Having mastered the various stages of stain classification, the spotter must then learn the methods employed in stain removal, which are four in number. Each method has its own particular advantages, employing various pieces of equipment, solvents and chemicals.
The methods of stain removal are designated in the following manner :-
- Mechanical action.
- Solvent action.
- Chemical action.
- Lubrication
Mechanical action
Mechanical action is carried out with the aid of such tools as brush, steam gun, spatula and water gun, these being used to break up and remove the raised or built-up portions of stains, and in some instances helping to release absorbed stains.
Many stains such as mud, water and litharge are practically removed by brushing and manipulation with the spatula, while the steam gun will soften and often remove stains merely by the heat and force of the steam .
Solvent action
This methods may be termed the spotter's main line of attack, as by the use of dry and wet solvents it is possible to eradicate the greater part of the stains encountered after dry-cleaning. Most of the oxidized oil stains, paint and lacquers are removed by the use of dry solvents which dissolve the hardened portions of the stains, so allowing complete removal to be effected by flushing with white spirit of chlorinated hydrocarbon.
Stains which have carbohydrates in their make-up, such as sugars and starches, are removed by wet solvents, the principal of which is water, as it dissolves the majority of food stains.
Chemical action
This term is used to denote the reaction which takes place when a chemical is applied to a stain. Such action is clearly observed when dilute silkorustout or commercial rust remover is applied a rust stain ; in this case the mark is decolourized by the production of a new compound which is more readily removed from the fabric before chemical action is applied to any stain, the affected area should be wetted out with water, as this will allow the chemical action to be more easily controlled, so preventing lose of colour or injury to the fabric.
the same process of flushing should be used when applying sikoinkout, as by saturating the affected area with white spirit, prior to using the more volatile liquids, the evaporation rate of these agents is slowed down, giving a longer period of solvent action without fear of affecting the dyestuff of fibers.
Lubrication
In the removal of insoluble substances such as graphite and pigments the lubrication method of great important. By the application of such lubricants as glycerin, "Vaseline". benzene soap and sulphated fatty alcohol to various spots and stains, insoluble particles are held in suspension, so preventing redeposition in the fabric.
In addition to acting as a carrier the lubricant prevents wear and chafing of the fabric, due to the use of the spatula or brush when breaking up the stain.