Measurement of surface properties

A method for accurate measurement of properties of a passive surface such as elasticity, the method comprising applying a probe so as to establish a pressure of predetermined value to said passive surface, adapted to result in changes in substantially only the surface layer to be measured, recording the change of level of the probe resulting from the application of said pressure to said passive surface, removing at least a portion of the predetermined pressure and recording the resulting change of said level.

A method for accurate measurement of surface properties such as elasticity which comprises applying a probe so as to establish a pressure of predetermined value to said surface, adapted to result in changes in substantially only the surface layer to be measured, recording the change of level of the probe resulting from the application of said pressure, removing the pressure and recording the resulting change of said level, and wherein the surface is the epidermis, and the pressure is applied of less than 20 g/cm.sup.2 probe area by a weight.

A method for the accurate measurement of surface properties such as elasticity which comprises applying a probe so as to establish a pressure of predetermined value to said surface, adapted to result in changes in substantially only the surface layer to be measured, recording the change of level of the probe resulting from the application of said pressure, removing the pressure and recording the resulting change of said level, and wherein the probe is applied by suction to the surface, properties of which are to be measured, a weight is applied in a direction tending to lift the probe from the surface, and the resulting change of level of the probe is recorded versus time.

A method for the accurate measurement of surface properties of human skin which comprises applying a probe so as to establish a pressure of predetermined value to said surface, adapted to result in changes in substantially only the surface layer to be measured, recording the change of level of the probe resulting from the application of said pressure, removing the pressure and recording the resulting change of said level, measured are compressibility, viscosity, elasticity, humidity and stretchability of the human skin.

A method for the accurate measurement of surface properties such as elasticity which comprises applying a probe so as to establish a pressure of predetermined value to said surface, adapted to result in changes in substantially only the surface layer to be measured, recording the change of level of the probe resulting from the application of said pressure, removing the pressure and recording the resulting change of said level, and wherein the measurement is carried out on human skin, said measurement being for evaluating the effects of cosmetic preparations on human skin, and which comprises additionally applying such preparation to human skin in vivo, and recording the surface properties of the skin at predetermined periods of time, comparing said properties before such application and at certain periods of time after such application.