Archives for April, 2012

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Monday, April 30, 2012

Trying to lighten a dark plum silk with either light plum dye or bleach

Name: Sumz

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Country or region: UK

Message: Hey, I dyed some silk chiffon (100% silk) a dark plum/burgundy/maroon colour with an acid dye and am hoping to tie-dye it in a lighter, more pink plum shade, again with another acid dye. My worry is that double dying it may cause the fabric to waste away (which is what happened when I tried to bleach it lighter after it was dyed) and that using elastic rubber bands may damage the fabric. Another worry is that the colours may go bad when double dyed. Any chance you could help out with some advice?

Dyeing a piece of silk twice with the same type of acid dye won't hurt it, but you can't dye a dark plum to a lighter color, because dye can only make things darker. Dye can never be used to lighten any color of fabric.

Whenever you add dye to a fabric, you are adding color. Adding more color makes it darker. Dye is transparent, so the original color always shows through. Adding one color on top of another color gives essentially the same results as mixing those two colors together. To obtain a lighter color with acid dyes, you must use less dye to start with, so the white of the fabric shows through. You can try to cover one dye with another dye only if the second dye is darker in color.

The reason why your bleaching caused your fabric to "waste away" is because bleach destroys silk. Never use chlorine-based bleach on any animal-based fiber, such as silk or wool, nor on any synthetic fiber, such as nylon or spandex. The way that chorine-based bleach works to remove color is by breaking apart the dye molecules; the hypochlorite in chlorine-based bleach will break up most chemicals that it encounters, including the protein molecules that silk is made of. It will do the same thing to your skin if you allow enough exposure to it. Bleach is much more toxic and dangerous than dye is, both to fabric and to people.

There is a completely different class of chemicals that can be used to remove dye, but the color you get as the result of it may not be the sort of color you are looking for. You can use a reducing-type dye discharge chemical safely on silk, if you are careful to follow the instructions. Some brands include Formosul (available in the UK from George Weil) and Rit Color Remover; see my page, "What chemicals can be used to remove dye?". If you use too much of the discharge agent, or don't follow the instructions, you may damage your silk, but the discharge agent is far gentler than chlorine-based bleach, and can be used safely if you are careful. If the color you obtain is light enough, you can dye over it with acid dye to another color; dyeing your entire dark plum piece with a light plum dye should work well, as the light plum dye will darken the pre-existing dark plum only a little.

Some dyes will discharge with a reducing-type dye discharge chemical to nearly white, though others will turn a ghostly brown or refuse to lose color at all. Depending on which acid dye you used, you may be able to learn from the manufacturers whether the specific dye color molecules you have chosen are capable of discharging, and, if so, what color they will discharge to; for example, the dischargeabilities of most of the Jacquard Acid Dyes are listed on the Jacquard Products website. [PDF]

If you happen to have chosen an acid dye that will discharge well, you can apply a discharge agent such as Jacquard Discharge Paste or Deco Reco Decolourant to just those areas you wish to lighten in color, or you can tie the silk tightly, as for any tie-dyeing, and then heat it in a discharge bath with Formosul, Rit Color Remover or another discharge chemical, carefully following a good set of instructions. If you can't use elastic rubber bands without damaging a delicate fabric, try tying with string, instead. Try different types of string to see which you prefer; I like to use a wax-coated polyester string called artificial sinew.

There is one other possibility for placing a light pink plum color on top of a dark plum/burgundy color. Instead of using dye for your second color, you can use fabric paint. Some paints are harsh and stiff on the fabric, but some brands of fabric paints are thin enough to be very appealing on silk. Look at your local crafts store, or on the website for a dye supply company (such as George Weil, in the UK), for any fabric paint specifically marketed for use in painting silk. It's important to note that most fabric paints are transparent, so they can cover a darker color with a lighter one only if they are specifically labeled "opaque"; however, if you're interested in a metallic or pearlescent effect, diluted Jacquard Lumiere can work beautifully on silk. Jacquard Dye-Na-Flow is available in a white color which will not work well in covering a dark-colored fabric, but may suffice for lightening the color a little. Test it first on a scrap piece of colored fabric.

