Claims
- 1. A hexagonal shaped particle of zinc pyrithione characterized by sharp particle corners and straight particle edges, said particle being produced by reacting pyrithione or a water-soluble salt of pyrithione and a water-soluble polyvalent metal salt in an aqueous medium and in the presence of a dispersing additive to produce particles of pyrithione salts, wherein sonic energy is applied to said aqueous medium during said reacting step to produce a suspension of non-agglomerated pyrithione salt particles, said non-agglomerated pyrithione salt particles having a hexagonal shape and median size of from about 0.1 to about 50 micros wherein said dispersing additive is carboxymethyl cellulose.
- 2. An antidandruff shampoo comprising a suspension, emulsion, or dispersion of non-agglomerated particles of pyrithione salts made by reacting pyrithione or a water-soluble salt of pyrithione and a water-soluble polyvalent metal salt in an aqueous medium and in the presence of a dispersing additive to produce particles of pyrithione salts, wherein sonic energy is applied to said aqueous medium during said reacting step to produce said suspension emulsion or dispersion of non-agglomerated pyrithione salt particles, said non-agglomerated pyrithione salt particles having a median size of from about 0.1 to about 50 microns wherein said dispersing additive is carboxymethyl cellulose.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a division of U.S. patent application Ser. No. 09/256,969, filed Feb. 23, 1999 now U.S. Pat. No. 6,465,015, the disclosure of which application is incorporated by reference in its entirety herein.
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