Polyester and Cotton

I recently got a question on my review of the Tulip tie-dye kit as to why everyone recommends 100% cotton items for tie-dyeing.

The reason for the 100% rule (down to 80% cotton usually works fine too) is that polyester fibers are, when you get right down to it, plastic. Think about the polyester fleece now made from recycled soda bottles (such as that in Patagonia products), and you have the idea. The Procion dyes used in the Tulip kits (as well as Dharma and Jaquard) wash right off of plastic (gloves, table covers, etc.). So that's what happens with your shirts. If you look closely at the cotton/poly, you should be able to see white fibers after washing the excess dye out. That's the polyester.

Here are some examples. The following picture shows a rag I use to clean up my dye spills (thus the mottled colors). It's a piece of thermal underwear that is a cotton/poly blend.


Here is a closeup of the same piece. The white threads are the polyester. The cotton has taken the dye.


It's almost impossible to find pure cotton socks, since synthetics such as polyester and nylon help the socks wear much better. Also, any elastic used in the socks will be non-cotton itself and probably covered in polyester or nylon. The trick is to find socks that hide the polyester or other synthetics as well as possible. Usually you will have to try dyeing a pair to see how they work, since it's impossible to tell the difference when the socks are still white.

This sock shows a lot of synthetic content in the foot, but less in the folded-down cuff. If you like the heathery mismatched look, it's fine.


This sock dyes quite well. The foot is only a little heathery, and the outside of the slouch cuff hardly shows white at all.


Here is the closeup. Note that the elastic around the cuff is fairly well hidden on the inside. You can see the white flecks in the foot area.


Here are two turtlenecks I dyed. The one on the left is 100% cotton, and the one on the right is 60%cotton/40%polyester. The turquoise and navy shades are supposed to be the same in both shirts.


You can't quite see the white threads here because they are so fine and well interspersed with the cotton, but it's definitely the polyester making this shirt so faded looking.


This is where the turtleneck attaches to the poly-blend shirt. The turtleneck is a somewhat different blend from the shirt body, and it contains 10% spandex. It is also a different weight and knit from the body. Note that the two different blues are the different fabrics' reaction to the same dye color. There is no way I could have intentionally dyed these different shades with such a clean line between them!


The following is the 100% cotton shirt. Note that in both this and the previous shirts, the stitching is pure white. It's polyester. For most shirts, nobody would notice, or if they did, they would think that it's intentional contrast stitching. However, this is why Dharma notes on almost all of their garment blanks whether they are stitched with polyester thread (they often say "Not cotton thread"). For some garments, visible white stitching would be an unwelcome surprise.


Dyeing Polyester

Dyeing polyester requires different types of colorants, since most fabric dyes just wash off the fiber. Dharma offers one type of dye for polyester but it requires hot water, and it usually needs to be simmered on the stove. Since I'm more of a natural fiber fan, and I'm too lazy to use anything other than the cold-water Procion dyes, I haven't tried it myself.

Respect the Blends

Keep in mind that you can get interesting effects using the cotton/poly blend fabrics, such as the patterned effect on the thermal underwear knit. I've seen tops in stores recently where the fabric is knit in stripes or patterns of cotton followed by polyester blend, providing a very cool arrangement of strong and pale colors. Also, if you like pale pastels, blended fabrics give you an easy way to do it.

Review of Tulip Tie-Dye Kit

At one point I was planning to teach a regularly-scheduled tie-dye course for a local craft store. That didn't work out, but the plan was that I was going to have to use the products they carried in the store. You know, teach classes at the store to encourage students to buy the store's products (dyes, white stuff) . Sounds good, but the store doesn't carry the products I usually use! So some trials were in order to see if I could come up with a class worth teaching using their available products. The short answer is "yes, but..."

The Adventure Begins

The store carries a line of Tulip "One-Step Tie-Dye Kit" brand kits made by Duncan. It comes in several different groups of colors , such as "Classic" (yellow, fuchsia, turquoise), "Vibrant", and so on. I used the Classic colors.

The kit consists of three teeny little plastic squirt bottles, each containing about half an inch of dye powder, a pair of really cheap plastic gloves that appear to be made of plastic wrap, a small handful of rubber bands (maybe a dozen), and an instruction sheet (which contains English, Spanish, and French instructions, so only about 1/4 of the glossy page is useful to me).

Nowhere on the package or instruction sheet could I find any mention of what type of dye the kit contains, but the website says it's Procion dye. There is no soda ash packet in the box, so I assume the soda ash fixer is mixed into the dye powder in the bottles. The extra little paper notice tucked into the box says to make sure to use the dye within 30 minutes of adding water (the glossy instruction sheet says 45), so I take that as confirmation that the soda ash is in the bottles with the dye. Normally I would have the soda ash separate, because then you don't have to use all the dye right away. But at least it's the right kind of dye!

