community of dyers

Thanks for that reply, Paula. So, had I known from the beginning about this, at what time could/should I have microwaved? Thanks for all your help,

Fulvia Luciano
www.fulviastudio.com

It's best to give the dye some time to soak into the fiber, maybe half an hour or so, before microwaving. Obviously a heavy tight weave like canvas will need a lot more time than a thin sheer fabric. The latter probably needs very little time.

I was going to write "give the dye and soda ash some time", but my experience of soda ash is that it diffuses very well through the entire container even though I just add it to the top, so I don't suppose it would take very long to penetrate the fiber, either. A molecule of sodium carbonate is so much smaller than a molecule of copper phthalocyanine (in turquoise dye).

-Paula

Paula,

So many of the questions you answer here have been "answered" in your Q&A and technical articles. Some of them in great detail.

I'm gratified to see this elucidation, however, since it gives me greater clarity (as to WHY) than the directions on "crackle dyeing" I read (and re-read and re-read) before I started stuffing velvet into glass jars.

I have been taking it on faith that dye needs time to diffuse into fibers, so I give it meandering time before putting soda ash solution on it and popping the results in the microwave. But I have been a trifle uneasy about how the soda ash could be so quick relative to the dye, on a molecular basis. (Especially since it visibly takes time to dissolve the crystals.*) So it's molecular size. Ahhh.

What I would love to say to your readers, probably again and again, is to READ the technical stuff.

It's geeky and makes you move over from your "oooh-pretty" right brain playground into the left brain space, but it's probably going to be well worth knuckling down with the homework, as a whole new level of understanding opens up to you. And that would also make for fewer embarrassing mistakes, based in a "lore" approach rather than an understanding of the actual processes at work.

I'm still dazzled in amazement at the ignorance of the nice ladies who wrote the tray dyeing book. They say right there in print (and I quote) "Soda Ash doesn't like being dissolved in hot water," and tell you to start with tepid water! So I wasted a lot of time trying to do things their way, fretting over *undissolving crystals, until I finally accidentally hit some with the hot water I'd used before I tried following directions. They dissolved in hot water before, and did so after. Heat is the universal catalyst, as everyone learns in any introduction to chemistry. How on earth these ladies decided on their ideas about the way things work is a mystery to me, but it illustrates how even very experience people can take some chance observations or some handed down (wrong) information, and make it "the way things are" despite the disservice it does them in practice, again and again, as they make it gospel and pass it along!

I've done LWI in the microwave where the items aren't covered by anything (though I do have a dedicated studio microwave, so splatter is not a huge issue). But perhaps the way I'm doing microwaving means no need to wrap with a cover -- I nuke the item for a total of about 2 minutes, in spurts of 30 secs nuking, 30-60 secs resting, etc. I've seen people mention doing cotton for a total of about 4 minutes, usually in 30-60 sec intervals with rests in between.

A couple of years ago in one of Carol Soderland's workshops, she had us do a series of experiments with 4 samples -- microwaved sample, and then 3 samples processed for 2- , 4- , and 24-hours (using muslin). For MX-8B (fuchsia) and MX-GR (tangerine), the samples were indistinguishable. For MX-G (turquoise), there was a difference in richness between the 24-hour sample and all the others, but the microwave sample looked about equivalent to the 4-hour sample and any normal person would call the microwave or 4-hour sample "rich, deep turquoise". Our microwaving process was between 2-4 minutes in spurts and with rests. In all samples, the process was: 15 minute bath with dye only, then add soda ash, give that another 15 minutes (so total, like Paula's way, of 30 minutes), then nuke the sample (or process for the remaining time if you're not nuking).

Maybe don't use a piece of plastic wrap (save the planet and all that)? I think I've seen someone mention using a glass pyrex type cover over their container to prevent splatter -- at your local Goodwill center you could probably pick up several different sizes for a very low cost. Or maybe by doing the nuking in short spurts, or where there's room for the steam to escape without causing splatter, you can save that piece of plastic for a different use.

