Regardless of which cleaning method you use, there will always be some residues remaining in the carpet after cleaning.
One can use any type of pre-spray on the market, use an alkaline, neutral, or acidic rinse, there will always be some residue left behind.
This may sound terrible, but it does not have to be.
20 years ago it was the alkaline pre-sprays or pre-conditioners which were enjoying preeminent popularity. If these were not formulated correctly, yellowing could occur on some lightly coloured carpeting which was removeable using an acid rinse as a post treatment. These kind of complaints were neither profitable nor popular due to the time removal of them meant. Another disadvantage was that the residues often lead to rapid resoiling, meaning that another complaint after a relatively short time was pre-programmed.
These type of incidents are long a part of history. Of course there are still alkaline pre-sprays and pre-conditioners, but meanwhile they have been formulated smartly. CEBE has had an alkaline pre-spray, Traffic Lane Cleaner, on the market for more than 30 years. In addition it was joined by Top Action, a product of the newer, more modern generation.
Alternatively one may also work with an acidic extraction cleaner as a rinse in order to increase success. Our Tapi Soft is an example for this type of product. Pre-spraying with Top Action followed by extraction with Tapi Soft removes more residues not only of loosened dirt but also of the pre-spray used, thereby leaving the carpet cleaner. In addition it leaves the fibres soft (for velours) and best of all this clean will slow down resoiling even beyond the high standard that Top Action was developed on. This philosophy may be transferred to upholstery cleaning by the way.
Back to the residues. Generally speaking there are the following types:
- soap/surfactant residues
- alkaline residues - acidic residues - neutral residues - residues caused by water - powder rersidues
A big problem, with which every cleaner has been confronted in his/her career is the soapy residue in the carpet. As one begins cleaning, one notices that one can't put enough Defoamer into the waste water tank.
This problem is easily recognizable before you begin cleaning: simply fill a spray bottle with water and spray onto a small area in the middle of the area to be cleaned. Then use a spotting brush and massage the area gently. If a soap problem exists then it will become visible almost immediately. With a pH-paper strip you can also determine the pH of the residue easily. Usually it will be neutral to strongly alkaline.
At this point it is advisable to use an acidic extraction cleaner like our Tapi Soft and extract the area. If you have the possibility of using warm/hot water: DON'T- as higher temperatures cause even more foam to build up. In addition you may want to add a defoamer like our Defoamer in order to minimize the foam in the waste water tank. If the result is not satisfactory, you can now proceed with your originally planned cleaning procedure.
This whole process may sound time consuming but this way you will achieve the best possible results with your cleaning products and procedure. If you do not first remove the residues you will most likely prevent your chemicals from doing the work they were formulated to do.
Alkaline residues are excellent shoe cleaners, for example. Why? Alkalinity is the ideal dirt loosener. However, if the alkalinity is high, then the carpet may have a crusty grip and resoil rather quickly. Of course, as mentioned earlier there are a number of highly effective alkaline pre-sprays and cleaners on the market, like our products Traffic Lane Cleaner, Top Action, or Liqua Steam, which through perfectly adjusted alkalinity will not cause this type of problem.
Acidic residues are formed when one neutralizes an alkaline pre-spray with an acidic product and uses too much or rinses too much.These type of residue are generally speaking not a problem. The acidic rinse, like our Tapi Soft, for example, contains an acid that is not a problem for the carpet. This should not be confused with acidic sanitary cleaners that can easily cause discoloration/bleaching on polyamid carpeting, for example. In addition Tapi Soft gives the carpet a soft grip (fabric softening effect) and may even slightly improve the resoiling behaviour due to the extreme rinsing of not only residual cleaning product but also loosened residual soil/dirt.
Neutral residues are becoming more and more popular - the products have a very good detergency and are also pH-neutral. Examples of products from our selection would be BioGreen, BioGreen-liquid, or BioMatrix®.
Water is also a very popular rinse. One can only mention that, when using an alkaline pre-spray a neutralization of same will only proceed very slowly (one would need a large quantity of water). In addition the cleaning process is only continued in a limited manner. Conclusively one can confidently say that it is always better and more effective to use a suitable extraction cleaner or rinse when removing residues instead of only water. Our products Liqua Steam and Tapi Soft are two excellent examples of these types of products.
Powder residues remain behind when using the dry powder extraction method. These residues are left to dry in order to be removed by thorough vacuuming. The better the vacuum cleaner used, the less residues will remain behind. In addition the amount of residue is dependent on the structure of the carpet. Every additional pass with the vacuum cleaner will remove more residue.
In conclusion one can say that when having carried out a proper cleaning with the correct products and proper machinery and accessories, no harmful residues will remain behind. As long as the products used are suited for the situation the result will be accordingly good and the resoiling behaviour too. Just like the choice of method of carpet cleaning, so too the choice of the right product will depend on the individual situation as well as the experience of you as the user.