Mordant Dyes

Mordant Dyes

 

synthetic dyes that are used with auxiliary substances called mordants. Specific mordant dyes are used for cotton and wool. The mordant applied in the dyeing of wool is Na2Cr2O7. During the dyeing process, hexavalent chromium becomes trivalent and combines with the dye and the wool to form a stable complex compound. Hence the name chrome dyes. Mordant dyes are rarely used for cotton because of insufficient dye stability.

Mordant dyes are classified according to chemical structure as azo dyes and anthraquinone dyes, even though the latter are often used without a mordant. The ability of mordant dyes to form complexes with trivalent chromium is dependent on the presence of specific atomic groups in their composition, for example, two OH groups, or OH and NH2, or COOH and OH in ortho positions relative to the azo group. One example of a mordant dye is chrome blue 2K:

In wool dyeing, mordant dyes impart color with exceptional fastness and are widely used in those cases where bright colors are not necessary.

REFERENCE

Chekalin, M. A., B. V. Passet, and B. A. Ioffe. Tekhnologiia organiches-kikh krasitelei i promezhulochnykh produktov. Leningrad, 1972.

M. A. CHEKALIN

References in periodicals archive ?
Among the topics are the structure of wool, the role of auxiliaries in dyeing wool and other keratin fibers, wool-dyeing machinery, dyeing wool with acid and mordant dyes, dying wool blends, and the coloration of human hair.
Table 60: US Exports of Acid And Mordant Dyes (2008 &
Table 61: US Imports of Acid And Mordant Dyes (2008 &
Table 84: Canadian Exports of Acid And Mordant Dyes (2008 &
Acid and Mordant Dyes and Preparations Based Thereon: European Union Market Outlook 2010 and Forecast till 2015 (http://marketpublishers.
Table 61: US Imports of Acid And Mordant Dyes (2008 &2009): Imports Ranked by Value in US$ Thousand by SourceCountry - India, China, Switzerland, Mexico, Thailand,Indonesia, Germany, Ireland, Japan, UK and Others (includescorresponding Graph/Chart) III-8
Table 85: Canadian Imports of Acid And Mordant Dyes (2008 &2009): Percentage Breakdown of Imports Ranked by Value bySource Country - US, Germany, China, Mexico, India,Malaysia, France, Switzerland, Brazil, Japan and Others (includes corresponding Graph/Chart) III-27
Table 63: US Exports of Acid And Mordant Dyes (2008 &
Table 64: US Imports of Acid And Mordant Dyes (2008 &
Table 87: Canadian Exports of Acid And Mordant Dyes (20