| abstract |
A multiple coloring composition system is disclosed whose coloring effect is changed upon treatment with a second coloring composition, once the second coloring composition has been deposited over the undercolor coloring composition. The multiple ink system comprises: (a) an undercolor aqueous coloring composition comprising an undercolor dye whose coloring ability is destroyed in the presence of a pH of about 10 or greater and/or by a reducing agent; and (b) an overcolor aqueous coloring composition comprising a colorant capable of maintaining its characteristic color in the presence of a pH of about 10 or greater and/or a reducing agent, a base in an amount sufficient to yield a pH of the overcolor composition of about 10 or greater, and/or a reducing agent. |