Abstract: A layer of ink containing a light absorbing heat generating substance is provided on the rear surface of a heat-sensitive plastic film of a thermal stencil sheet when the heat-sensitive plastic film is perforated by a laser beam. When a rotary stencil printer is used, a stencil sheet is mounted around a printing drum of the rotary stencil printer in a condition adhesively held by an ink layer, then a laser beam is irradiated to a portion of the stencil sheet to be perforated, and then the printing process is carried out with the stencil sheet as it has been mounted around the printing drum for the perforation.

Abstract: In a stencil printing including the steps of supplying ink in the form of a layer on one side of a perforated stencil sheet, contacting another side of the stencil sheet to a surface for printing, applying a pressure to the ink layer by a pressing means so as to transfer the ink of the ink layer through perforations of the stencil sheet from the one side to the other side of the stencil sheet and to attach the ink thus transferred onto the surface for printing, and detaching the surface for printing from the other side of the stencil sheet, the improvement is which the surface for printing is detached from the other side of the stencil sheet at a portion thereof where a movement of the ink layer relative to the stencil sheet is substantially impeded by the pressing means so that a drawing out of the ink from the ink layer onto the surface for printing due to the adhesiveness and viscosity of the ink does not occur when the surface for printing is detached from the stencil sheet, thus also allowing the extrusi

Abstract: A machine tool position correcting method and apparatus applied to a machine tool including a spindle head provided on a column and a ram which is movable horizontally on the spindle head and has a main shaft to which a tool is mountable. In the arrangement, a quantity of horizontal movement of the ram is detected, a quantity of vertical correction of the ram is calculated on the basis of the detected quantity of horizontal movement of the ram, and the spindle head is moved vertically, while keeping a horizontal position thereof, on the basis of the calculated quantity of vertical correction of the ram. Since a vertical deviation of the ram has a correction to its quantity of horizontal movement, the vertical deviation, or quantity of vertical correction, of the ram is obtained by detecting its quantity of horizontal movement.

Abstract: In a rotary stencil printer having a printing drum made of two annular members connected by a transverse bar member and a net member of woven, non-woven or knitted fibers of a rectangular shape in development wound around the two annular members with opposite side edge belt portions thereof being slidably laid on outer circumferential surfaces of the annular members so as to form a porous cylindrical body for mounting a stencil sheet as wound therearound, a back press roller of a diameter common with the printing drum disposed to face an outside surface of the printing drum so as to define a print sheet nip region with the printing drum therebetween and having a groove in an outside surface portion thereof adapted to receive the transverse bar member therein in meeting therewith in synchronized rotations of the printing drum and the back press roller in opposite directions, and an inner press roller disposed in an inside space of the printing drum so as to contact with an inside surface of the porous cylindri

Abstract: A thermal stencil sheet assembly of the type having an annular frame made of a cardboard and a thermal stencil sheet attached to one face of the frame as fixed thereto along an entire peripheral portion thereof with or without an ink pressing sheet made of an ink impermeable sheet attached to another face of the frame, wherein the frame is assembled of a first frame element made of a relatively thin sheet material and a second frame element made of a cardboard, the two frame elements being detachably and reattachably bound together by a slippery surface provided on the first frame element being attached to a layer of a sticky binding material provided on the second frame element.

Abstract: In a rotary stencil printer having a printing drum supported to be rotatable about a central axis thereof and having a cylindrical outer surface adapted to bear a perforated stencil sheet as attached therearound and formed with openings for supplying ink to an inside surface of the perforated stencil sheet, and a back press roller supported to be rotatable about a central axis thereof extending in parallel with the central axis of the printing drum and having a cylindrical outer surface which defines a nip area with the cylindrical outer surface of the printing drum therebetween for nipping and transferring a printing sheet therethrough.

Abstract: An exposure device for a thermal stencil sheet having a linear electronic flash discharge tube and an enclosure made of a plate member curved around the tube in a substantially cylindrical shape coaxial with the tube while defining a slit opening parallel to the tube, wherein a thermal stencil sheet is loaded into the enclosure through the slit opening and is supported in a substantially cylindrical shape coaxially around the tube for receiving direct infrared radiation from the tube with no interposition of a glass layer or the like.

Abstract: A stencil paper assembly comprising a stencil paper sheet and an ink-impermeable sheet laid one over the other, said assembly being adapted to maintain a layer of ink between said stencil sheet and said ink-impermeable sheet so that numerous printed sheets may be obtained with one charge of ink and without causing smearing of ink.