When there is a need to remove a stain, a clever idea is to determine its origin first of all. Stain removers can remove the stain altogether or only mask it, but most of them depend on a couple of chemical strategies. It would be beneficial if there was one method to remove all the nasty stains, but specific type of cloth or color may require a certain remover.
Stain removers are mostly surfactants, enzymes and solvents. They usually apply a certain technique to remove the stain, and there are 4 main ones. The first one is dissolving the stain. Solvents, which are a part of any stain remover, remove other chemicals. Therefore, if the stain is oil-based, water-based dissolvent will not help. Alcohol or gasoline will be handier in this situation. A solvent, which chemically resembles the stain, should be used.
The second technique is to emulsify the stain. This technique is based on the surfactants, which cover the stain and lift it from the surface. Soap is a most common surfactant, which removes both water-based and oil-based stains. Absorbing the stain is another possible approach. Enzymes, which break the molecules of the stains, are responsible for that. This method will help to get rid of such nasty stains as chocolate or blood.
As it was mentioned before, there are those stain removers that can only hide the stain, as many of them include whiteners, which make the stain lighter and not so noticeable. If there is a possibility, this technique should be tested on a piece of cloth or on the spot that is not visible before it is applied it directly to the stain, as it is extremely easy to ruin the garment with a bleacher; other chemicals may also have undesirable results. Most of the products, available on the market, use a couple of methods, mentioned above. If the origin of the stain is unknown, one should start with the easiest non-harmful remover (soap or water) and work the way up to more substantial chemicals if the stain does not disappear.