Correcting Browning & Yellowing
Most browning will occur in older carpets. The factors that cause browning are not as prevalent in new carpeting, and the cellulosic materials have not had the time and abuse that will begin to break them down. Browning might also be described as color change. There are many factors that cause colour change on carpet after cleaning. The Four main factors that contribute to browning are: 1. Over wetting (technician error), 2. High Alkalinity, 3. Cellulosic fibers (true cellulosic browning), and 4. Extended drying time.
Carpets that are constructed of cellulosic fibers such as cotton and acrylics, as well as light coloured wools should be cleaned with neutral chemicals and soured (acid solution such as Fab-Set) after the cleaning process. In flooded or very damp situations, moisture coming up from the damp floor can create browning and make that which is present more difficult to remove. It is important to know the cause of the browning.