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Friday, April 27, 2012

How to mix a very dark brown that is not reddish or purplish

Name: Trina

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Linda Knutson's
Synthetic Dyes for Natural Fibers

Country or region: USA

Message: Hi Paula,

Your website is amazing. I have scoured it and have found many useful tips. I am trying to get a VERY dark brown. I have tried every Procrion brown dye offered by Dharma and cannot get the right color. They either too pale, way too red or even too purple.

Can you suggest a mix of colors to achieve a dark NON red brown. I dye 4.5 pounds of cotton in a top loading machine.

Other than color mixing, do you have any other tips to get a dark brown? Soak for more time? More salt? Warmer water?

Lastly, if I do the right hue but cannot get the right depth is better to re-dye or add more dye?

If you have a piece now that is a dark reddish brown, and the reddishness is the problem, then you should overdye it with the opposite color from red on the color wheel, which is green. If the brown you have now is too orangish, you can correct it by adding blue. A brown that is too purplish can be corrected by dyeing it yellow. Overdyeing, that is, redyeing a piece you've already completed dyeing once, produces good results. It allows you to get a particularly deep, intense color, which is what you're trying to get, and it's a great way to correct a the hue of a color that you want to be darker. Since you're adding more dye to the existing color, the color you produce will always be darker than what you started with.

If you're starting over again with an undyed piece, then you can try to get a darker color this time by using more dye powder. You can use up to 10% of the original dry weight of the fabric; some people even use as much as 12%. Since your cotton weighs 4.5 pounds, which is about 2000 grams, you could use up to 200 grams of Procion MX dye powder, which is about 7 ounces dry weight, or just use one entire 8-ounce jar of dye. If you start with the same dye mix that produced a reddish brown the first time, then you should substitute green dye for a portion of the dye powder, perhaps one ounce of green dye along with six ounces of the reddish brown. You can mix the dye powder in the proportions you plan to use, and do a quick test in a plastic freezer bag with a small scrap of the fabric you're dyeing, or a similar fabric if you don't have any extra to use.

Warmer water, more time, or more salt can all help in getting a slightly darker color from a given amount of dye, but the real key, assuming you do everything else right, is to just use enough dye powder.

When dyeing in the washing machine, it's important to use a lot of salt, as otherwise the fabric and the dye tend to repel each other, so a lot of the dye ends up wasted. I usually use twenty cups of non-iodized table salt or pickling salt for a full washing machine load. If you use kosher salt, you have to measure out more cups, because each cup of kosher salt weighs less than a cup of granulated salt; the increase in volume of salt needed for two brands of kosher salt is listed on my page "Do I need to use salt, in dyeing?", or you can weigh it out. Ten pounds is a good quantity to use for a full washing machine load.

When I dye in the washing machine, I always go back about ten minutes into the washing cycle to reset the timer to the beginning of the cycle. I like to repeat this for an entire hour. There are some dye recipes that call for less time, but I don't want to risk wasting any of the dye, unless I'm trying for a pale color. As for the temperature, I use warm water, between 105°F and 110°F. If the water as it comes from the water heater into the washing machine is cooler than this, I add some hot water, as well, to reach this temperature range.

For mixing your own colors, I recommend using the basic unmixed single-hue Procion dye colors, since they are the same from one supplier to another. See my page, "Which Procion MX colors are pure, and which mixtures?", to see which dyes these are. Browns are among the most challenging colors to mix, because they contain some of each of the three primary colors (red, yellow and blue). A good way to start is with orange dye, adding blue dye to it as needed, then adding yellow if the resulting mix is too purplish, or green if it's too reddish.

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Wednesday, April 25, 2012

Can I dye a canvas convertible roof on a Mustang? Do you know if that is possible?

Name: Karen

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Vinyl "dye" is not dye at all, but instead a paint made by suspending insoluble pigments in a mixture of petroleum-based solvents such as toluene and butane.

Country or region: New Hampshire, USA

Message: Can I dye a canvas convertible roof? My husband has a mustang with a beige/tan roof and he would like to dye it black. Do you know if that is possible?

