TWI442192B - A color resist remover composition for tft-lcd preparation - Google Patents

Description

Color photoresist stripping solution composition for thin film transistor liquid crystal display

The present invention relates to a color photoresist stripping solution composition for a thin film transistor liquid crystal display (TFT-LCD), and more particularly to a color photoresist for a defective substrate which occurs in a color filter process and a color photoresist containing color resist The overcoat layer has excellent removal effect, and can re-use color photoresist removed from a black mask or a glass substrate, and can recover colored light for a thin film transistor liquid crystal display using a color filter substrate The resist strips the solution composition.

In general, the substrate of the color filter is a black matrix that blocks the red, green, and blue patterns of the color filter and light leakage between the pixels, and serves to improve contrast, a coating used as a protective film, and a common voltage applied to the liquid crystal cell. Electrode composition.

The manufacturing process of the color filter is as follows: First, a chromium/chromium oxide (Cr/CrOx) or an organic material used as a black matrix material is applied onto a glass substrate according to the use to form a pattern. After the black film pattern is formed, a pattern of a color photoresist for displaying colors is formed by photolithography. A color photoresist is applied onto the glass substrate, exposed, and the color photoresist is cured by photopolymerization. When the exposure is over, the portion of the color resist that is not exposed is removed by a developing process, and then the baking process is performed.

The color resist is produced by a pigment dispersion method, a dyeing method, an electrodeposition method, or the like, and the pigment dispersion method is most widely used. Usually, such as photoetching The photosensitive composition, that is, a photopolymerization initiator, a monomer, a binder, or the like, is dispersed with an organic pigment having a display color. The photopolymerization initiator is a highly sensitive compound which generates radicals after being subjected to light, and the monomer is polymerized by a radical, and then combined into a polymer to be in a state of being insoluble in a developing solvent. The binder protects the monomer in a liquid state from the developer under normal temperature conditions, and plays a role in determining the stability of the pigment dispersion and the reliability of heat resistance, light resistance, chemical resistance, and the like of the red, green, and blue patterns.

At present, after the color photoresist of the poor color filter substrate generated in the color filter process is cured once, it is not possible to perform refurbishment only by removing the erroneous pattern portion. Further, since the solvent capable of removing the color photoresist is hardly present, most of the defective color filters are generally discarded without being subjected to repeated operations such as trimming.

The color photoresist has the characteristics of a negative resist. Generally, the negative resist is difficult to peel off with respect to the positive resist, and therefore the negative resist needs to have strong peeling properties.

For the above reasons, a reactive ion etching (RIE) method using an inorganic stripping solution or an organic stripping solution and a plasma is used in the prior art. However, in the case of the organic stripping solution, the treatment time with respect to the inorganic stripping solution is long, and it is very difficult to peel off the coating material applied to the color filter. In the case of the inorganic stripping solution, it is inferior to the organic stripping solution, and the inorganic salt is precipitated from the solution for a long time, so that care must be taken when using it. The organic peeling solution is disclosed in Japanese Laid-Open Patent Publication No. SHO-51-72503, and the release agent is also disclosed in European Patent Publication No. 0119337. public.

Further, in order to solve the difficulty in performing the peeling in the organic stripping solution, some invention patents disclose a method of improving the properties of the peeling coating material by an inorganic salt which is easily soluble in an organic solvent, but the peeling time is compared with the inorganic stripping solution. There is still a certain gap. In the case of such an organic peeling solution, it is disclosed in Korean Patent Publication No. 2005-0006980.

