KR20100045783A - Aqueous detergent composition - Google Patents

Abstract

PURPOSE: An aqueous detergent composition is provided to efficiently clean a contaminant on an alignment layer substrate with an improved moisturizing and permeating property. CONSTITUTION: An aqueous detergent composition without an alkali compound contains 0.1~15wt% of C1~C5 low alcohol, 0.1~15wt% of water-soluble glycolether compound, and water. The aqueous detergent composition is used before and after a rubbing process of an aligning layer for a liquid crystal display process. The C1~C5 low alcohol is selected from the group consisting of methanol, ethanol, n-propanol, isopropanol, ethylene glycol, 1,2- propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, glycerol and 1,2,4-butanetriol.

Description

Aqueous detergent composition

The present invention relates to an aqueous cleaning liquid composition used for semiconductors, display devices and the like. More specifically, the present invention relates to an aqueous cleaning composition of a substrate used before and after rubbing of a liquid crystal alignment film during a liquid crystal cell manufacturing process of a liquid crystal display.

In general, in the liquid crystal cell fabrication process, an alignment film is formed by applying a polyimide and rubbing it on a predetermined direction in order to provide the function of the alignment film and the insulating film on the two pattern substrates on which the electrode patterns are formed. Thereafter, a container of the liquid crystal cell is formed, a spacer is disposed and the two substrates are bonded to control the thickness of the seal adhesive and the liquid crystal cell. In this case, when the remaining contaminants are present on the alignment layer substrate into which the liquid crystal is injected, it is difficult to obtain a clear display screen and causes defects during packaging. Therefore, it is necessary to clean and remove the contaminants remaining on the substrate.

Contamination paths of substrates in the manufacture of liquid crystal cells of liquid crystal displays may include foreign substances or polyimide particles released from the rubbing cloth in the rubbing process before joining two PI substrates, which may adhere to the substrate and cause defects. Can be.

In order to remove such contaminants generated during the process, conventionally, a solvent or pure water such as isopropanol and isopropanol aqueous solution was used. However, cleaning with solvents causes solvents to remain on the substrate, leading to defects, and problems with chemical stability such as safety and flammability to the environment. It is causing an increase. In addition, pure water does not exhibit sufficient cleaning power for contaminants, which is accompanied by a decrease in production yield.

In addition, the cleaning agent containing an alkali compound causes a problem of damaging the PI alignment layer.

Japanese Patent Laid-Open No. 3-62018 proposes a method of stably forming a high pretilt angle by ultrasonic cleaning of a rubbing substrate with pure water. However, it is not easy to introduce ultrasonic waves into the display manufacturing process, and the method of cleaning with pure water does not satisfy the physical properties of the recently required cleaning agent.

Japanese Patent Laid-Open No. 3-81730 proposes a method of cleaning the surface of a rubbing substrate using a brush, but a cleaning effect cannot be expected due to secondary contaminations generated from the brush and reattachment to the substrate.

The above-described techniques are characterized by using a device that provides physical cleaning power to the cleaning process. This method not only increases the cost of the cleaning process, but also uses isopropanol and pure water to reduce solvent residue, rinse defects, It cannot be free from problems such as particle reattachment.

Therefore, in this field, in order to solve the problems as described above, a variety of water-based cleaning systems have been studied that are excellent in safety and work safety for the human body and excellent in cleaning power and rinsability by adding various surfactants. .

The present invention is to solve the above problems of the prior art, it is excellent in the wetting and penetrating effect, excellent cleaning effect for the contaminants present on the alignment film substrate, and does not cause damage to the alignment film, flammability It is an object of the present invention to provide a safe, environmentally friendly, low-aqueous aqueous cleaning composition.

The present invention is an aqueous washing liquid composition that does not contain an alkali compound, and comprises 0.1 wt% to 15 wt% of a lower alcohol of C1 to C5, 0.1 wt% to 15 wt% of a water-soluble glycol ether compound, and a residual amount of water based on the total weight of the composition. It provides an aqueous washing liquid composition characterized in that.

In addition, the present invention provides a liquid crystal cell including an alignment film washed with the aqueous cleaning liquid composition and a liquid crystal display device including the liquid crystal cell.

The water-based cleaning liquid composition of the present invention is excellent in the wetting and penetrating effect, excellent cleaning effect for the contaminants present on the alignment film substrate, does not cause damage to the alignment film, is not flammable, safe and environmentally friendly, The present invention does not cause a problem, and thus provides a very excellent effect in cleaning the substrate before and after rubbing of the liquid crystal alignment film during the liquid crystal cell manufacturing process of the liquid crystal display.

The present invention is an aqueous washing liquid composition that does not contain an alkali compound, and comprises 0.1 wt% to 15 wt% of a lower alcohol of C1 to C5, 0.1 wt% to 15 wt% of a water-soluble glycol ether compound, and a residual amount of water based on the total weight of the composition. It relates to an aqueous cleaning liquid composition characterized in that.