Probably not. Any convertible roof must be coated with some sort of durable water repellent finish, to keep it from getting soggy every time there's a little rain. Durable water repellent finishes can never be removed thoroughly enough to allow for good dyeing. The water repellent finish will repel not only water, but also both dye and paint. A true dye will just sit on the surface, unable to fully contact the fibers of the fabric underneath. No real dye that you apply will last long. Even paint will fail to penetrate fully, and will tend to wear off relatively quickly.

Furthermore, there's the question of what fiber the canvas is made of, since the type of dye used must always be matched to the specific fiber. It's certainly not the cotton canvas some of your clothes may be made of. Cotton is extremely easy to dye, because there are excellent fiber reactive dyes available that will form a permanent chemical bond to cotton at room temperature; no heating is necessary. Unfortunately, a water-absorbing fiber like cotton is not the best material to make a car roof out of. In contrast to cotton, synthetic fibers such as polyester can be dyed only in the presence of high heat, meaning you have to boil them with the dye: clearly an impractical proposition for a car roof, since you can't possibly own a cooking pot large enough to hold it. Your convertible roof might be made of polypropylene canvas, which is impossible to dye at all, after manufacture has been completed. Polypropylene is dyed by adding pigments to the liquid the plastic is made from, before the fiber is even made.

There is a product which is called "Convertible Top Dye" which might work for you. Ironically, it is not a dye at all, in spite of the name the manufacturer has given it. It is a type of paint, designed for use on vinyl plastic, which contains insoluble pigment particles suspended in petroleum-based solvents. It is not permanent, in spite of the brand name that implies it will last forever. This product is claimed to work for up to one year, but must be reapplied whenever it cracks or fades; it will probably stay dark for less than one year, so be prepared for many reapplications. Putting the top up and down will cause stress to the paint job, encouraging the paint to show creases or to flake off. The manufacturer likes to call this product "dye" because it implies a product that will not flake off, but, since the product is truly not a dye at all, only paint, it will indeed show wear.

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Tuesday, April 24, 2012

Dyeing a silk dress with yellowish stains

Name: Dawn

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Linda Knutson's
Synthetic Dyes for Natural Fibers

Country or region: Angola

Message: I am looking for an opinion on a silk dress I would like to dye. It´s just my casual wedding gown that I want to dye to wear to a charity dinner a week from Saturday. I am in Africa and have to make due with what I have on hand (several fiber reactive colors from dharma, soda ash, etc.). The dress is ivory silk chiffon and fully lined with 100% polyester. It has a few yellowish stains on the front of the skirt. I am trying to decide which color would produce the best results and least splitting, etc. What would you try if you were me? Maybe a light blue? I´m thinking that a lighter color would be better since the lining won´t dye at all probably. But I´m worried it may not cover the yellowish stains. Any advice would be greatly appreciated.

That can be a real problem. Dyeing to cover up stains often doesn't work, unless you either choose a very dark color, or dye the dress in variegated colors instead of a single smooth solid color. If you dye an ivory-colored dress with yellow stains with a light blue dye, then the stains will end up greener than the rest of the dress. The ivory color of the dress itself will make the light blue turn a little bit greenish, but not as much as the stains do, so the stains will still show.

Would you be willing to try dyeing the dress in multiple colors? A very popular method of dye application for this effect is called low water immersion dyeing; the same dye you would use in a large volume of water to make a single solid color can often be used in a very small amount of water for a more interesting variation in color. You can do this with multiple colors of dye, or with a single color of dye for darker and lighter splotches. I think it'd be best to include a little bit of yellow; a little bit of yellow plus a larger amount of blue or red would work nicely in LWI, and the yellow stains would be made much less obvious. See "How to Do Low Water Immersion Dyeing".

Is this dress washable? You must wash the dress before dyeing it. I assume you've already done as much as you can to remove the stains, as the best approach is always to remove the stains before dyeing, if possible. Hot water works better than cold water for stain removal, except for protein-based stains like blood or milk. Prewashing is always very important before dyeing, as there may be additional stains you have not seen because they are invisible now, but which may resist the dye, resulting in obviously lighter spots.

