JPH0798959B2 - Cleaning composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is used for manufacturing a liquid crystal display device, etc., and is excellent in stain removal property and rinsing property of liquid crystal, etc., and is safe and environmental pollutant like CFC. The present invention relates to a cleaning composition.

[Problems to be Solved by Prior Art and Invention]

In general, a liquid crystal display device uses a liquid crystal cell in which liquid crystal is filled between two substrates provided with electrodes on opposite surfaces, but it is clear that liquid crystal adheres to the outside of these two substrates. Not only is it impossible to obtain a good display screen, but it may also adversely affect other electronic components, so it must be removed.

Conventionally, Freon 113, 1,1,1-trichloroethane, etc. have been used to remove adhered liquid crystals, but these are limited in their use due to environmental problems such as destruction of the ozone layer in the sky and toxicity problems. Is being done. On the other hand, washing with sugars or alcohols does not have these problems, but the ability to remove liquid crystal stains is not sufficient.

Therefore, there has been a demand for a detergent composition which does not pollute the environment, has low toxicity, and is excellent in stain removability.

[Means for Solving the Problems]

In view of such actual circumstances, the present inventors have conducted diligent research and as a result, if a specific amount of a specific hydrocarbon and a surfactant is blended, there is no problem of environmental pollution and toxicity, and excellent stain removability, and further The present invention has been completed by finding that a detergent composition having a good rinsing property can be obtained.

That is, the present invention provides a detergent composition containing at least 50% by weight of an alkylbenzene or olefin having 8 to 20 carbon atoms and a viscosity of 0.5 to 10 cp at 20 ° C., and 0.01 to 50% by weight of a surfactant. It is a thing.

The alkylbenzene or olefin used in the present invention has 8 to 20 carbon atoms and has a viscosity at 20 ° C. of 0.5 to 10 c.
that is p. If the alkylbenzene or olefin has a carbon number of less than 8 or a viscosity of less than 0.5 cp, the flammability is high and safety during cleaning becomes a problem.
On the other hand, if the carbon number exceeds 20 or the viscosity exceeds 10 cp, the cleaning of the narrow gap is not sufficient, which is not preferable. A particularly preferred viscosity range is 0.5-5 cp.

In the present invention, the alkylbenzenes include various linear alkylbenzenes such as xylene, ethylbenzene, diisopropylbenzene, cumene, p-cymene, branched alkylbenzenes, etc., and the olefins include octene, decene, dodecene, tetradecene, hexadecene, eicosene, Examples thereof include linear or branched ones such as tetrapropylene, tetraisobutylene and hexapropylene. The olefin having 12 to 18 carbon atoms is particularly preferable.

These alkylbenzenes or olefins are incorporated in the composition of the present invention in an amount of 50% by weight or more, preferably 60 to 68% by weight. If it is less than 50% by weight, it is not preferable because the cleaning property is poor.

As the surfactant used in the present invention, any of anionic, cationic, zwitterionic and nonionic surfactants can be used, but the nonionic surfactant is less in effect on the cleaning surface. Is the best. Specifically, polyoxyalkylene alkyl ether, polyoxyalkylene alkylphenol ether, polyoxyalkylene alkyl fatty acid ester, polyoxyalkylene allylphenol ether, polyoxyalkylene sorbitan fatty acid ester, polyoxyalkylene alkylamine, sorbitan fatty acid ester, polyoxyalkylene Etc. Among them, nonionic surfactants having an average HLB of 4 to 15 exhibit particularly excellent effects. Here, polyoxyalkylene refers to a polymer of ethylene oxide, propylene oxide or butylene oxide.

The amount of the surfactant added is preferably about 0.01 to 50% by weight, particularly 3 to 40% by weight. If it is less than 0.01% by weight, the effect of detergency due to the addition of the surfactant does not appear.
If it exceeds 5% by weight, the surfactant may remain on the cleaning surface and affect the properties of the cleaned part.

Further, the cleaning composition of the present invention may further contain various alcohols such as ethanol and glycol; esters such as acetoacetic acid, methyl oleate, and benzyl acetate; You may mix | blend antioxidant, a corrosion inhibitor, water etc.

The detergent composition of the present invention can be produced by mixing by a conventional method.

The method of cleaning the liquid crystal using the cleaning composition of the present invention is not particularly limited, for example ultrasonic cleaning using the cleaning composition of the present invention, immersion cleaning, and finally a method of rinsing with a solvent or warm water. A method of continuously performing the above is an efficient cleaning method. Further, various cleaning methods such as a vibration method and a spray method may be used.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these.

Example 1 A glass plate having a thickness of 1.1 mm was provided with a spacer, and another glass plate was placed on the spacer to form a sandwich structure having a gap of 10 to 20 μm, and a liquid crystal (ZLI-1565, manufactured by Merck Jampin Co. Make a cell.

This cell was immersed in the cleaning solution shown in Table 1 at 40 ° C. for 1 minute, and then ultrasonically cleaned in the same solution for 5 minutes. Then, the residual liquid crystal on the glass plate of the cell and around the cell was measured with a polarizing microscope, and the cleaning property was evaluated according to the following evaluation criteria. Next, the cell was taken out from the cleaning liquid, immersed in an ion exchange tank at 40 ° C. for 1 minute, the rinsing property was measured with a polarizing microscope, and evaluated according to the following evaluation criteria.

The results are shown in Table 1.

(Evaluation Criteria) Liquid crystal removability ◎: Very good with no liquid crystal residue ○: Almost good without liquid crystal residue △: Slightly poor liquid crystal residue, somewhat bad ×: Poor liquid crystal residue Rinse ◎: Very good Excellent: Good: Fair: Somewhat poor ×: Poor [Effects of the Invention] The cleaning composition of the present invention has excellent cleaning power and rinsing property against liquid crystal adhered to glass substrates, jigs, tools, etc. or stains containing it, and further does not use CFCs or the like. Therefore, it does not pollute the environment and is highly safe.

Claims (2)

[Claims] 1. A detergent composition for liquid crystals, containing 50% by weight or more of an alkylbenzene or olefin having 8 to 20 carbon atoms and a viscosity of 0.5 to 10 cp at 20 ° C., and 0.01 to 50% by weight of a surfactant. object. 2. The cleaning composition for liquid crystals according to claim 1, wherein the surfactant is a nonionic surfactant having an average HLB of 4 to 15.