Abstract: A cigarette having thereon a reversible thermochromogenic portion which changes color at a temperature in the range of about 40.degree.-80.degree. C. on the surface except the free end area which makes contact with lips of a smoker, the portion including a thermochromogenic composition which comprises:(a) an electron donating organic compound as a chromogenic compound;(b) an aromatic compound having at least one phenolic hydroxyl, or at least one carboxyl connected directly to the aromatic nucleus, or both, or an metal salt of these, as a color developer; and(c) a desensitizer which melts at a temperature in the range of about 40.degree.-80.degree. C.Said thermochromogenic composition changes color reversibly at a temperature at or near the temperature at which the desensitizer melts.

Abstract: This invention provides an apparatus for indicating the electromotive force of a dry battery which comprises:(i) a film base;(ii) an electrically conductive layer disposed on one side of the film base,(iii) a protective layer disposed on the electrically conductive layer, and(iv) a thermochromic layer disposed on the other side of the film base.