As you know, the polyester lining will not take the fiber reactive dye. Depending on the design of the dress, this might look just fine. Keep in mind, though, that the stitching at the seams will also refuse to take the dye, because it, too, is almost always made of polyester.

Your Procion MX dyes can be used as fiber reactive dyes on silk, using soda ash; this will tend to make the texture of the silk a little softer and less stiff. This is usually fine, though. These same dyes can also be used as acid dyes, by substituting vinegar or another mild acid for the soda ash. (Do not use soda ash and vinegar at the same time, as neither will work when they are used together.) You will see less change in the texture of silk if you dye it using an acid instead of soda ash.

Note that any pre-mixed dye colors will tend to produce surprisingly different colors on silk than you would get on cotton, and the Dharma fiber reactive dyes are optimized for cotton, so the color name and color chip reflect the results you can get on cotton, not silk. This means that, while the single-color unmixed dyes will produce the expected colors, a blue mixture might end up more of a purplish blue than you expect, or more of a greenish one., depending on which dyes were used to make the mixture. (See "Which Procion MX colors are pure, and which mixtures?", to see which colors will stay the same on silk as on cotton.)

As a rule, you will see much less color shift on silk if you use your Procion dyes as acid dyes, substituting vinegar for the soda ash. For more information on using fiber reactive dyes as acid dyes, see "Fiber reactive dyes on protein fibers".

If you do use soda ash to dye your silk dress, using the same recipe you would use for dyeing cotton, it's a good idea, when you are done with dyeing and washing out the excess dye, to restore the pH of the silk by rinsing it in water to which you have added some vinegar. This helps to restore the feel of the silk, and it is good for protecting the silk from damage, as well. To make this final rinse, for one gallon of water, add eleven tablespoons of distilled white vinegar (which contains 5% acetic acid), or 160 ml of vinegar per four liters of water.

Good luck in dyeing your dress.

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Thursday, April 19, 2012

Why didn't my 98% cotton/2% spandex jeans dye? Can I remove the polyurethane, or use another dye?

Name: Susan

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Linda Knutson's
Synthetic Dyes for Natural Fibers

Country or region: US

Message: I have two great pair of jeans that I need to dye, after two attempts with fiber reactive dyes, I realized the 100% cotton feel is actually 98% cotton and 2% polyurethane. Can I remove polyurethane? Can I dye with another type of dye? Please help.

You cannot remove the polyurethane. It is probably woven right into the fabric, intermixed with the cotton. This is normally not a problem at all! Polyurethane is what spandex is made of; spandex is also known as elastane or Lycra. It's usually very easy to dye cotton jeans or other cotton clothes that contain 2% spandex mixed into the fiber, or even up to 20%. The stretch polyurethane does not take the fiber reactive dyes, but it doesn't matter, since it doesn't interfere with the ability of the cotton fibers to react with the fiber reactive dyes. Coloring 98% of the fiber is always sufficient. You usually can't even see the undyed 2% except when the fabric is stretched.

There are fabrics with a polyurethane coating, made to feel like synthetic leather, but, since your jeans feel as though they are 100% cotton, that's not the issue here. A faux leather coating made of polyurethane or another plastic would make your jeans undyeable, and it could not be removed sufficiently to allow good dyeing. However, in that case the fabric would not feel like natural cotton on the surface at all, no matter how high the cotton content of the original weave of the fabric.

What brand of fiber reactive dye did you use? Did you use soda ash or washing soda along with it? Perhaps something went wrong and you accidentally left out the soda ash altogether. This has been known to happen on occasion, and prevents the dye from fixing.

Also, soda ash does not go bad, but fiber reactive dyes certainly do. If you leave a jar of fiber reactive dye in a hot car with the windows rolled up in sunny weather, the dye can lose its ability to react with cotton within a day, though it should last at least a year or two when stored in a tightly sealed container at room temperature. Fiber reactive dye purchased from a hobby store can sometimes (rarely) be so old before you ever buy it, or have been exposed to so much heat, that it's completely nonreactive and needs to be replaced with fresh dye. (I've never known this to happen with dye ordered directly from a good dye supplier.)