In addition, a method of reactive ion etching (RIE) using plasma has been disclosed in U.S. Patent No. 5,756,239, by continuous use of oxygen reactive ion etching (O ₂ -RIE), hexafluoride. Sulfur-reactive ion etching (SF ₆ -RIE) is a method of removing a cured color photoresist which cannot be removed by a general wet etching method. In addition, U.S. Patent No. 5,059,500 discloses a method in which a polyester, a polyamidamine, a novolac resin is used as an absorption layer, and a mixture of polydecane, polyoxane, an organic phosphonium compound, vermiculite, and tantalum nitride is used. In the cured color resist used as the barrier layer, the absorption layer is removed by using a plasma of oxygen, and the barrier layer is removed by reactive ion etching using sulfur hexafluoride or nitrogen trifluoride. However, the etching of a color filter using such a plasma needs to be performed under conditions of high vacuum and high energy, and thus these conditions are difficult to grasp. In addition, the method has the disadvantage that it is difficult to use in a large area and the equipment is expensive.

As described above, the existing method of removing a color photoresist has the following disadvantages. That is, it is difficult to stably remove a large amount of color photoresist and coating material, lack safety, or reduce production efficiency or productivity.

Therefore, it is highly desirable to develop a method for removing a large amount of color photoresist by a safe method.

In order to solve the above technical problems, an object of the present invention is to provide a peeling solution composition capable of largely removing a color resist and a coating used in a color filter manufacturing process of a thin film transistor liquid crystal display by a safe method.

Another object of the present invention is to provide a color resist stripping solution composition capable of reusing a colored photoresist and a color filter substrate which are discarded after peeling.

In order to achieve the object, the present invention provides a color resist stripping solution composition comprising: (a) 1 to 20 weight percent selected from inorganic alkali hydroxides, ammonium hydroxide, having C ₁ -C ₄ alkane a hydroxide of a group of alkylammonium hydroxide or a phenylalkylammonium hydroxide having a C ₁ -C ₄ alkyl group; (b) from 1 to 70% by weight of an alkylene group having a C ₁ -C ₄ alkyl group At least one compound selected from the group consisting of an alkylene glycol ether or an alkylene glycol; (c) 0.5 to 10% by weight of hydroxylamine; (d) 0.5 to 50% by weight of an alkoxyalkylamine; and (e) The balance of water.

The composition may further comprise from 1 to 30% by weight of a dialkyleneglycol dialkylether having a C ₁ -C ₄ alkyl group or an alkylene glycol dialkyl ether And 0.05 to 10% by weight of the inorganic salt compound or at least one of 1 to 55% by weight of the polar solvent.

The color photoresist stripping solution composition of the present invention has the advantages that the color resist and the coating material can be easily removed in a short time, and subsequent It is not necessary to use an organic solvent such as isopropyl alcohol or dimethyl hydrazine in the rinsing step, and it is possible to wash it with water. In particular, since the color photoresist pattern can be removed, the color filter substrate can be reused.

The invention is described in detail below.

In order to remove color photoresists and coatings more effectively than in the prior art, and in order to reuse most of the discarded color filter substrates, the present inventors conducted repeated studies and found that it is possible to utilize a specific combination of stripping solution compositions. The present invention has been completed by easily removing colored photoresist and coating.

Hydroxide stripping solution composition used in the present invention may be selected from inorganic bases hydroxides, ammonium hydroxide, ammonium hydroxide having an alkyl C ₁ -C ₄ alkyl or C ₁ -C ₄ alkyl group having a compound of phenylalkylammonium hydroxide. Moreover, the color filter process is not greatly affected by the residual metal, and therefore an inorganic alkali hydroxide can also be used. The content of the hydroxide is preferably from 1 to 20% by weight based on the total composition, and if the content is less than 1% by weight, the penetration of the polymer component constituting the color resist is lowered, so that it is difficult to completely remove the colored light. Resistor. On the other hand, if it exceeds 20% by weight, the composition ratio of other solvents is reduced, which adversely affects the removal time. Further, since the alkylammonium hydroxide and the phenylalkylammonium hydroxide are not sufficiently stable, they are preferably used in a state of being dissolved in water.

