Abstract: A heat activation method for activating a thermosensitive adhesive label having a support and a thermosensitive adhesive layer which is provided on the support and is not adhesive at room temperature, so as to make the thermosensitive adhesive layer adhesive with the application of heat thereto, includes the step of heating the thermosensitive adhesive layer so as to make the thermosensitive adhesive layer adhesive by energizing a heater which is in contact with the thermosensitive adhesive layer, the heater having a heat-application portion which is constructed in such a fashion that a resistor and a protective layer are successively overlaid on a ceramic substrate. A heat activation apparatus has the above-mentioned heater, and a label printer for the thermosensitive adhesive label has a label holder, a printing apparatus, a cutter and a heat activator.

Abstract: A heat activation method for activating a thermosensitive adhesive label having a support and a thermosensitive adhesive layer which is formed on the support and is not adhesive at room temperature, so as to make the thermosensitive adhesive layer adhesive with the application of heat thereto, includes the step of bringing the thermosensitive adhesive layer into contact with a surface portion of a heating medium, at least the surface portion of the heating medium being made of a silicone resin and having a peel strength of 2 g/mm or less with respect to the thermosensitive adhesive layer. There is also disclosed a heat-activating apparatus for heat-activating the above-mentioned thermosensitive adhesive label.

Abstract: A heat activation method for activating a thermosensitive adhesive label having a support and a thermosensitive adhesive layer which is provided on the support and is not adhesive at room temperature, so as to make the thermosensitive adhesive layer adhesive with the application of heat thereto, includes the step of heating the thermosensitive adhesive layer so as to make the thermosensitive adhesive layer adhesive by energizing a heater which is in contact with the thermosensitive adhesive layer, the heater having a heat-application portion which is constructed in such a fashion that a resistor and a protective layer are successively overlaid on a ceramic substrate. A heat activation apparatus has the above-mentioned heater, and a label printer for the thermosensitive adhesive label has a label holder, a printing apparatus, a cutter and a heat activator.

Abstract: A thermosensitive recording label including a substrate, a thermosensitive coloring layer formed on one side of the substrate, and a thermosensitive adhesive layer which is formed on the opposite side of the substrate and which includes a thermoplastic resin and a tack applying agent and which is usually non-adhesive and becomes adhesive when activated by heat, wherein the thermoplastic resin includes a natural rubber which is graft-copolymerized with a vinyl monomer.

Abstract: A heat activation method for activating a thermosensitive adhesive label having a support and a thermosensitive adhesive layer which is provided on the support and is not adhesive at room temperature, so as to make the thermosensitive adhesive layer adhesive with the application of heat thereto, includes the step of heating the thermosensitive adhesive layer to make the thermosensitive adhesive layer adhesive while transporting the label along a heat-resistant transporting belt heated by a heater, with the thermosensitive adhesive layer being in pressure contact with the transporting belt using a pressure-application member. A heat activation apparatus is provided with a heat-application and transporting member and a pressure-application member. A label printer is provided with a label holder, a printing apparatus, a cutter and the above-mentioned heat activation apparatus.

Abstract: A thermosensitive recording adhesive label has a support, a thermosensitive coloring layer provided on one side of the support, and a thermosensitive adhesive layer which is formed on the other side of the support, opposite to the side of the thermosensitive coloring layer with respect to the support, and is adhesive above room temperature, with the thermosensitive coloring layer having a surface smoothness of 200 to 10,000 sec when measured by the method of Ohken-shiki prescribed in Japan Tappi No. 5, and the thermosensitive adhesive layer having a surface smoothness of 60 to 3,000 sec in terms of Bekk's smoothness.

Abstract: A heat activation method for activating a thermosensitive adhesive label having a support and a thermosensitive adhesive layer which is formed on the support and is not adhesive at room temperature, so as to make the thermosensitive adhesive layer adhesive with the application of heat thereto, includes the step of bringing the thermosensitive adhesive layer into contact with a surface portion of a heating medium, at least the surface portion of the heating medium being made of a silicone resin and having a peel strength of 2 g/mm or less with respect to the thermosensitive adhesive layer. There is also disclosed a heat-activating apparatus for heat-activating the above-mentioned thermosensitive adhesive label.

Abstract: A thermosensitive recording material comprising (a) a support, and (b) a thermosensitive recording layer formed on the support, comprising a leuco dye and a color developing agent comprising a metal salt or metal complex of a compound having formula (I), which is capable of inducing color formation in the leuco dye upon application of heat thereto: ##STR1## wherein X represents a halogen, an alkyl group having 1 to 10 carbon atoms, or an alkoxyl group having 1 to 10 carbon atoms; R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 independently represent hydrogen, a halogen, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 10 carbon atoms, an aralkyloxyl group having 7 to 20 carbon atoms, an aryloxyl group having 6 to 20 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aralkylthio group having 6 to 20 carbon atoms or an arylthio group having 6 to 20 carbon atoms, R.sup.1 and R.sup.2, or R.sup.2 and R.sup.