JP2010143971A - Detergent composition and method for cleaning liquid crystal panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detergent composition which can clean both liquid crystal dirt and a cutting scrap such as polyimide (a foreign substance on a terminal) at the same time, and has good liquid stability; and to provide a method for cleaning a liquid crystal panel using the same. <P>SOLUTION: The detergent composition used for cleaning a liquid crystal panel includes (A) an organic alkali, (B) a hydrocarbon, and (C) a surfactant selected from a group consisting of a polyoxyalkylene alkyl ether and a sulfosuccinic acid-type anionic surfactant, and has pH of ≥8.5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning composition suitable for cleaning a liquid crystal panel and a method for cleaning a liquid crystal panel.

The liquid crystal panel is usually partially opened so that a pair of glass substrates on which a film-like electrode using indium tin oxide (ITO) or the like and an alignment film using polyimide (PI) or the like are formed face each other. Leave the alignment films together with an adhesive to create a liquid crystal chamber, inject liquid crystal into the liquid crystal chamber, seal the opening with a sealant, perform cleaning, and deflect to the surface of each glass substrate It is manufactured by sticking each plate.
Moreover, in a liquid crystal panel, many electrode terminals for applying a voltage between electrodes are arrange | positioned at the outer peripheral end surface of a glass substrate.

In the manufacture of a liquid crystal panel, it is inevitable that a gap (narrow portion) is generated outside the bonding portion between the pair of glass substrates (on the side opposite to the liquid crystal chamber side) due to a narrow gap between the opposing glass substrates. When liquid crystal is injected into the liquid crystal chamber, the liquid crystal enters the narrow portion due to capillary action and adheres.
If the liquid crystal adhering to the narrow portion (hereinafter referred to as “liquid crystal stain”) is left as it is, the residue of the liquid crystal stain acts as a mold release agent, so that the deflection plate is peeled off in the subsequent manufacturing process. There is a risk of various problems such as poor connection of the driver terminal, defects at the driver underfill interface, and peeling of the peelable coating film used in the substrate thinning method.

Hydrocarbon, an organic solvent, is excellent for cleaning this liquid crystal stain. Conventionally, an organic solvent such as a hydrocarbon, or a semi-aqueous system in which an organic solvent such as a hydrocarbon and a surfactant or glycol ether are combined. Alternatively, a method using an aqueous cleaning agent is generally used as a cleaning method for liquid crystal stains.
For example, an aqueous liquid detergent composition for a liquid crystal panel comprising a hydrocarbon compound having 8 to 20 carbon atoms, an anionic surfactant, an alkylene oxide adduct of a specific medium-chain branched primary alcohol, and a predetermined amount of water. The thing is proposed (refer patent document 1). According to such a cleaning composition, in addition to liquid crystal stains, it is also possible to remove glass chips (cullet) generated when cutting a glass substrate from a mother glass, which adheres to the electrode terminals using liquid crystal stains as a binder. ing.
JP 2004-002691 A

By the way, in the liquid crystal panel, the alignment film using polyimide or the like is rubbed on the surface in order to align liquid crystal molecules in a certain direction with respect to the electrode surface.
During this rubbing process, shavings such as polyimide are generated. If the shavings of polyimide or the like adhere to the electrode terminal, various troubles may occur in the subsequent manufacturing process as in the case of the liquid crystal stain described above.

  For this reason, in the manufacturing of liquid crystal panels, it is necessary to clean and remove shavings such as polyimide in addition to liquid crystal stains.

An alkali is generally used for dissolving polyimide. However, in the invention described in Patent Document 1, alkali is not used, and in the technique described in Patent Document 1, even though the cullet attached to the electrode terminal using liquid crystal stain as a binder can be removed, polyimide or the like can be used. It was difficult to remove shavings with high cleanliness.
In addition, even if an alkali is simply added to the cleaning composition in Patent Document 1, the alkali and the hydrocarbon compound are not easily compatible with each other and become cloudy, so that the liquid stability has a uniform and transparent appearance. It is difficult to prepare a simple composition. When a liquid crystal panel is washed using this white turbid cleaning composition, a dispersion in the composition may remain on the liquid crystal panel, resulting in poor cleaning.

