by Patricia Harman
Second of three parts
In the last column, we covered some of the problems that may arise as customers use and care for their specialty rugs or wall-to-wall carpeting. Here are several more issues that may arise before or after cleaning carpets.
Color Changes
Dyes are chemical compounds added to fibers to give them color. Sometimes these dyes react with chemicals or gases and color changes may occur.
Fume fading
This is a reaction to gaseous pollutants in the air. It is a gradual change, accelerated by sunlight, heat, high humidity and the presence of acid on the fiber. The most common color changes are blues to pink, greens to yellow, and browns to red. The color change usually starts at the tips of the tufts and progresses toward the backing.
Ozone fading
Caused by ozone gas in the atmosphere, it is also accelerated by high humidity and heat. Ozone is more prevalent around electrical motors, fluorescent lights and during lightning storms. Fibers subjected to ozone fading may lighten, turn white, or change from one color to another as in fume fading.
Some carpet fibers are dyed with indicator dyes that are sensitive to either acid or alkaline chemicals. An alkaline-sensitive dye will change color if exposed to ammonia or deter- gent with a high pH. The color can often be changed back with diluted acetic acid like white vinegar. An acid-sensitive dye will change color when exposed to vinegar or other mild acids with a low pH. The original color often can be restored with diluted ammonia. These color changes may not be permanent and often can be reversed. Other color changes due to strong chemicals are not a result of this “indicator effect” and may not be reversible.
Color changes that become apparent after cleaning are sometimes incorrectly blamed on the cleaner or cleaning process. In many cases, however, the color change is due to the aging of dyes and fibers over time. Cleaning reveals the true color by removing dirt and loosened dyes.
Corn Rowing
Corn rowing appears on carpets before or after cleaning when distinct rows of tufts appear to have fallen over and the tips have become embedded in the carpet pile, usually forming a regular pattern, with every fourth or fifth row bending over as if it were a row of corn. The condition may develop in traffic areas and under doors that scrape the carpet when opened and closed and generally occurs perpendicular to the traffic direction.
In most cases, the overall density is not adequate to support the yarns and keep them upright. If there is too much space between the rows, the tufts may be bent over when they are walked on.
It appears most commonly on carpets made from fine, soft yarns with a fairly high cut pile. Those yarns do not spring back as readily as other carpet yarns made from heavier and denser fibers.
Although cleaning the carpet may bring the problem to light, it is not because of the distorted pile surface. Corn rowing is simply an inherent characteristic of certain carpet constructions. Vacuuming and raking the carpet perpendicular to the traffic pat- terns may help in some cases but in extreme situations, you should contact the manufacturer.