Not all types of fiber reactive dyes are alike; some will work at any temperature over 70°F, but others require much higher temperatures. What temperature did you do your dyeing at?

If you did your dyeing in a large bucket or a washing machine, did you add several pounds of salt? When you use a large amount of water, you need to use salt, though salt is not needed for low-water methods such as tie-dyeing. (See the recipes linked to from my page, "How can I dye clothing or fabric in the washing machine?".)

Your dyeing problem could also have been caused by a finish that was applied to the fabric, coating the fiber. Coatings are not mentioned on the fiber contents label. Were your jeans advertised as being stain-resistant or wrinkle-resistant? The coating required to make clothing stain-resistant makes the fabric completely undyeable, because it resists dye just as it does stains. Water-resistant coatings pose the same problem. The coatings used to make fabric wrinkle-resistant are less of a problem, as they allow some dye through, but they still make it difficult and usually rather unsatisfactory to dye. There's always a risk of undeclared fabric finishes, when you dye commercially-made clothing that is not marketed as PFD (Prepared For Dyeing), though it usually works out okay.

If the dyeing failed because of a mistake in how you used the dye or because the dye was old, then it should be possible to fix the problem. If the dyeing failed because of a coating on the fibers, then no type of dye will work. There is no other type of dye that will work any better on your 98% cotton jeans than fiber reactive dye.

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Friday, April 13, 2012

Where can I find a better price for Lanaset dyes in the UK?

Name: Karoly

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Books that explain how to use Lanaset dyes

Shibori: Creating Color and Texture On Silk

by Karren Brito

Color in Spinning
by Deb Menz

mixing your own colors with Lanaset dyes

Lanaset Dyes

Lanaset Dyes are among the very best dyes for hand-dyeing wool, silk, angora, mohair, and most nylons. You will also need: citric acid, sodium acetate, Glauber salt, Albegal SET, and Synthrapol.

Buy from
Paradise Fibers

Country or region: United Kingdom

Message: Hi, Paula - although I have found your site to be extremely helpful I have not written to you before. However, I am thinking of switching to Lanaset Dyes and am having trouble locating them in the UK. I know that you have often given information regarding dye suppliers in other parts of the world and wondered if you can help in this instance? Ironically, I do have a supplier of Lanaset dyes in my town of Leeds, but I have contacted them and they are geared up for industrial/commercial dyeing and their prices are £19.95/approx $30 per 40g-90g pot. This is beyond my means, even for three primaries and a black - it also seems quite expensive per gram, compared with Prochem and Dye's starter kit for example.

I would love to buy from Prochem and Dye, but the minimum shipping charge virtually trebles the cost. (I remember you recommended some of their liquid dyes as better value than the Jacquard equivalent, but the cost of shipping would be astronomical!)

I will buy from ProChem and Dye if I really have to, but it would be easier if I can buy the same/similar dyes here. Generally, dye seems to cost 50% to 100% more in the UK than in the states, but savings on shipping should offset some of that.

With many thanks for your website and your help,

I'm afraid I have no help to offer on finding a more economical source in the UK for Lanaset dyes. (Previously described here.)

The prices on small quantities of any sort of textile dye, that is, quantities small enough for hand-dyers, are higher everywhere I look outside of the US. There are equally expensive sources within the US, but also more economical sources here. The same Procion MX type dyes that cost less than 50 cents to dye one pound from the best US dye suppliers cost almost three times that from suppliers in Canada, Germany, or Australia, and five times that in the UK. (See "Comparison of Dye Costs".) It's not difficult to find dyes in the US that cost just as much as dyes in other countries, however, and cost often has no relation to the quality of the dye.

