Abstract: A cylinder block plating apparatus preplates or plates a cylinder bore of each cylinder in a cylinder block of a multi-cylinder engine using a process liquid introduced into the cylinder bore in a condition of sealing an end of the cylinder bore when a communication hole is formed at the end of the cylinder bore, the cylinder block plating apparatus includes a sealing jig including a sealing unit including a cylinder bore seal for sealing the end of an inner peripheral surface of the cylinder bore and a communication hole seal for sealing a portion, near a communication hole, opposite to the cylinder inner peripheral surface, and a clamping unit disposed in the sealing unit to be pushed open and adapted to cause the communication hole seal to seal the portion located on the opposite side of the cylinder bore near the communication hole.

Abstract: A cylinder block plating apparatus preplates or plates a cylinder bore of each cylinder in a cylinder block of a multi-cylinder engine using a process liquid introduced into the cylinder bore in a condition of sealing an end of the cylinder bore when a communication hole is formed at the end of the cylinder bore, the cylinder block plating apparatus includes a sealing jig including a sealing unit including a cylinder bore seal for sealing the end of an inner peripheral surface of the cylinder bore and a communication hole seal for sealing a portion, near a communication hole, opposite to the cylinder inner peripheral surface, and a clamping unit disposed in the sealing unit to be pushed open and adapted to cause the communication hole seal to seal the portion located on the opposite side of the cylinder bore near the communication hole.

Abstract: An electrostatic capacitance type information signal recording disc comprises a laminated plate made up of a first sheet which is made from an inexpensive conductive or non-conductive material and is used as a core material and a second sheet which is made from a conductive material and is bound on at least one surface of the first sheet, and variations in geometrical configuration formed on the second sheet in accordance with information signals which are to be recorded. A method of manufacturing the disc comprises the steps of binding the second sheet on at least one surface of the first sheet so as to obtain a laminated sheet, cutting the laminated sheet into a plurality of laminated plates having a predetermined size, and compression molding the variations in geometrical configuration, in accordance with information signals which are to be recorded, on a recording part of the second sheet of each of the laminated plates supplied in succession.

Abstract: An information signal recording medium comprises a core material made of a non-conductive material, and a surface material made of a conductive material and in close adherence with at least one surface of the core material. Variations in geometrical configuration in accordance with information signals to be recorded on the recording medium are compression molded on the surface material. The materials constituting the surface material and the core material are selected so that a ratio V.sub.C /V.sub.N between a melt viscosity V.sub.C of the surface material and a melt viscosity V.sub.N of the core material at a temperature and a shear rate at the time of the compression molding is less than or approximately equal to 1.6.

Abstract: A disc accommodating case comprises an opaque jacket having an opening portion at one end thereof, for accommodating a disc recorded with information signals within an internal space formed in the jacket, and a member for closing the opening portion of the jacket accommodating the disc. The disc is provided with a display portion for displaying the surface side of the disc, at a predetermined position thereof. The jacket has a display window provided at a position opposing a part of the display portion of the disc accommodated within the jacket, for enabling the part of the display portion to be seen through the display window from outside the jacket.