GB920851A - Chromono-xanthone and thiochromono-thioxanthone pigments - Google Patents

Abstract

A red wallpaper colour is made by mixing with a glue solution the precipitate obtained by adding barium chloride solution to a suspension made by adding sodium carbonate solution and a pigment of the formula:- <FORM:0920851/III/1> where X is oxygen, to a suspension of heavy spar in aluminum sulphate solution. Printing inks contain the pigment of the above formula where X is oxygen or sulphur and the 4- and 8-positions may also be substituted by chlorine, having a particle size between 0,01 and 0,5m . In examples (1) a pigment of the above formula is ground with aluminium hydroxide and linseed oil varnish, and (7) an aqueous paste of a pigment of the above formula is mixed with heavy spar, aluminium sulphate and sodium carbonate solution, barium chloride solution is added and the precipitated product is mixed with a glue solution.ALSO:Nitrocellulose, acetyl cellulose, viscose, linear polyesters and polyamides, polyester resins, phenoplasts, aminoplasts, polyurethane lacquers, polyolefines such as polyethylene, polystyrene, polyvinyl chloride, polyacrylonitrile and rubber are coloured red with a pigment of the general formula:- <FORM:0920851/IV(a)/1> where X is oxygen or sulphur and 4- and 8-positions may also be occupied by chlorine, having a particle size between 0,01 and 0,5m . In examples a pigment of the above formula is ground or mixed with, (8), a nitrocellulose lacquer containing pyroxylin, dibutyl phthalate, benzyl butyl phthalate, a synthetic resin obtained from cyclohexanone by treatment with sodium hydroxide, butyl acetate, methyl acetate and toluene and optionally, inorganic pigments and fillers; (2), a stoving lacquer of a coconut oil alkyd resin, urea-formaldehyde resin, xylene and butanol; (3), an unsaturated polyester resin and stirred with monostyrene, cyclohexanone peroxide, dibutyl phthalate, cobalt naphthenate and silicone oil solution in xylene; (4), polyvinyl chloride, di-iso-octyl phthalate and titanium dioxide (rutile); (5), polystyrene granulate; and (6) pale crepe, sulphur, stearic acid, 2-mercaptobenzthiazole, hexamethylene tetramine, zinc oxide, chalk and titanium dioxide (anatase) followed by vulcanization.ALSO:The invention comprises pigments of the formulae:- <FORM:0920851/IV(a)/1> <FORM:0920851/IV(a)/2> and <FORM:0920851/IV(a)/3> and pigments of the general formula:- <FORM:0920851/IV(a)/4> where X is oxygen or sulphur and in which the 4- and 8-positions may also be occupied by chlorine, having a particle size between 0,01 and 0,5m . The pigments are made by reacting 2:5 - dichlor - 1:4 - benzoquinone - 3:6 - dicarboxylic acid esters with 4-chloro- or 2:4-dichlorophenol or -thiophenol, conversion of the diaryl ethers or thioethers by reduction into the dihydroxy compounds followed by saponification and ring closure. The pigments may be converted to the finely-divided form by acidpasting or grinding. The pigments colour a wide variety of materials in red shades.