I. Principle of action
Water-based detergents work in synergy with chemical (emulsification, saponification, decomposition), physical (penetration, dispersion) and biological (enzyme catalysis) actions to strip dirt from the surface and stabilise it in suspension in the water, with the cleaning effect ultimately achieved by rinsing. Different formulations of detergents adjust the proportion of ingredients according to the type of target stains (e.g. oil, protein) to achieve optimal stain removal.
3, to prevent the emulsified oily dirt and dispersed solid dirt re-deposited on the surface of the substrate.
If a certain mechanical force is applied in the above process, the cleaning effect will be greatly improved.
Second, the choice of surfactant
Due to the different cleaning substrates, select the appropriate cleaning agent, cleaning environment is divided into: neutral, acidic, alkaline, the correct choice of surfactant will play an important role.
1. When pickling
In order to improve the effect of pickling, that is, to accelerate the dissolution of the oxide layer, delay the corrosion of the acid on the substrate, inhibit the diffusion of hydrogen atoms to the substrate, often add a small amount of surfactant in metal pickling. Solution, because the addition of surfactant will form a film on the metal surface, play a certain role in corrosion inhibition.
2. Alkaline washing
The main role of surfactants is to reduce surface tension, emulsification and dispersion of dirt, thereby significantly improving the cleaning efficiency.
Nonionic surfactants (such as alkylphenol polyoxyethylene ether, polyether, etc.) have good wettability and permeability.
1, adding a small amount of surfactant can reduce the surface tension between the substrate and the liquid surface, improve the permeability, so that the lye better contact with the oil, the formation of a saponification reaction, to remove some of the grease.
2, adding surfactant can increase the emulsification and dispersion of oil.
3, in the solvent cleaning process. The main surfactants used are ethylene oxide adducts of esters, ethers and amines or mixtures of them, and mixtures of nonionic and anionic surfactants can also be used.
The choice of surfactant depends on the type of solvent and the type of detergent emulsion to be prepared. In addition, some co-solvents should be added to the solvent-based detergent to improve the solubility of the solvent (e.g., higher alcohols, glycols, glycol derivatives, etc.).