If the only source for Lanaset dyes that's local to you charges the equivalent of $30 for a 60-gram (two ounce) jar, as compared to PRO Chemical & Dye's average price of $10 per two ounce jar (varying by color), then tripling the cost for postage should come out to just about the same price. I would advise you to contact ProChem by phone or email and ask if they will use a less expensive (and slower) form of international shipping. If a box with $100 worth of dyes costs $50 to ship via USPS Priority Mail International Flat Rate Box (see the USPS shipping cost calculator), that would be a better deal for you than buying locally, though still quite an investment. Ask them what the slowest form of shipping for their small starter set would cost. Also contact Earth Guild in the US; they have different-sized jars, and handle their shipping differently, so it's worth checking to see which works out better for you. Earth Guild's six-color Starter Set costs $33 and is small enough in size that the shipping cost might not be onerous. If one company ships via USPS (government service) and another only via UPS (private company), the one that uses USPS might have a better deal for you. While you're at it, consider Kraftkolour in Australia, comparing their costs for dyes and for international shipping. They charge $11.50 (minus the 10% GST) for a 50-gram jar of Lanaset dye, regardless of color. It's also important to check on whether there will be a large Customs fee for importing dyes into your country. There might be a specific order cost you need to avoid exceeding so that you don't have to pay duty.

The dyes themselves are mostly manufactured in Asia, where the prices are very low, but it's completely impractical for us to buy dyes in the quantities in which manufacturers are willing to sell them. Lanaset dyes are manufactured by Huntsman Textile Effects, whose global headquarters are located in Singapore. Dye manufacturers such as Dystar have minimum order sizes of five kilograms per dye color, and I would guess the same to be true of Huntsman; the price per kilogram is far better than you'll see for smaller jars of dye, but the large package size, and large investment, are completely out of range for most of us as hand dyers.

Lanaset dyes include both reactive dyes for wool and metal complex dyes for wool. You can buy metal complex dyes (variously spelled as premetallised or pre-metallized acid dyes) that are similar or identical to some of the dyes in the Lanaset line. The Kraftkolour premetallised dyes are the Irgalan brand. I don't know about the availability in the UK, but it's another alternative you should consider looking for. I don't see metal complex dyes at Kemtex Educational Supplies, though they do have acid milling dyes.

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Thursday, April 12, 2012

Where can I purchase Retayne in Canada?

Name: Anne

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Country or region: Canada

Message: Could you please give me a location where I can purchase the product Retayne. I am located in Kelowna B.C. Canada. Thank you for your time I appreciate it.

You can order Retayne or another cationic dye fixative, such as Raycafix, from most dye retailers. (See my page "Commercial Dye Fixatives".)

G&S Dye in Toronto sells Raycafix online, as does Harmony Hand Dyes in Tisdale, Saskatchewan. I don't see it mentioned on the website for Maiwa Handprints in Vancouver, but it would probably be worth giving them a call to ask if they carry any brand of this sort of product; since so many dye suppliers carry Retayne, Raycafix, or a similar product, I will be surprised if Maiwa does not.

Contact information for these and other dye suppliers can be found on my page "Sources for Dyeing Supplies Around the World".

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Monday, April 09, 2012

Are cobalt blue containers okay for storing Procion dyes?

Name: Deana

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Country or region: USA (Austin, TX)

Message: Hi Paula,
I could use your advice and input on something. I bought some bulk dyes from Standard and I need to package them into smaller containers for student kits. I am debating between amber plastic jars and cobalt. I know amber provides the widest protection from light, but I can't find what wavelengths cobalt protects from.

How much protection do Procion dyes need from light? I've always been more concerned about moisture and air than light, but I also keep my powdered dyes in a dark space, so it hasn't been an issue. Since these jars will be going to students, I want to give them a good start. But I want the packaging to be attractive, too.

I agree with you that moisture (and the air that carries it) are bigger issues for dye longevity than indoor light. High temperature is also an issue, if it's extreme.

A very good dye supplier, PRO Chemical & Dye, sells Procion MX type dyes in colorless translucent jars. I have not had trouble with ProChem dyes spoiling faster than dyes from other suppliers. However, I usually store my jars of dye in a cardboard box, which does provide protection against light. I think your students' dyes won't be expected to last more than a few months, so there probably won't be a problem as long as they don't store them in direct sunlight. Cobalt-colored plastic would be no worse than unpigmented plastic, so I think the cobalt should be good enough. It certainly is attractive, though it can be more expensive.

