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Color changing compositions for highlighters

  • US 5,492,558 A
  • Filed: 10/03/1994
  • Issued: 02/20/1996
  • Est. Priority Date: 07/31/1992
  • Status: Expired due to Term
First Claim
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1. A multiple coloring composition system comprising:

  • (a) an aqueous undercolor coloring composition comprising a undercolor dye whose coloring ability is destroyed in the presence of a pH of about 10 or greater, in the presence of a reducing agent, or a combination thereof, and a compatible surfactant in an amount sufficient to increase the stability of said coloring composition; and

    (b) an aqueous overcolor coloring composition comprising an overcolor dye capable of maintaining its characteristic color in the presence of a pH of about 10 or greater, an effective amount of base sufficient to yield a pH of the aqueous overcolor coloring composition of about 10 or greater, and a compatible surfactant in an amount sufficient to increase the capillary flow of said aqueous overcolor coloring composition.

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