Answer: There are many ways that color loss can occur on any given type of fabric and color. The following are the main reasons for color loss that may occur during everyday use.
LIGHT FADING Many consumers are not aware that dyes can fade if exposed to light, either sunlight or artificial light. This process is called photodegradation and occurs when oxygen and sunlight combine on a surface. The result can be visibly lighter areas and weakened fibers. With this type of color loss, fading is generally apparent on only one side of the fabric. The reverse side is usually unaffected unless the degradation has occurred over an extended period of time. Certain dyes, such as blues, violets, or greens, are more prone to this type of fading than others.
FUME FADING Fume fading (gas fading) develops when air comes into contact with heated surfaces and forms nitrogen oxide gases. These gases then react with certain dyes, usually those found on acetate and nylon, and cause them to change color (usually blue to red). Fume fading usually occurs on both sides of the fabric.
WATER SENSITIVITY Some dyes, such as pink, lavender, and red, can undergo color reactions (usually red to blue) from contact with water or any water-bearing substance, including perspiration. If this color reaction is noted soon after it happens, it can often be reversed by cleaning it. However, in many cases, these dyes are so sensitive that restoration is not possible. Obvious signs of color loss due to water are lighter areas with pronounced edges when the fabric becomes drenched with water. Although this type of color loss is rare, it is more common among dyed fabrics that are not meant to be taken outside or otherwise prone to getting wet such as fabrics used for household decorations.
ACID/ALKALINE SENSITIVITY Some dyes will exhibit a color change when exposed to an acidic or alkaline substance. Contact with fruit juice, beverages, foodstuffs, and other acidic substances can cause blue dyes to turn red; contact with perspiration, household chemicals, toiletries, and other alkaline solutions can turn blue or green dyes yellow. Alkalies can also decompose fluorescent brighteners on white fabrics, causing them to discolor. If treated immediately, most acid/alkaline color reactions can be neutralized and corrected.
ALCOHOL Contact with alcohol can dissolve certain dyes, resulting in permanent color loss. This is especially common on dyes used on acetate and silk. This is frequently caused by spilled drinks but can also be caused by anything containing enough alcohol. The alcohol content of most colognes and perfumes is capable of causing this reaction.
BLEACH Consumers are often not aware of the harmful effects home cleansers, hair products, floor scouring products, disinfectants, and other agents can have on their clothes. Some dyes are extremely sensitive to bleach, and even mildly concentrated bleaches such as chlorine can cause immediate, permanent color loss.