Patents Assigned to 501 Sakata Inkusu Kabushikikaisha
  • Patent number: 5000792
    Abstract: A pigment dispersing agent comprising the reaction product of a polyester having a free carboxyl group, of which the acid value is in the range of from 10 to 60, with an amine compound of the formula: ##STR1## wherein R.sub.1 and R.sub.2 are alkylene radicals which can be the same or different, each containing from 2 to 6 carbon atoms, and R.sub.3 is a radical of the formula CH.sub.3 -- or C.sub.2 H.sub.5 --, wherein said reaction being conducted in the range of from 0.8 to 1.0 of equivalent molar ratio of the amino groups having active hydrogen of said amine compound to the free carboxyl groups of said polyester.Application of the dispersing agent to nonaqueous paint or printing inks enables pigments to be dispersed in the vehicle at higher concentrations with low viscosity than in the prior art, and the dispersions thus obtained exhibit high coloring power and excellent storage stability.
    Type: Grant
    Filed: June 2, 1989
    Date of Patent: March 19, 1991
    Assignee: 501 Sakata Inkusu Kabushikikaisha
    Inventors: Hiroshi Ohta, Tsutomu Matsukawa, Atsushi Nakada