Shaving foam

Shaving cream or shaving foam is a frothy cosmetic cream applied to body hair, usually facial hair, to facilitate shaving. The use of cream achieves three effects: lubricates the cutting process; swells keratin; and desensitizes skin. Shaving creams commonly consist of an emulsion of oils, soaps or surfactants, and water.

A rudimentary form of shaving cream was documented in Sumer around 3000 BC. This substance combined wood alkali and animal fat and was applied to a beard as a shaving preparation.

Until the early 20th century, bars or sticks of hard shaving soap were used. Later, tubes containing compounds of oils and soft soap were sold. Newer creams introduced in the 1940s neither produced lather nor required brushes, often referred to as brushless creams.

Modern commercial creams are often sold in spray cans, but can also be purchased in tubs or tubes. Shaving creams in a can are commonly dispensed as a foam and sometimes as a gel that starts turning into foam as it is rubbed into the skin, also known as post-foaming shaving gel. Creams that are in tubes or tubs are commonly used with a shaving brush to produce a rich lather (most often used in wet shaving).

Post-foaming shaving gels have been found to have benefits over regular pressurized shaving cream in the prevention of pseudofolliculitis barbae. This is due to their better hair softening qualities; post-foaming shaving gels allow more water to enter the hair shaft, which leads to the hair becoming softer and easier to cut.

The first can of pressurized shaving cream was Rise shaving cream, which was introduced by Carter-Wallace in 1949. By the following decade this format attained two-thirds of the American market for shaving preparations. The gas in shaving cream canisters originally contained chlorofluorocarbons (CFCs), but this substance was increasingly believed to be detrimental to the Earth's ozone layer. This led to restrictions or reductions in CFC use, such as the United States Environmental Protection Agency ban in the late 1970s. Gaseous hydrocarbon propellants such as mixtures of pentane, propane, butane and isobutane could be used instead of the CFCs. Because of the large proportion of water in pressurized shaving cream, the risk from the normally flammable hydrocarbons was reduced.

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