JP2821384B2 - Azeotropic composition comprising fluorinated ether and ethanol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azeotropic composition and an azeotropic composition, and more particularly, to an azeotropic composition and an azeotropic composition used as flux washing, degreasing washing, draining and drying, and a solvent. -Like compositions.

[0002]

2. Description of the Related Art Conventionally, halogenated hydrocarbons are the most well-known solvents for cleaning electronic parts, precision machine parts, resin processed parts, etc., and chlorine atoms or carbon atoms obtained by substituting chlorine atoms for fluorine atoms. It has characteristics as a hydrogen group. These halogenated hydrocarbons are less toxic,
High substitution number of halogen shows nonflammability and is chemically and thermally stable, and has appropriate solubility to dissolve waxes and oils without eroding the surface of plastics and rubber. Therefore, it is widely used in various industrial fields. For example, these halogenated hydrocarbons include chlorinated hydrocarbons such as trichloroethylene, tetrachloroethylene and 1,1,1-trichloroethane, and 1,1,2-trichloro-1,2,2-trifluoroethane (Freon 113). Are particularly known, and the latter is used in a wide range of fields because of its low toxicity, nonflammability, and chemical and thermal stability.

[0003] However, such a chlorofluorocarbon-based hydrocarbon or 1,1,1-trichloroethane has a chlorine atom, and thus has a serious drawback of destroying the ozone layer in the stratosphere, and its production and use have been stopped. It is determined internationally. In addition, trichlorethylene and tetrachlorethylene have been designated as Class 2 Specified Chemical Substances since 1989 based on the results of surveys on the status of environmental pollution and the findings of harmful effects of chronic toxicity, etc. Designated. Under such circumstances, the development of such chlorofluorocarbon-based hydrocarbons and substances that substitute for chlorinated hydrocarbons has been actively conducted.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has excellent properties such as the detergency and low toxicity of chlorofluorocarbon-based hydrocarbons and chlorine-based hydrocarbons. It is an object of the present invention to provide a novel composition which is not damaged and does not have to worry about depletion of the ozone layer.

[0005]

According to the present invention, there is provided a difluoromethyl 2,2,3,
An azeotropic composition and an azeotropic composition comprising 3-tetrafluoropropyl ether and ethanol are provided.

[0006] The composition of the present invention comprises difluoromethyl
2,2,3,3-tetrafluoropropyl ether
47-67 mol% and ethanol 33-53 mol%, preferably difluoromethyl 2,2,3,3-
Tetrafluoropropyl ether 52-62 mol%
And 38 to 48 mol% of ethanol, and more preferably 56.37 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 43.63 mol% of ethanol. The boiling point of this azeotropic composition is 67.degree. At atmospheric pressure (760 mmHg).
33 ° C. It is desired that the washing solvent and the draining and drying solvent have no change in composition even when they are recycled by distillation or the like. Compositions of the present invention in the above ranges are those whose vapor composition resulting from evaporation or distillation is the same or nearly identical to the composition of the liquid mixture, and whose composition does not change or changes only negligibly. do not do.

Difluoromethyl 2,2,3,3-tetrafluoropropyl ether is a known substance, for example, by reacting chlorodifluoromethane with 2,2,3,3-tetrafluoropropanol in the presence of potassium hydroxide. Obtained easily.

The composition according to the present invention may further contain various stabilizers when used under severe conditions. As the stabilizer, those which are entrained by distillation or those which form an azeotropic mixture are desirable. Specific examples of such a stabilizer include aliphatic nitro compounds such as nitromethane and nitroethane; aromatic nitro compounds such as nitrobenzene and nitrostyrene; dimethoxymethane;
-Dimethoxyethane, 1,4-dioxane, 1,3,5
Ethers such as trioxane, glycidol, methyl glycidyl ether, allyl glycidyl ether, phenyl glycidyl ether, 1,2-butylene oxide,
Epoxys such as cyclohexene oxide and epichlorohydrin; unsaturated hydrocarbons such as hexene, heptene, pentadiene, cyclopentene and cyclohexene; olefinic alcohols such as allyl alcohol and 1-buten-3-ol; 3-methyl-1-butyne -3-ol,
Acetylene alcohols such as 3-methyl-1-pentyn-3-ol and the like, and acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate and vinyl methacrylate are exemplified. In order to further obtain a synergistic stabilizing effect, phenols, amines and benzotriazoles may be used in combination. These stabilizers may be used alone or in combination of two or more. The amount of the stabilizer used depends on the type of the stabilizer and the like, but is set to such an extent that the azeotropic property is not hindered. The amount used is usually about 0.01 to 10% by weight of the composition of the present invention, and more preferably about 0.1 to 5% by weight.