Therefore, when trying to clean both the liquid crystal stains adhering to the liquid crystal panel and the shavings such as polyimide, a cleaning process aimed at removing liquid crystal stains and a cleaning process aimed at removing shavings such as polyimide Must be performed separately.
On the other hand, it is desired that both stains can be cleaned simultaneously by a single cleaning process.

  The present invention has been made in view of the above circumstances, and is capable of simultaneously cleaning both liquid crystal stains and shavings such as polyimide (hereinafter referred to as “foreign matter on the terminal”), and has a good liquid stability. It is an object of the present invention to provide a composition and a method for cleaning a liquid crystal panel using the cleaning composition.

As a result of intensive studies, the present inventors provide the following means in order to solve the above problems.
That is, the present invention is a cleaning composition used for cleaning a liquid crystal panel, selected from the group consisting of an organic alkali (A), a hydrocarbon (B), a polyoxyalkylene alkyl ether, and a sulfosuccinic acid type anionic surfactant. And a surfactant (C) having a pH of 8.5 or higher.

In the cleaning composition of the present invention, the acid dissociation index (pKa) of the organic alkali (A) is preferably 7 to 10. Moreover, it is preferable to use 2 or more types of the said organic alkali (A) together.
Moreover, in the cleaning composition of this invention, it is preferable that pH is 9 or more.
Moreover, in the cleaning composition of this invention, it is preferable to further contain the acid (D) whose acid dissociation index (pKa) is 4-7.

  The liquid crystal panel cleaning method of the present invention is characterized by using the cleaning composition of the present invention.

According to the cleaning composition of the present invention, both the liquid crystal stain and the foreign matter on the terminal can be cleaned at the same time, and the liquid stability is good.
In addition, according to the method for cleaning a liquid crystal panel of the present invention, both liquid crystal stains adhering to the gap (narrow part) of the liquid crystal panel and shavings (foreign matter on the terminal) such as polyimide adhering to the electrode terminal are removed. Thorough washing and removal can be achieved by one washing process.

<Cleaning agent composition>
The cleaning composition of the present invention is used for cleaning a liquid crystal panel, and is composed of an organic alkali (A), a hydrocarbon (B), a polyoxyalkylene alkyl ether, and a sulfosuccinic acid type anionic surfactant. The selected surfactant (C) is contained, and the pH is 8.5 or more.

[Organic alkali (A)]
In the present specification and claims, “organic alkali” includes organic compounds having basic properties.
In the present invention, by containing the organic alkali (A) (hereinafter referred to as “component (A)”), a good detergency can be obtained mainly for the foreign matter on the terminal. In addition, a detergent composition having a uniform and transparent appearance and good liquid stability can be prepared.

(A) A component is not specifically limited, Especially, what has an acid dissociation index (pKa) of 7-10 is preferable, and what has pKa of 7.5-9.5 is more preferable. When the pKa is 7 to 10, after preparing the cleaning composition, the liquid stability is better and the pH fluctuation is small. In addition, a plurality of cleaning processes can be performed with the same cleaning liquid, and the same cleaning liquid can be used repeatedly. In the present specification, the characteristic of continuing to use the same cleaning liquid repeatedly is hereinafter referred to as “detergency stamina”.
Moreover, it becomes easy to maintain pH of a cleaning composition in desired pH as pKa is the range of 7-10.

In the present specification and claims, the “acid dissociation index (pKa)” is the negative common logarithm (−log Ka) of the equilibrium constant (acid dissociation constant, Ka) of the dissociation reaction in which hydrogen ions are released from the acid. ). The alkali with a larger pKa is stronger in basicity.
The value of the acid dissociation index (pKa) is listed in the third edition of the chemical handbook basic edition edited by the Chemical Society of Japan (published by Maruzen Co., Ltd.).

