Encapsulation

All carpet cleaning chemicals incorporate detergents to remove soils. Detergents are, by design, sticky so they can attract dirt. They have an affinity for greasy soil, surrounding it to separate it from the carpet fiber. This chemical action is aided by heat, agitation and dwell time.

Even when using a fiber rinse as part of extraction cleaning, some detergent residue will be left on the carpet. And many fiber rinses themselves are sticky! One major carpet mill estimates that up to 4% of detergent used is left in the carpet following hot water extraction, and this residue is additive over repeated cleanings. Any new soil coming into contact with the carpet, such as dirt from shoes in normal foot traffic, will be attracted to the sticky detergent residue left on the carpet. This is referred to as "rapid resoiling", the result of cleaned carpet getting dirty faster than carpet with no residue. Vacuuming removes loose soil, but will not remove dirt attached to sticky residue.
On carpet cleaned with typical cleaning chemicals, dirt attaches to sticky residue and is not removed when vacuumed. Encapsulating cleaning chemicals have crystalline polymers in addition to detergents. After the detergents have attracted and surrounded the greasy soil, the polymers "encapsulate" both the detergent and soil. As this encapsulated soil dries, it crystallizes into a dry (not sticky) residue. For years, this technology has been used in low moisture cleaning methods where the residue is purposely left in the carpet and is vacuumed away. Many carpet cleaners consider the term "encapsulation" to be synonymous with the low moisture cleaning method. But encapsulation is actually a chemical process triggered by the proper formulation of polymers, having application in any type of carpet cleaning detergent. Encapsulation has another significant advantage in all cleaning methods. Leaving crystallizing polymer residue in the carpet prevents spots from wicking back. The polymer encapsulates the wicking spot, creating a crystalline residue as it dries. This is just as effective in hot water extraction cleaning as it is with brush and bonnet.
Dirt does not stick to crystalline residue left behind on carpet cleaned with encapsulating cleaning chemicals.