Lifestyle
／
2022.07.04
I noticed that my towels were discolored. What should I do? – Blackening Edition –
We have received your concerns about discoloration of your laundry.
Next, we will answer your questions about dark spots.
-Orange, pink, yellowing edition- Click here >
My towels are turning black! Why?
I often hear from various sources that towels gradually become darker after repeated washing, but after researching, I found that there seem to be several causes for the darkening.
The solutions vary depending on the cause, so we'll introduce some typical examples.
① Accumulation of fine particles
When you use a towel for a long time, tiny dirt particles (particles) such as pigments and dust from clothes that are washed together with it are absorbed into the towel along with the wash water and gradually build up, causing it to become dark.
Towels not only absorb many times more water than clothing, but their fabric acts like a filter, trapping dirt in the water during the wash.
Drying clothes near a busy road or in a dusty area can also make them more susceptible to picking up tiny particles floating in the air.
The darkening in this case occurs due to the adsorption of dirt in the water and fine particles in the air, and tends to occur all over the towel.
↳ How to solve and prevent dark spots caused by particulate dirt
If the cause is dye that has dissolved from other clothing, it can be removed by soaking the item in water with a small amount of powdered oxygen bleach dissolved in it.
However, if there are fine dirt particles mixed in, the dirt has to be pushed out from deep within the fibers, so it will be difficult to remove unless you repeatedly wash the towel by vigorously rubbing and scrubbing it in water.
The best prevention is to prevent dirt from building up.
Washing thoroughly with plenty of water and rinsing thoroughly will help prevent dirt from building up.
↳ An unexpected cause! Charcoal body soap
Binchotan charcoal and bamboo charcoal are similar to fine particles, so if body soap or shampoo gets stuck to laundry and mixes with the wash water, they can cause blackening.
② Mold growth
Just like yellowing, frequently used parts such as the center of a bath towel or the top and bottom edges of a face towel may appear slightly darker because of mold growing in the fabric of the towel.
The pile surface dries relatively quickly and is less susceptible to mold, but the base fabric takes longer to dry and is prone to stains, so if you're not careful in warm seasons, mold can quickly grow.
Mold has a strong root in the fibers, so once it appears it will not go away even if you sterilize it.
↳ How to solve and prevent dark spots caused by mold
If it is in the early stages, it may be possible to remove it by soaking the item in water or hot water with a small amount of powdered oxygen bleach dissolved in it, or by boiling it with baking soda, but usually it can only be removed by using chlorine bleach.
If you have plain white towels, you can restore them to their pure white state with chlorine bleach, but if you have colored or patterned towels, unfortunately there is nothing you can do.
The key is to wash and dry it immediately after use.
Mold cannot grow without the nutrients of dirt and moisture, so be careful not to leave the area dirty or damp.
3. Repeated use of fabric softener
If you use fabric softener repeatedly, the towel may begin to take on a darker color.
This isn't because the fabric softener itself is discoloring the towel, but because using fabric softener makes the towel more susceptible to attracting microscopic dirt and pigments.
Because fabric softeners have positive electrical properties, they tend to attract fine dirt particles and pigments, which have negative electrical properties, making them more susceptible to darkening due to the accumulation of fine dirt particles, as explained in <① Accumulation of fine dirt particles>.
Also, although it does not cause blackening, it has the property of strongly attracting the pigments contained in tea, coffee, etc., making tea and coffee stains difficult to remove.
Furthermore, repeated use of fabric softener will not only cause the fabric to turn black, but it will also stop absorbing water.
↳ How to prevent darkening caused by fabric softener
Fabric softeners are used to restore the lubricity of fabric fibers that have become dull.
It depends on the material of the laundry and how you wash it, but with modern fabric softeners, the ingredients remain for 2-3 washes after one use, so you don't necessarily need to use it every time. When you notice that the fabric feels stiff or has lost its smoothness, try using it just once to start with.
In the article "Powder? Liquid? Delicate laundry? How to choose laundry detergent and how to use bleach and fabric softener properly", we also introduce the correct way to use fabric softener. Please take a look at this article as well.
Don't use fabric softener every time >
④ Use water-saving washing machines
In the case of water-saving washing machines such as drum-type washing machines, even a slight change in the conditions can easily cause both the washing and rinsing processes to be insufficient, which can lead to dirt not being completely removed, causing laundry to become blackened.
However, it's not the washing machine itself that's at fault; the main cause is relying too much on the capabilities of the washing machine and detergent.
If you try to wash a lot at once by putting too much laundry in the washing machine, or if you don't use the correct amount of detergent or fabric softener, the washing efficiency will naturally decrease and the dirt will not come off as well.
In particular, with drum-type washing machines, many models do not allow you to change conditions such as the amount of water or the number of rinses, so it is important to carefully adjust the amount of laundry washed at one time depending on the type of laundry and its level of dirt, and to select a course that suits the type of laundry and its level of dirt.
↳ How to prevent blackening with water-saving washing machines
Water-saving washing machines tend to leave stains on clothes if they are not used under the best conditions, so the key is to load a small amount of laundry and choose a cycle that washes as thoroughly as possible.
This is a little trick, but especially when washing towels, it is recommended to soak the laundry in water first to make it heavier before putting it in (= trick the washing machine).
Attractive claims about washing machines and detergents are basically based on the "best conditions," so they may not live up to your expectations depending on the situation.
For example, the maximum capacity of a washing machine is a theoretical limit, and in reality manufacturers recommend washing at around 70% of the maximum capacity, and "one rinse" actually means "one rinse is OK if the clothes are only slightly dirty."
It would be ideal not to be fooled by slogans such as "water-saving" or "energy-saving," but to determine the amount of laundry that can be washed efficiently based on the state of dirt and the type of washing machine you are using, and to use the washing machine and detergent with a certain level of understanding.
It is important to wash clothes according to the situation.
Bonus: Laundry turns brown after hanging out to dry! Why?
This type of discoloration does not occur often with towels, but it can sometimes occur with clothing made from synthetic fibers or synthetic resin parts.
Nitrogen oxide gas, which is produced when something is burned, reacts with antioxidants contained in synthetic resins and other materials, causing brown or yellow discoloration.
Cotton towels do not contain antioxidants, but they may absorb antioxidants that evaporate from surrounding synthetic resins and other substances.
Moisture is particularly likely to absorb gases, so for example, if a wet towel is left in a synthetic resin laundry basket or laundry bag for a long period of time, the towel can absorb the antioxidants released from the basket and nitric oxide gas in the air, causing it to discolor.
We often hear stories of canvas sneakers with the rubber and glue turning brown after washing them, or of clothes discoloring after eating hot pot or grilling meat indoors, but these are based on the same principle.
-Orange, pink, yellowing edition- Click here >