Further, various surfactants can be added to the composition of the present invention, if necessary, in order to further improve detergency, interfacial action and the like. Surfactants include sorbitan monooleate, sorbitan fatty acid esters such as sorbitan trioleate, polyoxyethylene sorbite fatty acid esters such as polyoxyethylene sorbite tetraoleate, and polyethylene glycol fatty acids such as polyoxyethylene monolaurate. Esters, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene alkylphenyl ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene alkylamine fatty acid amides such as polyoxyethylene oleic amide, etc. Nonionic surfactants may be used alone or in combination of two or more. For the purpose of synergistically improving the detergency and the interfacial action, a cationic surfactant or an anionic surfactant may be used in combination with these nonionic surfactants. The amount of the surfactant to be used varies depending on the kind and the like, but it is an amount which does not hinder the azeotropic property, and is usually 0.1% of the composition of the present invention.
About 20% by weight, more preferably about 0.3 to 5% by weight.

The composition of the present invention can be widely used for known washing and drying applications. In particular, it can be used as a flux detergent, a washing solvent, a degreasing detergent and a draining desiccant. It is extremely useful as a substitute for 1-trichloroethane. Specific applications include flux, grease, oil, wax, and ink removers, electronic components (printed circuit boards, liquid crystal displays, magnetic recording components, semiconductor materials, etc.), electrical components, precision mechanical components,
Examples include detergents for resin-processed parts, optical lenses, clothing, and the like, and drainers and desiccants. As the cleaning method, a conventionally used method such as immersion, spraying, boiling cleaning, ultrasonic cleaning, steam cleaning, or a combination thereof can be adopted.

Further, the composition of the present invention can be used for various uses such as a solvent for a paint, an extractant, a heat medium and a foaming agent, similarly to the conventional chlorofluorocarbon.

[0012]

The following examples are provided to further clarify the features of the present invention. Of course, the present invention is not limited by these examples.

[0013]

[Reference Example 1] Synthesis of difluoromethyl 2,2,3,3-tetrafluoropropyl ether Potassium hydroxide was placed in a 200 ml stainless steel reactor equipped with a stirrer, a pressure gauge, a thermometer, a gas inlet tube and a gas outlet tube. 2.0g (0.713mol) and 2,2,3,3
-165.2 g of tetrafluoropropanol (1.2
5 mol) and closed. Then, after the air in the reactor was removed, chlorodifluoromethane in a cylinder connected to a gas introduction pipe was injected into the reactor (with a pressure of up to 7.0 kg / cm ² G) while stirring. Thereafter, the temperature inside the reactor was gradually increased by external heating while stirring, and the temperature was maintained at about 90 to 100 ° C. As the reaction progresses,
The pressure in the reactor dropped. Therefore, the pressure inside the reactor is increased to 7.0 kg / cm every predetermined time.
^The operation of injecting until ² G was reached was repeated. Then, when the pressure drop hardly occurred (15 hours), stirring was stopped, and the reactor was cooled to around 0 ° C. The total charge of chlorodifluoromethane was 27.4 g (0.317 m
ol). After the pressure in the reactor was returned to the atmospheric pressure, the lid of the reactor was opened, and the reaction solution was poured into excess ice water. The separated organic layer was further washed with excess ice water, dried over anhydrous sodium sulfate, and then distilled under atmospheric pressure to obtain difluoromethyl 2,2,3,3-tetrafluoropropyl ether (99% or more in purity). (Boiling point about 75 ℃) 3
2.2 g were obtained.

[0014]

[Reference Example 2] Measurement of vapor-liquid equilibrium and measurement of azeotropic point Measurement was performed using a gas wave equilibrium measuring device. A mixed sample having a constant composition of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and ethanol was placed in a sample container and heated. The heating was adjusted so that the dropping rate of the vapor-phase condensate became appropriate, and stable boiling was maintained for 40 minutes or more. After ensuring that the pressure and boiling point were stable, they were measured. The liquid phase and the gas phase condensate were sampled, and the composition of the sampled solution was analyzed by gas chromatography. Table 1 and FIG.
Shown in

In FIG. 1, the vertical axis represents temperature (° C.), and the horizontal axis represents the concentration (molar fraction) of difluoromethyl 2,2,3,3-tetrafluoropropyl ether.

From these results, it was found that difluoromethyl 2,2
2,3,3-tetrafluoropropyl ether 47-
Compositions of the invention in the range of 67 mol% and 33 to 53 mol% ethanol have a composition in which the vapor produced by evaporation or distillation is or almost identical to the composition of the liquid mixture and the composition varies. Azeotropic and azeotrope-like compositions that do not or only change negligibly. Where difluoromethyl 2,2,3,3-
56.37 mol% of tetrafluoropropyl ether
And 43.63 mol% of ethanol,
An azeotropic composition whose boiling point is atmospheric pressure (760 mmH
g) is 67.33 ° C.

[0017]

[Table 1]

[0018]

Example 1 A flux washing test was carried out using a composition comprising 56.37 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 43.63 mol% of ethanol.

