For any surface treatment with dye such as dye painting, stamping, stenciling, any kind of monoprinting, or deconstructed screen printing, I like to pre-treat my cloth in a soak of soda ash, also known as sodium carbonate, also known as fixer or activator in some circles. This prepares the molecules in the fabric with soda ash, so that I don’t have to add any extra liquid to my paint. The fabric is ready and waiting to activate the dye as soon as I apply it. A nice warm day is also good so that you can air dry your cloth outside on the clothesline. You can air dry it inside also; I just happen to like to hang it outside. Just don’t put it in the clothes dryer or iron it in any way, because it will turn brown….something about that high alkalinity…
I buy my soda ash/sodium carbonate at various places, such as pool suppliers, Walmart when they clearance the summer stuff, and Dick Blick. If I am at Festival or Paducah quilt show, I always purchase extra from Pro-Chem’s booth. I never have it shipped to me because of the weight. Of course now, I sell it when I vend at retail shows, so I order it from Jacquard.
My recipe is to use 1/2 cup of soda ash to every gallon of hot water. Several dyers I know call for 9 tablespoons, but 1/2 cup is 8 tablespoons and gives me a very high alkalinity, as evidenced by the ph tape in the picture below. I learned this from Robbi Eklow. Since I am usually preparing several yards of fabric at a time, I will mix two gallons of hot water with 1 cup of the soda ash in order to have plenty of solution. I use a 5 gallon laundry detergent bucket.
This is one of those cups that comes in every box of granular laundry detergent. I save them for measuring my dyeing supplies. The smaller one is 1/2 cup (I checked), so I quickly measure 1/2 cup of soda ash into my soaking bucket. Then using HOT water (so it dissolves), I stir with a wooden spoon which is reserved just for this task. My ph tape tells me the alkalinity is good, so my pre-soak is ready.
The ph tape is available at both dye houses, Pro-Chemical and Dharma Trading Company.
Now it’s time to soak. Since I purchase PFD (prepared for dyeing) cotton (so I don’t have to pre-wash), I immediately submerge my cloth in the bucket. I know some people go ahead and pre-wash their pfd to remove any oils or dirt. I have never pre-washed mine and have never had a problem with any of it (except there was that one time I got cloth that was marked PFD but it actually had sizing on it…and there was a couple of bolts that even pre-washing didn’t make a difference…that’s a whole horror story all by itself). One little trick I’ve learned since I’ve been doing this for awhile is this: if you find the fabric wants to float in the bucket and not submerge and immediately get wet while you are pushing it down in the water, there IS sizing on it and you should pre-wash it, while hoping it’s not a permanent press finish, because if it is, you won’t get anything other than a pastel color on it. This means it is even resisting the water, which spells trouble.
Soak it 20 minutes or longer, which will not hurt the cloth. Using latex, vinyl or rubber gloves, wring the pieces out and give the cloth a spin in the washer spin cycle. Make sure it doesn’t rinse at all, or you will have to soak again. You don’t want the washer to rinse out your soda ash. Hang on the line to dry, then fold up and keep separate from your other cloth. It may be helpful to mark it in some way. You can keep it this way for a fairly long time before using. Leftover soda ash solution can be saved for a long time and re-used, so don’t throw that away.
I probably should clarify that these are soaking instructions for cotton only! For silk, you can use soda ash or white vinegar for the pre-soak. My experience has been that you will get different colors depending on what the pre-soak is. It’s an interesting side effect. Silk cannot have soda ash on it for very long without affecting it adversely. I do not soak silk in soda ash and leave it. I usually treat silk with white vinegar.




















Thanks for sharing your knowledge! When you say the pre-treated fabric can be kept for a fairly long time, do you have an estimate? Also, when you are ready to dye, can you/do you wet the pre-treated fabric before applying the dyes?
Thank you for this information. Knowing I can buy the soda ash/sodium carbonate in local pool supply stores or dept stores is a big help. I didn’t know about the ph tape either. New to dyeing fabric. Thank you, thank you.
You are so welcome Gloria…good luck with your dyeing projects!
Since Arm and Hammer washing soda is sodium carbonate, can you use this instead of purchasing a pool chemical? Also, what do you do with your cotton prints once they are made as a screen print? I’ll be taking a class with Kerr Grabowski but I think she uses a lot of silk.
like lora, i want to know how long i can keep pre-soaked cotton before painting on it. weeks? months? before the ash eats the fiber away.
Sharon, if Arm and Hammer washing soda is strictly sodium carbonate, I see no reason why you can’t use it. I have heard there are other things in it. I use all the cloth I screen print in work for the wall mostly.
Jeanne, I can’t really give you an expiration date on how long to keep your soda soaked cotton. But I do have some left from last summer and it has not been eaten away. I’m not sure you have to worry about that with cotton. Silk is the fabric that you don’t want to leave the soda ash on for very long. But I have never heard of cotton having problems.
hey, thanks for the reply. both silk and wool are allergic to soda ash, so i didn’t worry about it until some t-shirts i made using the soda soak method developed holes in them soon after. this time, i’m making a huge dragon sari, and am hoping for the best.
a huge secret revealed…soda ash is sodium bicorbonate,
it can be expensive when bought in bulk,
I have found that arm n hammer washing soda is exactly the same and is inexpensive and found at most grocery stores
thank you, sonia for the soda ash/sodium bicorbonate clue. I am rust dyeing in Nairobi, Kenya and materials are not always available.
Julie, let us know how your dyeing goes. My understanding is that soda ash is sodium carbonate…baking soda is sodium bicarbonate. I don’t believe that they will do the same thing. I once accidentally bought the bi-carbonate in the swimming pool section, but when I discovered it I was too scared to use it. Check online about the differences.
I’m going to be preparing first piece of cotton for painting and wondering how many yards of fabric can be safely soaked in your half cup soda in 1 gal. hot water,
thanks
ct