silk-cotton where silk is a weft thread and cotton is a warp thread...
  • I have a piece of fabric (baby-carrying wrap) that is 5m long 30" wide and it has a cross thread that is raw silk and a weft thread that is cotton. My hope is to dye the silk thread one color and the cotton thread a different color so there is a decent noticeable contrast between the two. Like the silk thread orange and the cotton thread black. Is this impossible? Or vice versa, the cotton a light color and the silk a dark color.

    If I use my Procion MX dyes should I FIRST do the soda ash fiber reactive dye and then do a vinegar dye job? I have read somewhere that a soda ash bath on a vinegar-acid dyed silk will cause discharging of the color. I tested it with some raw silk scraps (not the actual fabric i plan to use for this project) and my food-colored silk scraps dyed with vinegar seemed to discharge, but not 100%.

    If the above is sort of theoretically impossible, I am fine with doing just an acid dye job so that the silk takes color and the cotton remains undyed. Will using vinegar with Procion MX (dharma dye) really work??? I HATE using food coloring/koolaid to dye (it stains darn near everything and procion is so much easier to clean up!) Is citric acid a better acidic solution than vinegar for silk? is heat imperative for the vat dying? salt a good idea? Sorry for all the questions but I am feeling "fear" of dying this piece and ruining the entire thing :( :( so answers to anything will help me!

    I really would like some feedback because this is a quite expensive piece of fabric and I'd love to get the results I dream of!
  • Hi,
    Some of the MX colors such as chocolate brown give a different color on silk than on cotton. plant based fibers come out brown, protine based come out rose colored. That could be one way of acheiving a different color on each fiber type.
  • Premixed colors of Procion MX dyes will often give different colors on silk than on cotton, when used with soda ash. There is no need to do an additional acid-fixed step, since Procion MX dyes work extremely well on silk when used with soda ash. However, if you use a pure unmixed single-hue Procion MX dye, you will get the same hue on silk as on cotton or rayon. See Which Procion MX colors are pure, and which mixtures?.

    Another way to get contrasting colors on the silk and cotton threads is by dyeing with an acid dye that colors only the silk, in addition to either a fiber reactive dye (such as Procion MX) or a direct dye , both of which will color both cotton and silk.

    There's a very expensive product called AlterEgo dye, made by the H. Dupont company, which combines acid dyes, direct dyes, and a chemical reserving agent that prevents the direct dye from coloring the silk, all in one dyebath. The results will not be as colorfast as soda-ash-fixed Procion MX dye, however.

    Here's a link to a much more detailed discussion on how to dye silk and cotton two different colors: Dyeing silk/rayon blends two different colors.