Particulate matter is finely divided contaminants present on the surface of the substrate to be cleaned, including smut, pigments, drawing materials and shop dirt. However, for discussion purposes, simple waxes, vegetable oils and animal fats, which may have been applied to facilitate processing operations or rust prevention, may be included. Oil, by definition, is a petroleum-based product. Materials to be removed are classified into two general categories: oil and particulate matter.
deflocculation - disperses contaminants into very fine particles that are suspended in the cleaning solution. emulsification - surfactants in the cleaning solution suspend contaminants in the aqueous phase for easy rinsing and. detergency - surface active agents, or surfactants, reduce the interfacial tension between solution and contaminant, enabling cleaning solutions to better penetrate and displace contaminants from the metal surface The most widely used industrial solvents are cements (trichloroethylene, tetrachloroethylene), adhesives (toluene, ethyl acetate and various ketones), thinner (mineral spirits, benzene, acetone trichloroethylene, tetrachloroethylene) and paint or varnish remover (acetone, toluene, benzene, dichloromethane). saponification - chemically converts drawing compounds (organic oils and fatty acids) into water-soluble soaps that can add to cleaning efficiency. solvent action - enables the cleaner to dissolve oils present on the metal surface. Regardless of the type or category, all cleaners remove contaminants from a substrate by one or more of the following principles: This allows the surfactant molecule to create an oil-water emulsion that is easily rinsed away. 
Surfactants have one end that is soluble in water (hydrophilic) and one end that is soluble in oil (hydrophobic).
Once the contaminant is in solution, the wetting agent creates an emulsion, preventing redeposition onto the part being cleaned. Wetting agents (surfactants and synthetic detergents) aid in removing contaminants by lowering the surface tension of the solution, allowing the cleaner to get under the contaminant and displace it from the metal surface.
0 kommentar(er)
