Pigmented water-base ink composition for writing utensil

Abstract

Abstract PURPOSE:To provide a water-base ink which can retain a stable pigment-dispersibility and gives characters having satisfactory water resistance after writing, consisting of a pigment, a water-soluble amine salt or ammonium salt of a specified copolymer and (thio)urea or its derivative. CONSTITUTION:In a pigmented water-base ink for writing utensils consisting of a pigment, a dispersant, an antidrying agent and an aq. medium, said dispersant is a water-soluble amine salt or ammonium salt of a copolymer composed of less than 50mol% of acrylic or methacrylic acid, and said agent is urea, thiourea or a derivative thereof. The anti-drying agent is used in an amount of 0.5-50pts.wt., pref. 2.5-40pts.wt. per 100pts.wt. pigmented water-base ink. The proportion of the water-soluble monomer in said copolymer as a dispersant is 5-50mol% based on the total amount of monomers to be used. When the amount exceeds 50mol%, water resistance of characters is unsatisfactory, while when the amount is less than 5mol%, the copolymer has no effect as a dispersant.

Inventors

• 👤 Yukito Shoji
• 👤 庄司　幸人

Bibliographic Details