Why Do White Textiles Turn Gray or Yellow?

In the processing of textile care, one of the most common customer complaints is that white clothes turn gray or yellow. According to the Deutscher Textilreinigungs-Verband e.V. (DTV), this kind of problem often occurs in the washing or wet cleaning services, and the forms are various. In this article, we will analyze the main reasons for linen turning yellow and gray and provide practical prevention measures to help laundry industry practitioners improve their service quality and reduce customer disputes.

Types

On the basis of the scope of influence and causes, the discoloration of white textiles can be classified into the following categories.

Overall grayness/yellowness

The whole piece of clothes changes color evenly and affects both the outer fabric and the lining, or only affects the outer layer.

Partial grayness/yellowness

It only shows in some areas of the clothes, and it often occurs in the areas where stains are not treated properly.

Fibers’ special grayness/yellowness

Some fibers are sensitive to discoloration. ( wool, polyester) They easily change colors due to physical or chemical factors.

Causes and Precautions (Overall Change)

The redeposition of dyes or dirt in the washing water

In the laundry process, the free dyes or dirt particles in the water may reattach to white clothes, causing overall discoloration.

Precautions

• Use detergents with anti-dusting agents to absorb free particles to avoid redeposition.
• Make sure the usage of detergents is enough so as to avoid the decrease of cleaning power due to insufficient dosage.
• If there is a color change, multiple clean water rinses or the usage of dye-affinity products can be helpful for remediation.

Electrostatic adsorption

During the laundry process, static electricity is generated by the friction between clothes. If the dosage of cleaning boosters (such as antistatic agents) is insufficient, dirt and dye particles will be adsorbed on the surface of the clothes.

Precautions

• Regularly inspect the dispensing system of the cleaning booster in the equipment to ensure the accuracy of the dosage.
• It is recommended that the equipment supplierdo the maintenance and check whether the metering pump is working properly every year.

Causes and Precautions (Partial Change)

In the process of partial stain removal, if the processing section is too wet or there is too much residual surfactant, it will form a “dirt magnet dirt”. It adsorbs dyes and dirt in the solvent, causing local discoloration.

Precautions

• After pre-treatment, the treatment area should be appropriately dried to avoid too much water or detergents.
• After using the stain remover, it is suggested to use clean water or neutral solutions to do the rinse to reduce the surfactant residues.
• Water-soluble stains should be gently dried after treatment to prevent penetration and spread.

Discoloration Caused by the Characteristics of Fibers

Loss of fluorescent brighteners

White textiles (especially wool) are often added with fluorescent brighteners to become whiter. When they are exposed to the ultraviolet rays, these brighteners will resolve, which causes the clothes to become gray or yellow gradually.

Precautions

• This kind of color change belongs to the natural aging process and cannot be restored through cleaning.
• It is recommended that customers avoid direct sunlight when storing clothes and regularly change old clothes.

The reaction between synthetic fibers and plasticizers

If synthetic fibers such as polyester and polyamide contact with plastic films (such as PE bags) for a long time, they will have chemical reactions with the plasticizers in the films. This will cause the fluorescent brighteners to lose their effectiveness and make the fabrics gray.

Precautions

• After washing, it should avoid using plastic film wraps clothes for a long time, especially high-end clothes such as wedding dresses and evening gowns.
• It is recommended to store in breathable clothing covers or cotton bags.
• For clothes that are stored for a long time, laundry shops should keep a detailed record of the appearance when receiving the clothes to avoid responsibility disputes.

Color Change Caused by Improper Storage

Showcase

• Natural silks such as wool and silk tend to turn yellow in a closed environment.
• Bedding and other items that are stored under the bed or in a closed space for a long time are prone to mold and insect infestation.

The correct way of storage

• Clothes should be stored in a well-ventilated, dry, and dark environment.
• Avoid using plastic films as a long-term package material.

• Regularly check and record the condition of the clothes that haven’t been used for a long time.

Conclusion and Suggestions

The graying and yellowing problems of white textiles are mostly influenced by the washing process, fiber properties, and storage methods together. Laundry practitioners should take the following measures to reduce the incidence of such problems:

• Choose proper detergents and auxiliaries to make sure the dosage is accurate.
• Control humidity and detergent residue to prevent partial color change.
• Regularly check the condition of the metering system and the application of the cleaning booster.
• Record the condition of the clothes during the receiving inspection and clarify the boundaries of responsibility.
• Offer professional storage advice to extend the lifespan of clothes.

By scientific management and professional operations, the laundry shops can not only reduce complaints from customers but also improve the service quality and customer satisfaction.