Examples of the component (A) include monoethanolamine (pKa9.5), diethanolamine (pKa8.87), triethanolamine (pKa7.76), ethylenediamine (pKa9.92 and 7.12), diaminopropane (pKa10.53). And 8.84), triaminopropane (pKa9.86, 8.07 and 3.72), dimethylamine (pKa11.02), triethylamine (pKa10.68), tetramethylammonium hydroxide, tetraethylammonium hydroxide, water An example is tetra-n-butylammonium oxide.
Of these, monoethanolamine, diethanolamine, and triethanolamine are preferred because they have excellent cleaning power stamina as well as cleaning power against foreign matter on the terminal.

(A) A component can be used individually by 1 type or in combination of 2 or more types as appropriate.
Among these, the component (A) preferably has a pKa of 7 to 10, and particularly preferably two or more types having a pKa of 7 to 10 are used in combination. Detergency stamina improves further by using 2 or more types of this (A) component together.
The proportion of the component (A) in the cleaning composition of the present invention is preferably 0.01 to 20% by mass, more preferably 0.1 to 15% by mass, and 1 to 12% by mass. More preferably.
(A) The cleaning power with respect to the foreign material on a terminal improves more as the ratio of a component is more than a lower limit. Moreover, the liquid stability of a cleaning composition improves more. Moreover, the pH fall with time can be suppressed, and the detergency stamina improves.
If the ratio of (A) component is below an upper limit, the increase in the viscosity of a cleaning composition will be suppressed and handling property and the rinse property after washing | cleaning will improve. In particular, in the case of a cleaning process using an ultrasonic cleaner, an increase in the viscosity of the cleaning composition is suppressed and the cleaning power is further improved.

[Hydrocarbon (B)]
In the present invention, by containing the hydrocarbon (B) (hereinafter referred to as “component (B)”), a good detergency can be obtained mainly against liquid crystal stains.
Component (B) preferably has 8 to 16 carbon atoms, more preferably 10 to 14 carbon atoms, and still more preferably 12 to 14 carbon atoms.
When the carbon number is 8 to 16, particularly 10 to 14, the detergency against liquid crystal stains is further improved. In addition, when the carbon number is not less than the lower limit, the flammability is low, and when the carbon number is not more than the upper limit, the solubility of the component (B) itself is good, and the cleaning composition has a uniform and transparent appearance. It becomes easy to obtain.

The component (B) is not particularly limited as long as it is a hydrocarbon compound, and examples thereof include paraffin, paraffin hydrocarbon, and olefin hydrocarbon.
Specific examples of the component (B) include n-decane, n-dodecane, n-tetradecane, isodecane, isododecane, and olefins corresponding to these paraffins.
Among these, paraffins having 12 to 14 carbon atoms and olefins having 12 to 14 carbon atoms are more preferable because they have a relatively high boiling point and are not easily flammable and have excellent solubility in liquid crystals.

  In the present invention, as the component (B), for example, commercially available products such as normal paraffin N12D (trade name) manufactured by Japan Energy and Dialene 12 (trade name) manufactured by Mitsubishi Chemical Corporation can be used.

(B) A component can be used individually by 1 type or in combination of 2 or more types as appropriate.
The proportion of the component (B) in the cleaning composition of the present invention is preferably 1 to 80% by mass, and more preferably 1 to 70% by mass.
When the ratio of the component (B) is equal to or higher than the lower limit, the detergency against liquid crystal stains is further improved. If the ratio of (B) component is below an upper limit, the rinse property after washing | cleaning will improve. In addition, the flammability becomes lower.

