Re: Dye for support fabrics

["Mary W. Ballard" <BallardM@xxxxxxxxxxxx>]

Erikka Wessel & all--It is sometimes difficult to compare dyestuffs when tradenames of a particular company are used, since the trade names in North America may be different from those in Europe or the Far East. Most recently, the dye products divisions of companies have merged or been sold. Lanasets are acid dyes for wool or silk, Irgalans are "neutral (premetalized)" acid dyes" and Lanasols are acid or fiber reactive dyes. Acid dyes are named this way because of the acid assist needed to promote the dyeing of the fiber: mostly used on fibers composed of proteins (amino acids). The "neutral acid dyes" require only a mild acid assist. The fiber reactives bond covalently to cellulose with the help of mild alkalis. The durability of the dye will depend upon the application method, the fiber substrate, and the particular chemical composition of the dye--not just how it attaches to the fiber but how well the color lasts to light. Sometimes the choice of dyestuff has also depended !
upon what hues are available: the bright colors of fiber reactives may have to be toned down by mixtures while the dull shades of the "neutral premetalized" may be better for some matching. Fiber reactives as a class tend to be more washfast than direct dyes ("substantives") since they are bonded to the fiber covalently, not just by proximity. This is a long way of saying, what is most appropriate for you and your work may depend on what your support fabrics or yarns are meant to do. There are excellent books and papers on dyeing in the literature--and manufacturers can be very helpful. If you have the support and help of a manufacturer, you are quite fortunate! I am sure that other colleagues will be able to give you additional ideas. Mary Ballard

>>> erw@xxxxxxxxxxxxxxxxxxxx 03/01/02 08:39AM >>>
Dear Colleges,