Patent No. EP2933297 (titled "Pigment Dispersant, Production Method For Pigment Dispersant, And Pigment Dispersion Liquid") was filed by Dainichiseika Color & Chemicals MFG on Nov 26, 2013. The application was issued on May 10, 2017.
A pigment dispersant for achieving high dispersion stability and fluidity in oil-based inks, paints, and coatings. The dispersant is a graft copolymer formed through living radical polymerization of specific monomers, comprising a main chain with an acidic or basic group and side chains derived from macromonomers with molecular weights of 500-5000. The polymerization is controlled to achieve a main chain molecular weight of 1700-4250 and a side chain proportion of 50-90 mass%. The dispersant enables high-performance pigment dispersion in a wide range of applications.

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