[Surfactant (C)]
In the present invention, a surfactant (C) selected from the group consisting of a polyoxyalkylene alkyl ether (hereinafter referred to as (C1) component) and a sulfosuccinic acid type anionic surfactant (hereinafter referred to as (C2) component) By containing (C) component, the effect of improving the cleaning power against liquid crystal stains and foreign matter on the terminal is mainly obtained. Moreover, the effect of the liquid stability improvement which exhibits a uniform and transparent external appearance is acquired.

-Polyoxyalkylene alkyl ether (C1) In the present specification and claims, the component (C1) includes those having a carbon chain having 8 or more carbon atoms (for example, the carbon chain is represented by the following general formula: ^{R 1} is applicable in the compounds represented by (c1-1)).
Examples of the component (C1) include those obtained by adding an alkylene oxide to a higher alcohol (preferably an alcohol having 8 to 18 carbon atoms). Especially, since the liquid stability and the rinse (rinse) property after washing | cleaning are more favorable, the compound represented by the following general formula (c1-1) is mentioned as a suitable thing.

［式中、Ｒ^１は炭素数８〜１８のアルキル基又はアルケニル基であり、ＡＯはオキシアルキレン基であり、ｎはアルキレンオキシド単位の平均付加モル数で２〜３０の数である。］

[Wherein, R ¹ is an alkyl group or alkenyl group having 8 to 18 carbon atoms, AO is an oxyalkylene group, and n is an average added mole number of alkylene oxide units of 2 to 30. ]

In the formula (c1-1), R ¹ is an alkyl group having 8 to 18 carbon atoms or an alkenyl group having 8 to 18 carbon atoms, and the alkyl group or alkenyl group may be linear. It may be branched.
R ¹ has 8 to 18 carbon atoms, and is preferably 8 to 15 and more preferably 8 to 10 because of good liquid stability and rinsing properties after washing.

In the formula (c1-1), AO is an oxyalkylene group, and specific examples thereof include oxyethylene group, oxypropylene group, and oxybutylene group. Detergency or liquid stability or rinse after rinsing (rinse) ), The oxyethylene group and the oxypropylene group are more preferable.
In said formula (c1-1), n is a number of 2-30, and since the detergency or liquid stability is favorable, it is more preferable that it is a number of 4-20.

In the present invention, the component (C1) is, for example, the Neugen XL series (trade name; carbon number of R ¹ , type in which AO is an oxyethylene group) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Names: commercially available products such as R ¹ having 8 carbon atoms and AO being an oxyethylene group) can be used.

About the sulfosuccinic acid type anionic surfactant (C2), the component (C2) includes, for example, sulfosuccinate, and in particular, since the liquid stability and the rinsing property after washing are better, A compound represented by the following general formula (c2-1) is preferable.

［式中、Ｒ^２は炭素数３〜２２のアルキル基若しくはアルケニル基であり；Ｒ^３は炭素数３〜２２のアルキル基若しくはアルケニル基、アルカリ金属原子、アルカリ土類金属原子、アンモニウム又はアルカノールアミンであり；Ｑ^１は−Ｏ−又は−ＮＨ−であり、Ｍはアルカリ金属原子、アルカリ土類金属原子、アンモニウム又はアルカノールアミンである。］

[Wherein R ² represents an alkyl group or alkenyl group having ³ to 22 carbon atoms; R ³ represents an alkyl group or alkenyl group having ³ to 22 carbon atoms, an alkali metal atom, an alkaline earth metal atom, ammonium, or an alkanolamine. Q ¹ is —O— or —NH—, and M is an alkali metal atom, alkaline earth metal atom, ammonium or alkanolamine. ]

In the formula (c2-1), R ² is an alkyl group having 3 to 22 carbon atoms or an alkenyl group having 3 to 22 carbon atoms, and the alkyl group or alkenyl group may be linear. It may be branched.
R ² has 3 to 22 carbon atoms and is preferably 6 to 16 and more preferably 8 to 12 because of good liquid stability and rinsing properties after washing.

