Syntheses and properties of some deeply coloured dichroic anthraquinone dyes

The syntheses of some aryl-1,5-diamino-4,8-dihydroxyanthraquinone dyes is described and their properties are discussed on the basis of colour-structure relationships, dichroism and their solubility in liquid crystals. The PPP-MO calculated results agreed well with the observed λ max values. 2-Aryl-1...

Full description

Saved in:
Bibliographic Details
Published in:Dyes and pigments 1989, Vol.11 (2), p.81-91
Main Authors: Yasui, Shigeo, Matsuoka, Masaru, Kitao, Teijiro
Format: Article
Language:English
Subjects:
Applied sciences
Chemical industry and chemicals
Dyes, pigments
Exact sciences and technology
Industrial chemicals
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The syntheses of some aryl-1,5-diamino-4,8-dihydroxyanthraquinone dyes is described and their properties are discussed on the basis of colour-structure relationships, dichroism and their solubility in liquid crystals. The PPP-MO calculated results agreed well with the observed λ max values. 2-Aryl-1,5-dihydroxy-4-arylamino-8-aminoanthraquinones had better dichroism and improved solubility compared with their 8-arylamino-4-amino analogues. 2-Aryl-1,5-dihydroxy-4,8-bis(arylamino)anthraquinones also had satisfactory dichroism and solubility. It was found that the presence of 2-aryl- and 4-aryl-amino groups in deeply coloured anthraquinone dyes resulted in a favourable orientation of the dye molecules in liquid crystals, producing good dichroism and improved solubility, and such compounds can be used practically as deep-blue dichroic dyes.
ISSN:0143-7208
1873-3743
DOI:10.1016/0143-7208(89)85028-4