Abstract: A stencil printing machine is provided with a printing drum and a second printing drum. The stencil printing machine makes first and second stencil having first and second images perforated, winds the first and second stencil sheets around the first and second printing drums respectively, and presses print sheets on the first and second printing drums. The stencil printing machine includes a controller for performing a printing operation of firstly allowing the first printing drum to print the first printed sheets by a required number per one class and subsequently allowing either the second printing drum only or the first and second printing drums to print a single second printed sheet or the required number of second printed sheets. This printing operation is carried out by the controller, with respect to each class.

Abstract: A stencil printing machine is provided with a printing drum and a second printing drum. The stencil printing machine makes first and second stencil having first and second images perforated, winds the first and second stencil sheets around the first and second printing drums respectively, and presses print sheets on the first and second printing drums. The stencil printing machine includes a controller for performing a printing operation of firstly allowing the first printing drum to print the first printed sheets by a required number per one class and subsequently allowing either the second printing drum only or the first and second printing drums to print a single second printed sheet or the required number of second printed sheets. This printing operation is carried out by the controller, with respect to each class.

Abstract: A developing system for an electrostatic copying apparatus has a primary spiral screw for conveying developer (including at least toner) in one direction with respect to the width of an area to be developed, and a secondary spiral screw arranged for receiving developers from the primary spiral screw and for conveying the received developers in a direction opposite to the conveyance direction of the primary spiral screw. The primary and secondary spiral screws have different conveyance capacities. An apertured receptacle mounted below the primary spiral screw feeds developers from the primary spiral screw to the secondary spiral screw.

Abstract: The present invention relates to developing unit for an electrostatic reproducing apparatus, and more particularly to the developing unit comprising a developer mixing device thereof by which the developer is mixed up inside the developing unit in order to develop an electrostatic latent image.

Abstract: A magnetic-brush developing device wherein a rotary sleeve with permanent magnet incorporated therein is positioned inside a housing containing a developer, wherein the thickness of ears of developer formed on the peripheral surface of the rotary sleeve is regulated by a doctor blade, and wherein a rotor which forcibly removes surplus developer scraped off by the doctor blade is provided just in front of the doctor blade. The doctor blade regulating the thickness of ears of developer formed on the peripheral surface of the rotary sleeve with the permanent magnets incorporated therein is formed in the shape of a knife edge directed in the opposite direction to the direction of rotation of the rotary sleeve.

Abstract: In the process for preparing impregnated polymer latex compositions by impregnating a hydrophobic substance in dispersed polymer particles in an aqueous polymer latex, the improvement comprises impregnating said hydrophobic substance, wherein the impregnation is effected by mixing said hydrophobic substance which is solid state, a water-miscible organic solvent and aqueous polymer latex wherein a polymer of the polymer latex is prepared from ethene monomers and containing at least one hydrophilic group.