Category Archives: dye auxiliaries

What to do if soda ash makes your skin break out

Name: Bob
Country or region: USA
Message: I have been dyeing for many years. I have had no reaction to soda ash up until about 2 months ago. About that time, I got a huge rash/blisters on my hand that I thought were caused by poison ivy/oak. Now, whenever I touch fabric that has soaked in soda ash, I get pimple-like things on my hands and forearms. I am sure they are caused by overexposure to the soda ash. They are quite irritating.

Do you think my soda ash soak is too “hot”? I have been using 100% sodium carbonate that I buy in ph Up in the pool supply store. Do you think that it would be less irritating if I were to use light soda ash as supplied by ProChem?
I know that you can use soda ash directly in the dyes but it gives you a shorter life for the dyes. I am not sure about that process.

I generally dye about 100 shirts a week, over a 5 day period. I have been dying with procion dyes for 25 years and never encountered this problem before. The weird part is that most of the skin irritation occurs on my left hand while my right hand is relatively free from any irritation.

Thanks for any help you might be able to give me.

Have you been soaking your fabric in soda ash before tying it? If so, the answer is to stop doing that. Moisten your fabric with plain water (a spray bottle is nice for this unless you prefer to soak it) and tie it. Plain water works just as well as water for the tying step, for those who prefer to tie wet fabric, and then, after tying, it can be displaced by the soda ash presoak. After you have tied your fabric, put on heavy duty rubber gloves to place it into your soda ash soak. Use a relatively strong soda ash presoak mixture, one cup per gallon, rather than the nine tablespoons per gallon in the ProChem recipe, to make up for the extra water (though soda ash works well over a surprisingly wide range of concentrations). Get a mop bucket with a wringer to squeeze out the extra soda ash solution after soaking, so you don’t have to handle it so much by squeezing out extra soda ash solution by hand. The spin cycle of some washing machines works well for this step, but other washing machines spray on extra water during spinning, which is no good at all. Wear reliable gloves whenever you’re near soda ash, including your freshly dyed items before rinsing out.

If you are line-drying the soda ash into the fabric before dyeing, after the presoak but before tying, the fabric is probably too irritating for you to handle at all. The dry soda ash tends to get into the air during the tying step.

Adding soda ash directly to the dye works well if you will be using the dye right away, but as you note the dye goes bad only an hour or so after adding the soda ash to it. There’s a good recipe for this technique on my dye thickener page.

To protect your hands while dyeing, try latex-free gloves to see whether a latex allergy might be contributing to your problem; you can choose vinyl or nitrile gloves, instead. There are some nice elbow-length nitrile gloves available for dyeing. Look for the type with a cotton lining, as well as the thinner unlined type for when you need more sensitivity.

Depending on your source of clothing blanks, it’s possible for them to be contaminated with formaldehyde and other chemicals when you receive them. (This is less likely with clothing that is marked “prepared for dyeing”.) Wear gloves to handle them as you place them in the washing machine for pre-scouring.

Light soda ash will not make any difference. It’s the exact same chemical, just a little bit fluffier maybe. It doesn’t matter whether you order soda ash from a dye supplier, or purchase soda ash as a pH increaser for swimming pools; the latter is often more convenient.

There are other chemicals that can be substituted for soda ash, such as trisodium phosphate (TSP), but it seems likely that your problem may be due to irritation from the high pH of the soda ash, rather than due to a specific allergy to soda ash. If this is the cause, then switching chemicals will not help at all, because all of the chemicals that can be substituted for soda ash, for dyeing with fiber reactive dye, produce a similar high pH. It’s the high pH that activates the cellulose molecule so that it can attack the dye molecule. Trisodium phosphate produces a higher pH than soda ash, so it is even more irritating.

All of these high-pH chemicals tend to react with the natural oils in your skin, producing soap. That’s why your skin feels so slippery after you get soda ash on it. What you feel is the newly created soap. It is extremely irritating to the skin to lose the protective oils. In addition to strictly avoiding all exposure of your skin to soda ash, you will need to replenish the oils. Avoid exposure to very hot water. You will probably want to apply lots of moisturizer to your hands frequently throughout the day, especially after every time you have gotten them wet, and before going to bed at night. Be aware of anything that might be causing an allergic reaction; if you are concerned about an ingredient in your skin moisturizer, you can apply plain vegetable shortening, such as Crisco, to your hands. It is distressingly greasy, but very suitable for extremely sensitive skin; some eczema sufferers like to put it on at bedtime and wear thin cotton gloves. If your problem continues after you have stopped exposing your skin to soda ash, you should see a dermatologist.

For more information about soda ash and its role in dyeing, see my FAQ page What is soda ash, and what’s it for in dyeing?

