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Soap glossary – What is the difference?

Curd soap

Sodium soap with a fatty acid content of 72 %
(roughly corresponds to AWS = active washing substances)

Marseille soap

Curd soap with a minimum fatty acid content of 72% in accordance with the purity laws established by Ludwig XIV. These soaps are often produced from olive oil.

Fine soaps or toilet soaps

Low water content (80% fatty acids), high quality soaps, primarily used as body care products.

Glycerin soaps

Molded transparent soaps made with the help of alcohol and glycerin.

Transparent soaps

Normal fine soaps which are rendered transparent by the inhibition of crystallization.

Floating soaps

Are produced by pumping air or a substance having a density less than water into a hollow cavity within the soap, thus enabling it to float (a great many were produced during World War II).

Soft soaps

With the help of potassium hydroxide, these liquid and pasty soaps are primarily used for cleaning.

Liquid soaps

In the majority of cases this is not a soap at all(!), but a synthetic tenside.

Shaving soaps

These high stearin content soaps are produced with potash and caustic soda in order to ensure higher foam strength for wet shaving.

Gall soap

Made from beef gall, this soap is particularly effective in removing fat and proteins.

Anti-bacterial soaps

The addition of bacteriostatic agents makes this kind of soap (e.g., Farnesol) much more effective in fighting germs than normal soaps.

Filled soaps

Chalk or talc filled soaps with added wheat starch for the mass market.

Synthetic soaps

These are not(!) soaps, but rather cleansing bars produced from tensides, mostly with a low pH value ranging from 5,8 - 6,2 for problem skin.


Cleansing bars produced with a combination of soap and tensides in order to neutralize the deficits of both categories.