Shaving soap

Shaving soap typically refers to a hard soap that is whipped into a lather using a shaving brush. The lather it produces is used to coat the face during shaving, providing protection and lubrication for the razor. Among most wet shavers, shaving soap has largely been displaced by canned shaving foam or gel, but hard shaving soaps have a following among shaving traditionalists especially among straight razor users.

Hard shaving soaps in their modern form have existed since at least the early 19th century. Williams (a common American shaving soap intended for use in a mug rather than a scuttle) has been produced since 1840, and a US patent for a shaving scuttle for use with a hard soap was granted in 1867.

Shaving sticks (shaving soap formed into a cylinder) have existed at least since the mid-19th century.

Traditional shaving soap is often sold as a round puck, either with a rounded bottom intended for use with a shaving scuttle or a flat bottom for use in a mug. High-end soaps may be sold with their own dishes, typically made of either wood or ceramic, and be formed to fit the dish the puck is sold with. Shaving soap may also be formed in a stick, sold either in a plastic tube or wrapped in foil or paper. Shaving soap is more rarely sold as rectangular bars (as is common with body soap).

A hard shaving soap is used with a shaving brush to create lather for shaving. For soap in the form of a puck or bar, the brush is first soaked in water and then swirled vigorously over the surface of the soap, causing moist soap to coat the brush's bristles. The brush is then transferred either to a separate bowl or to the shaver's face to be lathered.

Shaving sticks are typically used by rubbing the exposed end of the stick across the shaver's face, coating the face with soap. The soap is then lathered with a moistened brush. Owing to their compact form and ease of use, shaving sticks are popular for use while traveling.

Shaving soap is produced like a traditional soap with an ingredient selection oriented to producing a stable, slick lather. Its manufacture often differs slightly from normal bath soap in that both potassium hydroxide and sodium hydroxide may be used as saponification agents. Sodium hydroxide creates a harder soap such as is used in pucks, where potassium hydroxide facilitates creation of a softer soap which loads on the brush more easily. Historically, tallow has been a popular ingredient in shaving soaps and is still in use in some traditional products. Palm oil is frequently used as a substitute for tallow where animal fats are not desired. Other oils such as coconut oil are commonly used. Component fatty acids such as stearic acid are also used in shaving soaps for the properties which they contribute; stearic acid contributes to a more stable dense lather.

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