High-boiling hydrochlorofluorocarbon solvent blends
AssigneeE. I. Du Pont de Nemours and Company
InventorsDavid S. Lermond, Kenneth T. Dishart, Abid N. Merchant
Life of this patent
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Abstract
A high-boiling hydrochlorofluorofluorocarbon (HCFC) solvent comprising a blend of for every 100 parts by weight of a hydrochlorofluorocarbon (e.g., 1,1,1-trifluorodichloroethane or 1,1-dichloro-1-fluoroethane) from about 25 to about 400 parts by weight of a selected organic solvent (e.g., dipropylene glycol monomethyl ether, dipropylene glycol monomethyl ether acetate, or mixture of dimethyladipate, dimethylglutarate, and dimethylsuccinate). Such solvents are useful in liquid/vapor phase cleaning applications even at elevated temperatures above the boiling temperature predicted by Raoult's law.
Claims28
A composition comprising a liquid blend of a liquid cosolvent and a liquid hydrogen-containing chlorofluorocarbon which exhibits an affinity for said cosolvent, wherein for every 100 parts by weight of said hydrogen-containing chlorofluorocarbon there is present from about 25 parts by weight to about 400 parts by weight of said cosolvent selected from the group consisting of:
- (a) C.sub.1 to C.sub.6 mono or di alkyl ethers of dipropylene glycol;
- (b) C.sub.1 to C.sub.6 esters of dipropylene glycol mono alkyl ethers;
- (c) C.sub.1 to C.sub.6 diesters of C.sub.4 to C.sub.6 organic dicarboxylic acids;
- and
- (e) mixtures thereof.
A high-boiling cleaning solvent comprising:
- (a) from about 80 to about 20 weight percent of a liquid phase organic solvent selected from the group consisting of;
- (i) dipropylene glycol mono and di alkyl ethers,
- (ii) esters of a dipropylene glycol mono alkyl ether,
- (iii) C.sub.1 -C.sub.6 diesters of C.sub.4 to C.sub.6 dicarboxylic acids, and
- (iv) mixtures thereof;
- and
- (b) from about 20 to about 80 weight percent of a hydrogen-containing chlorofluorocarbon to produce a blend wherein said liquid phase organic solvent and hydrogen-containing chlorofluorocarbon mixture boils at a temperature above the boiling temperature predicted by Raoult's law.
A cleaning solvent composition comprising:
- (a) from about 80 to about 20 weight percent of a liquid cosolvent selected from the group consisting of:
- (i) a dipropylene glycol monoalkyl ether,
- (ii) an ester of a dipropylene monoalkyl ether, and
- (iii) one or more C.sub.1 to C.sub.6 diesters of C.sub.4 to C.sub.6 dicarboxylic acids;
- and
- (b) from about 20 to about 80 weight percent of a hydrogen-containing chlorofluoroethane, wherein said hydrogen-containing chlorofluoroethane exhibits an affinity for said liquid cosolvent.
A method of cleaning a dirty article comprising the steps of:
- (a) immersing said dirty article in a high-boiling cleaning solvent comprising, a liquid cosolvent and an effective amount of a liquid hydrogen-containing chlorofluorocarbon which exhibits an affinity for said cosolvent such as to produce a blend that boils at a temperature above the boiling temperature predicted by Raoult's law, at a temperature above the boiling temperature predicted by Raoult's law for said blend for a sufficient time to clean said article;
- and
- (b) recovering a clean article.
Dependencies are inferred from the claim text.