Hair strengthening and anti-breakage claims currently represent key trends within hair care, with many leading brands such as Pantene, Dove, Elvive and Garnier Fructis including anti-breakage or strengthening variants in their ranges. This has come about because consumers now realise that prevention rather than treatment of damaged hair is preferable in the longer-term.
The flexabrasion study, published in Cosmetic & Toiletries Manufacture Worldwide, May 2005, compared the performance of Croda's hair strengthening agent with D-Panthenol, one of the most popular ingredients used to support hair strengthening claims. The company says the results showed that Keravis, a protein-silicone copolymer, significantly increased the strength of hair fibres from both conditioner and shampoo formulations.
The Croda product provided strength improvements at all test concentrations and relative humidities. Surprisingly D-Panthenol, more commonly known as Pro Vitamin B5, offered no strength benefits at any test concentrations when delivered from a conditioner or a shampoo.
Commenting on the results, a Croda spokesperson said: "Many consumer advertising campaigns promoting hair care products are based on improving hair strength and reducing hair breakage. D-Panthenol has been regarded as the industry-standard to provide such claims. Hair care formulators will find these new results interesting as they are scientific proof of the real strength improvements possible with Keravis."
Croda says that the complex is effective for both conditioner and shampoo bases, and that during testing hair strength was increased at all relative humidities, notably also at humidities where hair would normally be weaker.
Keravis has an average molecular weight of 1800 Daltons, low enough for a significant portion to penetrate into the hair cortex. Once there, its hydrophilic nature provides excellent moisture binding capacity. It also has the ability to cross-link on drying to produce a film-forming polymeric structure - a key factor contributing to its hair strengthening functionality, Croda claims.
The study used flexabrasion fatigue lifetime testing, an instrumental technique considered to be a method very relevant to the impact of normal grooming influences on hair strength. Testing was carried out on bleached European hair from a conditioner (1:5 water dilution) or shampoo (1:10 dilution).