84 JOURNAL OF COSMETIC SCIENCE
Tt is seen that CS-20 and HCE color bases fonned very clear ML V structure, and the detennined average
particle sizes are: Ceteth-20: J.8µ.m CS-20: 6.0 µm HCE: 12.5 µm. The average particle sizes are in the
following decreasing order: HCE CS-20 Ceteth-20.
2. SAXS Patterns
Figure 2 explains SAXS 2D diffraction patterns of three tested color bases. Different SAXS patterns
were observed on these bases. It was determined that the CS-20 color base exhibited hexagonal crystal
phase with smaller average particle size, narrower size distribution, and larger space constant (d ~124 A).
The HCE dye base formed cubic crystal phase with larger average particle size. broader size distribution,
and smaller space constant (d -95.7 A). It is interesting to note that Cetelh-20 color base formed a clear
lamellar s1ructure with the largest space constant of 146 A.
C�20 v,. ..,.........:.
.
.
:
....
.
.
.............·"·"�J....... ..................· ..........�(l.'L............ .........................•.:A·': ....Figure 2 SAXS spectrum and diffraction patterns
l. DSC Study
DSC phase transition temperature and enthalpy are listed in Table 1.
Color Base Sample Transition Temper-..ature (°C) Transition EnthaJo,· (J/2.)
Ceteth-20 62.2 6.24
CS-20 65.9 10.14
HCE 56.] 7.03
It can be seen that CS-20 dye base demonstrated higher phase transition temperature and larger transition
enthalpy. which were corresponded to its well-organized liquid cry·stal structure, while HCE dye base
showed lower phase transition temperature and smaller transition enthalpy.
References
I. T. Gao, J Tien and Y Choi, Sunscreen formulas with ML V structure, C &T Magazine, I 18 (I 0), 41
-48. 2003
2. T. Gao, PhD, A. Pereira, Y. Choi, J. Tien and R. Lanese. A Novel Phosphate Esler for Hair-
coloring Enhancement, presented at the Annual Scientific Seminar of SCC, June, 2005, Las Vegas
and published on J. Cosmetic. Sci., 56, 374 -75, 2005.
3. T. Gao, PhD, R. Akatsuka, R. Bord, and A. Pereira, Multilayer Lamellar Vesicles in Oxidative
Dye Formulations -Characteriz.ation and Performance", C&T Magazine, 121 (5). 75 -88, 2006.
cknowledgment
Authors thank Dr. Kurt Erlacher of Bruker AXS Inc. for his excellent work on SAXS

2006 ANNUAL SCIENTIFIC MEETING
REDEFINING HAIR BASELINE PARAMETERS IN SOME CLAIMS WORK
K. R. Ramaprasad, Ph.D., Mythili Nori and Yash K. Karnath, Ph.D.
TRI/Princeton, PO Box 625, Princeton, NJ 08542
Introduction
85
l11e quantification of formulation induced beneficial effects on single hair fiber and assembly properties
is central to proper claims substantiation. In U1is context, U1e choice of methods and the specific aspect of
Ute fiber property need critical scrutiny. Standard measurement protocols for any of the numerous hair
attributes do not exist, which makes it difficult to compare perfonnance of diverse products. Reversal of
tensile damage by hair care products is a popular claim. To that end, it is the general practice, in studying
the potential beneficial effects of formulations, to damage the hair to some extent, the nature of which is
determined by the particular hair attribute under study. In examining the effect on hair strength, for
example, the hair tress is bleach damaged. For combing claims, a mild bleach, followed by a mild penn, is
an accepted protocol. Tite goal of this work is to examine the connection, if any, between the damage
history of the hair and the extent of product efficacy, focusing on tensile strength and combability
Ex1erimental
Hair: Medium brown European hair was tl1e primary stock for all the experiments.
Hair damage: For tensile strength measurements, an over-the-counter (OTC) product was used to
bleach the hair to different levels (characterized by a reduction in break stress of 13, 27 and 37%).
Mild bleach-and-1erm damage: For combing work, Ute hair tresses were mildly peroxide bleached,
followed by a mild ammoniwn thioglycolate perm.
Tensile strength: The following solutions (5% w/v) were used for studying changes in tensile
properties: Sodium Lauryl sulfate (SLS)-anionic surfactant Cetyl trimetbyl Ammonium Bromide (CT AB)-
cationic surfactant Cocamidopropyl Betaine (CAPB)-Amphoteric surfactant Triton-X-100-non ionic
surfactant. l11e rationale for their choice is discussed in the results section. The various bleach damaged
hair tresses were treated, respectively, with 5% solution of SLS, CTAB, CAPB and Tritonx-100. After a
contact time of 15 min,, they were rinsed in tap water. Tensile properties of hair fibers were measured
using Dia-Stron ™. l11e undamaged hair was considered as the control.
Combability: An OTC formulation that had been shown to have a good conditioning effect on hair was
used to investigate improvements in combability on hair tresses with different damage levels. Product
application was followed by I min contact time and 1 min rinsing in tap water. TRl's double comb method
was used for measuring Ute combing forces of the iresses. All measurements were carried out only after
conditioning tl1e hair overnight at 65% RH and 21 °C.
Results and Discussion -Tensile Pro1erties
l11e set of neat actives used for this study was selected on the basis Utat one or more of Utem are
common ingredients of most shampoos and conditioners. As such, if tl1ey individually had a beneficial
effect on the tensile strength of hair, tlten it is difficult to ascribe any claims value Wl3.1Dbiguously to a
particular conditioner active that is a co-constituent with any of them. Though all the tensile parameters
were calculated, in the interest of brevity, only the break stress will be presented for discussion. The
progressive bleaching carried out resulted in hair wiU1 reductions in break stress of 13%, 27% and 37%,
respectively, compared to the unbleached control. l11e break stress results obtained using 5% SLS are
shown in Fig. 1.
It is seen tltat SLS has very little effect on U1e tensile strength of wibleached brown hair. However. with
bleach damaged ltair, tbe effect of this common surfactant molecule has a pronounced dependence on the
level of damage. For example (Fig. 1), at a 15% bleach damage, a S %SLS solution has no significant
ff �,t on the tensile strengtJ1 cf hair fibers. As tl1e dm!'.age !eve! increases, th� improvement brought on by
SLS also increases. At 37 %damage, tl1ere is an 11 %improvement in break stress. The dependence of