Riso Kagaku Corporation

Shoichi Ikejima

Jun Nakamura

Takanori Hasegawa

Tetsu Yamanaka

Kenichi Shibuya

Takeshi Koishihara

Satoshi Chonan

Hiromichi Yamada

Satoshi Nagashima

Stencil plate having independent dot perforations

Stencil plate

Method for producing a stencil plate from a heat sensitive stencil sheet

Method for producing a stencil plate

There is provided a water-in-oil (W/O) emulsion ink for stencil printing having an oil phase and a water phase, the oil phase containing a reaction product of an alkyd resin or a rosin-modified resin with an aluminum chelate compound or an aluminum alcoholate. Preferably, the reaction is carried out by heating the aluminum chelate compound or aluminum alcoholate with the alkyd resin or rosin-modified resin to a temperature enough to lower the acid value of the resin to 10 or less, and the reaction is carried out in the presence of a higher fatty acid or a higher alcohol in an amount of 0.5-2.5 mols per 1 mol of on the aluminum chelate compound or aluminum alcoholate. This emulsion ink is improved in storage stability and inhibited from increase of viscosity of the ink after the ink is left, and restarting of printing after suspension of operation of the printing machine can be satisfactorily performed.

Emulsion ink for stencil printing

A heat-sensitive stencil sheet consisting of a porous substrate and a thermoplastic film adhered to the substrate is provided without no use of an adhesive. The porous substrate comprises a screen cloth wholly or partially consisting of conjugate fibers (a sheath-core type or a side-by-side type) one exposed component of which has an affinity with the thermoplastic resin film and having a melting point lower than that of the other component of the conjugate fiber and lower than that of the thermoplastic resin, and the screen cloth is adhered to the thermoplastic resin film through the exposed component. The heat-sensitive stencil sheet can be produced by superposing the thermoplastic resin film on the substrate and heating under pressure the superposed film and substrate at the softening point or higher of the above exposed component of the conjugate fiber and at a temperature lower than the melting point of the other component of the conjugate fiber and lower than the melting point of the thermoplastic resin.

Process for producing a heat sensitive stencil sheet

Heat-sensitive stencil sheets and process

A process for producing a thermal stencil master sheet for stencil printing, which sheet, even when a thermoplastic film affording superior perforation properties but having low mechanical strengths is used therefor, can prevent the film from being broken to thereby improve its productivity is provided, which process comprises a step of laminating thermoplastic films onto both the surfaces of a base film, a step of bonding porous substrates onto the thermoplastic films and a step of stripping the thermoplastic films bonded to the porous substrates from the base film.

Process for producing a thermal stencil master sheet for stencil printing

An apparatus for disposing of a used thermal stencil master sheet, in a superior disposing efficiency and secret-retainability, and a process for disposing of the same are provided, which apparatus is provided with a stripping nail for stripping a used thermal stencil master sheet wound up on a stencil body therefrom, a waste stencil box for encasing the stripped master sheet and rolls for waste stencil for feeding the master sheet into the box, and is characterized by providing a means for heating the master sheet so that it is heat-shrinked and/or melted within the box, and which process comprises discarding the used master sheet of a thermal stencil master sheet, and heating the used master sheet so as to subject it to heat-shrinkage and/or melting.

Apparatus for disposing of a used thermal stencil master sheet and a

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Ibaraki-ken, Japan

Shoichi Ikejima