In the formula (c2-1), R ³ is an alkyl group having ^{3 to} 22 carbon atoms, an alkenyl group having 3 to 22 carbon atoms, an alkali metal atom, an alkaline earth metal atom, ammonium (NH ₄ ), or an alkanolamine. is there.
The alkyl group and alkenyl group in R ³ may be linear or branched.
The number of carbon atoms of the alkyl group or alkenyl group is 3 to 22, and it is preferably 6 to 16 and preferably 8 to 12 because of good liquid stability and rinsing properties after washing. Is more preferable.
Examples of the alkali metal atom in R ³ include sodium and potassium.
Examples of the alkaline earth metal atom in R ³ include calcium and magnesium.
Examples of the alkanolamine in R ³ include monoethanolamine, diethanolamine, and triethanolamine.

In the formula (c2-1), Q ¹ is —O— or —NH—, preferably —O—.
In the formula (c2-1), M represents an alkali metal atom, an alkaline earth metal atom, ammonium or alkanolamine, and examples thereof are the same as those exemplified for R ³ above. Among these, an alkali metal atom is preferable.

As the component (C2), dioctyl sulfosuccinate is preferable among the above.
In the present invention, as the component (C2), for example, a commercially available product such as Lion's Ripar 870P (trade name) can be used.

(C) A component can be used individually by 1 type or in combination of 2 or more types as appropriate.
The proportion of the component (C) in the cleaning composition of the present invention is preferably 1 to 30% by mass, and more preferably 10 to 25% by mass.
When the proportion of the component (C) is at least the lower limit value, the liquid stability is particularly improved. Further, the cleaning power against liquid crystal stains and foreign matter on the terminals is further improved. If the ratio of (C) component is below an upper limit, the effect of improvement of liquid stability and a detergency will fully be acquired. Moreover, the rinse property after washing | cleaning improves.

[Acid (D)]
The cleaning composition of the present invention preferably further contains an acid (D) having an acid dissociation index (pKa) of 4 to 7 (hereinafter referred to as “component (D)”). By containing (D) component, pH stabilization after preparing a cleaning composition can mainly be aimed at, and detergency stamina property improves.
(D) pKa of a component is 4-7, and it is preferable that it is 5-7. When the pKa is 7 or less, the detergency stamina is improved. If pKa is 4 or more, the pH drop with time can be suppressed, and the effect of improving detergency stamina can be sufficiently obtained.

Examples of the component (D) include citric acid (pKa 5.69, 4.35 and 2.90), benzoic acid (pKa 4.00), acetic acid (pKa 4.76), and succinic acid (pKa 5.20 and 3.99). Is mentioned.
Of these, citric acid and benzoic acid are preferred because the effect of stabilizing the pH after preparing the cleaning composition is good.

  In the present invention, as the component (D), for example, commercially available products such as citric acid (crystal) (trade name; citric acid monohydrate) manufactured by Komatsuya Chemical, and PuroxB (trade name) manufactured by DSM are used. Can do.

(D) A component can be used individually by 1 type or in combination of 2 or more types as appropriate.
The proportion of the component (D) in the cleaning composition of the present invention is preferably 0.01 to 3% by mass, and more preferably 0.1 to 1.5% by mass.
When the proportion of the component (D) is at least the lower limit, the effect of stabilizing the pH after preparing the cleaning composition is further improved. When the proportion of the component (D) is not more than the upper limit value, the effect of improving the liquid stability is further improved.

[Other ingredients]
In the cleaning composition of this invention, you may use together other components other than said (A)-(D) component as needed.
Examples of other components include water, a liquid crystal dissolution aid, and a liquid stabilizer.

  Examples of the liquid crystal dissolution aid include organic solvents other than the component (B). For example, phenyl glycol, dimethyl sulfoxide (DMSO) and the like can be used.