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Is there a way to dye a white rayon dress different colors without having them bleed into each other too much?

Name: Raileena

Country or region: USA

Message: I bought this white rayon dress that I thought might look really cool if it was all different colors. It also has small flowers that can be colored in, so I was just wondering if there is a way for me to dye it without having colors bleed into each other too much how would I do that? Would I add the sodium acetate to make the dye paint-like and apply it? Also would I have to add one color at a time, and wash it and everything before adding another color to avoid too much bleeding? Thank you!

You can easily dye a washable rayon dress many different colors, without the colors bleeding together, if you use the right kind of dye. If you use a good tie-dye type of dye, which is called fiber reactive dye, you can apply many colors at once. The key is to avoid all-purpose dyes. Don’t use Rit dye! All-purpose dyes, such as Rit, always bleed together every time the garment gets wet, for the life of the garment. Better quality dyes avoid this problem altogether by bonding tightly to the fabric where you put it.

Rayon is a reprocessed cellulose fiber. It can be dyed like any other cellulose fiber, such as cotton, as long as you are careful not to damage it. The one problem with rayon is that it is fragile when wet, so don’t let it get into a washload with something heavy like jeans, and do consider hand-washing or putting it in a mesh lingerie bag for washing. (The question of washing is relevant to your question because you will have to do a lot of washing after you dye the dress, to remove all of the unattached dye.)

What you need to do is get some good fiber reactive dye, such as Procion MX dye. You can find these dyes in any good tie-dye kit, such as the Jacquard tie dye kits, which are often available at local crafts stores and fabric stores. Avoid hot water dyes. If you want a wide choice of dye colors, and access to more helpful products, order online from a dye supply house such as Dharma Trading Company, Colorado Wholesale Dyes, or PRO Chemical & Dye. Dharma is also a good source for additional dyeable rayon dresses.

You will not need to use sodium acetate in dyeing your rayon dress. Sodium acetate is used when dyeing protein fibers, not when dyeing cellulose fibers like cotton and rayon. But I think actually you may be thinking of sodium alginate, which is a thickener. (See “Sodium alginate, Superclear, and other dye thickeners”.) Its use is completely optional, but it can be helpful depending on your style of dye painting. You can use a dye thickener if you want your dyes to have a more paint-like consistency and apply it with a brush or sponge, or you can use your dyes unthickened in a watercolor style and apply it directly from a squirt bottle; even unthickened colors will creep only a short distance along the fabric. Order alginate from a dye supplier such as Dharma Trading Company or PRO Chemical & Dye. (See “Sources for Dyeing Supplies Around the World”.)

Once you have your good Procion dyes, mix a cup of sodium carbonate (soda ash or washing soda) with a gallon of water and soak your rayon dress in it. After fifteen minutes to let the sodium carbonate soak into the fibers, remove the dress from the mix and squeeze out extra water. You can apply dye directly to the wet dress, or you can line-dry the dress, which will leave the dry soda ash in the fibers, ready to react with the dye.

DIssolve the dye in water, either following the directions on the package (for a tie-dye kit) or following instructions for how to tie dye (see “How to Tie Dye” and “Hand Dyeing – basic recipe for Procion MX dyes on cellulose or silk”). Put the dyes into the pointy-tipped squeeze bottles sold for use in tie-dyeing. Lay the dress out flat on a surface that won’t be damaged by the dyes (such as a plastic table protected by a plastic tablecloth with some old towels or paper towels on top), and dribble the different colors of dyes where you want them. If you only want bright colors, avoid placing opposite colors immediately adjacent to each other, such as purple next to yellow, red next to green, or blue next to orange, as these color combinations combine to make muddy browns.The wet dye on the dress should be darker in color than you want, because not all of the dye will attach; some will be washed away, which results in a lighter color than you see during dye application.

After you have thoroughly covered your rayon dress with as many colors as you want, cover it with plastic and leave it alone in a warm place (70 degrees F or above) at least overnight, for the dyes to react with the rayon in the presence of the soda ash. Covering it with plastic is to help keep it moist, since the dye reaction stops once all moisture has dried up. It is better to leave the dress to react longer than necessary, rather than less time than necessary, because the extra time makes sure that all of the dye molecules have reacted, either with the fabric or with the water. The means there will no longer be any active dye present to cause staining with colors in the wrong places, when you wash out the excess dye.

The next day, wash the dress once in cool water, to remove the soda ash and some of the dye, then wash two or three times in the hottest water available. To avoid unnecessarily abrading the rayon fiber, which is very weak when it is wet, you can soak the dress for a while in extremely hot water (even boiling water is okay for washing out Procion dyes), then wash out by hand and then repeat.

