Abstract: Disclosed is a process for making a preliminarily printed formed body, which is characterized in that a halftone separated rectangular printing plate is once made from a rectangular original, halftone dots of each halftone-separated image are developed on an annular plane by picture element units finer than the halftone dots to deform the shapes of the dots, an annular halftone dot image is formed based on the changes of the shapes of the halftone dots and a halftone printing plate for the annular halftone dot image is made, and this halftone printing plate is applied to a blank to be formed. According to this process undesirable formation of a striped pattern caused by the elongating flow of the blank in the height direction and the contracting flow of the blank in the circumferential direction is prevented and a strange feeling is not given to the printed image, and a faithful printed image can be reproduced.

Abstract: The present invention relates to a process for preparing a printed can be draw-forming or draw-redraw-forming a preliminarily printed metal blank or laminate. By forming an original plate for printing by an image processing by a computer, a print image faithful to the original image can be manifested on the side wall portion of the can, and formation of an undesirable stripe pattern can be prevented. Furthermore, a print image excellent in the linearity can be displayed without an error on the draw-formed can in due consideration of the anisotropy owing to the plastic flow of the blank.

Abstract: Disclosed is a method for preliminarily printing a blank for a tapered draw-formed body, which comprises transforming digital rectangular coordinates to annular coordinates so that the height of the rectangular coordinates is made to correspond to the height of a tapered plane on which the printed image is to be manifested and the change of the area of the tapered plane by a minute change of the height of the tapered plane is made equal to the change of the area of the annular plane. In this method, excessive flattening of the image in the lateral direction is prevented when the resulting preliminarily printed blank is draw-formed, and an image having a beautiful appearance and a high commercial value can be reproduced.

Abstract: Disclosed is a packing can having a circumferential polyhedral wall formed on a can barrel, in which as compared with boundary ridgelines of structural unit faces of the polyhedral wall and crossing points of these boundary ridgelines, the structural unit faces are convex to the interior of the can and the structural unit faces are arranged so that adjacent rows of structural unit faces have a phase difference in the axial direction of the can. This packing can has a very high strength against deformation by application of the external pressure. Furthermore, in preparing this packing can, damage of a coating layer formed on a metal sheet used as the can barrel blank can be effectively prevented.

Abstract: The present invention provides a redrawing method which comprises holding a preliminarily drawn cup of a covered metal sheet by an annular holding member inserted in the cup and a redrawing die, and relatively moving the redrawing die and a redrawing punch arranged coaxially with the holding member and redrawing cup, said drawing punch being capable of going into the holding member and coming out from the holding member, so that the redrawing die and redrawing punch are engaged with each other, to form a deep-drawn cup having a diameter smaller than that of the preliminarily drawn cup. This redrawing method is prominently characterized in that the radius of curvature of the operating corner portion of the redrawing die is 1 to 2.9 times as large as the bare sheet thickness of the metal sheet.

Abstract: Disclosed is a plastic cap comprising a top plate and a skirt hanging down from the peripheral edge of the top plate, which are integrally formed of a plastic material, and a mechanism for clamping the cap to a vessel, which is arranged on the inner circumferential face of the skirt, wherein a receiving seat to be substantially exactly engaged with the top edge or peripheral edge of the vessel mouth and at least one sealing projection protruding from the receiving seat through a groove by a very small distance from the face of the receiving seat are arranged in an inner corner portion between the top plate and the skirt or in the vicinity thereof, and sealing is effected by the pressure generated by compression deformation of the sealing projection. In this plastic cap, plastic deformation of the sealed portion is prevented and a high durable sealing pressure is obtained. Accordingly, this plastic cap has an excellent pressure-resistant sealing property and an excellent venting property in combination.

Abstract: The present invention provides a redrawing method which comprises holding a preliminarily drawn cup of a covered metal sheet by an annular holding member inserted in the cup and a redrawing die, and relatively moving the redrawing die and a redrawing punch arranged coaxially with the holding member and redrawing cup, the drawing punch being capable of going into the holding member and coming out from the holding member, so that the redrawing die and redrawing punch are engaged with each other, to form a deep-drawn cup having a diameter smaller than that of the preliminarily drawn cup. This redrawing method is prominently characterized in that the radius of curvature of the operating corner portion of the redrawing die is 1 to 2.9 times as large as the bare sheet thickness of the metal sheet.

Abstract: A process for the preparation of a printed draw-formed body having a printed image on the side wall thereof by subjecting a prior-printed blank to draw-forming, which comprises converting an image of an original to be printed to a digital image element signal on a rectangular coordinate, converting the image element signal on the rectangular coordinate to an image signal or image signals on a corresponding conversion coordinate formed by developing the rectangular coordinate to an annular plane having an area substantially equal to the area of said rectangle, reading image element signals on the conversion coordinate in order of the coordinate, photo-electrically converting the read image element signals to a printing plate for the blank and printing the blank by using the formed printing plate. According to this process, since digital coordinate conversion is performed while compensating anisotropy of the elongation of the metal blank, an improved printing precision can be obtained in a draw-formed body.