Airstream Airstream
I'm back at it after a break from silk painting. I'm still using Procion H liquid dyes. For some reason I'm having some major bleeding issues in the upright steamer. I spent a few years using this steamer, in a professional context doing batch after batch which generally worked fine. I would even then have the occassional failed batch. But mostly it worked. So more recently I've had a few totally failed batches which turned me off to the whole process for some time, now I'm trying to carefully pinpoint and solve the issues and move forward. Mostly I paint the dye onto the silk, either with no resist or using a wax resist.

I'm using: Dharma's upright steamer, cotton steam sheets, aluminum foil capping the ends of the roll; the bleeding is not from water getting it directly wet (i.e. dripping on it, splashing in from the bottom.) The steamer does seem to be achieving the correct temp.

1. I'm using chemical water (urea, calgon, ludigol only) for 100% silk. Causing too much wettage of the fiber? Should I use water only? I have hard water, does this matter? Will filtered water be better? What PH is best?

2. Why do some chem water recipes require baking soda? What does it do? No matter what, it still must be steamed, right? (I do rayon/silk velvet also, chemical water is required because of the rayon?)

3. What is the shelf life of the H? Maybe mine got too old and won't set anymore?

4. I read in some post that H can be used as acid dye, how exactly would this work? What's the forumula/recipe for doing this?

5. Soda ash and H: I read about this somewhere also, what is the process? Does it work without steaming? Will it work for silk painting using wax resist or is it more for immersion? What about for silk/rayon velvet?

Thanks so much in advance for any help.

take care,
Quote 0 0
pburch pburch
You don't need [URL=][U]urea[/U][/URL] if you're steaming or immersing your dyed fabric. Urea is used as a humectant, which you don't need for steaming. Try leaving it out, to see if you get better results without it. You do need [URL=][U]ludigol[/U][/URL] to keep from wasting dye as the result of chemical reduction at high temperatures, and you do need [URL=][U]water softener[/U][/URL] if you have hard water. Jacquard's Calgon is the right stuff; don't try to use grocery-store Calgon, which is something else altogether.

[URL=][U]Baking soda[/U][/URL] turns into [URL=][U]soda ash[/U][/URL] when it is steamed. You need one or the other with Procion H, and you do need to either steam, or heat your dyebath to 176°F. Procion H is less reactive than Procion MX dye, so it has to be heated, one way or another. The reaction between the Procion H dye and the fiber will not proceed without heat. Baking soda is gentler to silk than soda ash is, until it is steamed; you can leave baking soda on silk longer, without damaging the silk, than you can soda ash. Silk is much more prone to damage from high pH than cotton or rayon are, though silk is far better about it than wool is.

All fiber reactive dyes can be used as acid dyes, too, if you substitute an acid (such as vinegar or citric acid) for the base (soda ash or baking soda), and use heat (steaming or simmering). They are less washfast when used as acid dyes than when used as reactive dyes, so it's not always the best idea. See my page, "[URL=][U]Fiber reactive dyes on protein fibers[/U][/URL]".

Quote 0 0
JennyR JennyR

Here is what our president, Michael, had to say:

1.) [font=Tahoma]I am assuming you are working on silk and not cotton. I have seen many painters with the same problem which is most directly related to the addition of too much urea. Urea is a humectant-it absorbs water (steam) rapidly. Silk cannot tolerate much moisture before it begins to bleed. Urea is an essential additive when painting on cotton but not so important with silk. In fact, I like a system which is very clean. That is, a chemical water that has practically nothing in it. My suggestion is that you add just a quarter of the urea that you are adding now. Use distilled water so you don't need calgon and ludigol on silk-it is not necessary. You will get great colors with just H, urea and a pinch of bicarb OR vinegar. Bicarb (ph of 9 or 9.5) is fine as an additive but remember silk (protein) does not like a high pH for long. So after steaming neutralize the pH with some vinegar in the wash water. Instead of bicarb a small amount of acidic acid (5% in vinegar) can be used instead. [/font]
[font=Tahoma]Put a thermometer at the top of your steamer. It should read 212 F. Anything less insulate your steamer. Steam time should be as little as poss. To avoid bleeding: 15-20 min at 212F. Do steam trial test. Also, very importantly, make sure you are painting with final dye concentrations no more than 8% for dark colors and 3% for lights like yellow. Also, do dye concentration tests. Good luck.[/font]
[font=Tahoma]2.) [/font][font=Tahoma]Chem water is a must if painting rayon. Rayon needs urea to develop good color. Soda ash is twice as strong as sodium bicarb so in situations where you are painting or printing, thereby leaving the color on the material until it is processed, it is safer to use bicarb.[/font]
[font=Tahoma]3.) [/font][font=Tahoma]You don't want reactive dyes to be left for too long in a liquid, but, that said I have seen very little loss of color yield with liquid H that was 2-3 years old.[/font]
[font=Tahoma]4.) [/font][font=Tahoma]Reactive dyes act like acid dyes when acidified. There has been a lot of work along these lines with cold water reactives like the MX series. What one does is simply add an acid to the dye bath instead of a base.[/font]
Quote 0 0