Studies on the Dyeing of Chitin and Chitosan with pre-metallised Dyes at Neutral pH

• Authors: Simon Mazengarb , George AF Roberts , Frances A. Wood
• Languages of publication: EN

Abstracts

EN

Both 1:1 pre-metallised acid dyes and pre-coppered direct dyes, but not 1:2 pre-metallised acid dyes, have been shown to readily dye chitin and chitosan from neutral dyebaths. With the 1:1 pre-metallised acid dyes the addition of neutral electrolyte increases the uptake of dye, indicating that electrostatic forces of attraction are not involved in the adsorption process. A mechanism of dyeing is proposed involving complex formation between the metal ion of the pre-metallised dye and the amine groups of the substrate. The wet fastness properties of the 1:1 pre-metallised acid dyeings carried out at neutral pH are at least equal to, and in many cases greater than, those obtained by the conventional dyeing process at pH values of 4.5 - 5. In the case of precoppered direct dyes a rigorous washing-off process is required in order to remove dye adsorbed on the substrate, but not complexed with the amine groups, if the maximum wet fastness is to be achieved.

Keywords

EN

chitin; chitosan; pre-metallised dyes; neutral dyeing

• Publisher: Sieć Badawcza Łukasiewicz - Polskie Towarzystwo Chitynowe
• Journal: Progress on Chemistry and Application of Chitin and its Derivatives
• Year: 2010
• Volume: 15
• Pages: 87 - 96

Contributors

author

Simon Mazengarb

• Department of Textiles & Fashion, Nottingham Trent University

author

George AF Roberts

• Biomedical Materials Engineering Unit, University of Nottingham

author

Frances A. Wood

• Department of Textiles & Fashion, Nottingham Trent University

References

• Allen R. L. M.; Colour Chemistry, Nelson, 1971 pp. 46-52.
• Roberts G. A. F., Wood F. A.; Dyeing chitin and chitosan under neutral conditions, Chitin and chitosan: Chitin and chitosan in life sciences (T. Uragami, K. Kurita and T. Fukamizo eds.), Tokyo, 2001, pp. 150-151.
• Mazengarb S., Roberts G. A. F.; Studies on the diffusion of direct dyes in chitosan film, Progress Chem. Appl. Chitin & Derivatives, 2009, 14, in press.
• Peters R. H.; Kinetics of dyeing, Diffusion in polymers (J. Crank and G.S. Parks (eds.) 1968, pp. 315-372.

• Document Type: article