Patent GB-1007172-A (GB)
Title: Process for the preparation of organophilic pigments
IPC: C09C3/08
Filed: 1962-06-18
Abstract: Hydrophilic substances selected from (a) oxide, chromate, sulphide, cyanide, antimonate, selenide and vanadate inorganic pigments, (b) azo and phthalocyanine organic pigments, and (c) filling materials, are rendered readily dispersible in organic media by reaction of an aqueous suspension of said substance in the presence of one or more amphoteric oxides, oxide hydroxides or hydroxides of Zn, Al, Pb or Cr with an aqueous solution of an anionic surface active agent having an apolar grouping and recovering resultant precipitates, which may be washed, and which is then dried. Amphoteric substances may be ZnO, Al2O3, AlO(OH), Al(OH)3, Pb(OH)2, and Cr(OH)3. Anionic surface active agents may be ammonium or alkali metal salts of: saturated, unsaturated, and substituted fatty acids containing at least 8 carbon atoms; of polymerized unsaturated fatty acids; or of alkyl, aryl or mixed aryl-alkyl sulphonic, sulphuric, phosphoric or polyphosphoric acids:  e.g. stearic, palmitic, oleic, ricinoleic, caprylic, perlargonic, lauric, cetylsulphonic, cetylnaphthalenesulphonic, cetylphosphoric, or dicetylpyrophosphoric acids, or boiled linseed oil.  To a 2-65% aqueous suspension of the hydrophic substance, 0.1 to 4% by weight, based on the weight of the phydrophilic substance, of the amphoteric substance is added, the mixture is stirred and is allowed to react with a 1-5% by weight aqueous solution of the surface active agent, at 70-80 DEG  C.  The weight of anionic surface active agent is 0.1-15% of that of the hydrophilic substance.  After drying, the substance may be disintegrated.  Examples of substances treated are (a) iron oxide, chromium oxide, bauxite red, titanium dioxide, lead oxide, barium chromate, strontium chromate, zinc chromate, lead chromate, Berlin blue, cadmium sulphide, arsenic sulphide, antimony sulphide, tin sulphide, mercury sulphide, cadmium sulphide selenide, zinc sulphide, cobalt violet [CoO3(PO4)2], Naples yellow (lead antimonate), molybdic red [xPbO.PbCrO4+yPbMoO4+zPbSO4]; (b) Hansa yellow (from m-nitro-p-toluidine and acetyl acetanilide) ("Hansa" is a Trade Mark), permanent red (from o-chloro-p-nitraniline and b -napthol), benzidine yellow (from dichlorobenzidine and acetylaceto-m-xylidine), benzidine orange (from dichlorobenzidine and phenyl methyl pyrazolone), Helio red RMT extra (from m-toluidino-o-sulphonic acid and b -naphthol), Helio bordeaux BL (from a -naphthoylamine and 1-naphthol-5-sulphonic acid), permanent bordeaux FRE (from m-nitro-o-toluidine and b  - oxynaphthoyl - o - toluidine), phthalocyanine blue, or phthalo-cyanine green.ALSO:Hydrophilic substances selected from (a) oxide, chromate, sulphide, cyanide, antimonate, selenide and vanadate inorganic pigments, and (b) filling materials, are rendered readily dispersible in organic media by reaction of an aqueous suspension of said substance in the presence of one or more amphoteric oxides, oxide hydroxides or hydroxides of Zn, Al, Pb or Cr with an aqueous solution of an anionic surface active agent having an apolar grouping and recovering resultant precipitate, which may be washed, and which is then dried.  Amphoteric substances may be ZnO, Al2O3, AlO(OH), Al(OH)3, Pb(OH)2, and Cr(OH)3.  Anionic surface active agents may be ammonium or alkali metal salts of: saturated, unsaturated, and substituted fatty acids containing at least 8 carbon atoms; of polymerized unsaturated fatty acids; or of alkyl, aryl or mixed aryl-alkyl sulphonic, sulphuric, phosphoric or polyphosphoric acids: e.g. stearic, palmitic, oleic, ricinoleic, caprylic, perlargonic, lauric, cetylsulphonic, cetylnaphthalenesulphonic, cetylphosphoric, or dicetylpyrophosphoric acids, or boiled linseed oil.  To a 2-65% aqueous suspension of the hydrophilic substance, 0.1 to 4% by weight, based on the weight of the hydrophilic substance, of the amphoteric substance is added, the mixture is stirred and is allowed to react with a 1-5% by weight aqueous solution of the surface active agent, at 70-80 DEG  C.  The weight of anionic surface active agent is 0.1-15% of that of the hydrophilic substance. After drying, the substance may be disintegrated. Examples of substances treated are (a) iron oxide, chromium oxide, bauxite red, titanium dioxide, lead oxide, barium chromate, strontium chromate, zinc chromate, lead chromate, Berlin blue, cadmium sulphide, arsenic sulphide, antimony sulphide, tin sulphide, mercury sulphide, cadmium sulphide selenide, zinc sulphide, cobalt violet [CoO3(PO4)2] Naples yellow (lead antimonate), molybdic red [xPbO.PbCrO4 + yPbMoO4 + zPbSO4].