Can You Bleach Polyester?

One of the more beautiful things that are happening right now online is all these youngsters who are buying second-hand clothing and giving the garments a fresh makeover. Instead of buying some cheap rags from a fast-fashion company, they re-fashion these old garments that would otherwise end up in the landfill.

I’ve seen people would find a garment they like in a color or print they didn’t care for. Then, they would bleach the garment to give it a new paint job. It’s all nice and dandy when working with cotton and linen, but what would happen to polyester or poly-blends? Well, today we are going to look into that. You’ll learn everything about bleaching polyester, plus what are your options if you want to dye it afterwards.

Is it OK to Bleach Polyester?

It is, but you have to be careful. The problem is that the dyes used on polyester are bleach-resistant, but the fibers are not. If you leave the fabric in bleach for too long, it will become soup. Not literally, but the garment will be unwearable.

You have many options if you want to remove stains that don’t include bleach. But if you are looking to lighten fabric, make sure to pick the right product and follow the instructions properly.

Polyester vs Poly-Blend

Cotton or other fiber mixed with some polyester is less finicky than 100% polyester, but you should still be careful. It’s always better to treat a fabric that has at least some synthetic fibers as if it were 100% synthetic.

Always consult the care label. Plus, a quick note, bleaching a blended fabric to remove stains doesn’t always work. It’s better to pick a different method even if the bleach manufacturer and the care label say it’s should be okay. 

Polyester With Nylon, Spandex, or Lycra

Never bleach anything with nylon, spandex, or lycra, ever. They will literally melt, and the word literally is not misused here at all.

If you have a stain that you need to get rid of, try something gentler like alcohol. But if you want to bleach a swimsuit so you can dye it a different color, forget about it. Buy a white swimsuit and play with that to your heart’s content.

How Long Does It Take to Bleach Polyester?

Depends on the strength of the bleach solution and the product you’re using. Chlorine bleach works faster, but you also have to constantly monitor what’s happening to the fabric. Oxygen bleach will take a lot longer, at least 8 hours or more.

Can You Use Regular Bleach?

You can, but don’t. Chlorine bleach may turn cotton and linen whiter than the teeth of a Californian executive, but it’s not very effective nor gentle to polyester. First, it’s very likely to cause the fibers to start breaking down. And second, even if you manage to avoid ruining the garment, you’ll soon find out that chlorine bleach turns polyester yellow, not white.

You can always test a small piece and see how bad it will get, but it’s safer to pick an oxygen-based bleach, to begin with. 

How to Bleach Polyester

As mentioned above, each product will come with clear instructions on how to use it on polyester. But here is a quick guide of what to do and what to expect in general.

How to Bleach a Stain on Polyester

You can remove stains from polyester without bleach. Hydrogen peroxide will work on organic stains (blood, food, etc), while alcohol is great for ink-based stains.

If you need to brighten your whites, or if alcohol and hydrogen peroxide are not working out, it’s better to go for an oxygen-based bleach. It also has hydrogen in it, but also a bunch of other chemicals to make it more effective.

How to Bleach Polyester Fabric

If you must use chlorine bleach, dissolve about a 1/4 of a cup per gallon of water. If you’re using oxygen bleach, follow the directions at the back of the box. 

When using chlorine bleach, soak the fabric for 5 minutes at a time. If you’re using oxygen bleach, leave it to soak on its own and check for progress after a couple of hours.

Once the soaking is done. rinse out the chemicals under running water then wash the garment straight away. With oxygen bleach, you can repeat the process if you find that the fabric is not white enough when it dries. 

How to Care for Bleached Polyester?

You should always wash your clothes in cold water. This is the best way to preserve the color and the integrity of the fibers. It will also make prints and appliques last longer. You probably have to start buying a different detergent since you will need one that works in lower temperatures, but it’s worth the hassle. This little switch will not only lower your electricity bill each month, but it may double the lifespan of all your clothes (which will save you money as well).

But even if you don’t want to follow this advice, you will have to start washing bleached polyester in cold water. Bleaching, as in lightening the fabric, will cause damage to the fibers. The hot water and twisting in the washing machine will stretch them out or even cause breakage. Avoid heat and tumble dry only, and consider using garment bags to further protect the fabric.

Can You Brighten Polyester Whites Without Bleach?

Yes, you have a few options that you can try first. Adding some lemon juice or borax with your laundry may work. You can also purchase laundry bluing agents that work similarly to purple shampoo hair and keep yellowish tints at bay.

Will Hydrogen Peroxide Bleach Polyester?

Hydrogen peroxide is a safer option for removing stains polyester, at least when compared to chlorine bleach. If you use a mild concentration, it should not cause discoloration. But if you go even a few percent up, it will leave yellowish stains on the fabric.

OxyClean and other oxygen stain removal products are based on hydrogen peroxide. They are usually safe for use on polyester, just check the label to be sure.

If you want to try pure hydrogen peroxide, stick to 3%. You should be ready to put the garment into the wash right after treating the stain to minimize any chance of discoloration. Wash the garment preferably in cold water with an appropriate detergent that works in colder temperatures. If you don’t have any on hand, go for a lukewarm cycle or the maximum temperature noted on the care label.

Should You Use Bleach to Remove Stains from White Polyester in the Wash?

You can use diluted bleach to remove stains from polyester, but it’s not recommended. It’s better to find an alternative stain removing solution.

But what you should never particularly do is treat white polyester as regular cotton and linen whites. Most of the time people use bleach on their whites is during the wash on the hot water cycle. Most washing machines have settings and compartments that allow you to add bleach to this cycle. It’s meant for things that get stained easily and/or need sanitizing like kitchen towels or reusable diapers.

Though it should be okay to use diluted bleach, what will not work out that way is the hot portion of the hot water cycle. Remember, polyester is essentially very fine and thin plastic, so that means it will melt at those temperatures (at least 130 degrees but easily up to 190 degrees Fahrenheit).

Cotton-blends and other fabrics that tend to contain 15% or less polyester will fare slightly better. However, they will also be completely ruined after only a couple of washes.

How to Dye Polyester After Bleaching

Okay, here is where things get fuzzy, and not in a fun way. You can’t use regular dyes you would use on cotton and those special dyes need very high temperatures for processing. “Virgin” polyester can handle this process, but the same cannot be said with the bleached fabric. Some damage always happens when you bleach polyester, and exposing it to high heat will damage it more.

The safest thing to do is to curb your ambitions and aim to lighten the fabric just enough that the original color has little or no impact on the new one. Then come in with deeper and richer hues, instead of shooting for gentle pastels. This is the best combo to prevent your garment from looking like chewed-up gum.

Now, let’s talk about dyes. If you are working with a cotton blend with 20% or less polyester, you should be able to use regular dyes that work in the washing machine. However, those dyes are water-based and will not work on poly fibers. Expect that the color will not come out as vibrant as if you were to use it on a 100% cotton fabric.

The types of dyes that we need for anything that has 50% or more polyester are called disperse dyes. They are actually tiny powder particles that are not dissolved but dispersed in a liquid. Depending on the brand, they will need different temperatures to work, but it’s usually about 200 degrees Fahrenheit. Also, each brand has different time recommendations, but they will all require you to set up a dye bath and “cook” the fabric before rinsing it out.

Keep in mind that this process usually uses a lot of boiling water and that you should be careful and take every measurement of precaution not to injure yourself. Also, always read the manufacturer’s instructions and warnings properly, and follow them to the letter.