New Mexico Cosmetology Practice Exam

Formaldehyde is commonly found in hair straightening treatments and is included for its ability to create a smooth and straight appearance in the hair. This chemical works by forming a bond between keratin proteins in the hair, which modifies the texture and can make it straighter and less frizzy. Its effectiveness is linked to its ability to penetrate the hair shaft and interact with the disulfide bonds that typically contribute to natural curl and wave patterns. Treatments that use formaldehyde or formaldehyde-releasing ingredients are popular in salons seeking to provide long-lasting straightening effects. In contrast, sodium chloride, found in some hair care products, primarily serves as a thickening agent and does not have the same purpose or effect as formaldehyde in hair straightening. Gelatin is a protein derived from animal collagen and is often used in conditioning treatments, not straightening. Carbomer is a thickening agent used in various formulations for stabilization, but it does not contribute to hair straightening. Understanding these differences helps clarify why formaldehyde stands out as the primary chemical in this context.