PIGMENT AND A METHOD OF ITS PRODUCING Russian patent published in 1998 - IPC

FIELD: inorganic pigments. SUBSTANCE: deposits obtained after electrochemical treatment of galvanic production sewage containing (as measured for oxides in dry product), wt.-%: iron oxides 75.0-97.3; nickel (II) oxide 0.55-9.3; chrome (III) oxide 0.13-13.0; calcium oxide 0.01-2.49; zinc oxide 0.01-2.0; cadmium oxide 0.01-0.2 (moisture is 75-90%) and products of reagent precipitation of these waste with calcium hydroxide containing (as measured for oxides in dry product), wt.-%: iron oxides 15.0-22.0; chrome (III) oxide 1.5-12.0; nickel (II) oxide 0.01-2.0; aluminium oxide 0.5-15.2; silicon oxide 0.02-8.0; calcium oxide 28.5-64.0; copper oxide 0.5-14.0. zinc oxide 1.0-5.6; cadmium oxide 0.01-0.5; lead oxide 0.01-0.4; magnesium oxide 2.0-7.25 (moisture is 60-80%) are mixed at mass ratio: deposits obtained after electrochemical treatment of galvanic production sewage 25-50, products of reagent precipitation of waste with calcium hydroxide 70.5-49.5 and reducing agent - finely divided iron or aluminium is added at amount 0.5-4.5 wt. -%, stirred thoroughly, dried at 80-110 C to residual moisture 20-30 wt. -% and calcined at 600-800 C for 30-120 min followed by grinding of the obtained pigment particles to size 10 mcm, not above. Pigments show colors from beige to chocolate-brown. Properties: covering power is 10-15 g//m²,, oil absorption is 32-44 g/100 g pigment. Pigments can be used for staining plastics, rubber, natural and artificial leather, production of paint and varnish materials, for building ceramics decorating. EFFECT: improved quality and properties of pigments. 2 cl, 1 tbl