Preferably, the inorganic alkali hydroxide is used in one or a mixture of two or more selected from the group consisting of lithium hydroxide, sodium hydroxide or potassium hydroxide. Preferably, the alkyl ammonium hydroxide having a C ₁ -C ₄ alkyl group is selected from the group consisting of tetraethyl ammonium hydroxide, tetramethyl ammonium hydroxide or tetrabutyl hydrogen. One or a mixture of two or more of tetrabutyl ammonium hydroxides. Further, as the phenylalkylammonium hydroxide having a C ₁ -C ₄ alkyl group, benzyltrimethyl ammonium hydroxide is preferably used.

At least one compound selected from the group consisting of alkylene glycol ethers or alkylene glycols having a C ₁ -C ₄ alkyl group, due to its solubility and reduction in color resists The surface tension is excellent, so that it can lower the surface tension between the glass surface and the colored photoresist lifted therefrom, so that the color resist can be easily peeled off, and the compound also has the effect of dissolving the stripped The function of a color resist for a binder or a polymer. The alkylene glycol ether is preferably used in an amount of from 1 to 70% by weight based on the total composition. In this case, if the content is less than 1% by weight, the color resist cannot be completely removed. Above 70% by weight, the polarity of the stripping solution is lowered, so that the ability to dissolve the coating material - acrylic resin or polyimide resin is decreased. Preferably, the alkylene glycol ether or alkylene glycol used in the present invention is selected from the group consisting of ethyleneglycol monobutylether and diethylene glycol monobutyl ether ( Diethylene glycol monobutylether), triethyleneglycol monobutylether, ethyleneglycol monomethylether, diethyleneglycol monomethylether, triethyleneglycol monomethylether ), ethyleneglycol monoethylether, ethylene glycol, diethylene glycol, triethylene glycol, hexylene glycol or glycerol ( One or a mixture of two or more of glycerol.

The hydroxylamine has a function of penetrating into a polymer constituting a color photoresist, separating a color photoresist from a glass substrate, and having a function of decomposing a pigment component. In other words, when the hydroxylamine is used together with a water-soluble amine, it provides a condition in which a hydorxyl radical or an aminium radical is easily formed, and thus a pigment component which is not easily soluble can be provided. It gradually decomposes and oxidizes, thus shortening the process time. The hydroxylamine is used in an amount of from 0.5 to 10% by weight based on the total composition. If the content is less than 0.5% by weight, the initial effect of the chemical solution cannot be maintained, and as a result, the service life is shortened; if it exceeds 10% by weight, the effect of shortening the process time cannot be achieved.

The alkoxyalkylamine has a function of penetrating into a polymer constituting a color photoresist and separating a color photoresist from a glass substrate. The alkoxyalkylamine is preferably from 0.5 to 50% by weight of the total composition. If the content of the alkoxyalkylamine is less than 0.5% by weight, the penetration force to the color resist is weakened, so that the color photoresist cannot be completely removed, and stratification with the inorganic alkali hydroxide occurs. If it is more than 50% by weight, the activity of the inorganic alkali metal ion is hindered, and its function cannot be improved. The alkoxyalkylamine may be selected from compounds having a C ₁ -C ₄ alkoxy group and an alkyl group, such as ethoxypropyl amine, methoxypropyl amine or methoxyB. One or a mixture of two or more of methoxyethyl amines.

Preferably, the water used in the present invention is pure water (deionized water) filtered through an ion exchange resin, and ultrapure water having a specific resistance of 18 (M?) or more is preferably used. The amount of water used may be a residual amount in the composition of the stripping solution, preferably from 4 to 49% by weight of the total composition. At this time, if the content of water is less than 4% by weight, the composition of the composition changes at the process temperature, and inorganic alkali ions are precipitated, thereby causing a storage period of the composition of the stripping solution for the color filter (pot life) Shortening; if it exceeds 49% by weight, the loss of the stripping solution composition for the color filter becomes large due to evaporation of water under the process temperature conditions.

