摘要 |
<p>PV. 30734 PIGMENT DISPERSANTS, PIGMENT CONCENTRATES AND THEIR USE ? AQUEOUS COATING COMPOSITIONS AND PRINTING ?. A polymeric water-dispersible pigment dispersant is prepared by interacting at a temperature not greater than 150.degree.C. (a) a carboxylic acid of structure (R1)(R2)(R3) C.COOH wherein R1 /A R2 =CnH2nX, the same or different and wherein n = 1-8 and X is a group reactive with an isocyanate group, and wherein R3 = C1-8 alkyl, (b) An aliphatic polyol, and (c) a di- or tri-isocyanate. Preferably the dispersant comprises a C8-20 aliphatic hydrocarbon moiety. The dispersant, which is used in the preparations of pigment concentrates, pigmented aqueous coating compositions and printing inks, is of improved hydrolytic stability and minimises pigment leaching under humid conditions.</p> |