The liquid stabilizer is, for example, R ⁴ O— (A′O) _m —R ⁵ [wherein R ⁴ is an alkyl group or alkenyl group having 1 to 6 carbon atoms; R ⁵ is a hydrogen atom or a methyl group] A′O is an oxyalkylene group, and m is a number from 1 to 5. ] The compound represented by this is mentioned.
In the above formula, R ⁴ is an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 1 to 6 carbon atoms, and the alkyl group and alkenyl group may be linear or branched. There may be.
A′O is an oxyalkylene group, preferably an oxyethylene group.

The cleaning composition of the present invention has a pH of 8.5 or higher and preferably a pH of 9 or higher. The upper limit of the pH is preferably 10.5 or less, and more preferably 10 or less.
When the pH of the cleaning composition is 8.5 or more, preferably 9 or more, good cleaning power can be obtained particularly for foreign matter on the terminal. In addition, the detergency stamina is improved. When the pH is preferably 10.5 or less, more preferably 10 or less, corrosion of the metal member of the liquid crystal panel is suppressed.
In the present invention, pH is measured using a pH meter (product name: D-51, manufactured by Horiba, Ltd.) and a pH electrode (product name: 9611-10D, manufactured by Horiba, Ltd.) at 25 ° C. It is carried out by immersing the pH electrode in the agent composition and reading the indicated value after 15 seconds.

  The method for preparing the cleaning composition of the present invention is not particularly limited, and can be prepared by sequentially mixing the components according to a conventional method. The blending order of each component may be arbitrary, and it is preferable to add each component little by little and prepare while stirring.

As described above, according to the cleaning composition of the present invention, both the liquid crystal stain and the foreign matter on the terminal attached to the liquid crystal panel can be cleaned simultaneously by a single cleaning process. In addition, the cleaning composition of the present invention has a uniform and transparent appearance and good liquid stability.
Moreover, according to the cleaning composition of the present invention, the same cleaning liquid can be used for multiple cleaning treatments, and the same cleaning liquid can be used repeatedly (excellent in cleaning power stamina).
Moreover, according to the cleaning composition of this invention, corrosion of the metal member of a liquid crystal panel can be suppressed.
The cleaning composition of the present invention is suitable for cleaning a liquid crystal panel.

<Cleaning method of LCD panel>
The liquid crystal panel cleaning method of the present invention is a method using the above-described cleaning composition of the present invention.
The cleaning method is not particularly limited. For example, a method of spraying and wiping a cleaning composition directly onto a liquid crystal panel, which is an object to be cleaned, from a nozzle or the like; a method of immersing a liquid crystal panel in a cleaning composition And a method of performing ultrasonic treatment at the time of washing.
In the liquid crystal panel cleaning method of the present invention, a method of performing ultrasonic treatment at the time of cleaning is preferable. By performing ultrasonic cleaning treatment on the liquid crystal panel using the cleaning composition of the present invention, it is possible to effectively clean both liquid crystal stains adhering to the liquid crystal panel and foreign matter on the terminal in a short time. Can do.
According to the method for cleaning a liquid crystal panel of the present invention, both the liquid crystal stain and the foreign matter on the terminal attached to the liquid crystal panel can be sufficiently cleaned and removed by a single cleaning process.
Such a cleaning method is suitable for cleaning a liquid crystal panel.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. “%” Means “% by mass” unless otherwise specified.

<Preparation of cleaning composition>
(Examples 1-11, Comparative Examples 1-5)
According to the composition shown in Tables 1 and 2, according to a conventional method, the detergent composition of each example was prepared by stirring while adding each component little by little so that the total amount becomes 100% by mass.
In addition, the unit of the compounding quantity in a table | surface is the mass%, and all the compounding quantities of each component show the amount equivalent of pure content.
Below, the component shown in the table | surface is demonstrated.

