In recent years, people have shown greater concern for body odors. Breath, axillary, foot and hair odor are examples of displeasing odors for humans. There are methods of controlling bad smells including hiding them by using stronger fragrance materials, and masking them by using materials that give a vague impression of the original smell in harmony with the actual smell. Although there are various reports on bad breath, axillary odor and foot odor1,2, research into head odor is sparse. Therefore, we have performed the following studies aiming to develop fragrant hair cosmetics that control head odor by inhibiting the formation of head-odor-causing materials:
• Study of head-odor-causing materials • Study of the process of odor formation • Investigation of fragrance materials that can control odor formation • Confirmation of odor formation control
Kubota et al. reported lower fatty acids and aldehydes3 to be key components of head odors. We first performed a study on the materials which cause head odors, and then performed a study to confirm the process of fatty-acid formation. Materials that are able to control the formation of odor components were then investigated. Fragrance materials are known to have deodorizing and antibacterial effects and include many molecular structures. Therefore, using fatty-acid formation models, we carried out the evaluation of fragrance materials that control fatty-acid formation. The results indicate that there are many fragrance materials which control fatty-acid formation. We prepared a trial perfume for hair cosmetics from these fragrance materials that has a fragrance tone suitable for practical use. In a test of the practical use of perfumed shampoo and rinse, the effect on head-odor control was recognized.