Curd soap
Curd soaps , even outdated sodium soap , among the soaps and are generally sodium salts of fatty acids . They are white to brown in color and have a fatty acid content of 72 to 75%. They are mostly obtained from lower quality fats . Curd soaps form the basis for preparations , which are often called fine soaps and are mixed with nourishing additives, perfumes and dyes.
Naming
The name curd soap is based on the production process of soaps, in which the soap core is separated from a soap mass that is boiled in a lot of water by adding table salt ( sodium chloride ), which becomes firmer, so "pithy" as floating mass on top.
Manufacturing
By saponification of fats (are tallow , pork fats and bone) or vegetable oils with sodium hydroxide solution to the sodium salts of the fatty acids and glycerol disassembled. The resulting soap mass is Leimseife called and is the precursor for the production of curd soap. After adding sodium chloride ( salting out ), the soap core floats and is separated off. The water-soluble glycerine and undesirable accompanying substances from the fats remain in the solution (see also soap ).
Properties and use
The fatty acid salts that are produced during manufacture are the actual soap and have a cleaning effect because they have the properties of a surfactant . With the help of the soap, many substances that are not soluble in water - e.g. B. Fats and oils of fossil origin ( mineral oils ) - can be rinsed off with water. In practice curd soaps or preparations based on curd soaps are only used to clean the hands, as they have an alkaline reaction ( pH value above 7) and skin irritation occurs when they come into contact with mucous membranes. In detergents , soaps only play a subordinate role as defoamers because of the formation of lime soaps . Aqueous soap solutions are sometimes used for pest control in crops , e.g. B. against thrips and aphids . Curd soap is also used to shape and create dreadlocks . When cleaning brushes (especially in oil painting), the curd soap ensures that the bristles and hairs last significantly longer. Curd soap has an antiseptic effect and is used with warm water as a home remedy for nail bed inflammation .
See also
Web links
Individual evidence
- ^ Brockhaus ABC Chemie , VEB FA Brockhaus Verlag Leipzig 1965, p. 2092.