To provide simple and exact means for judging whether or not a component to be used for a head skin or head hair reaches a point of application and a method for evaluating sebum migration of a specimen.

This method evaluates sebum migration of a specimen with an index of migration degree of the specimen to an artificial sebum by making one surface of a thin film 12 similar to a skin surface come into contact with the specimen, with the other side surface thereof in contact with an artificial sebum. In this method one side of the thin film has an open system. The artificial sebum is a fluid state. The thin film is a single layer silicone film a surface of which is subjected to keratin treatment. The specimen is made to come into contact with the keratin treatment side of the film. An evaluation kit for evaluating migration of sebum comprises (1) a sealing portion of an artificial sebum, provided in an opening portion thereof with fixing means capable of fixing and covering detachably the thin film; (2) a thin film similar to a skin surface layer to be fixed on and cover the opening portion of the sealing portion; and (3) an artificial sebum to be sealed in the sealing portion. The head skin and head hair composition contains isostearyl alcohol as a skin migration acceleration component.