[h=2]I know Ofer has been having some trouble with this type of stain as well, so I dug into my secret stash of knowledge and pulled these out:
There is an increasing number of complaints about color loss, mysterious stains and damage occurring on carpet, rugs and upholstery. These can be due to bleaching and color loss of the dyes. The rise in occurrence of bleach damage parallels the popularity of consumer products containing strong oxygen-type bleaches. These products are sold to consumers for spot and stain removal. They carry a trade name akin to “oxy-“ or “oxi-“ something. This prefix connotes an oxygen bleach (and oxidizing agent) as the main ingredient, by contrast with the more familiar chlorine bleach.
There are several causes that can contribute to fiber damage and dye loss, which unfortunately are permanent when they occur. First is the lack of care and attention by the consumer or user to pretest the product. But all product directions prescribe that it must first be pretested in an inconspicuous location. Many consumers avoid this step, although it’s critical in determining if the dyestuff is sensitive to color change or loss of color from the oxi-type bleach.
A second cause of latent bleach stains is using these bleach products without proper mixing or dilution as required. Recommended dilutions are low, e.g. 1/4 tablespoon per 16 ounces of solution. The adage “if it works, then more is better” is never safe when using bleach! Overuse can indeed result in permanent color loss. Third is the product’s use on upholstery, bedding or textiles instead of carpet and rugs. When used on carpet and rug fibers, the solution might be safer. But on upholstery, there is an even greater risk of color change or dye bleeding. Directions often specify rinsing out these stain removers after use. We know however that rinsing is not always done as required. In addition most bleach-containing products state that they should not be used on wool, wool blends, silk, leather or non-washable items.
The oxi- or oxy-type bleaching products for stain removal may contain sodium perborate, sodium percarbonate or hydrogen peroxide. There is also color loss and bleach damage that can result from using benzoyl peroxide acne medication and cosmetics. These products, when used in very dilute form, might be color-safe on most textiles. But if used improperly or at higher concentration they are capable of damaging textile dyes, resulting in a permanently bleached-out area of color change or color loss.
Cleaners and restorers are often asked about, or improperly blamed for, these mysterious bleach stains. Yet the latent bleaching and damage was likely present before, or the color loss had already begun. Such color changes can be less obvious or obscured by dirt and soils prior to cleaning, only to be revealed after a thorough cleaning.
© 1999 Association of Specialists in Cleaning and Restoration, Inc., Millersville, MD. All rights reserved.
Unusual Spots and Stains - Michael Hilton
[/h]Carpet yellowing - Most yellowing can be eradicated using an acid solution. Acetic acid (white vinegar), citric acid, or tartaric acid can be effective in eliminating some yellowing complaints. A solution of one part white vinegar and one part water is recommended for consumer use.
Optical brighteners - Select a spot removal (carpet stain removal) solution that does not contain optical brighteners. Optical brighteners are actually fluorescent dyes that brighten the color of the fiber. However, ultraviolet light from the sun may cause these dyes to exhibit a lavender cast in areas where the solution has been used. These dyes can eventually oxidize causing a yellow discoloration or color fading of the fiber.
Bleaching agents - Many household cleaning products contain bleaching agents that attack the dyes in most residential carpet. Care should be used in selecting a home carpet cleaning product for use as a spot remover on carpet fibers. Bleaches actually destroy the dye leaving a white or yellow discoloration. In large areas of damage, it may be necessary to remove the area of damaged carpet and reinsert an undamaged portion of carpet taken from an inconspicuous area. Some carpet cleaners have the knowledge to re-dye these damaged areas.
Acids - Some toilet bowl cleaners contain hydrochloric acid that dissolves carpet fibers, as well as coloring agents that can dye carpet fibers. Tile grout cleaners contain phosphoric acid and can damage carpet fibers and dyes. Most acids should be neutralized with an alkaline rinse solution.
Acne medications - One of the most common chemical stains that can occur in the home is caused by benzoyl peroxide used in most acne medications. Benzoyl peroxide is a very strong oxidizing agent capable of destroying most dyestuffs used on carpet. Because of the slow reaction time, this chemical is classified as a latent intruder. In many cases the chemical will remain on the carpet fibers for months before activation by moisture or humidity. Benzoyl peroxide can be transferred through direct contact of the skin or through the shedding of skin scales containing benzoyl peroxide. As the chemical reaction continues, the center of the affected area may be bleached white with a pink or orange halo around the outer edges of the affected area.
Filtration Soiling - One of the most common carpet stain questions, soiling around the out edges of carpet and along the walls, isn't actually a stain at all. This soiling or graying is actually the deposition of soil created by the heating ventilation and air conditioning (HVAC system.)
Insecticides - Many insecticides approved for indoor use can cause color changes in carpet. Insecticides should never be applied directly to carpet fiber unless specified. Most chemicals should be applied to walls and baseboards only. Many insecticides that are recommended for use on carpet may damage carpet color. Some insecticides may attack the red dyes used in beige carpet. This leaves the blue and yellow dyes, which together form green colorations.
Plant foods - Many plant foods contain oxidizing agents that attack dyestuffs leaving green, yellow, or brown discolorations. These stains typically occur near the backing material and migrate upward.
Strong alkalis - Any chemical with high alkalinity can cause permanent damage to carpet fiber. Some carpet cleaning solutions with high alkalinity such as laundry detergents may cause yellowing. Stronger alkalis such as drain cleaners and oven cleaners may cause permanent bleaching.
Pet urine - Pet urine stains and the resulting odor is the most common consumer carpet inquiry. Stains may appear yellow or brown and odors may linger long after the stain has been removed. Not all urine stains can be easily removed. The most effective treatment is the Fabrisan/Odosolv Spot Lifter.
Mildew Removers - Most products that make a kill claim or suggest they kill mold and mildew provide a potential for causing permanent carpet discoloration. Many of these products contain oxidizing bleaches that can permanently remove carpet color.
Shampoos - many colored hair shampoos (especially blue and green dandruff shampoos) may add color to your carpet and cause a discolored area.
Toilet Bowl Cleaners - The tidy bowl guy sometimes finds his way out of the toilet bowl and onto surrounding carpeted surfaces. These blue cleaners can sometimes permanently discolor carpet. Sometimes the spill can be removed if persistence is exercised while the spill remains wet, but once the spill dries, the spill may require a professional. The professional may use a reducing bleach solution, but there are never any guarantees.
Acne medications - Many acne medications contain benzoyl peroxide an oxidizer. In inspecting acne medication complaints, I have rarely seen a consumer that would admit that their teenager cause the problem. In some case, I have found perfect handprints. These medications do not rinse freely and can be left on the hands of the teenager (or adult). Once the oxidizer is applied to the carpet, it may take months to appear. The oxidizer gradually removes moisture from the air and color slowly fades. The center of these spots may be devoid of color while the edges may have a pinkish halo.
About the Author
Michael Hilton was the original creator of Carpet Buyers Handbook. Having owned and operated a carpet wholesale company, Hilton has a vast knowledge about all-things carpet related as well as other types of flooring.
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