Test piece (SUS-316; 50 mm
× 10 mm × 1 mm) in a flux [GX-8S manufactured by Asahi Chemical Laboratory Co., Ltd.]
Heat treatment was performed at 0 ° C. for 1 minute. The test piece was ultrasonically cleaned in the above composition for 1 minute and then dried with warm air. When the state of flux removal was observed with the naked eye, it was found that the flux had been successfully removed.

[0020]

Example 2 The procedure of Example 1 was repeated except that the composition of Example 1 was replaced by a composition comprising 65 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 35 mol% of ethanol. When a test was conducted in the same manner, it was confirmed that the flux could be removed well.

[0021]

Example 3 Example 1 was repeated except that a composition consisting of 50 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 50 mol% of ethanol was used instead of the composition of Example 1. When a test was conducted in the same manner, it was confirmed that the flux could be removed well.

[0022]

Example 4 An attached water removal test was conducted using a composition comprising 56.37 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 43.63 mol% of ethanol.

A glass plate (30 mm
× 20 mm × 1 mm) in pure water, and then in the mixed solvent composition for 30 seconds. The removed glass plate was allowed to stand at room temperature for 1 minute to evaporate the remaining composition, then immersed in anhydrous methanol, and the increase in the water content of the methanol was measured by a Karl Fischer moisture meter. On the other hand, from the comparison with the increase in water content of methanol when not immersed in the mixed solvent composition but only immersed in pure water, the removal state of the attached water was examined. It was found that when immersed in water, attached water could be almost completely removed.

[0024]

Example 5 The procedure of Example 4 was repeated except that the composition of Example 4 was replaced by a composition comprising 65 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 35 mol% of ethanol. A similar test showed that the attached water could be almost completely removed.

[0025]

Since the composition of the present invention does not contain chlorine atoms, there is no fear of destruction of the ozone layer. Further, since the composition of the present invention contains a hydrogen atom, it has high reactivity with hydroxyl radicals in the atmosphere and is easily decomposed in the troposphere, so that the greenhouse effect is small.

[Brief description of the drawings]

FIG. 1 is a vapor-liquid equilibrium curve of a difluoromethyl 2,2,3,3-tetrafluoropropyl ether-ethanol system.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C11D 7/50 C11D 7/50 C23G 5/032 C23G 5/032 (73) Patent holder 000002200 Central Glass Co., Ltd. Ube City, Yamaguchi Prefecture 5253 Okibe (73) Patent holder 000000044 Asahi Glass Co., Ltd. 2-1-2 Marunouchi, Chiyoda-ku, Tokyo (73) Patent holder 000174851 Mitsui Dupont Fluorochemical Co., Ltd. 1-5-18 Sarugakucho, Chiyoda-ku, Tokyo (73) Patent holder 000003300 Tosoh Corporation 4560 Kaisei-cho, Shinnanyo-shi, Yamaguchi (74) The above six agents Patent attorney Kazuo Shamoto (5 outside) (72) Inventor Akira Sekiya Higashi, Tsukuba, Ibaraki 1-Chome First Industrial Technology Research Institute of Materials Science and Technology (72) Inventor Shiro Yamashita Hongo Wakai 2-40-17 Hongo 2-chome, Bunkyo-ku, Tokyo 6th floor of building New Technology Refrigerant Project Office, Global Organization for Industrial Technology Research Institute (72) Inventor Haruaki Ito 2-40-17, Hongo, Bunkyo-ku, Tokyo Hongo Wakai Building 6th floor 6th Floor of Global Environmental Industry Research Institute New Generation Refrigerant Project Room (72) Inventor Yoshihiko Goto 2-40-17 Hongo, Bunkyo-ku, Tokyo Hongo Wakai Building 6F New Generation Refrigerant Project Room (72) Inventor Suga Atsushi 2-40-17 Hongo, Bunkyo-ku, Tokyo Hongo Wakai Building 6F Inside the New Generation Refrigerant Project Office, Research Organization of Environmental Technology, Japan (72) Inventor Yuji Mochizuki 2-40-17 Hongo, Bunkyo-ku, Tokyo Hongo Wakai Building 6F Hongo Wakai Building 6F Hongo Wakai Bldg. 6F, Hongo Wakai Bldg. Surgery New Generation refrigerant project chamber examiner Tomo Fujimori Ichiro (58) investigated the field (Int.Cl. ^6, DB name) C07C 43/12 B01D 12/00 C07C 31/08 C11D 7/26 C11D 7/28 C11D 7 / 50 C23G 5/032 CA (STN) CAOLD (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. An azeotropic composition comprising difluoromethyl 2,2,3,3-tetrafluoropropyl ether and ethanol. 2. The azeotropic composition according to claim 1, comprising 47 to 67 mol% of difluoromethyl 2,2,3,3-tetrafluoropropyl ether and 33 to 53 mol% of ethanol. 3. A cleaning solvent comprising the composition according to claim 1. 4. A solvent for draining and drying, comprising the composition of claim 1.