[Description of components shown in the table].
・ Organic alkali (A)
MEA: monoethanolamine, reagent grade, manufactured by Kanto Chemical; pKa 9.5.
DEA: diethanolamine, reagent grade, manufactured by Kanto Chemical; pKa 9.12.
TEA: triethanolamine, reagent grade, manufactured by Kanto Chemical; pKa 7.76.

-Component (A) comparative component [hereinafter referred to as "(A ') component". ]
NaOH: Sodium hydroxide, reagent, manufactured by Pure Chemical; pKa13 or higher.

・ Hydrocarbon (B)
Dodecane: Cactus normal paraffin N12D (trade name), manufactured by Japan Energy.
Dodecene: Dialene 12 (trade name), manufactured by Mitsubishi Chemical.

・ Surfactant (C)
C8E4: polyoxyethylene octyl ether, ethylene oxide (EO) 4 mol adduct; New Coal 1004 (trade name), manufactured by Nippon Emulsifier.
C8E20: polyoxyethylene octyl ether, EO 20 mol adduct; New Coal 1020 (trade name), manufactured by Nippon Emulsifier.
C10E4: polyoxyethylene decyl ether, EO4 mol adduct; Neugen XL-40 (trade name), manufactured by Daiichi Kogyo Seiyaku.
C10E14: polyoxyethylene decyl ether, EO14 mol adduct; Neugen XL-140 (trade name), manufactured by Daiichi Kogyo Seiyaku.
AOT: Sodium di-2-ethylhexylsulfosuccinate, Lipar 870P (trade name), manufactured by Lion.

・ Acid (D)
Citric acid: citric acid monohydrate, citric acid (crystal) (trade name), manufactured by Komatsuya Chemical; pKa 5.69, 4.35 and 2.90.
Benzoic acid: Purox B (trade name), manufactured by DSM, imported from the Netherlands; pKa 4.00.

Other components Phenyl glycol: PhG (trade name), manufactured by Nippon Emulsifier.
C6E2: Hexyl diglycol (trade name), manufactured by Nippon Emulsifier.
water

<Measurement of pH of cleaning composition>
The pH of the stock solution of the cleaning composition obtained by the above <Preparation of cleaning composition> was measured.
The pH was measured using a pH meter (product name: D-51, manufactured by HORIBA, Ltd.) and a pH electrode (product name: 9611-10D, manufactured by HORIBA, Ltd.) on a cleaning composition at 25 ° C. On the other hand, the pH electrode was immersed, and the indicated value after 15 seconds had elapsed was read.

<Evaluation of cleaning power against liquid crystal stains and foreign matter on terminals>
[Preparation of sample to be cleaned]
A liquid crystal material for a TFT liquid crystal panel was injected into a gap (narrow portion) of the liquid crystal panel using a syringe to prepare a sample to be cleaned.
In addition, as the liquid crystal panel, a film in which polyimide alignment films were bonded together with an adhesive so that a pair of glass substrates in which an indium tin oxide (ITO) electrode and a polyimide alignment film were laminated in this order was opposed to each other. . On the electrode terminal of the liquid crystal panel, the one in which polyimide shavings (foreign matter on the terminal) was adhered to such an extent that it could be confirmed with an optical microscope was used.