The aqueous cleaning liquid composition may be usefully used to clean the substrate before and after the rubbing process of the liquid crystal alignment layer of the liquid crystal cell manufacturing process of the display. In particular, the aqueous cleaning liquid composition may be usefully used for cleaning the polyimide alignment layer.

Alkaline compounds are used in general cleaning agents because of their ability to remove pollutants and organics in the air. However, even when a small amount of the alkali compound is contained, damage to the PI (polyimide) alignment layer may occur. Therefore, the cleaning liquid composition of this invention is characterized by not containing such an alkali compound.

In the water-based cleaning liquid composition of the present invention, the lower alcohol of C1 ~ C5 increases the wettability and penetration of the cleaning liquid to the substrate, improves the ability to prevent reattachment of the contaminants to facilitate the removal of contaminants from the substrate. When considering water solubility among the lower alcohols of C1 to C5, lower alcohols of C1 to C4 are preferable, and specific examples of lower alcohols of C1 to C4 include methanol, ethanol, n-propanol, isopropanol, ethylene glycol, and 1,2-. Propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, glycerol, 1,2,4-butanetriol, and the like. It may be used alone or two or more kinds together.

The lower alcohol content is preferably 0.1 to 15% by weight based on the total weight of the composition. If the content is less than 0.1% by weight it is difficult to expect the wet penetration because it does not drop the surface tension, if it exceeds 15% by weight may cause defects due to the solvent remaining on the substrate.

In the aqueous cleaning liquid composition of the present invention, the water-soluble glycol ether compound serves to remove oil components on the surface of the rubbing substrate, which are difficult to remove only by the lower alcohol aqueous solution, and improve the solubility in water. Among the water-soluble glycol ether compounds, C1 to C10 water-soluble glycol ethers are preferably used, and representative examples thereof include ethylene glycol monomethyl ether (MG), diethylene glycol monomethyl ether (MDG), and triethylene glycol monomethyl ether (MTG). ), Polyethylene glycol monomethyl ether (MPG), ethylene glycol monoethyl ether (EG), diethylene glycol monoethyl ether (EDG), ethylene glycol monobutyl ether (BG), diethylene glycol monobutyl ether (BDG), tree Ethylene glycol monobutyl ether (BTG), propylene glycol monomethyl ether (MFG), dipropylene glycol monomethyl ether (MFDG), and the like, and these may be used alone or in combination of two or more.

The content of the glycol ether is preferably 0.1 to 15% by weight, and if the content is less than 0.1% by weight, it is difficult to remove the oil component on the surface of the rubbing substrate. Adversely affect the wet penetration of

Although the water contained in the water cleaning composition of this invention is not specifically limited, It is preferable to use deionized water whose specific resistance value is 18 MPa / cm or more as water for a semiconductor process. The content of water can be adjusted according to the content of other components.

The aqueous washing liquid composition of the present invention may further include conventional additives known in the art to improve cleaning performance.

The components included in the aqueous washing liquid composition of the present invention can be prepared according to a conventionally known method, and it is particularly preferable to have a purity for semiconductor processing.

The present invention also relates to a liquid crystal cell comprising an alignment film washed with the aqueous cleaning composition and a liquid crystal display device including the liquid crystal cell. Using the water-based cleaner composition of the present invention, since the residual contaminants present on the alignment film substrate are completely removed, the liquid crystal cell including the alignment film has excellent quality. In addition, the liquid crystal display device including the liquid crystal cell can provide a clear display screen.

The cleaning method using the aqueous cleaning liquid composition of the present invention is not particularly limited, and an immersion cleaning method, oscillation cleaning method, ultrasonic cleaning method, shower / spray cleaning method, puddle cleaning method, brush cleaning method and the like can be applied.

The cleaning liquid of the present invention is a cleaning agent for substrates before and after rubbing of the liquid crystal alignment film during the liquid crystal cell manufacturing process of the liquid crystal display, and has excellent stability over time for cleaning performance and contamination of particles and the like present on the alignment film substrate. The material can be removed sufficiently. In addition, since no residue of the cleaning solution is generated, contaminants such as particles and the like are not re-adhered onto the substrate, and a problem of damage to the surface of the alignment film does not occur, it is possible to provide a safe cleaning system.

In addition, since the aqueous washing liquid composition of the present invention has a low foaming property, problems such as deterioration of workability due to bubbles that may occur in a process such as spraying do not occur.

Hereinafter, the present invention will be described in detail through examples. However, the following examples and the like are provided to explain the present invention in more detail, and the scope of the present invention is not limited thereto.

Examples 1-4 and Comparative Examples 1-3: Preparation of Cleaning Liquid Composition

The components shown in Table 1 were added to a mixing tank equipped with a stirrer according to a predetermined content, and stirred at a speed of 500 rpm for 1 hour at room temperature to prepare a cleaning liquid composition.

