method for preparing a preparation used as coolant.and the application of this preparation in locating leaks in a warmteoverdrachtsysteem of dampcompressie type.

摘要

1392978 Colouring refrigerant compositions E I DU PONT DE NEMOURS & CO 22 Nov 1972 [22 Nov 1971] 53877/72 Heading C4X A fluorocarbon refrigerant and/or a refrigeration oil is coloured for leak detection by at least one anthraquinone dye wherein 2 or 3 of RSP1/SP, RSP2/SP, RSP3/SP and RSP4/SP are H, and the remaining 1 or 2 is or are an anilino group substituted by 1-3 saturated alkyl groups having a total of 4-24 carbon atoms. Preferred dyes are 1-(4-butyl-anilino) anthraquinone and 1-(4- dodecylanilino) anthraquinone. The fluorocarbon may be one of a number of chloro- or bromo-fluoroalkanes or an azeotropic mixture thereof, and the oil may be a naphthenic, paraffinic, alkylated benzene or polyalkyl silicate oil. An inert co-solvent for the dye and refrigeration liquid, e.g. xylene, may be used to aid solution.