composition according to the present invention can easily remove the color resist within a short time. In addition, it is possible to minimize the corrosion of the lower metal wiring during the color resist removal process, there is an advantage that can be rinsed with water only in the subsequent rinsing process without the use of organic solvents such as isopropyl alcohol, dimethyl sulfoxide.

Claims (9)

(a) 1 to 10% by weight of inorganic alkali hydroxide or alkyl ammonium hydroxide, (b) 40-95 wt% of dimethyl sulfoxide, and (c) As a component (d) with respect to 100 weight part of color resist stripper composition containing 4-50 weight% of water (i) 2 to 20 parts by weight of a water-soluble amine compound, 2 to 20 parts by weight of N-alkyl-2-pyrrolidone and 2 to 50 parts by weight of dialkylene glycol ether, (ii) 2 to 20 parts by weight of a water-soluble amine compound, 2 to 20 parts by weight of N-alkyl-2-pyrrolidone, 0.05 to 1 parts by weight of inorganic alkali acetate, and 2 to 20 parts by weight of alkanol amine, or (iii) 2 to 20 parts by weight of a water-soluble amine compound, 2 to 50 parts by weight of a dialkylene glycol ether, and 0.05 to 1 part by weight of an inorganic alkali acetate. The method of claim 1, The inorganic alkali hydroxide is selected from the group consisting of sodium hydroxide, and potassium hydroxide color resist stripper composition for color filter reuse. The method of claim 1, The alkyl ammonium hydroxide is at least one selected from the group consisting of tetraethyl ammonium hydroxide, tetramethyl ammonium hydroxide, tetrabutyl ammonium hydroxide and trimethylbenzyl ammonium hydroxide. Color resist stripper composition for the treatment. delete The method of claim 1, The water-soluble amine compound is a color resist stripper composition for color filter reuse, characterized in that the hydroxyl amine. The method of claim 1, The N-alkyl-2-pyrrolidone is at least one member selected from the group consisting of N-ethyl-2-pyrrolidone, and N-methyl-2-pyrrolidone. Resist stripper composition. The method of claim 1, The dialkylene glycol ether is diethylene glycol ethyl ether, diethylene glycol dimethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol A color resist stripper composition for color filter reuse, characterized in that at least one selected from the group consisting of monobutyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monoethyl ether. The method of claim 1, The inorganic alkali acetate is a color resist stripper composition for color filter reuse, characterized in that at least one selected from the group consisting of potassium acetate, and sodium acetate. The method of claim 1, The alkanol amine is characterized in that at least one selected from the group consisting of monoethanol amine, diethanol amine, triethanol amine, methyl ethanol amine, ethyl ethanol amine, dimethyl ethanol amine, diethyl ethanol amine, and amino ethoxy ethanol Color resist stripper composition for color filter reuse.

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