J. Cosmet. Sci., 60, 187–197 (March/April 2009) 187 Study of hair shine and hair surface smoothness TIMOTHY GAO, ABEL PEREIRA, and SAM ZHU, Croda Inc., 300-A Columbus Circle, Edison, NJ 08837. Synopsis A new hair visual appearance measurement system called SAMBA from Bossa Nova Technologies (Venice, CA) has been employed to measure effects of cosmetic treatments on hair shine and surface smoothness of different types of hair samples. Experimental procedures for evaluations of shine value and surface cuticle angle of hair samples treated with rinse-off products (shampoo or/and conditioner) have been successfully established and applied. We demonstrated that hair spray and conditioner formulas containing PPG-3 benzyl ether myristate (PBEM) (1) showed great performance on shine enhancement for hairs with light and me- dium colors. Instrumental measurement of shine values was also conducted to compare different commercial shampoo and conditioner products. This study showed reliable utility of SAMBA system and demonstrated the shine enhancement of PBEM in hair care. INTRODUCTION Hair luster (gloss, shine) is an important feature of hair appearance, and this attractive visual effect is a key consumer objective in the hair care market. However, the percep- tion of hair shine is affected by many factors such as lighting environment, hair color, surface smoothness, hair morphology, hair mass density on scalp, and hair fi ber align- ment. These factors make it diffi cult to conduct meaningful shine measurements. SAMBA, a hair luster evaluation apparatus, has been recently applied to study effects of cosmetic treatment on hair shine and surface smoothness (2,3). In a SAMBA mea- surement, a hair tress is illuminated and the different types of light refl ected are col- lected. Using polarized illumination coupled to polarization analysis, SAMBA is able to differentiate the specular and diffusive refl ection. The specular refl ection gives in- formation about hair gloss and roughness, while the diffused light gives information about the hair color. By acquiring two states of polarization at video rate, SAMBA can be used to determine changes in hair shine indexes and surface cuticle angles of hair samples before and after cosmetic treatment. In this study, we established experimen- tal procedures for hair treatment with rinse-off products and demonstrated that PBEM, an emollient ester used in many hair care formulations, improved hair shine. Effects of treatments with commercial shampoo and conditioner products on hair shine were also quantitatively measured by employing SAMBA as the polarimetric imaging system.

JOURNAL OF COSMETIC SCIENCE 188 EXPERIMENTAL MATERIALS O PPG-3 benzyl ether myristate (Trade name: Crodamol STS, Croda Inc., Edison, NJ) O Quaternium-91 conditioners (compositions listed in Table IV), Croda Inc., Edison, NJ O Commercial shine shampoos and conditioners O Blond, medium brown, dark brown, Asian black, and light bleached hair (Interna- tional Hair Importers, Inc, New York) HAIR SAMPLE PREPARATION Hair cleaning. Hair tresses, about eight inches in length, one inch in width and approxi- mately 7.5 grams in weight, were washed and air-dried overnight as follows: O Immerse the hair tress into 200 ml isopropyl alcohol (IPA) for 10 minutes keeping the wax strip out of solvent. O Soak hair tress in 1.6% sodium laureth sulfate (SLES) warm solution (50°C) for 30 minutes keeping wax strip out of soak solution while getting as much hair as possible in solution. O Rinse each tress with tap water to fully remove previously used washing solutions. O Wash hair tress with 1 ml of 16% SLES solution for 1 minute then rinse under running water for 30 seconds. Repeat this step 2 times. O Rinse each hair tress in tap water to remove remaining SLES. O Air-dry at room temperature (25°C) overnight. Hair treatment. Shampoo and/or conditioner treatment procedures were conducted as follows under strictly controlled conditions: O Weigh and record weight of each tested hair tress (including the glue wax). O Calculate the weight of applied product to each single hair tress using the weight ra- tion of 7.5 to 2 (2.0 grams of product applied to 7.5 grams of hair). O Wet the hair tresses and massage the product through the hair tress (both sides) using fi ngers (with a latex glove) and leave the product on the hair surface for 3 minutes. O Prepare 2000 ml of deionized water in a glass beaker dip the treated hair tress into the water for 5 cycles. Squeezing out extra water using fi ngers before dipping in the water for the next cycle (5 cycles of dipping and squeezing). Repeat this step 2 times. O Allow hair tresses to dry overnight at room temperature (25°C). HAIR SHINE MEASUREMENTS Luster values have been characterized by hair care scientists using classical gloss me- ter, shine box, goniophotometers, and other instruments to tentatively quantify human perception of hair shine (4–6). SAMBA software calculated different luster formulas such as Reich-Robbins, TRI, Stamm, Guiolet and Bossa Nova Technologies (BNT) simultaneously. In this paper, we used BNT luster (LBNT) formula for data analysis, which is a Reich-Robbins formula adapted to polarization measurement. LBNT is defi ned as: