A method of manufacturing a phenol product having a reduced concentration of a contaminating reaction by-product. The display of the handheld device is linked to that of the underlying computer and file and directory icons together with their underlying files are copied to the handheld device. Each of the corner connectors is configured to receive at least one post. The pulse wave measuring apparatus can calculate an AI value or the like that is the characteristic value of a pulse wave using such characteristic points and calculation equation of each waveform. The invention further relates to a decorative skin having a weakened area. The invention also relates to methods for producing these inhibitors.