[Cleaning test]
As an ultrasonic cleaner, SC-20 type (product number: 50 kHz, 200 W) manufactured by Sun Electronics Industry Co., Ltd. was used.
A stock solution of the cleaning composition of each example was placed in the ultrasonic cleaner, the sample to be cleaned was immersed in the stock solution, and ultrasonic cleaning was performed at 40 ° C. for 16 minutes.
Subsequently, the sample to be cleaned is taken out, and ion-exchanged water at room temperature is put into the ultrasonic cleaning machine prepared separately, and the sample to be cleaned is immersed in the ion-exchanged water, and the cleaning time is set to 10 minutes. Was subjected to an ultrasonic rinsing process under the same conditions as the ultrasonic cleaning process using the stock solution of the cleaning composition.
Thereafter, the sample to be cleaned was taken out, placed in a constant temperature dryer, and dried at 80 ° C. for 20 minutes.
After completion of drying, using a polarizing microscope (product number: BX-60, Olympus Kogyo Co., Ltd.), the remaining state of the liquid crystal material in the narrow part of the sample to be cleaned and the remaining state of the polyimide on the electrode terminal are as follows. Evaluation was performed based on the evaluation criteria. The results are shown in Tables 1 and 2.
(Evaluation Criteria for Detergency) ◎ to ○ are acceptable ranges ◎: Completely removed.
○: Almost removed.
Δ: A little removed.
X: It was not removed at all.
In addition, in the table | surface, "-" shows that it was not evaluated since it had become cloudy immediately after preparing a cleaning composition.

<Evaluation of liquid stability>
After the cleaning composition of each example was prepared, it was stored separately under conditions of room temperature (25 ° C.) and high temperature (50 ° C.), and the appearance of the cleaning composition after 1 day was evaluated as follows. Based on the evaluation. The results are shown in Tables 1 and 2.
(Evaluation criteria for liquid stability) ◎ to ○ are acceptable ranges ◎: Both room temperature and high temperature exhibited a uniform and transparent appearance.
○: A uniform and transparent appearance was exhibited at room temperature, and it was cloudy at high temperature.
Δ: Both room temperature and high temperature were cloudy.
X: It became cloudy immediately after preparation of a cleaning composition (room temperature).

<Evaluation of detergency stamina>
1000 mL of the stock solution of the cleaning composition of each example was placed in a 1000 mL beaker, placed in a water bath, and stored for one week and one month.
During storage, the beaker was not covered, and the temperature was raised to 50 ° C. for 8 hours during the day for stirring, and the remaining 16 hours were left without stirring at room temperature. The cleaning composition continued to be used during the storage period without being replaced.
Using the cleaning composition after one week and after one month, the cleaning power against the foreign matter on the terminal is evaluated by the same method as the above <Evaluation of cleaning power against liquid crystal stains and foreign matter on the terminal>. Based on the following evaluation criteria, the cleaning power stamina was evaluated. The results are shown in Tables 1 and 2.
(Evaluation criteria for detergency stamina) ◎◎ to ○ are acceptable.
A: Completely removed both after one week and after one month.
A: Completely removed after one week, and almost removed after one month.
○: Almost removed after one week, and a little removed after one month.
Δ: A little removed after one week, but not removed after one month.
X: It was not removed at all after one week and after one month.

From the above results, the cleaning compositions of Examples 1 to 11 of the examples according to the present invention were liquid crystal stains attached to the gap (narrow part) of the liquid crystal panel, and scrapes such as polyimide attached on the electrode terminals (terminals) It was confirmed that both of the upper foreign matter) could be washed at the same time and the liquid stability was good.
Moreover, it has also confirmed that the cleaning composition of 1-11 of the Example which concerns on this invention was excellent in the detergency stamina property.

Claims (6)

In the cleaning composition used for cleaning the liquid crystal panel,
An organic alkali (A),
Hydrocarbon (B),
A surfactant (C) selected from the group consisting of polyoxyalkylene alkyl ethers and sulfosuccinic acid type anionic surfactants, and
A cleaning composition having a pH of 8.5 or more.   The cleaning composition according to claim 1, wherein the organic alkali (A) has an acid dissociation index (pKa) of 7 to 10.   The cleaning composition according to claim 2, wherein two or more of the organic alkalis (A) are used in combination.   The cleaning composition according to any one of claims 1 to 3, wherein the pH is 9 or more.   The detergent composition according to any one of claims 1 to 4, further comprising an acid (D) having an acid dissociation index (pKa) of 4 to 7.   A cleaning method for a liquid crystal panel, wherein the cleaning composition according to claim 1 is used.