j. Cosmet. sci., 51,263-265 (July/August 2000) Abstracts Journal of the Society of Cosmetic Chemists Japan (as published in Vol. 33, No. 2, 1999)* Development of a New Cationic Polymer for Hair Styling Products and Its Application • Tomoyuki Kawasoe*, Tomoko Watanabe*, Tetsuya Kanbe '3, Tomiyuki Namba '4, Masaaki Uemura '3, Uhei Tamura '3, Kenji Torii '5, Yoshihiro Okuda '6, Junichi Matsumoto '6, Yujiro Uchiyama '6, Depart- ment of Customer Satisfaction Research '2, Product Development Center '3, Basic Research Center '4, Kuki Factory '5, Shiseido Co., Ltd., Osaka Organic Chemical Ind., Ltd. '6 A typical synthetic resin thickener is comprised of a crosslinked polyacrylic acid. It is generally prepared by crosslinking polyacrylic acid with allyl saccha- rose. This carboxyvinyl polymer is one of the most popular thickeners for cosmetics. It shows high abil- ity of gelation, good transparency and pleasant odor. Since this carboxyvinylpolymer structure is anionic, it can be blended with nonionic and anionic poly- mers. However it is incompatible with cationic and amphoteric polymers. This is a disadvantage since cationic and amphoteric polymers yield good textile setting and water repulsion properties of hair respec- tively. Therefore, we carried research towards devel- opment of a new thickener compatible with both cationic and amphoteric polymers. As a result, we developed a new cationic polymer which is compat- ible with cationic and amphoteric polymers. Fur- thermore, it exhibits good thickening properties and high salt tolerance. This new cationic polymer is not only a good thickener but also yields excellent adhesive and setting properties of hair. Styling gel formulation with this new cationic polymer yielded a stable product without stickiness, flaking and with excellent transparancy on hair. Key words: new cationic polymer, non flaking, new- type hair styling gel, non stickiness, gel agent, high These abstracts have been edited only minimally by the Journal of Cosmetic Science. They appear here ba- sically as they appeared in the Journal of the Sodety of Cosmetic Chemists Japan. viscosity, salt tolerance, moisture resistance, cosmet- ics, transparancy. Spectral Assessment of Colored Hair by Means of Photoacoustic Spectroscopy Akiko Ogata**, Natsumi Komure**, Yoshio Tsu- jino**, Teruo Hinoue*** Research & Laboratories, Yamahatsu Sangyo Kaisha, Ltd. ** Department of Chemistry, Graduate School of Science, Osaka Uni- versity*** Reproducible measurements have been desired in the spectral assessment of colored hair, because a rough surface and a heterogeneous internal structure of the colored hair causes the light scattering, which leads to deterioration of reflectance spectra of the colored hair. Since the photoacoustic effect indi- rectly detects optical absorption with an acoustic instrument such as a microphone, it is expected that photoacoustic spectroscopy (PAS) is little affected by the light scattering and thus provides the repro- ducible absorption spectra even for the colored hair. In this work, we measured PA spectra of the colored hair and compared them with the corresponding reflectance spectra. As a result, it was shown, as expected, that the PA spectra were obtained with good reproducibility and were little affected by the light scattering in comparison with the reflectance spectra. PAS is therefore applicable to the spectral assessment of the colored hair. On the other hand, the depth-profiling was attempted on cellophane samples with a laminar structure, and the colored hair by measuring the PA signal intensity at a con- stant wavelength as a function of the chopping fre- quency. The depth-profiling was successfully per- formed for the cellophane sample but not for the colored hair because of its circular cross sectional shape. Further improvement is necessary for the depth-profiling of the colored hair. Key words: spectral assessment, colored hair, pho- toacoustic spectroscopy (PAS), microphone, chop- ping frequency, light scattering, PA spectra, reflec- 263

