JPH01165698A - Azeotropic solvent composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to an azeotrope consisting of 1,1,2-)sachloro-1,2,2-trifluoroethane (hereinafter referred to as Freon-113) and ethyl formate. The present invention relates to solvent compositions.

[Conventional technology] Freon-113, a chlorofluoroethane compound, is nonflammable and has low biotoxicity, and has the ability to dissolve oils, fats, grease, wax, etc. without attacking polymeric substances such as plastics and rubber. It has excellent selective solubility, and is widely used in solvents, detergents, etc., either alone or in combination with other organic solvents, or in the form of azeotropic compositions.

[Problems to be solved by the invention] In recent years, it has become clear that chlorofluoroethane compounds (hereinafter referred to as varhaloethane), in which all hydrogen has been replaced with chlorine and fluorine, such as Freon-113, are destroying the ozone layer surrounding the earth. Environmental pollution has become a problem, and there is an urgent need to reduce the use of perhaloethane.

Various substances have been studied to replace Freon-113, but no effective substitute has yet been found. On the other hand, mixed solvents of Freon-113 and other organic solvents have also been put into practical use.

However, in order to use it as a solvent, it is important that it be easy to manage the liquid during use, and that it can be easily recovered and reused, and it is also desired that it be able to be cleaned with steam. A mixed solvent that satisfies these requirements cannot be obtained simply by mixing two or more components, but must be a mixture that has an azeotropic point, that is, an azeotropic mixture.

Azeotropic mixtures with methanol and ethanol are known as azeotropic mixtures with Freon-113, but in both cases the alcohol content is less than 10% (wt%, the same applies hereinafter) (methanol: 6%, ethanol). :4%), therefore, it is not satisfactory in terms of reducing the amount of Freon-113 used.

Also, 1:1 of Freon-113 and methylene chloride
Although azeotropic mixtures have also been put into practical use, they are not desirable due to the high biotoxicity of methylene chloride.

The present invention provides an azeotropic solvent composition that can further improve the wax cleaning ability of Freon-113 and reduce the amount of Freon-113 used.

[Means for solving the problems] The azeotropic solvent composition of the present invention contains 82.1% Freon-11.
3 and 17.9% ethyl formate.

[Function and Examples] Freon-113 used in the present invention (boiling point: 47.6°C)
The azeotropic mixture of and ethyl formate (boiling point = 54d℃) is 44
．． It has an azeotropic point of 5°C.

Traditionally, ethyl formate has only been used to a limited extent as a special solvent, and its properties as a cleaning agent are not particularly known. It also has a considerable effect on rubber, making it difficult to wash items containing such polymeric materials.

According to the present invention, Freon-113 and ethyl formate are combined into 82
．． Freon-1 because it contains it at a weight ratio of 1/17.9
Not only can the amount of 13 used be significantly reduced, but the impact on plastics and rubber can be suppressed, so the items to be cleaned can be washed completely, and the ability to dissolve waxes such as paraffin wax can also be improved. can.

Furthermore, since it is in an azeotropic state, liquid management, recovery, and reuse are easy, and it can also be applied to steam cleaning, and it is safe because it is nonflammable.

Although the composition of the present invention is chemically relatively stable, stabilizers may also be added.

Preferable properties for such a stabilizer include, of course, having a large stabilizing effect on the composition of the present invention, but also those that are entrained in distillation operations and those that form an azeotrope. These are desirable, but not limited to.

