I just got off the phone with a carpet dealer who had a question about yellowing. He stated that he had installed a polypropylene berber in a home last June that was down about 6 months. That carpet he replaced because the consumer dropped a log on it and burned a hole in it. The carpet that replaced it was the exact same thing, from the same manufacturer. The problem is that this carpet turned yellow everywhere but under the furniture. It also did it on the stairs to the basement to some extent. When he tested with white vinegar to see if an acid wash would neutralize the condition, there was no change. Now his question is, what is this and why is it not responding as it should?

This is a bit challenging because the previous carpet showed no signs of a problem and during the time both carpets would have been in, they would have been subject to similar types of conditions. That is the heating system would have been on and so would the air conditioner and natural ambient air present. The pad is a rebond so there could be some BHT influence, even though there has been efforts to stop or limit the use of BHT, it could have still found its way into the pad. The yellow is not under the furniture nor other covered areas. This has to tell us that it could be BHT, but it would be catalysted by oxides of nitrogen, which could be contributing to the yellowing. The other issue could be yarn lubricant. This is an oily surfactant based lubricant used on polypropylene during manufacture. It is supposed to flash off in the finishing range but doesn’t always. If there is a residue, which can be easily determined with a simple test, it may also contribute to the yellowing. At any rate there are enough factors that could contribute to the cause of this problem. If a treatment with a more potent yellowing neutralizer, such as citric acid, doesn’t work then the carpet will have to be replaced. At issue here is also the fact that the first carpet, supposedly exactly the same, showed no signs of a problem and the second one did. If you should have a situation like this you have to sift through all of the factors until you find the primary cause and what or who is responsible. The manufacturer has been contacted and the dealer is saying that he thinks they may have done something that could cause the problem.

Yellowing of polypropylene berber carpet over rebond pad is nothing new and it has been very common. There are primary and contributing causes but the solution is often the same, that is to treat the carpet with a 10% solution of citric acid. However, if this doesn’t work, and sometimes it doesn’t, you may have to look further for compensation from the mill or the pad manufacturer.

On another issue, that I just got finished talking to a dealer about, he has a customer with a 9 year old white wool carpet. The carpet was just cleaned by a professional carpet cleaner and it turned blotchy brown. The cleaner has been back three times to re-clean the carpet. Each time the discoloration goes away and then comes back. The cleaner has now said that the carpet is defective and it’s nothing they’ve done. The carpet is not defective, something that’s being done to change the chemistry in the carpet is causing the problem. If the discoloration comes out when the carpet is cleaned and comes back when the carpet dries, capillary action is bringing a discolorant to the surface. The discoloration is most likely due to a disturbance in the chemical balance of the carpet. Wool is naturally acidic, if the cleaning agent is an alkaline then there can be a reaction that will cause discoloration. When jute was used in woven carpets water based alkaline cleaning agents used to cause a condition known as cellulosic browning. This was caused by a weakening of the jute which caused the lignin in the jute to migrate up the shaft of the fiber. Carried by water up the fiber, which is capillary action, when the carpet dried the lignin left a brown residue on the tips of the carpet. This was referred to as cellulosic browning because jute is a cellulosic material. If the carpet was treated with acetic acid after cleaning the browning was not likely to occur. If browning showed up later a no brown agent could be sprayed on to neutralize the discoloration. This is the same type of condition which exists in this dealers situation. Apparently the cleaner has created a chemical imbalance in the carpet and doesn’t know how to resolve the matter. If the cleaner calls IICRC they will help him resolve this issue by giving him the information and technique he needs.

These problems are not the dealers fault. The second one is not the manufacturers fault and after 9 years they wouldn’t even listen to a complaint. The dealer though is going to be the one the consumer calls with a problem. You have to know what to do and how to get them an answer. If you don’t know you can call here, just like these two dealers did, and I’ll help you too. It costs nothing to ask a question. If we get into more work there is a fee. Don’t scratch your head, guess or procrastinate with your customers concerns. Get help and be a hero to your customers.