Sd. Escher et E. Oliveros, A QUANTITATIVE STUDY OF FACTORS THAT INFLUENCE THE SUBSTANTIVITY OF FRAGRANCE CHEMICALS ON LAUNDERED AND DRIED FABRICS, Journal of the American Oil Chemists' Society, 71(1), 1994, pp. 31-40
Model investigations of physicochemical aspects of the substantivity o
f fragrance raw materials on laundered fabrics were performed. The ove
rall process was divided into two consecutive steps, laundry and dryou
t, which were characterized by affinity and tenacity, respectively. Th
e affinities of fifteen fragrance raw materials to cotton and polyacry
lonitrile were measured in standard fabric softener and detergent solu
tions. Affinities correlated with the corresponding partition coeffici
ent, P(o/w). To study the impact of parameters independent of the chem
ical structure of the fragrance molecules, 1-[H-3]-3-ethyl-5-phenylpen
tanol (phenylhexanol) was selected, and aqueous solutions of defined a
nionic, nonionic and cationic surfactants were used as model detergent
and fabric softener media. A sequence of experiments, based on the fr
actional factorial design, was planned for quantifying the relative co
ntribution on substantivity of a number of variables: the concentratio
n of the fragrance chemical, the type and concentration of the surfact
ants, the type and weight of the fabrics (cotton or polyacrylonitrile)
and the washing temperature in the case of cotton. The affinity that
characterizes the washing process depends mainly on the type of fabric
and the type of surfactant and, to a lesser extent, on the surfactant
concentration and the temperature. Anionic and nonionic surfactants,
the main components of detergent powders, behave similarly, whereas th
e combination of cationic surfactant with cotton markedly enhances the
affinity. For phenylhexanol, the tenacity after dryout is largely con
trolled by the type of fabric. The role of fiber swelling is discussed
. The substantivity, which represents the global effect of laundering
and dryout, shows the same trend as the affinity. The complexity of th
e physicochemical phenomena involved is highlighted by the importance
of the interactions between the main contributing factors.