Next comes the white stuff. I'm used to getting a wide variety of cotton things from Dharma, but the challenge is to get stuff from the craft store! Well, they have a line of t-shirts from Jerzees. The shirts are fairly cheap, about $2.50 on special sale, but they are made of 50% cotton and 50% polyester. Wait, I find a 100% cotton shirt mixed in with the others, also from Jerzees. But it's from a different part of the rack, and costs about 7 dollars! Ouch. I get one of those and a few of the cotton/poly blend shirts.

Now the Work Starts

I washed and dried all but one of the shirts in detergent with no softener or dryer sheets, as is my usual habit. I wanted to dye one shirt (a cotton/poly shirt) unwashed to see if that made any difference. I folded and banded all of the shirts (dry), to make an X, two diamonds, and a swirl.

I added the water to the 3 bottles as directed and shook them up. I then took about half an inch of dye from each of those bottles and used it to make up three more bottles (same sized bottles, which I already had around) of those colors, diluted with more water. This second set of diluted dyes is not part of the kit instructions, but I figured that since I tend to go through a lot of dye I should stretch it as best as I could.

I usually dye pieces while they are wet from being soaked in soda ash. In this case, the shirts were all completely dry, and the dye had a tendency to bead up and roll somewhere I didn't want it. I had to jam the tip of the bottle onto the fabric to get the dye to stay put. That's not so much because of the particular kit so much as it's the particular process with the soda ash mixed into the dyes. Next time I'd try it with damp shirts from the washer.

Results

I managed to dye four t-shirts with the six little bottles of dye, and I had enough left over to dye a pair of socks (okay, so those weren't from the craft store!). Here they are:


Can you spot the cotton shirt? It's the X. The colors are definitely more vibrant and "popping" on the cotton shirt than they are on the cotton/poly shirts.

[Lacey, tie-dye hound that she is, can't resist pointing out the cotton shirt... she sees me laying out tie-dye on a blanket to take pictures, and she's right there in the middle, posing!]

For this X, I folded the shirt in quarters, then accordion pleated diagonally from the center to the outer corners. I used the full-strength dyes in sections on one edge of the pleats, and the diluted dyes in the same sections on the edges of the other side. That's what gives it the dark-light-dark effect, which is especially noticeable in the turquoise stripes.

It's hard to see in these photos, but the dyes spread differently on the cotton than they did on the cotton/poly. Remember that I applied the dye to dry, washed t-shirts. On the cotton, the dye tended to stop spreading and not blend quite so much. On the cotton/poly, the dyes tended to spread out more and blend more, giving a more "smeared" effect as seen in the diamond shirt below. Close up, the cotton/poly also has a more "heathered" appearance because the white polyester fibers don't pick up the dye. This diamond shirt is the one cotton/poly shirt that I did not wash before dyeing.


The diamond pattern is folded the same way as the X, except the pleats are folded on the other diagonal, from the underarm to the neck.

Here is the other diamond shirt (cotton/poly). It looks more faded mostly because the majority of the shirt (the outer sections) were dyed with the diluted dyes. That's the opposite of what I did with the first diamond, which is more faded in the middle.


The only difference I can see between the pre-washed and unwashed cotton/poly shirts is that the pre-washed shirt is pilling more than the unwashed shirt, having been through the washer an extra time. That's one reason I usually avoid cotton/poly blend shirts--they pill like crazy, so they just don't feel as good to wear.

Here is the swirl shirt (cotton/poly). Notice again how the colors sort of smear together. I like the visible difference between the full-strength and diluted yellows here.


Comments

I liked the fact that the water-adding instructions were printed right on the bottles. Once I had gloves on, it was hard to handle the instruction sheet.

The instruction sheet provided lots of good ideas, but not enough "meat" on how to actually do some of those ideas. A lot of the space was taken up with the Spanish and French versions, so there wasn't much space left in any of the languages for more in-depth instructions.


Since there is no measuring and almost no mixing for the dyes, it's really easy to use. And because the soda ash is right in with the dye, you don't need a separate bucket or container for soaking the shirts before dyeing (and no dripping mess from moving the wet shirts around).

Like many craft kits, the actual quantity of materials (dye) provided is pretty limited, so it's not good for more than one or two people (and definitely not the hardcore "let's-dye-the-couch" types that I hang out with!). At about $10 for the three-color Classic kit I got, this is definitely not the most cost-effective way to do tie-dye (see my blog entry on resources). The box says the kit is good for "up to 8 projects", but I didn't even get close, even after diluting some of the dye.

These tie-dye kits are marketed towards young teenage girls, as shown by the picture on the boxes. For one or two girls doing a kit session on an otherwise dull afternoon, this is a great kit to have on hand (along with a couple of cotton t-shirts). It's also good for a first try at tie-dye on your own. For anything more than that, get a bigger tie-dye kit from Dharma or put together your own.