Dai Nippon Insatsu Kabushiki Kaisha

Dai Nippon Printing Co., Ltd.

Dai Nippon Insatsu K.k.

Shigeki Umise

Hirokatsu Imamura

Kyoichi Yamamoto

Masafumi Hayashi

Kenichiro Suto

Kouichi Nakamura

Hirokazu Kaneko

Yoshiaki Hida

Akira Mizobuchi

Kyohei Takahashi

Hiromi Watanabe

Taro Suzuki

Keiichi Ogawa

Hideichiro Takeda

Takeo Suzuki

Thermal transfer sheet

A co-winding type thermal transfer sheet is constituted by forming on one surface side of a substrate film a heat-fusible ink layer comprising a pigment and a particulate binder, and causing a tracing paper to be peelably bonded onto the heat-fusible ink layer by the medium of an adhesive layer. The thus constituted co-winding type thermal transfer sheet is capable of providing an original image which can be reproduced by use of a blueprint process so as to provide blueprint images having a high precision and a high contrast. In addition, a co-winding type thermal transfer sheet may also be constituted by forming a heat-fusible ink layer on one surface side of a substrate film and causing a transparent resin sheet to be peelably bonded onto the heat-fusible ink layer by the medium of an adhesive layer containing a cross-linking agent. The thus constituted co-winding type thermal transfer sheet is capable of providing an image excellent in wear resistance on the transparent resin sheet. The transparent resin sheet after the image formation may be used as an OHP (overhead projector) sheet without contaminating the sheet having no liquid absorbing property.

A co-winding type thermal transfer sheet is constituted by forming on one surface side of a substrate film a heat-fusible ink layer comprising a pigment and a particulate binder, and causing a tracing paper to be peelably bonded onto the heat-fusible ink layer by the medium of an adhesive layer. The thus constituted co-winding type thermal transfer sheet is capable of providing an original image which can be reproduced by use of a blueprint process so as to provide blueprint images having a high precision and a high contrast. In addition, a co-winding type thermal transfer sheet may also be constituted by forming a heat-fusible ink layer on one surface side of a substrate film and causing a transparent resin sheet to be peelably bonded onto the heat-fusible ink layer by the medium of an adhesive layer containing a cross-linking agent. The thus constituted co-winding type thermal transfer sheet is capable of providing an image excellent in wear resistance on the transparent resin sheet. The transparent resin sheet after the image formation may be used as an OHP (overhead projector) sheet. without contaminating the sheet having no liquid absorbing property.

A thermal transfer sheet having a back coating layer excellent in heat-resistance is provided by using a styrene-acrylonitrile copolymer as a resin constituting the back coating layer. A thermal transfer material having an excellent heat-resistance and having a back coating layer having considerable strength is provided by incorporating at least two species of heat-resistant particles having different particle sizes in the back coating layer, since the larger species of particle imparts excellent heat-resistance to the back coating layer, the smaller species of particle enhances the total amount of the fillers, and the larger and smaller species of particles function so as to provide a synergistic effect. A thermal transfer sheet having a back coating layer which is excellent in storability is provided by incorporation an alkylphosphate multi-valent metal salt into the back coating layer, since the thus prepared back coating layer has an excellent heat-resistance, does not contaminate another menber or thermal head without wearing the thermal head, and has an excellent slip property and an excellent dye barrier property.

A thermo-transfer sheet is composed of a base film and an ink layer to be transferred having a softening point of more than 120.degree. C. A label is formed by the thermo-transfer sheet and provided with an image ink layer formed on a thermo-transfer image receiving sheet through a temperature-sensitive adhesive layer and the image ink layer has a softening point of more than 120.degree. C. The thermo-transfer sheet and the thermo-transfer image receiving sheet are prepared and a temperature-sensitive adhesive layer is formed on at least one of the surface of the thermo-transfer sheet or the transfer ink layer of the thermo-transfer image receiving sheet. These sheets are laminated and the laminated sheets are heated by means of a thermal head to thereby transfer the image ink layer having a softening point of more than 120.degree. C. on the thermo-transfer image receiving sheet. According to these processes, a label such as bar code is manufactured with an excellent durability such as friction-proof property, solvent-proof property and heat-proof property.

Thermo-transfer sheet and label and manufacturing method of the same

A strip or roll of thermal transfer type recording sheet has a base film on one side of which a hot-melt ink layer is formed for recording on paper or other surface by thermal transfer. An end mark or marks to be detected optically for warning the user of the fact that the recording roll is being used up is/are formed adjacent one end of the strip by gravure printing with use of a light-reflective ink. The end mark or marks produced by gravure printing are of such constant thickness, and with the bounding edges so sharply defined, that they permit positive detection by an optical sensor. For the production of the end marks by gravure printing, a web of base film with the hot-melt ink layer formed on one side thereof, with a width several times greater than that of each strip of recording sheet to be manufactured, is fed through a printing unit of a gravure printing section. A set of end marks printed by the printing unit on the web in juxtaposition in its transverse direction are dried immediately, with the drying effect exerted only on the end marks. Then, while being still fed continuously, the web is slit at a slitting section into the required narrower strips of recording sheet each bearing one of the end marks. The separate strips of recording sheet are subsequently wound into rolls.

Apparatus for manufacturing strips of thermal transfer recording sheets

There is used, as a substrate film, a polypropylene film having a tear strength in the range of 15 to 40 Kg with respect to an MD direction and a TD direction thereof; an elongation in the range of 40 to 200 with respect to the MD direction and the TD direction thereof; and a Young's modulus in the range of 200 to 600 Kg/mm.sup.2 with respect to the MD direction and the TD direction thereof, and a transferable ink layer is formed on a surface of such a substrate film. When the resultant thermal transfer sheet having such a structure is used, a printing pressure based on a thermal head is sufficiently transmitted to a transfer receiving material, and therefore it is possible to form an image of good quality on the transfer receiving material even when the transfer receiving material comprises a plain paper having a relatively rough texture (or relatively coarse grain).

Thermo-transfer sheet

A heat transfer sheet comprising a base film and a hot melt ink layer formed on one surface of the base film, said hot melt ink layer comprising one or more components which impart filling to the printed areas of a transferable paper during transferring. Another type of a heat transfer sheet comprising a base film, a hot melt ink layer laminated on one surface of the base film, and a filling layer laminated on the hot melt ink layer, said filling layer comprising one or more components which impart filling to the printed areas of a transferable paper during transferring. According to the heat transfer sheets, high quality printing can be attained even at a high speed without any staining.

Heat transfer sheet

Method of manufacturing strips of thermal transfer recording sheets

A thermal transfer sheet has a substrate film, a heat-fusible ink layer formed on one surface side of the substrate film, and an antisticking layer formed on the other surface side of the substrate film. The heat-fusible ink layer comprises a carbon black having toluene-coloring transmittance of 60% or more, and, therefore, there is provided a thermal transfer sheet containing a heat-fusible ink layer having an uniform thickness and being capable of providing printed letters improved in blackness and durability such as solvent resistance.

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Tokyo, Japan

Shigeki Umise