Discolored black ink and preparation method thereof

Abstract

The invention provides discolored black ink and a preparation method thereof. The black ink comprises, by weight, 0.8-0.85% of a red dye, 2.5-3.0% of a green dye, 3.0-3.5% of a thickener, 1.0-1.5% of a surfactant, 0.15-0.20% of a preservative and the balance of distilled water. The red dye is acid fuchsin or basic fuchsin. The green dye is an acidic green dye, a basic green dye or a brilliant green dye. The preparation method is simple, utilizes raw materials having wide sources and realizes a low cost. The black ink is non-toxic, has no pungent smell and can fade when contacting with a reductive material. The paper with the ink can be recycled.

Description

technical field [0001] The invention relates to the fields of stationery and printing, in particular to ink, in particular to a fadeable black ink and a preparation method thereof. Background technique [0002] The color material of traditional black ink is mostly carbon black, a single black pigment or dye. Although it has good stability, smooth writing and affordable price, the handwriting of these inks cannot be faded. Recycling of written paper is a big environmental protection issue. . The development of dye-based black ink is conducive to enriching the application field and market demand of black ink. Using the principle of dye complementary color, CN 1415674A, CN1415674A and CN104046128A disclose different types of ternary color complementary black dye ink compositions respectively, which promotes the development of dye-based black ink. The marketization process of black ink. However, the dye-based black inks involved in these technologies are all permanent colorant...

AI Technical Summary

Problems solved by technology

However, the dye-based black inks involved in these technologies are all permanent colorant complexes, which cannot realize the fading function, and it is difficult to recycle the paper after writing or printing