What I like about covering and microwaving is the lovely steam that builds up in the container. Since I'm dyeing silk with vinegar, the heat is more important.

In the interest of not using endless pieces of plastic, I bought a bunch of plastic food containers at the dollar store. I pop the cover on and microwave for 3 minutes at 50% power, because that builds in "rest" periods to avoid an explosion. The containers wash up nicely.

Another advantage to these containers is that when I want to weight down my fabric to keep it under the dye (pre-microwaving), I just nest one inside the other and put a few soda cans on it!

my blog: A Good Day to Dye

The most important reason to cover tightly is to keep the fabric from drying out, obviously not a problem if you're using a lot of water. If you microwave fabric that is not totally sopping wet, the microwave can cook the water right out of the fabric. Then, once the fabric is dry, it turns black, starts smoking, and catches on fire. I actually did this once by accident, though not for dyeing. It was cotton fabric, but the same is probably true for any fiber.

-Paula

I think this thread has given me a good understanding of how to do the microwaving, but I have one question...

My assumption is that after you've 'nuked' the fabric (and let it cool so as not to get burned), you're ready to begin rinsing. Is this correct? Or does it still have to 'batch' some more?

(I work full-time and anything I can do to shorten the time involved for my dyeing is great!)

I like to let the dye sit on the fabric for at least fifteen minutes to soak in before microwaving, so as to avoid ring-dyeing, in which only the outer layer of each fiber picks up dye. (Longer for heavier fabrics, and much longer for really heavy fabrics such as canvas.) After microwaving, my only concern is that the dyebath be cool before I rinse it out. The reactions occur very quickly at high temperatures, when you're using fiber reactive dye and either soda ash or another high-pH chemical. The speed of reaction with Procion MX dyes increases three-fold for every increase in the reaction temperature of 18°F (10°C).

If I'm using Remazol dyes, I like to make sure the dyebath is really cool, at least to room temperature, because Remazol dyes can be stripped out by washing at a high pH in hot water, and of course you have that high pH until after the first rinse. That's not a big deal for Procion, Cibacron, or Drimarene dyes, though, because their chemistry is a bit different from the Remazol dyes. For Procion MX dyes, you really just have to cool enough not to accidentally injure yourself.

Interesting post, Paula. Can you tell by looking at the fabric if you have a problem with ring dyeing? I'm guessing that it would just cause a lighter color.

As for the Remazol stripping issue, would you ever consider adding vinegar to the first washout to neutralize the pH? I've never tried adding vinegar to the initial washout, but I've always wondered if it could minimize back-staining since the dye wouldn't be effective at a lower pH.

Ring dyeing is not obvious at first. The outside of the fiber is dyed, so it looks okay. However, once a little tiny bit of wear happens, the colored ring wears off. I think a lot of ring-dyeing is done on purpose on blue denim so that blue jeans will look worn and aged when they're still quite new!

It's disappointing for us in most other cases, though, to have the color wear off so quickly. You could detect ring-dyeing right away, after it's dry, if you cut a thread from the fabric in half crosswise and then examine it under a strong lens. Or, you can just go with what generally seems to work for you. The dye will completely soak through fine thin fabrics in moments, but take much longer for a t-shirt. It also makes a difference what the temperature of the water and fabric are, whether you've used any surfactant (such as a drop of Synthrapol or Dawn), how tightly woven the fabric is (canvas is terrible in this respect), how long you've wetted out the fabric, if you do that in advance, how well scoured the fabric is....so no hard and fast rules here.

I've never tried to correct the pH of the Remazol, but that does make sense. What I have done is dump ice cubes into a gallon bucket in which I was doing LWI, to speed cooling. I happened to have a lot of ice handy, so why not?

-Paula

Just thought I'd point out (from experience) that if you're going to place a glass container into hot water in the laundry tub make sure the glass is of a type that will not crack from being exposed to very hot water.

I had a footed vase that I used that cracked very nicely at the bottom when the water I placed it in was too hot. I usually warm up the glass containers now before placing them in really hot water. I like the shape of tall narrow vases to get the kind of crinkle effect I like.

Karen