HAIRCARECUBE^TM (HCC) is a new additive for hair products that allows the active ingredient to penetrate into the hair. During the course of percutaneous absorption studies, we discovered that lyotropic liquid crystal promotes the skin’s absorptiveness to medicines. We conducted a study to determine whether or not lyotropic liquid crystal could be applied as a penetration-enhancing agent in hair, and as a result we have succeeded in developing HCC. In place of hair dye, we used fluorescein-HCC to evaluate hair permeability, and strong fluorescence was observed as deep as the core of the hair. Moreover, the strength of the fluorescence was dependent on HCC concentration. This result did not change under acidic or basic conditions. In addition, the same trends were observed when using an oxidative hair dye. Furthermore, when HCC was used together with hydrolyzed keratin, which repairs hair damage, a stronger restorative effect was observed. These results confirmed that HCC has the effect of promoting the permeation of pigments and other active ingredients into hair. HCC is expected to be very useful as an additive for developing functional cosmetic hair products.