Society of Cosmetic Chemists

A new test developed to characterize the bending properties of treated or virgin hair fibers is described. The device consists of a pendulum that bends a sample made up of 39 parallel hair fibers at each swinging stroke. Hair bending stiffness can be assessed by the number of strokes observed until the pendulum stops. The mechanical behavior of natural hair fibers is related to their geometric characteristics. The effects of various hair treatments can be assessed by this method.

J. Cosmet. Sci., 52, 369–375 (November/December 2001)

A modified cup scrub method for assessing the

antibacterial substantivity of personal cleansing products

WARD L. BILLHIMER, CINDY A. BERGE,

JAN S. ENGLEHART, GAYLE Y. RAINS, and

BRUCE H. KESWICK, The Procter & Gamble Company,

Cincinnati , OH 45241 .

Accepted for publication August 15, 2001 .

Synopsis

An improved in vivo method for evaluating the antibacterial substantivity or residual effectiveness of bar soaps and other personal cleansing products is presented. The effectiveness of an antibacterial bar soap containing 1.5% 3, 4, 48-trichlorocarbanilide (TCC) versus its soap vehicle was evaluated under simulated conditions considered optimal for bacterial growth, proliferation, and possible infection. A washout period to clear the skin of any antimicrobial agents previously used was followed by a treatment period in which the subjects washed one of their forearms with the antibacterial soap and the other forearm with the soap vehicle. Either immediately or 24 hours following the final wash, three test sites on both forearms were inoculated with S. aureus and occluded with Hill Top Chambert patches. At intervals of 30 minutes, two hours and five hours, the patches were removed. The bacteria on the skin were harvested using the Williamson-Kligman scrub technique (1,2) to determine the number of surviving CFUs at each time period. The method successfully demonstrated that sufficient TCC had remained on the skin for 24 hours after the final wash to effectively inhibit the growth of S. aureus on the skin for as long as five hours after inoculation.

J. Cosmet. Sci., 52, 377–389 (November/December 2001)

Hair photoprotection by dyes

CHANDRA M. PANDE, LINDA ALBRECHT, and

BRIAN YANG, Clairol Inc., 2 Blachley Road , Stamford , CT 06922 .

Accepted for publication August 15, 2001 .

Synopsis

We have found that hair dyes protect hair against photodamage. The efficacy of photoprotection of dye products has been measured by monitoring the tensile strength of hair fibers and the integrity of the disulfide bonds in the fibers. Although the hair dyed with permanent dye products are initially weakened due to oxidative chemical damage, they also show a slower rate of degradation upon photoirradiation, compared to the undyed hair. Thus, a less appreciated benefit of using hair colors is their ability to provide protection against sun damage.

J. Cosmet. Sci., 52, 391–397 (November/December 2001)

Diurnal variation affects age-related profile in

skin thickness

KAZUE TSUKAHARA, YOSHINORI TAKEMA,

SHIGERU MORIWAKI, TSUTOMU FUJIMURA, and

GENJI IMOKAWA, Biological Science Laboratories, Kao Corporation,

2606 Akabane, Ichikai, Haga, Tochigi 321-3497, Japan .

Accepted for publication August 15, 2001 .

Synopsis

We have previously demonstrated that over the course of each day there are changes in skin thickness that can be measured by B-mode ultrasonography. This suggests that there is a shift in dermal fluid from the face toward the legs by gravity, resulting in a diurnal variation in skin thickness. Therefore, age-dependent profiles in skin thickness were evaluated by B-mode ultrasonography in the morning or in the afternoon for 130 normal Japanese females aged 18–83 years. Three areas of the face (the forehead, the corners of the eye, and the cheeks) were measured as distinctively sun-exposed areas while the flexion side of the forearm was measured as a weakly sun-exposed area. A weak correlation between skin thickness and age was found in all areas measured (positive for the forehead, the corners of the eye, and the cheeks; negative for forearms) in the morning but not in the afternoon, when only a weak positive correlation was observed in the cheek. These results indicate that when measuring skin thickness, an appropriate time for taking measurements should be selected with consideration of the movements of dermal fluid over the course of each day.

J. Cosmet. Sci., 52, 399–405 (November/December 2001)

Simultaneous quantitative determination of fluorine and

sodium monofluorophosphate in oral hygiene products

LAI-HAO WANG, Department of Applied Chemistry, Chia Nan

University of Pharmacy and Science, Tainan , Taiwan 71710, R.O.C.

Accepted for publication August 15, 2001 .

Synopsis

An ion chromatographic method for simultaneous quantitative determination of fluorine and sodium monofluorophosphate in oral hygiene products is described. The liquid chromatographic system consisted of an IC A1 polymethacrylate-based anion exchanger and carbonate buffer (pH 9.85) as the mobile phase with a conductive detector. Various excipient ions were investigated with respect to their interference with the determination of fluoride. Comparison with results obtained from a fluoride-ion electrode technique show good agreement.

J. Cosmet. Sci., 52, 407–426 (November/December 2001)

Papers presented at the Annual Scientific Seminar of

the Society of Cosmetic Chemists

(Friday’s Program)

May 10–11, 2001

Sheraton New Orleans

New Orleans, Louisiana

J. Cosmet. Sci., 52, 427–431 (November/December 2001)

AUTHOR INDEX TO VOLUME 52

J. Cosmet. Sci., 52, 433–436 (November/December 2001)

SUBJECT INDEX TO VOLUME 52