| 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 R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP> and R<SP>4</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. |
