Name: Grace
Message: Dear Paula, first i love your site, it has helped me tremendously! I am a beginning silk painter usion procion mx dyes. I know there are color shifts from cotton to silk using procion.
1. I am desperate for Navy or very dark blue on silk, is this impossible to achieve with procion mx? If not , have a recipe?

Actually, it is a misconception that color changes, for a given dye color, from cotton to silk. If you use a single dye, not pre-mixed with another dye, the color is the same on any fiber. The problem occurs only when you purchase pre-mixed dye colors.

The reason why dye mixtures come out different colors on different fibers is that each dye molecule type has a slightly different dye chemistry than every other one. One dye will strike more quickly than another on silk than on cotton, or vice versa, or have a slightly different pH optimum (the ideal amount of soda ash or acid to use). If, say, you have a blue that is a mixture of turquoise (Procion type turquoise MX-G) and fuchsia (Procion type red MX-8B), it will seem that you have a slightly larger proportion of the red on one fiber, and a slightly larger proportion of blue on another fiber.

When going from one fiber type to another, if you wish to obtain consistent results, you must avoid all pre-mixed colors like the plague, and stick only to pure, unmixed, single-color dyes. I have a listing of pure unmixed Procion MX type (dichlorotriazine) dyes on my web site. This chart includes the catalog names and colors for several of the most popular suppliers; several other dye suppliers use the same names, as well.

You are in luck, since what you want is a very dark blue. This is one of the easiest of all colors to find in pure form. There are four different available navies among the dichlorotriazine (Procion MX type) dyes. Most dye suppliers carry blue MX-2G, or Colour Index reactive blue number 109; Dharma calls it cobalt blue, although it is much greener than a true cobalt blue, while ProChem calls it mixing blue. ProChem also carries another navy, blue MX-4RD, or reactive blue number 168, which is quite nice. I have purchased navy MX-G, or reactive blue #9, directly from Standard Dyes. They now sell a great deal of dye through Rupert Gibbon and Spider, which will ship mail-order for quantities over 8 ounces per color if you order by telephone, but they confuse matters by also selling what they call "blue #9 red shade", which is blue #9 with some red MX-5B added to it; you're trying to avoid such mixed colors. You can also get a lovely dark blue, less greenish in color, by using large quantities of blue MX-R, or reactive blue #4; while Dharma lists this as "sky blue", it's a very nice darker blue if you use enough of it.

2. Does anyone have a chart that shows the listing of color shift changes between using procion mx on cotton vs silk?

Such a chart would be impossible to create, because any shift varies dramatically depending on the exact dye mixture that your dye supplier creates. Each dye seller that sells mixed dyes sells their own proprietary mixtures, plus just a few that are pre-mixed by the manufacturers. It is best to simply avoid all pre-mixed colors, and mix your own, by trial and error. If you find that blue MX-2G is a little too green, add a bit of red MX-5B, but NOT the same relative amount that you would add for the identical shade when dyeing cotton.

3. How can I remove by a spray technique, dyed procion mx on silk without using bleach? I want to remove to add texture than overdye. I just destroyed a piece with a 50% bleach solution. Any hints?

Chlorine bleach is extraordinarily destructive to animal fibers. (It is also destructive to people, and I believe would not be permitted for sale to consumers if it were a new product introduced for the first time to the market today.) It is often possible (depending on the dye) to discharge ("bleach") animal fibers such as silk with the use of sodium hydrosulfate, commonly available as Rit brand Color Remover. Other products that can be used for this purpose on silk include Jacquard discharge paste and ProChem's Thiox (thiourea dioxide) and Formosul (sodium formaldehyde sulfoxylate). Be careful to determine the safety precautions required for each method you consider using - do you need to get a gas respirator? Discharge agents are all more hazardous than dye and must be treated with great respect.