Specific examples of the above-mentioned stabilizers include aliphatic nitro compounds such as nitromethane, nitroethane, and nitropropane, 3-methyl-1-butyn-3-ol,
- Acetylene alcohols such as methyl-1-pentyne-3-ol, glycidol, methyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, epoxides such as 2-butylene oxide, cyclohexene oxide, epichlorohydrin, dimethoxymethane, 1.2-dimethoxyethane, 1.4-
Dioxane, 1.3.5-) Ethers such as dioxane, hexene, heptene, octene, 2.4.4-)
Unsaturated hydrocarbons such as dimethyl-1-pentene, pentadiene, octadiene, cyclohexene, cyclopentene, allyl alcohol, ■-buten-3-ol, 3
- Olefinic alcohols such as methyl-1-buten-3-ol, methyl acrylate, ethyl acrylate,
Examples include acrylic esters such as butyl acrylate, and these may be used alone or in combination of two or more. In addition, these and phenol, trimethylphenol, cyclohexylphenol, thymol, 2.6-
Phenols such as di-t-butyl-4-methylphenol, butylhydroxyanisole, isoeugenol, hexylamine, pentylamine, dipropylamine, diisopropylamine, diisobutylamine, triethylamine, tributylamine, pyridine, N-methylmorpholine, Cyclohexylamine, 2.2.6.8
-tetramethylpiperidine, N,N'-diallyl-p-
Amines such as phenylenediamine, benzotriazole, 2-(2'-hydroxy-5°-methylphenyl)
It may be used in combination with triazoles such as benzotriazole and chlorobenzotriazole, and when used in combination, an even more excellent synergistic stabilizing effect is exhibited.

The amount of the stabilizer to be used cannot be determined unconditionally since it varies depending on the type of stabilizer, but it is usually preferably used in an amount of 0.1 to 10%, and 0.5 to 10%, based on the composition of the present invention.
It is more preferable to use 5%.

The azeotropic solvent composition of the present invention, which has these advantages, can be used not only to remove oil and grease, but also to remove temporary fixing waxes during processing such as cutting and polishing of silicon wafers, crystals, and ceramics used for semiconductors. It is useful as a cleaning agent.

Next, the azeotropic solvent composition of the present invention will be explained with reference to Examples, but the present invention is not limited to these Examples.

Example 1 300 g of a mixture of 150 g and 150 g of Freon-113 and ethyl formate, respectively, was placed in a distillation flask and distilled under normal pressure using a rectification column with 30 theoretical plates. As a result, an azeotrope was observed at 44.5°C, and when the fraction was analyzed by gas chromatography, the composition was 82.1% Freon-113 and 17.9% ethyl formate.
%Met.

Example 2 The solubility of waxes used as temporary fixing materials in silicon wafer processing was investigated in the following manner.

100 g of each of the solvents shown in Table 1 was placed in a 200 cc beaker and heated to 40°C. Then, while stirring, powdered waxes such as Flatlow wax, Yellow wax, and Bruf wax (all manufactured by Nikka Seiko ■) were gradually added to the mixture, and the solubility was observed.

The results are shown in Table 1.

Solubility evaluation was performed according to the following criteria.

◎: Wax concentration 2% or more dissolved O: Wax concentration 1% or more dissolved up to 2% Δ: Wax concentration dissolved up to 1% ×: Not dissolved Example 3 Effects on the material (plastic) for each solvent shown in Table 1 (Degree of swelling) was examined in the following manner.

100% of the solvent shown in Table 1 in a 100cc pressure-resistant glass bottle
g and the plastic test piece shown in the same table (5 x 50 x 2
mm) and left in a constant temperature bath at a temperature of 50° C. for 4 hours, and after taking it out, the weight increase and volume increase were immediately examined.

The results are shown in Table 1.

Evaluation ◎Double weight or volume increase 0-1% 08 Weight or volume increase 1-3% △: Double amount or volume increase 3-5% ×: Weight or volume increase of 5% or more And so.

[Effects of the Invention] The azeotropic solvent composition of the present invention can reduce the amount of fluorocarbon-113 used, which is considered to be a cause of ozone layer destruction in fluorocarbon-based solvents, and can also reduce the amount of fluorocarbon-113 and ethyl formate. It is an extremely excellent solvent composition that exhibits a harmonious dissolving power, is nonflammable, and has the advantages of an azeotrope, such as ease of handling during liquid management, recovery, and reuse. Furthermore, it has the excellent effect of expanding the range of substances to be dissolved.

Patent applicant: Daikin Industries, Ltd.

Claims (1)

[Claims] 1 An azeotropic solvent composition consisting of 82.1% by weight of 1,1,2-trichloro-1,2,2-trifluoroethane and 17.9% by weight of ethyl formate.