264 JOURNAL OF COSMETIC SCIENCE tance spectra, optical absorption, reproducibility, depth-profiling, cellophane Properties of the Partially Hydrophilic Silicone Gelling Agent Toshio Nomura**, Kiyomi Yokoohji**, Koji Sakuta*** Fundamental Research Laboratory, KOSE Corporation **, Shin-Etsu Chemical Co., Ltd. *** A partially hydrophilic crosslinked silicone was syn- thesized by the addition polymerization of a meth- ylhydrogenpolysiloxane and a polyoxyethylene dial- lylether. The crosslinked silicone obtained can swell in dimethylpolysiloxane (silicone oil) forming a gel, and a large amount of water can also be successfully taken into the gel to form a stable W/O type emul- sion. The W/O emulsion prepared using the syn- thesized crosslinked silicone was confirmed to have larger water droplets, and to contain a larger amount of water when compared with the emulsion prepared by the conventional silicone type W/O emulsifier (polyoxyethylene methylpolysiloxane copolymer). The larger water droplets of the emulsion is well understood by the fact that the synthesized crosslinked silicone consists of dispersed particles with practically no soluble components, and there- fore has a lower ability of decreasing the interfacial tension between water and dimethylpolysiloxane (silicone oil). The stability of the emulsion in spite of its large water droplets is supposed by the fol- lowing facts: 1) The interfacial film can be effec- tively formed by the dispersed crosslinking silicone which orientares between water and dimethylpoly- siloxane (silicone oil), because of its hydrophilic and hydrophobic moiety. 2) The crosslinked silicone en- tangles its polysiloxane chains in dimethylpolysilox- ane-the outer phase of the emulsion, forming the network. Therefore the dimethylpolysiloxane (sili- cone oil) existing around the water loses its fluidity and stays in a gelling state. And the viscosity of the gel shows little temperature-dependence because of its polysiloxane chain structure. Hence, the water, the inner phase of the emulsion, will not coagulate and the emulsion is stable in a wide temperature range. Key words: gelling agent, crosslinks, silicone oils, gels, water in oil, emulsion, dispersed particles, in- terfacial tension, network, temperature-dependence, theology, particle size, phase diagram Development of a Device to Measure Human Hair Luster Yutaka Tango, Koichi Shimmoro Fundamental Research Laboratory, KOSE Corpora- tion Evaluating human hair luster is important to de- velop hair-care products. Many methods to measure human hair luster have been proposed so far. How- ever, they have some disadvantages: some methods need to cut subject' s hair and some need a long time period. To solve these problems, a new device to measure human hair luster is developed. This new device has some excellent features: It can measure human hair luster accurately without cutting hair. The measurement is not affected by subject's hair- style and/or color. The device needs extremely short time period. The relationship between sensory data of human hair luster and the measurement has a highly correlative coefficient, so the measurement by this new device is effective for evaluating human hair luster. Key words: hair, luster, color, hairstyle, dichromatic reflection model, specular reflection, diffuse reflec- tion,gonio photometric method, direct measure- ment, small device, light emitting diode, photodi- ode Barrier Properties of a Phospholipid Polymer Hydrogel Membrane and Its Enhancement of Stratum Corneum Function Kazuko Jimbo**, Nobuhiro Ando**, Kazuhiko Jshihara*** POLA R&D Laboratories, POLA Corporation** Department of Materials Science, Graduate School of Engineering, The University of Tokyo*** The stratum corneum functions not only by holding water but also by maintaining barrier properties that control transepidermal water loss (TEWL) and prevents permeation of foreign substances. Shaku et al. reported on the double functions of poly [2-methacryloyloxyethyl phosphorylcholine(MPC)]. Our investigation led to discovery of an additional beneficial property of poly (MPC) that acts as a bar- rier and prevents excessive transepidermal water loss of the skin and permeation of foreign substances into the skin. We carried out experiments to deter- mine if poly (MPC) hydrogel membrane with these barrier functions would be beneficial for troubled skin with weakened baffler function. We found that the skin condition of the subjects who had skin troubles before treatment experienced significant improvement after using the experimental sample containing poly(MPC), and that the average surface area of corneocyte used to test barrier function was significantly increased. It appears that the weakened corneal baffler function was repaired by the forma- tion of a hydrogel membrane on the skin, and the stratum comeurn was restored to its healthy normal state. It is suggested that the hydrogel membrane formed by poly (MPC) functions like the corneum and acts as an effective barrier to prevent absorption of foreign substances and to regulate the transepi- dermal water loss.