Moreover, in order to enhance the function of removing the photoresist, the composition of the present invention may comprise from 1 to 30% by weight of a dialkylene glycol dihydrocarbyl ether or an alkylene glycol dihydrocarbyl group having a C ₁ -C ₄ alkyl group. An alkyleneglycol dialkylether, 0.5 to 50% by weight of a water-soluble amine other than the alkoxyalkylamine, 0.05 to 10% by weight of the inorganic salt compound, or at least one of 1 to 55% by weight of the polar solvent.

The dialkyleneglycol dialkylether having a C ₁ -C ₄ alkyl group and the alkyleneglycol dialkylether due to its solubility parameter (Solubility Parameter) and use as a coating material Since the acrylic resin or the imide resin is similar, it has a function of stably dissolving the coating polymer material peeled off from the glass substrate in the chemical solution. The dialkylene glycol dihydrocarbyl ether may be selected from the group consisting of dimethylene glycol dimethylether, diethyleneglycol dimethylether, diethyleneglycol diethylether. , diethyleneglycol dibutylether, diethyleneglycol dipropylether, dibutylene glycol dibutyl ether or dipropyleneglycol dimethylether One or a mixture of two or more. The alkylene glycol dialkyl ether may be selected from the group consisting of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether. (ethylene glycol dibutyl ether), ethylene glycol dipropyl ether (ethyleneglycol dipropylether) or a mixture of two or more.

Preferably, the dialkylene glycol dialkyl ether or alkyleneglycol dialkylether is used in an amount of from 1 to 30 weight percent of the total composition. At this time, if the content is less than 1% by weight, the function of peeling off the color photoresist and the coating material is lowered; if it exceeds 30% by weight, the activity of the inorganic alkali metal ion is inhibited and precipitation occurs, so the function is Can't get improved.

The water-soluble amine may be selected from the group consisting of n-methylmethanolamine, diethylamino propylamine, bis(2-methoxyethyl)amine, monoethanolamine (mono) One or a mixture of two or more of ethanolamine, ethylene diamine or mono methanolamine.

The inorganic salt used in the present invention, together with the hydrate Use can improve the effect of removing the photoresist. In particular, when an inorganic salt is used together with an alkylammonium hydroxide and a phenylalkylammonium hydroxide, the permeation and swelling characteristics of an acrylic resin and a polyimide resin as a coating material can be increased, thereby It has the advantage of significantly reducing the removal time. The inorganic salt is preferably used in an amount of from 0.05 to 10% by weight based on the total of the composition. At this time, if the content is less than 0.05% by weight, the effect of removing the coating material cannot be improved; if it exceeds 10% by weight, the maximum amount of residual water that can be contained in the stripping solution composition exceeds the saturation limit thereof, thereby The precipitation speeds up and causes problems with the equipment. The inorganic salt used in the present invention is preferably selected from the group consisting of potassium acetate, potassium nitrate, potassium carbonate, potassium pyrophosphate, potassium oleate, and benzoic acid. Potassium benzoate, potassium laurate, potassium tert-butoxide, potassium sulfate, potassium sorbate, potassium aminobenzoate, coke One or a mixture of two or more of potassium disulfate, potassium cyanate, potassium sulfide, potassium xylenesulfonate or sodium xylenesulfonate .

Further, the polar solvent used in the present invention is excellent in the penetrating power and solubility to the color resist, and therefore can penetrate between the polymers of the color resist to cause swelling. The polar solvent is preferably used in an amount of from 1 to 55 weight percent based on the total composition. At this time, if the content is less than 1% by weight, the time for completely removing the color photoresist is significantly longer; If it is more than 55 weight%, the solubility with the inorganic alkali hydroxide compound is lowered, and the performance cannot be improved. The polar solvent in the present invention is preferably selected from the group consisting of dimethylsulfoxide, diethylsulfoxide, dipropylsulfoxide, sulfolane, and n-methylpyrrolidone. One or a mixture of two or more of (n-methyl-2-pyrrolidone), pyrrolidone or n-ethyl pyrrolidone.

