JP2978309B2 - Azeotropic composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to highly fluorinated hydrofluorocarbon-based compositions which exhibit azeotropic or near-azeotropic behavior. More specifically, in addition to being used for degreasing and cleaning of grease and processing oil used for metal parts as a processing and rust inhibitor, and for removing flux at the time of semiconductor production, a foaming agent, a working medium,
The present invention relates to an azeotrope-like composition capable of replacing uses such as an electric insulating agent.

[0002]

2. Description of the Related Art Chlorofluorocarbons have low toxicity, are flame retardant, and are chemically and thermally stable, so they are widely used as solvents, blowing agents, refrigerants, etc., and are used for cleaning semiconductor products such as flux removal. Is a chlorofluorocarbon solvent, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113, boiling point about 48 ° C.), or a chlorine solvent, 1,1,1-
Trichloroethane and the like were used.

[0003]

[Problems to be Solved by the Invention] However, from the viewpoint of protection of the ozone layer, CFC-11 (trichlorofluoromethane) and CFC-12 (dichlorodifluoro For chlorofluorocarbons such as methane), CFC-113, CFC-114, and CFC-115, reductions in production and usage restrictions were implemented. Carcinogenicity has also been pointed out for chlorinated solvents, and the use of such solvents has been studied in view of problems such as groundwater contamination. Accordingly, an object of the present invention is to provide a composition that exhibits an azeotropic or similar behavior based on a novel chlorine-free hydrofluorocarbon that has no risk of destroying the ozone layer and has no problem of carcinogenicity. And

[0004]

The azeotropic composition according to the present invention comprises 70 to 99% by weight of 1,1,1,2,3,4,4,5,5,5-decafluoropentane ( HFC-43-10mee) and 30 to 1% by weight of n-hexane.

HFC-43-10mee used in the examples had a boiling point of 54.7
° C. Commercially available solvent-grade n-hexane can be used.

When HFC-43-10mee having a boiling point of 54.7 ° C. is used,
The composition of the present invention exhibited a minimum boiling point of 47.1 ° C. in a composition consisting of 86.7% by weight of HFC-43-10mee and 13.3% by weight of n-hexane, as evident from Example 1 below.

[0007] The composition of the present invention is a composition exhibiting an azeotropic or near-behavioral behavior. Therefore, even if a distillation operation is performed in the use process, the composition change is small, so that the properties of the composition can be maintained. This is convenient for the recovery and reuse of substances, and the solubility of hydrocarbons is improved as compared with the case of using only decafluoropentane.

In the azeotrope-like composition of the present invention, nitroalkanes, epoxides, furans, and the like, which have been conventionally used as a stabilizer for chlorofluorocarbons, may be contained.
At least one selected from benzotriazoles, phenols, amines, and phosphates may be contained. The amount of the stabilizer is based on the azeotropic composition.
It is 0.01 to 5% by weight, preferably 0.05 to 0.5% by weight.

The flammability of the azeotropic composition of the present invention is n-
The flash point of hexane alone has increased significantly, and safety has improved.

[0010] Specifically, the cleaning agent is used for removing contaminants such as fluxes, oils and fats, buffing abrasives and the like, cleaning agents for metal parts, plastic parts, rubber products, precision machine parts and electronic parts combining these parts. Also, it is used as a cleaning agent for dry cleaning. When used as a cleaning agent, wipe off with a room temperature cleaning method, dipping, brushing,
Flashing, spraying, ultrasonic cleaning, immersion in a boiling state by a heat cleaning method, steam rinsing, steam cleaning, and the like can be applied, and when these are combined, it is more effective.

The azeotrope-like composition of the present invention can be used for various applications such as a foaming agent, a working medium, a solvent for fluoropolymer polymerization, an electric insulating agent, etc., in addition to a conventional chlorofluorocarbon.

Hereinafter, the present invention will be described in detail with reference to examples.

[0013]

Example 1 A flask (500 ml) was charged with 400 g of a mixture comprising 90% by weight of HFC-43-10mee (boiling point: 54.7 ° C.) and 10% by weight of n-hexane (manufactured by Wako Pure Chemical: boiling point: 68 ° C.).
Distillation was carried out under atmospheric pressure at a reflux ratio of 50 using a 30-stage Oldershaw type distillation column. As a result, the column top temperature was 4
Equivalent to about 29.5% of the initial weight at a constant temperature of 7.1 ° C 118
g of fraction could be obtained. The fraction which exhibited an azeotropic state at a constant temperature of 47.1 ° C. was analyzed by gas chromatography (GC-14A manufactured by Shimadzu Corporation) to find that HFC-43-10m
The composition was composed of 86.7% by weight of ee and 13.3% by weight of n-hexane.

[0014]

Example 2 A sample bottle (20 ml) was filled with HFC-43-10mee8.
67 g and 1.33 g of n-hexane were taken and mixed at room temperature, and 0.1 g of refrigerating machine oil (Atmos HAB15F: manufactured by Nippon Petroleum) was put therein and shaken by hand at room temperature and stirred. The refrigerator oil was uniformly dissolved in the mixed composition.

[0015]

Example 3 A composition comprising 90% by weight of HFC-43-10mee and 10% by weight of n-hexane was measured in accordance with JIS: K-2265.
The flash point of this composition was significantly higher than that of n-hexane alone.

[0016]

[Comparative Example 1] HFC-43-10mee was placed in a sample bottle (20 ml).
10 g was weighed, and 0.1 g of the same refrigerating machine oil as used in Example 2 was put therein, shaken by hand at room temperature, and allowed to stand. The solubility in fats and oils is HFC-43-1
The azeotropic composition of the present invention is clearly superior to the case of 0mee alone.

[0017]

The composition of the present invention (minimum boiling point: 47.1 ° C.)
As is clear from the examples, the boiling point is close to that of CFC-113 (about 48 ° C.), the conventionally used apparatus can be used as it is, and azeotropic or similar behavior is exhibited, so that liquid management is easy. In addition, since the solubility in fats and oils is higher than that of HFC-43-10mee alone, it is useful for degreasing and washing grease and processing oil used for metal parts as a processing and rust preventive, and for removing flux during semiconductor production.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C23G 5/028 C23G 5/028 H05K 3/26 H05K 3/26

Claims (2)

(57) [Claims] 1. The method according to claim 1, comprising 70 to 99% by weight of 1,1,1,2,3,4,4,5,5,5-decafluoropentane and 30 to 1% by weight of n- hexane. Azeotropic composition. 2. The method of claim 1 wherein said copolymer comprises about 87 % by weight of 1,1,1,2,3,4,4,5,5,5-decafluoropentane and about 13 % by weight of n-hexane. Boiling composition.