If you prefer, you could dye the entire dress in multiple colors for the background, wash it afterwards, and then start all over again, line-drying the dress after soaking it in soda ash again, applying just the colors inside the flower patterns. This will reduce the amount the colors small patterns blend with the background color, and is a particularly good idea if the background color you apply contrasts strongly with the colors you apply inside the flower patterns. If the dye seems inclined to spread much more than you like, either apply less dye, or thicken this dye with sodium alginate.

You can produce a really fantastic dress in a unique color pattern. Note that synthetic trim, such as the white stitching that holds the seams together, and any edging or lace, will almost always stay white, after washing out the excess dye, though sometimes a turquoise dye will stain it.

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Does chlorinated tap water affect the fibre reactive dye process?

I’m currently doing a lot of Fibre reactive dyeing, and trying to improve my results by fine tuning all the variables.

I’ve looked everywhere for this info, not having any luck. Does chlorinated tap water have any appreciable effect on the fibre reactive dye process? Our water at home is very good well water, but at my studio it’s pretty stinky, yellowish, chlorine filled stuff.

I have a lot of reading to do by the looks of your very informative site! I’m some glad to have found it, and your wealth of knowledge.

Cheers from Atlantic Canada,


Water quality does make a difference. Chlorine’s not the only contaminant involved, if your water is stinky and yellowish. Some contaminants are much more important than others.

Chlorine for disinfecting water supplies can be added as chlorine gas or as hypochlorite (which we call household bleach), or the chlorine compound chloramine can be added instead. Chloramine is more difficult to remove. Chlorine can be removed with hydrogen peroxide, or by evaporation, but chloramine cannot. Both chlorine and chloramine can be removed with Anti-chlor (sodium metabisulfite), which is readily available from dye suppliers, as well as from sellers of supplies for home beer-making and for photography. The same chemicals used for neutralizing chlorinated water are also used for neutralizing chlorine bleach used as a discharge agent; see How can I neutralize the damaging effects of chlorine bleach?.

When my area’s public water supply changed from chlorine to chloramine, we began to notice more fading of clothing, even clothing dyed with good Procion dyes. The colors still last a long time, but a garment that has been washed a hundred times is noticeably paler in color than when it was new. It would help if we were to always add anti-chlor to every washload, but, since our problem is not very severe, we haven’t felt it to be worth the bother.

Dyers often need to be aware of hard water, which is water that contains calcium and/or magnesium ions. (See Dyeing with hard water: water softeners, distilled water, and spring water). These ions are what combine with soap to make soap scum, which has to be scrubbed off of surfaces. Hard water has more than one consequence in dyeing. It can result in colors that are not as bright, it can make it seem as though your soda ash is not dissolving completely even when it is (because of the formation of insoluble calcium carbonate), and it can result in the formation of dye/calcium complexes that are more difficult to wash out of the fabric, resulting in later color bleeding that makes it seem that the dyes are not washfast, when in fact it is only incompletely-washed-out unbound dye. The solution for hard water is easy. Buy sodium hexametaphosphate, also known as water softener. Sometimes sodium hexametaphosphate is sold under the name of Calgon (Jacquard Products still uses the Calgon name on their water softener for dyeing), but beware of other products also sold under the Calgon name, which contain carboxylates rather than phosphates; carboxylates which are not desirable for dyeing. Do not buy any liquid form of Calgon, since these generally contain carboxylates rather than phosphates. Mix sodium hexametaphosphate in the water you use to dissolve your dyes, and in the water you use in your dyebaths; also add it to your wash and rinse water, when washing out excess unattached dye after dyeing. The amount needed varies according to the hardness of your water supply; I can tell you more about this if needed.

Neither chlorine nor hardness will make water yellow. If your water is yellowish in color, it has additional contaminants, which can be a big problem. I’m concerned that you may also have iron. Iron is one of the worst water contaminants for dyeing, though it is safe to consume in the quantities likely to be present. Iron tends to “sadden” many dye colors. It’s used as a mordant with natural dyes to produce dark, dull colors, but it can also affect the colors of synthetic dyes. If your water is contaminated with iron, you probably won’t want to use it for dyeing bright colors. You cannot remove iron with phosphates or with anti-chlor. Water softening systems work well for removing hardness minerals from water, but they do not generally remove large amounts of iron. Specialized water purification systems that can remove iron are more expensive than ordinary water softening systems. A reverse osmosis system would work. You can use distilled or deionized water. Otherwise you may be reduced to bringing water to your studio from home.

To see how severe your problem is in practice, you should do some small scale tests of dyes you like, using only distilled water in one set, while using the stinky yellowish tap water available at your studio in a second set. Perhaps in a third set you could use tap water that you have treated with anti-chlor and hexametaphosphate. I would be interested in knowing how significant the difference turns out to be for you.

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