As described above, the present invention uses a specific content of the above-mentioned hydroxide, alkylene glycol ether, hydroxyl amine, water-soluble amine containing alkoxyalkylamine, dialkylene glycol II. a hydrocarbon ether or an alkyleneglycol dialkylether and water, and further using an inorganic salt compound and a polar solvent, thereby easily removing the color photoresist in a short time by multiplication of various components It is easy to remove the coating material, particularly the color photoresist pattern, so that most of the discarded color filter substrates can be recycled. Preferred compositions of the invention may comprise a hydroxide, an alkylene glycol ether, a hydroxylamine, an alkoxyalkylamine, a dialkylene glycol dialkyl ether or an alkane. A composition of a diol dihydrocarbyl ether, an inorganic salt, a polar solvent, and water.

Hereinafter, the present invention will be described in detail with reference to the following examples. These embodiments are merely exemplary embodiments of the invention, and the scope of the invention is not limited thereto.

Hereinafter, unless otherwise specified in the examples, the percentages and mixing ratios are based on the weight.

[Examples and Comparative Examples]

The components of the colored photoresist stripping solutions shown in the respective Examples and Comparative Examples were prepared by mixing the various components in the proportions shown in Tables 1 and 2.

[Experimental example]

The performance evaluation of the color resist stripping solution compositions shown in the above Examples 1 to 24 and Comparative Examples 1 to 3 was carried out by using the following engineering The color filter substrate was fabricated, and the color photoresist was subjected to the removal test as described below.

The sample was fabricated on a Corning glass having a chromium/chromium oxide (Cr/CrOx) deposited on its lower portion, and a color filter was formed in the order of red, green, and blue, respectively. The photolithography process is applied. A general color resist composition (manufactured by Tojin Seiken Co., Ltd., trade name: DCR-725S) was spin-coated, and the thickness of the final film was 1.7 μm. Then, the color photoresist film was pre-baked on a hot plate at a temperature of 90 ° C for 120 seconds. Then, it was exposed, and then developed with a 1% potassium hydroxide (KOH) developing solution under normal temperature for 60 seconds, and then the sample having formed the pattern was subjected to a temperature of 220 ° C for up to 20 in an oven. Hard baking for a minute.

After the color filter is completed on the sample, the coating material-polyimine or polyacrylic resin is applied to the sample by a spin coating method, and the final film thickness is reached. 3 μm. Then, the color photoresist film was pre-baked on a hot plate at a temperature of 90 ° C for 120 seconds. Then, it was exposed, and then developed with a 1% potassium hydroxide (KOH) developing solution at room temperature for 60 seconds, and then the sample in which the pattern was formed was subjected to a temperature of 220 ° C for 20 minutes in an oven. Hard baking.

Color photoresist removal test The prepared sample is immersed in a stripping solution composition for removing a color photoresist and a coating material at a temperature of 70 ° C, and a color photoresist and a coating are detected. The time from when the layer is completely stripped from the substrate. Next, the sample was taken out from the composition of the color photoresist stripping solution, washed with ultrapure water, and dried with nitrogen. Then, after expanding 100 times with an Olympus microscope, it was examined whether or not a color photoresist remained in the pattern, thereby observing whether or not a color photoresist remained in the substrate. Table 3 below shows the time taken after the coating material and the color resist were completely peeled off, and no residue was found.

As can be seen from the above Table 3, the performance of the color-removing agent of the embodiment of the present invention is excellent compared with the comparative example, and diethylene glycol dimethyl ether and ethoxypropylamine respectively play a role in improving the removal performance. . In particular, in the examples in which potassium salt, diethylene glycol dimethyl ether, ethoxypropylamine or the like was added, it was found that the performance was improved by 5 to 10 times.

In contrast, in Comparative Examples 1 and 2 in which no potassium salt was added, the removal performance was hardly improved. Further, in Comparative Example 3, since it did not contain an amine and an alkylene glycol ether compound, the peeling performance was also somewhat different.

