Ricoh Company, Ltd.

Keiichi Maruta

Yukihiro Yuyama

Takashi Ueda

Hiroshi Yaguchi

Susumu Iwata

Yasuhiko Watanabe

A thermal-recording label includes a supporting body, a thermal coloring layer on one side of the supporting body, and a thermal adhesive layer on the other side of the supporting body, which thermal adhesive layer includes an infrared absorption substance.

Thermal recording label

A thermosensitive recording material is disclosed, which comprises (a) a support material; (b) a first thermosensitive coloring layer which comprises a first colorless or light-colored leuco dye having formula (I), ##STR1## and a first color developer having formula (II) capable of inducing color formation in said first leuco dye upon application of heat thereto; ##STR2## (c) a second thermosensitive coloring layer which comprises at least a second leuco dye having formula (III), ##STR3## the first and second thermosensitive coloring layers being formed on the support.

Thermosensitive recording material

A thermosensitive recording material is disclosed, which comprises (a) a support, (b) an undercoat layer formed on the support, which comprises spherical hollow particles made of a plastic material having a glass transition temperature ranging from 40.degree. C. to 90.degree. C., the spherical hollow particles having a mean particle diameter of 0.20 .mu.m to 1.5 .mu.m, and a voidage of 40% to 90%, and a binder resin in an effective amount, and (c) a thermosensitive coloring layer formed on the undercoat layer, which comprises as the main components a leuco dye and a color developer capable of inducing color formation in the leuco dye upon application of heat thereto.

A thermosensitive recording material comprising a support material and a thermosensitive coloring layer formed on said support material, said thermosensitive coloring layer comprising a colorless or light-colored leuco dye and a color developer capable of inducing color formation in said leuco dye upon application of heat thereto, the improvement wherein said leuco dye is a compound having general formula (I), ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each represent hydrogen or an alkyl group having a substituent, R.sup.5 and R.sup.6 each represent hydrogen or a phenyl group which may have a substituent, and R.sup.7 represents an alkyl group which may have a substituent or a phenyl group which may have a substituent, and said color developer is a compound having general formula (II), ##STR2## wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms.

A thermosensitive recording material is disclosed suitable for use in thermosensitive-recording-type tickets, including magnetic tickets, and thermosensitive-recording-type labels, comprising a support material; a thermosensitive coloring layer formed on the front side of the support material, which thermosensitive coloring layer comprises a leuco dye and an acidic material capable of coloring the leuco dye when heat is applied thereto; and a protective layer formed on the thermosensitive coloring layer, which protective layer comprises a polyvinyl alcohol with a saponification ratio ranging from 70% to 85% and is capable of preventing intrusion of materials which may discolor the thermosensitive coloring layer.

A thermosensitive-recording-type label sheet comprising a support material; a thermosensitive coloring layer formed on the front side of the support material, the thermosensitive coloring layer comprising a leuco dye and an acidic material capable of coloring the leuco dye when heat is applied thereto; and a barrier layer formed on the back side of said support material, opposite to the thermosensitive coloring layer, the barrier layer comprising a water-soluble polymeric material and a water-repellent wax or wax-like material and capable of preventing intrusion into the thermosensitive coloring layer of materials which may discolor the thermosensitive coloring layer; and an adhesive layer formed on said barrier layer. In this label sheet, the wax or wax-like material contained in the barrier layer plays an important role of protecting the thermosensitive coloring layer during the production of the label sheet as well as while in use.

Thermosensitive-recording-type label sheet

A releasable heat-sensitive recording paper is disclosed wherein a heat-sensitive color forming layer and a protective layer are laminated in succession on the surface of a substrate, said color forming layer consisting essentially of a leuco dye and an acidic substance, said protective layer consisting essentially of a water soluble resin, and further a required pattern is printed on this protective layer with an ultraviolet setting type printing ink, while a pressure-sensitive adhesive layer is formed on the back of the substrate and the thus formed layer is covered with a releasable paper.

Released heat-sensitive recording paper

A thermosensitive recording adhesive label comprising: a support sheet; a thermosensitive coloring layer formed on the front side of the support sheet, the thermosensitive coloring layer comprising a colorless or light-colored leuco dye and an acidic material capable of coloring the leuco dye when heat is applied thereto; a front barrier layer formed on the thermosensitive coloring layer, the front barrier layer comprising a polymeric material capable of preventing intrusion of materials which may discolor said thermosensitive coloring layer; a back barrier layer formed on the back side of the support sheet, the back barrier layer comprising a polymeric material capable of preventing intrusion of materials which may discolor the thermosensitive coloring layer; an adhesive layer formed on the back barrier layer; and a disposable backing sheet which is attached to the adhesive layer and can be peeled off the adhesive layer when the thermosensitive recording adhesive label is used.

Growing community of inventors

Numazu, Japan

Keiichi Maruta