The Repurposing Life

“Bluing” for Brighter Whites

Bluing, laundry blue, dolly blue or washing blue is a household product used to improve the appearance of textiles, especially white fabrics, making for brighter whites. Used during laundering, it adds a trace of blue dye (sometimes Prussian blue, sometimes synthetic ultramarine) to the fabric causing the human eye to see the white of the fabric much brighter.

White fabrics acquire a slight color cast after some use (usually grey or yellow). Since blue and yellow are complementary colors in the subtractive color model of color perception, adding a trace of blue color to the slightly off–white color of these fabrics makes them appear whiter.

Uses for Laundry Blue

Many white textiles are blued during manufacturing, but bluing is not permanent and rinses out over time leaving dingy or yellowed whites. Commercially manufactured laundry detergents use fluorescing agents to similar effect. A commercial bluing product allows the consumer to add the bluing back into the fabric to restore whiteness. Laundry bluing is made of a colloid of ferric ferrocyanide (blue iron salt, also referred to as “Prussian blue“) in water. Bluing has other miscellaneous household uses:

1. Is sometimes used by white–haired elderly people in a blue rinse for their hair.
2. As an ingredient in rock crystal “gardens” (a porous item is placed in a salt solution, the solution then comes out in the form of crystals).
3. To improve the appearance of swimming pool water.
4. In Australia, it was used as a folk remedy to relieve the itching of mosquito and sand fly bites.

The History of Bluing

Blue colorings have been added to rinse water for centuries, first in the form of powder blue or smalt, or using small lumps of indigo and starch, called stone blue. After the invention of synthetic ultramarine and Prussian blue it was manufactured by many companies, including Mrs. Stewart’s Bluing in the United States, and by Reckitt’s Crown Blue in Hull and the Lancashire Ultramarine Company’s Dolly Blue at Backbarrow (a village in the Lake District National Park in England), which was later purchased by Reckitt & Sons. It was popular until the mid–twentieth century in the United Kingdom and the United States, and is still widely used in India and Pakistan. In many places, it has been replaced by bleach for its primary purpose.

Bluing is usually sold in liquid form, but it’s also available as a solid by Reckitt & Sons in the shape of a square block. Solid bluing is sometimes used by hoodoo doctors to provide the blue color needed for “mojo hands” without having to use the toxic compound copper (II) sulfate. Bluing was also used by some Native American tribes to mark their arrows showing tribe ownership.

Brighter Whites

There’s nothing quite as disappointing as when that new set of clean, crisp white sheets starts to yellow. Luckily there’s a secret to keeping whites bright, and that’s blue. Or laundry bluing, to be exact. The reason your linens yellow over time is they were never white to begin with.

Natural (and organic) cotton is off–white, so your snow–white sheets were most likely bleached or dyed with the slightest bit of blue by the manufacturer. Every time you wash your whites, a little of this blue tint is washed away. Dirt and oils further the discoloration, which no amount of bleach can combat. Used for centuries, old–fashioned laundry bluing is the most effective and environmentally friendly way to whiten your whites.

Is Laundry Bluing Safe?

Laundry bluing is an age–old washing practice whereby whites are rinsed with a bit of diluted, nontoxic, biodegradable blue liquid (or powder). The eye perceives the nearly undetectable amount of blue and sees the fabric as whiter. Commercial bluing products are highly concentrated and must be diluted before use to prevent permanent staining and streaking. It is inadvisable to use bluing together with bleach. The best known bluing product is Mrs. Stewart’s Bluing Liquid, made of a fine blue iron powder suspended in water mixed with small amounts of pH balancer and a biocide to prevent the buildup of algae and bacteria. Other brands include Bluette and Reckitt’s Crown Blue.

Adding Blue To a Top Load Washer

Always dilute bluing (it is highly concentrated) in cold water before adding to any type of washer. Never pour it directly into the machine because it can permanently stain fabrics. To whiten whites in a standard or top load HE washer, in the wash cycle, stir ¼ teaspoon liquid bluing into 1 quart water. Use a glass jar to prevent staining plastic containers. Then add the solution to the wash water once the drum is full.

If adding bluing only to the rinse cycle, use ⅛ teaspoon dissolved in 1 quart water. Never use an automatic dispenser for bluing in a top load washer for either the wash or rinse cycle addition because it will stain the dispenser. Bluing can be used with detergent but should never be used with chlorine bleach, fabric softener, or any other laundry product. These other products will cause spotting or staining if used in conjunction with bluing.

Adding Blue To a Front Load Washer

For use in a front load washer, use the same amount of bluing as directed above. If the dispensing drawers on your washer remain unlocked during the cycle, dilute the bluing in 1 to 2 quarts water and add through the dispenser directly into the cycle after it has already filled the drum with water. If the drawers on your front load washer lock as the cycle begins, dilute the bluing as directed on the bottle and then put as much diluted bluing as will fit into the largest available drawer.

Bonus: Bluer Blues

For darker blues, I found Reckitt’s, which is more concentrated, to be most effective. For blue jeans, more bluing can be used. You can use up to 1 teaspoon per quart of water depending upon how dark you want your jeans to be. Follow the directions for your washer or use a porcelain sink or metal bucket for the process. The bluing will stain plastic containers and fiberglass sinks permanently.

Pitfalls to Avoid

One note of caution, extremely discolored linens will not come out bright white after one rinse. Avoid the temptation to add more laundry bluing than is recommended. This will result in either blue spotting or grayish whites. If this happens, do not use bleach in an attempt to correct the problem, as this will just set in the blue dye stains permanently. Instead, you can remove the excess blue by submerging the fabric in a 2:1 ratio mix of water and ammonia.

Note: Be sure to do so in a ventilated room and, again, do not use bleach, as mixing ammonia and bleach is toxic.

Removing Bluing Stains

If you used a bit too much blue, or skipped some steps in using it correctly, here’s how to remove the bluing stains from laundry items:

1. You’ll need a non–metal container that can be covered tightly (a five–gallon bucket with a good, tight lid or a plastic bag with a twist tie).
2. Place the stained clothes in the container.
3. Mix a solution of ½ cup household ammonia to 1 quart cold water.
4. Make enough solution to completely submerge the stained clothing.
5. Make the container as airtight as possible to keep the fumes in.
6. Ammonia evaporates very quickly and ammonia is the only substance that will remove the excess blue.
7. Soak for 24 hours. 
8. If the stain is not gone in 24 hours, mix a fresh ammonia solution and repeat the process.
9. Finally, wash the clothing on a regular wash cycle with detergent only.
10. If you have already attempted to remove the excess bluing with chlorine bleach, use a solution of 1 cup household ammonia to 1 quart cold water and soak, covered tightly for 48–72 hours.
11. You may need to perform this process 2 to 3 times, washing with detergent following each process.

Worth the Effort

I found that laundry bluing was effective at maintaining my whites and was well worth the effort, especially when you consider that it’s a better environmental alternative to bleach. If you missed the final rinse cycle, set a timer or stay by the washer while doing other household tasks.

Sources:
DIY: How to Whiten Your Sheets with Laundry Bluing
https://www.remodelista.com/posts/whiten-sheets-bluing-powder/
Justine Hand April 3, 2017
Laundry Bluing and How to Use Bluing
https://www.thespruce.com/how-to-use-laundry-bluing-2146367
Written by Mary Marlowe Leverette, Updated 12/30/20
https://en.wikipedia.org/wiki/Bluing_(fabric)