Thinking about issues likely to arise with dyes handed out to students: it's important that your students not leave fiber reactive dyes in a car with closed windows on a hot sunny day, because the temperature can easily get high enough to destroy the dyes' reactivity in a single day. You may as well put a label on the jars, or on the package you put the jars into, saying something like "Store at room temperature, out of direct sunlight; do not leave in a hot car."

Cobalt blue glass blocks visible light between 490 and 670 nanometers, and transmits up to 75% of light in the blue and extreme red parts of the spectrum. It blocks the entire middle part of the visible spectrum, including green, yellow, orange, and orangish-red. Amber glass (which seems to me to be dark brown rather than amber in color) transmits about 20% of visible light above 580 nanometers. It blocks most light below 550 nanometers, and essentially all light below 500 nanometers. I don't know how cobalt and amber plastic compare to cobalt and amber glass, in their light absorbance; many plastics transmit more ultraviolet light than plain clear glass does.

Cobalt glass is inferior to amber glass when UV protection is needed, which is why brown bottles protect beer from skunkiness (caused by the effects of ultraviolet light on hops) better than blue ones do. For dyes, protection against UV light is often not as important as protecting against visible light, since the energy the dyes absorb from visible light can damage the dye molecules. Here's a chart showing which wavelengths a number of different Procion MX type dyes absorb (I must have gotten the data for this chart from Olli Niemitalo):

Procion mx dyes spectra

Some of the dyes, such as Turquoise MX-G, have a significant amount of absorbance in the ultraviolet range, which may make them more susceptible to damage from ultraviolet light. It looks as though the red dyes are likely to be well protected by a cobalt blue container.

You're probably already aware of how important it is to avoid breathing dye powder while you are repackaging your dyes. Make sure that your dust mask fits well enough that you don't breathe through gaps at the sides where the mask meets your face. Temporarily turn off fans or air conditioning that create a draft on your work area. Consider cutting holes for your hands in a cardboard box to make a dye mixing box (cover the top with plastic wrap so you can see what you're doing). Remove all food items and food preparation materials from the room, and cover all countertops and tables with plastic or a thick layer of newspapers. It's surprising how easily and quickly a few particles of dye will fly across the room to light on surfaces where you don't want them.

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Friday, April 06, 2012

I mistakenly got a little bleach sprinkled on a few spots—can I fix them with a fabric dye?

Name: Cheryl

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Country or region: Maryland, USA

Message: I have a pair of brown corduroy pants made with 98% cotton/2% elastane fabric. I mistakenly got a little bleach sprinkled on a few spots and wondered if/how I could fix them with a fabric dye. There is not any damage to the fabric except for the discoloration. I would greatly appreciate your help since I can't seem to find an answer anywhere for this. Thank you very much!

Here's an FAQ page answering your question:

"How can I fix the bleach spots on my favorite clothing?"

First, neutralize any remaining bleach by washing the garment (which you've probably done already) and then soak it in Anti-Chlor or ordinary 3% hydrogen peroxide, then wash again. (see "How can I neutralize the damaging effects of chlorine bleach?".)

Second, find the closest color match you can among the fabric markers at your local hobby/crafts/sewing store. If you don't have a local store, check out the wide variety of fabric markers for sale online, such as through Dharma Trading Company. If you use a permanent marker that is not a fabric marker, instead, such as a Sharpie marker, keep the marker on hand to reapply after a few launderings fade the ink.

After using the marker, if the results are not good enough, you can dye your corduroy pants with Procion MX cool water fiber reactive dye, which you will have to order online. Do not use any hot water dye, such as Rit all-purpose dye, on clothing that contains elastane; elastane (also known as spandex or Lycra) is very sensitive to high heat.

Dyeing is almost never enough to cover a bleach spot, because the rest of the fabric gets darker at the same time as the bleached spot. Dyeing and using a fabric marker is a better solution.

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