Documents

[I] Introduction

Description
chem
Categories
Published
of 23
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  Natural Dyes -Natural yellow dyes, based on flavones, chalcones and polyenes, are weakly colored, unstable and fades by light. -However, the anthraquinone and indigo   chromogens , respectively found in the natural red and blue dyes  are stable and form the basis of many of the modern synthetic dyes.  OOOOO NNOHHO ROOC( CH = CH )  n COOR   n = 7 - 9 ; R = H , Me Polyenes Flavones ( 2-Phenylchromones) Chalcones (benzalacetophenone)  anthraquinone indigo  Classification of Dyes ã Chemical Classification  : ã Nitro dyes, Nitroso dyes ã  Azo dyes ã Diphenylmethane dyes, Triphenylmethane dyes ã Xanthene dyes ã  Anthraquinone dyes ã  Acridine dyes ã Indigoid dyes ã Phthalocyanine dyes ã Polymethine dyes ã Sulphur dyes    Usage Classification of Dyes   Method of Application   Substrate   Chemical Type   Class   From neutral or acidic dyebath Nylon  –  woolSilk  Azo  – anthraquinone triphienylmethane Acid(anionic)From acidic dyebath Paper  –  polyester Cyanine  –  azo - azine  – acridine - oxazine Basic(cationic) From neutral or slightly alkaline containing additional electrolyte Cotton - leather  Azo - phthalocyanine Direct (anionic) Applied in conjunction with Cr salts Wool  –  leather  –  anodized Al  Azo  –  anthraquinone Mordant Water-insoluble dyes solubilized by reduction with sodium hydrogen sulfite, introduced into the fiber and then reoxidised Wool  –  cotton  –  rayon Indigo - anthraquinone Vat dyes,dispersed on synthetic fibres by heat&pressure before application . Mainly used in photographyPolymethine, phthalocyanine Nitro dyesDisperseproduced in situcellulose Azo Azoic (Ingrain)

EIP Guide

Jul 23, 2017
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks