OPTICAL BLEACHING AGENTS FOR HIGH-QUALITY JET PRINTING Russian patent published in 2017 - IPC C07D251/68 C07D403/12 C11D3/42 D21H21/30 D06P5/30 

FIELD: printing industry.

SUBSTANCE: invention relates to an optical bleaching agent comprising of a mixture of compounds of the formulas

and

wherein R is hydrogen or methyl; Y is an amino acid that is derived from aspartic acid, glutamic acid or iminodiacetic acid and from which the hydrogen atom of the amino group is removed; and M is an alkali metal cation. The invention also relates to an optical bleaching agent comprising a compound of formula (4), to a process for preparing an optical bleaching agent, to a compound of formula (4), to a composition for bleaching paper surface, and to paper optically bleached with an optical bleaching agent.

EFFECT: new optical bleaching agents are obtained, providing a bleaching effect when applied to the paper surface.

14 cl, 1 tbl, 9 ex