頭髪用エアゾールフォームの官能評価とレオロジー特性

抄録

The texture of Hair Foams is closely related to their rheological properties. In this study, we evaluated the texture of 9 representative Hair Foams using the psychorheological approach.
Flow curves of the foams showed typical thixotropic behavior. We calculated Bingham yield value S_B and apparent viscosity η_a (at a maximum shear rate 280sec^-1) from the ascending portion of the curve. S_B ranged from 200 to 1100dyn/cm² and η_a from 0.5 to 4.0 poise. We applied Maxwell model composed of four elements to represent the kinetic model of foams, because the foam depends on the frequency against dynamic viscoelasticity. The 4 model-elements were calculated by experimental regression analysis, as a result, G₁=30 to 250dyn/cm², G₂=75 to 1000dyn/cm², γ₂=30 to 400 poise and γ₃=0 to 45 poise.
According to the relationship between sensory assessment valve (α-value) and rheological properties, sensory evaluation of being spread foam correlates with the characteristic values of the flow curves. Sensory assessment items, such as stiffness, which were evaluated immediately after touching the foams before macro-flow occurred, were related to the properties obtained from measuring the dynamic viscoelasticity, when the foams exhibited an infinitesimal deformation.