TAGS: Hair Care
Kao Corporation’s Hair Care Research Laboratory has researched the characteristics of fine particles adhering to hair as a factor for degradation of hair texture the day after washing. Results of the investigations identified factors which effects the adhesion property of dirt particles, such as dust and pollen, to hair.
Furthermore, in consideration of the presence of liquefied oil on hair as a factor that increases particle adhesion, a method for suppression of that by technologies included in shampoo and hair conditioner products was developed.
Study Adhesion of Fine Dirt Particles to Hair
Cedar pollen, used as a representative of fine dirt particles, was examined in the study performed in Tochigi Prefecture. During the period from March to April 2019, a hairpiece, hair bundle, and clothes were placed outside in the air for a few hours each day, then the amount of cedar pollen antigen attached to each sample was quantitatively determined using ELISA.
Hair collected from the bundle was treated with gentian violet staining protein and observed under a light microscope. Spherical particles were stained in blue and adhesion of pollen to individual hairs was confirmed.
A comparison of allergen quantity per unit area revealed that the amount adhered to hair was equal to or greater than that adhered to clothes.
Development of Technology Based on the Findings
Based on the findings obtained in the study, it was speculated that one of the causes for hair contamination with fine particles is the presence of oil. In this study, technologies used for controlling oil on hair were examined for their dirt shielding effects.
Regarding sebum, shampoo that washes the entire hair including the root and conditioner with silicone blended for improved texture of the formula were focused on for development. For reducing liquid-state sebum present on the hair surface, various oil absorbent substances were screened. Cationized hydorxypropylcellulose (C-HPC), developed in the Kao laboratory, was blended into the test shampoo.
At 20 hours after shampooing, elevation of the coefficient of static friction, a parameter for adhesion of fine dirt particles, was significantly suppressed as compared to without the compound. For the test hair conditioner, the results indicated that use of low-viscosity silicone would be effective.
Based on these findings, subjects were instructed to use the test shampoo and hair conditioner in combination for six days on one side of their head. Black hairs were then collected and exposed to white-colored fine particles to evaluate change in color by six research staff members. The results revealed that adhesion of fine dirt particles was significantly inhibited by use of the test products.
The findings obtained in this study will be used for future development of hair care technology and formulation. The results of this study were presented at the Annual Autumn Meeting of the Society of Fiber Science and Technology in 2019.
Source: Kao