2015 Volume 56 Issue 6 Pages 555-561
Few studies have been carried out on fiber assemblies such as cosmetic brushes, and thus there is a lack of objective evaluation. In order to perform objective evaluation, systems for measuring the mechanical properties and application properties of cosmetic brushes were devised. The systems were designed to simulate the actual usage of the brushes. A device for measuring mechanical properties was able to quantify the restoring force and the frictional force when bending a brush. The restoring force was the resultant of vertical and horizontal forces, and the frictional force was equivalent to the horizontal force. A device for measuring the application of foundation was created to take up and apply foundation to a skin model in controlled conditions. Sensory tests were then performed to consider how physical properties affected the usage of the brush. Results showed that the system could measure the physical properties of the brush, and suggested that there were correlations between vertical force and foundation quantity, and also correlations between horizontal force and softness.
