Texture Control of the Lipstick Film Using Rheological Technique and Commercialization of Liquid Rouge

Abstract

We have been focusing on an action peculiar to lips, and the new rheological approach to improve moisture feel for lipsticks was developed. It was revealed that the normal force difference in the high shear rate region was connected with moisture feel for lipsticks. It is widely known that the use of polymeric materials is effective to increase the normal force. However the control of spinnability has been a problem for ordinary polymers like polyether. A cellulose derivative with low spinnability has been developed. Spinnability and viscoelasticity were evaluated for a polyether (POE) and a long-alkyl acylated cellulose derivative (RCE). Since dynamic moduli of both samples could not be expressed with a single Maxwell mode, one of these samples is shifted by the correspondence of their tan d. The storage modulus, G′, of RCE with low spinnability is greater than that of POE with high spinnability. For the non-linear rheology, we found that the correspondence between the first normal stress coefficient, Ψ₁, and G′/ω² is different between two samples. POE with high spinnability has no correspondence of this relationship. We developed new liquid rouge with RCE with low spinnability. This liquid rouge came to have high moisture performance totally.