Test Example: Evaluation of Detergency and Damage of Alignment Film

1. Evaluation of cleaning power

100 ml of the cleaning solution composition prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were placed in a 250 ml beaker, and ultrasonic waves were applied for 1 minute immediately after supporting the substrate (5 × 5 × 0.7 cm) on which the polyimide alignment layer was rubbed. (40 kHz, 20 ° C) washing was performed. After washing for a while, the substrate was taken out and washed with ultrapure water for 30 seconds to rinse. The liquid on the surface of the substrate was removed with nitrogen gas, and then dried at 170 ° C. for 5 minutes in an oven. The board | substrate was inspected with the scanning electron microscope (SEM: Hitachi company, model name S-4700), and the washing | cleaning power was evaluated by the particle number of the foreign material which remained on the surface of a board | substrate. The results are shown in Table 1 below and FIGS. 1 and 2.

2. Evaluation of Damage to Polyimide Alignment Film

100 ml of the cleaning solution compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were placed in a beaker having a capacity of 250 ml, respectively, and the substrate having the polyimide alignment layer formed on glass was immersed for 30 minutes. The substrate was taken out, washed with water, dried with nitrogen gas, and dried, and the degree of damage of the polyimide alignment layer was visually observed and examined by scanning electron microscope (SEM: Hitachi, model name S-4700). The test results are shown in Table 1 below.

Alkali component Lower alcohol Glycol ether water Cleaning power PI damage Example 1 - IPA 5% by weight BDG 5% by weight Remaining amount ◎ none Example 2 - IPA 5% by weight MDG 5% by weight Remaining amount ◎ none Example 3 - IPA 1% by weight BDG 10% by weight Remaining amount ◎ none Example 4 - Ethanol 10% by weight BDG 5% by weight Remaining amount ◎ none Comparative Example 1 TMAH 0.5% by weight - - Remaining amount ◎ Complete peeling Comparative Example 2 - - BDG 20% by weight Remaining amount △ none Comparative Example 3 - - - Water (100%) × none

[Washing performance] ◎: Very good, ○: Good, △: Normal, ×: Poor

IPA: Isopropanol

MDG: Diethylene Glycol Monomethyl Ether

BDG: diethylene glycol monobutyl ether

TMAH: Tetra methyl ammonium hydroxide.

From the results shown in Table 1 above, it was confirmed that the cleaning liquid compositions of Examples 1 to 4 of the present invention all exhibit excellent cleaning power and did not cause damage to the polyimide alignment layer. On the other hand, the cleaning liquid composition of Comparative Example 1 containing a small amount of the alkali compound was completely impossible to use the PI alignment layer removed. In addition, although the cleaning liquid composition of Comparative Example 2 had a cleaning effect on foreign matters, organic substances remained on the substrate to form stains, resulting in a defect. In addition, the cleaning liquid composition of Comparative Example 3 made of pure water did not damage the polyimide alignment layer, but the cleaning power was low, resulting in a defect.

1 is a photograph taken with a scanning electron microscope (SEM) of a polyimide alignment layer substrate treated by the method of Test Example 1 using the cleaning solution of Example 1 of the present invention.

2 is a photograph taken with a scanning electron microscope (SEM) of a polyimide alignment layer substrate treated by the method of Test Example 1 using the cleaning solution of Comparative Example 3 of the present invention.

Claims (7)

An aqueous washing liquid composition that does not contain an alkali compound, comprising 0.1 wt% to 15 wt% of a lower alcohol of C1 to C5, 0.1 wt% to 15 wt% of a water-soluble glycol ether compound, and a balance of water based on the total weight of the composition Aqueous cleaning liquid composition. The water cleaning composition according to claim 1, wherein the water cleaning composition is used to clean the substrate before and after the rubbing process of the alignment layer during the liquid crystal display process. The lower alcohol of claim 1, wherein the lower alcohol of C 1 to C 5 is methanol, ethanol, n-propanol, isopropanol, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3 An aqueous washing liquid composition comprising at least one member selected from the group consisting of butanediol, 1,4-butanediol, glycerol and 1,2,4-butanetriol. The water-based washing liquid composition according to claim 1, wherein the water-soluble glycol ether is C1-C10 water-soluble glycol ether. The method of claim 1, wherein the water-soluble glycol ether is ethylene glycol monomethyl ether (MG), diethylene glycol monomethyl ether (MDG), triethylene glycol monomethyl ether (MTG), polyethylene glycol monomethyl ether (MPG), Ethylene glycol monoethyl ether (EG), diethylene glycol monoethyl ether (EDG), ethylene glycol monobutyl ether (BG), diethylene glycol monobutyl ether (BDG), triethylene glycol monobutyl ether (BTG), propylene glycol Aqueous cleaning liquid composition, characterized in that it is composed of one or more selected from the group consisting of monomethyl ether (MFG), and dipropylene glycol monomethyl ether (MFDG). A liquid crystal cell comprising an alignment film washed with the water-based cleaning composition of claim 1. Liquid crystal display device comprising the liquid crystal cell of claim 6.

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