Bar Soaps Lec 5

Question 1

Types of bars

Answer 1

Soap bars, combars, syndets

Question 2

Composition of soap bars

Answer 2

90% Sodium or potassium soap, pH 9-10. ex) ivory soap

Question 3

Composition of combars

Answer 3

75% sodium or potassium soap, plus 25% synthetic detergent, pH 8-9. ex) Lever 2000

Question 4

Composition of syndets

Answer 4

Less than 10% soap, plus 75% synthetic detergent and fillers, pH neutral.

Question 5

What is tallow soap?

Answer 5

From beef fat. Consists of higher chain salts of fatty acids (C 18), used for harder bars and mildness. Doesn’t lather well and is drying.

Question 6

What is coconut soap?

Answer 6

From coconut oil. Consists of medium chain fatty acids (C 12), used for richness of lather but is drying to skin.

Question 7

What is the role of stearic acid in soap?

Answer 7

Provides skin conditioning but can enhance bar melting; often positioned to the consumer as the moisturizing cream.

Question 8

Kligman soap chamber test

Answer 8

good method to separate soaps, combars, and syndets. Selects for dryness and flaking. Doesn’t predict irritancy of rinsible soaps like TEA soaps. Doesn’t mirror actual use.

Question 9

Rhein modified soap chamber test

Answer 9

Good for soap bars and combars, good for supermild liquid cleansers, doesn’t pick up dryness, and not consumer use relevant. Scores erythema, TEWL, and chromameter.