Abstract: A plastic injection mould capable of producing, at each injection, twenty articles numbered in serie and in high relief. The mould has a fixed plate (2) across which pass two pluralities or groups of tapes (13-18) numbered in mirror image, each plurality passing two series of numbers fixed on the plate. The fixed numbers corresponding to one of the pluralities of tapes are 0, 2, 4, 6, 8, 0, 2, 4, 6, 8 while the numbers corresponding to the other plurality are 1, 3, 5, 7, 9, 1, 3, 5, 7, 9. The tape (18) of each plurality that passes adjacent the fixed numbers contains an even number of series of ten groups of five identical algorisms (0, 0, 0, 0, 0; 1, 1, 1, 1, 1; 9, 9, 9, 9) whereas each of the other tapes contains at least one series of ten groups of ten identical algorisms (0, 0, 0, 0, 0, 0, 0, 0, 0, 0; . . . 9, 9, 9, 9, 9, 9, 9, 9, 9, 9).

Abstract: A security envelope for transporting confidential papers or money is disclosed having a high degree of security, being easy to close and seal as well as simple to manufacture. The envelope of the invention is provided with a closure and seal device having a first part extended along one side of the opening thereof, external of the envelope, such part being formed with a series of long pins distributed along its length. The pins pass through both sides of the envelope along a line adjacent to the opening to be received and locked in locking sockets formed in a second part extended along the opening on the other side of the envelope. The two parts of the closure and seal device are preferably hinged together along corresponding londitudinal edges so that when closed, the hinge lies along the opening so as to prevent access to the interior of the envelope through the spaces between the pins.

Abstract: A mold for injection molding of plastic articles which are automatically numbered or coded without repeating the combinations. In accordance with the invention one half of the mold comprises concentric rings rotatable about a reference axis perpendicular to the mold surface, the rings forming portions of the mold cavity in equally spaced positions about said reference axis, each ring presenting in the interior of each cavity a marking that is different from those that it presents to the other cavities, means for rotating one of said rings by increments so that its markings are presented, one by one, to said cavities, and for rotating each other ring by an increment each time the previous ring completes a revolution, in a manner similar to a mechanical counter, and actuating means to actuate said rotating means by an increment for each cycle of separation and approximation of said mold halves.