Patent GB-774079-A (GB)
Title: Improvements in pigment dispersions in water
IPC: D06P1/44
Filed: 1953-05-01
Abstract: An aqueous dispersion of a hydrophobic organic pigment or of carbon black is made by forming an aqueous slurry of the pigment in the presence of a water soluble fatty alcohol sulphate salt or a hydroabietyl sulphate salt, and subjecting the slurry to mechanical treatment to deflocculate the pigment, the said sulphate salts being present in the proportions of from 9 to 40 parts by weight per 100 parts of pigment, or, if certain auxiliary agents are present, of 4 1/2 to 40 parts per 100 parts of pigment.  The water soluble salts may be ammonium, sodium or triethanolamine salts.  The auxiliary agents may be sodium lignin sulphonate, partially desulphonated sodium lignin sulphonate, calcium lignin sulphonate, sodium salts of formaldehydealkyl naphthalene sulphonic acid condensation products, condensed aryl sulphonates, polyethylene oxide condensation products with aryl sulphonates and alkyl substituted naphthalene sulphonates in which the alkyl group contains from 3 to 5 carbon atoms, and are used in the proportion of at least 1/2 per cent based on the pigment content.  Protective colloids, e.g. from 1/2 to 50 parts by weight of casein, or from 1 to 10 parts of methyl cellulose per 100 parts of pigment, may also be present.  The pigments include copper or copper-tin phthalocyanines insoluble azo pigments or vat pigments of indigoid type (including thioindigo derivatives) or of anthraquinone type, and at least part of the pigment, and of the water may initially be present in the form of a press-cake.  The pigment dispersions may be used to form textile decorating colour concentrates in conjunction with emulsified resinous esters of a polyunsaturated fatty oil acid formed with a polyhydric alkoxy derivative of a polynuclear polyhydric phenol, as described in Specification 774,078.ALSO:An aqueous dispersion of a hydrophobic organic pigment or of carbon black pigment is made by forming an aqueous slurry of the pigment in the presence of a water soluble fatty alcohol sulphate salt or a hydroabietyl sulphate salt, and subjecting the slurry to mechanical treatment to deflocculate the pigment, the said sulphate salts being present in the proportions of from 9 to 40 parts by weight per 100 parts of pigment, or, if certain auxiliary agents are present, from 4 1/2 to 40 parts per 100 parts of pigment.  The water soluble salts may be ammonium, sodium or triethanolamine salts.  The auxiliary agents may be sodium lignin sulphonate, partially desulphonated sodium liguin sulphonate, calcium lignin sulphonate sodium salts of formaldehyde-alkyl naphthalene sulphonic acid condensation products, condensed aryl sulphonates, polyethylene oxide condensation products with aryl sulphonates and alkyl substituted naphthalene sulphonates in which the alkyl group contains from 3 to 5 carbon atoms, and are used in proportions of at least 1/2 per cent based on the pigment content.  Protective colloids, e.g. from 1/2 to 50 parts by weight of casein, or from 1 to 10 parts of methyl cellulose per 100 parts of pigment, may also be present.  The pigment, an insoluble azo pigment, cyanine pigment, an insoluble azo pigment, a vat pigment or carbon black, and at least part of the water, may initially be present together in the form of a press-cake.  The pigment dispersions may be used to form textile decorating colour concentrates in conjunction with emulsified resinous esters of a polyunsaturated fatty oil acid formed with a polyhydric alkoxy derivative of a polynuclear polyhydric phenol, as described in Specification 774,078 [Group IV(c)]