Claims (9)

A color photoresist stripping solution composition comprising: a) 1 to 20 weight percent selected from an inorganic alkali hydroxide, ammonium hydroxide, an alkyl ammonium hydroxide having a C ₁ -C ₄ alkyl group or having C ₁ a hydroxide in the -C ₄ alkyl phenylalkylammonium hydroxide; b) from 1 to 70 weight percent of at least one selected from the group consisting of alkyl ether ethers or alkylene glycols having a C ₁ -C ₄ alkyl group a compound; c) 0.5 to 10% by weight of hydroxylamine; d) 0.5 to 50% by weight of alkoxyalkylamine; and e) balance of water; wherein the composition further comprises 0.05 to 10% by weight of inorganic a salt compound; wherein the inorganic salt is selected from the group consisting of potassium acetate, potassium nitrate, potassium pyrophosphate, potassium oleate, potassium benzoate, potassium laurate, potassium t-butoxide, potassium sulfate, potassium sorbate, potassium aminobenzoate, A compound in potassium pyrosulfate, potassium cyanate, potassium sulfide, potassium xylene sulfonate or sodium xylene sulfonate. The color resist stripping solution composition according to claim 1, wherein the inorganic alkali hydroxide is one or more selected from the group consisting of lithium hydroxide, sodium hydroxide or potassium hydroxide. mixture. The color resist stripping solution composition according to claim ₁ , wherein the alkyl ammonium hydroxide having a C ₁ -C ₄ alkyl group is selected from the group consisting of tetraethylammonium hydroxide and tetramethyl. One or a mixture of two or more of ammonium hydroxide, tetrabutylammonium hydroxide or benzyltrimethylammonium hydroxide; the phenylalkylammonium hydroxide having a C ₁ -C ₄ alkyl group is a benzyl group Methyl ammonium hydroxide. The color resist stripping solution composition according to claim ₁ , wherein the alkylene glycol ether or alkylene glycol having a C ₁ -C ₄ alkyl group is selected from the group consisting of ethylene glycol monobutyl Ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol One or a mixture of two or more of diethylene glycol, triethylene glycol, hexanediol or glycerol. The color resist stripping solution composition according to claim 1, wherein the alkoxyalkylamine is one selected from the group consisting of ethoxypropylamine, methoxypropylamine or methoxyethylamine. Or a mixture of two or more. The color resist stripping solution composition according to claim 1, wherein the composition further comprises from 1 to 30% by weight of a dialkylene glycol having a C ₁ -C ₄ alkyl group. a hydrocarbyl ether or an alkylene glycol dihydrocarbyl ether, 0.5 to 50% by weight of a water-soluble amine other than the alkoxyalkylamine or at least one component of 1 to 55 weight percent of a polar solvent. The color resist stripping solution composition according to claim 6, wherein the dialkyleneglycol dialkylether having a C ₁ -C ₄ alkyl group is selected from the group consisting of diamethylene glycol Dimethyl glycol glycol dimethylether, dibutylene glycol dibutyl ether, diethyleneglycol dimethylether, diethyleneglycol diethylether, One or a mixture of two or more of diethyleneglycol dibutylether, diethyleneglycol dipropylether or dipropyleneglycol dimethylether. The color resist stripping solution composition according to claim 6, wherein the water-soluble amine is selected from the group consisting of n-methylmethanolamine, monomethanolamine, monoethanolamine, and 1,2-ethanediamine. Or one or a mixture of two or more of diethylaminopropylamine or bis(2-methoxyethyl)amine. The color resist stripping solution composition according to claim 6, wherein the polar solvent is selected from the group consisting of dimethyl hydrazine, diethyl hydrazine, dipropyl fluorene, and cyclobutyl hydrazine. One or a mixture of two or more of n-methylpyrrolidone, pyrrolidone or n-ethylpyrrolidone.