Tube of tamperproof construction and process for making same
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a tamperproof closure for a tube containing liquid, pasty or powdery material, especially pharmaceutical agents, on whose neck is molded a breakoff neck projection closing an output opening, which is engaged nonpositively or positively with a slipped-on cap. 
     2. Background Considerations 
     A container with a breakoff closure for receiving and metered dispensing of liquid, pasty or powdery material, for example, pharmaceutical agents, is known from DE-PS 26 53 993. With the known container, on the front end of the container neck a breakoff neck projection is molded with a preshaped recessed predetermined, breaking point to provide a tightly closed covering for the outlet opening. In addition, a cap that can be slipped on the front end of the neck is provided. After the first use, this container can again be closed with the cap, which is held to the container either by a locking engagement or a press fit. The manipulation of a second or other subsequent opening and the necessary expenditure of force are the same as in the first opening, so that the user cannot determine whether the container still has the original closure. 
     In the removal of certain materials, especially pharmaceutical agents, from containers, a tamperproof closure, i.e., a definite indication for the user that the container has not yet been opened, is often necessary. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to make available a simple tamperproof closure for tubes of the above-described type. 
     According to the invention, this object is achieved by a tamperproof closure on a tube for liquid, pasty or powdery material, especially pharmaceutical agents, on whose neck is molded a breakoff neck projection closing an output opening, which is engaged nonpositively or positively with a slip-on cap, wherein after the filling and closing the tube 
     a section of a neck projection or a projection formed on the latter is guided through an opening made in the cap, and is thereafter deformed to form a flange engaging over an edge of opening (6), 
     The tube for liquid, pasty or powdery material, especially pharmaceutical agents, on whose neck is molded a breakoff neck projection closing an output opening, which is engaged nonpositively and positively with a slip-on cap includes a, 
     cap that has an opening in the front and a neck projection that includes a section or projection projecting from the opening of the cap. 
     A positive connection between the neck projection of the tube and the cap slipped on the tube is advantageously produced by the process according to the invention. It is necessary only to make an opening on the front of the cap, i.e., to open the previously closed sleeve section of the cap, which receive the neck projection nonpositively or positively, and to guide a section of the neck projection or a projection formed on the latter through the opening thus resulting. Then, a deformation of this section or projection takes place to form a flange engaging over the edge of the opening. In this way, a positive connection is produced which resembles a rivet joint. 
     If the tube is opened by the breaking off of the neck projection, the cap can indeed be slipped again on the neck of the tube, but the neck immediately detaches from the tube neck. When grasped, so that the user knows that this tube had already been opened. This is important for sanitation purposes since the tube has for one of its uses anal application of pharmaceutical preparation. 
     Advantageously, a tube whose cap exhibits an opening in the front is used to perform the process. The sleeve section of the cap receiving the neck projection nonpositively or positively, is made as a sleeve open on both sides. The neck projection includes a section or projection projecting from this opening of the slip-on cap. In one embodiment, the neck projection is longer than the sleeve section on the cap receiving the neck projection. In another embodiment, a nipple-type projection is made on the neck projection, which extends through the opening of the slip-on cap. 
     It is especially advantageous to use the process according to the invention in tubes whose neck is designed as a rectal cannula. With these tubes, the tube body with special advantage consists of a laminate, especially an Al/PE laminate and has a molded-on or incorporated neck. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An embodiment of the invention is to be explained with reference to the figures of the drawing. There are shown in: 
     FIG. 1a--a side, sectional view of a tube, 
     FIG. 1b--a top view of a neck projection on the tube, 
     FIG. 1c is an enlarged portion of the tube wall shown in cross-section 
     FIG. 2a--a side sectional view of a cap, 
     FIG. 2b--a top view of the cap of FIG. 2a, 
     FIG. 3 a sectional view of a tube with a slipped-on cap, in which a part of the neck projection has been broken away, and 
     FIG. 4 a tube with the tamperproof closure produced according to the invention. 
    
    
     DETAILED DESCRIPTION 
     A tube 1 is represented in FIG. 1a. This tube 1 consists of a laminate (FIG. 1c), especially of an Al/PE laminate. A neck 2 is incorporated in this tube in the represented embodiment. This neck 2 is designed as a rectal cannula. 
     A neck projection 3 is molded-on to form a predetermined breaking point or frangible 9 on neck 2. This neck projection 3 closes the mouth of neck 2 with the frangible. Neck portion 3 includes a toothin 10 made on its periphery. 
     In FIG. 2a in addition to tube 1 represented in FIG. 1a, a cap 5 is represented relative to the tube at a level which the cap 5 occupies in the slipped-on position on tube 1. 
     Cap 5 includes a sleeve section 11, in which an inside toothing 12 is made. If, as FIG. 3 shows, cap 5 is slipped on neck 2 of tube 1, section 4, represented in FIG. 1a of neck projection 3 projects from opening 6 at the upper end of sleeve section 11. When cap 5 is slipped on neck 2, toothings 10 and 12 engage with one another, so that a positive, torsion-resistant connection is provided. The sleeve 11 is secured within the cap 5 by an annular flange 13 and is spaced from the cap by an annular gap 14. 
     By a deformation of section 4 of neck projection 3 represented in FIGS. 1 and 3, flange 8 represented in FIG. 4, which engaged over edge 7 at opening 6 or on sleeve section 11, is formed. In this way, a rivet-type connection between cap 5 and neck 2 or neck projection 3 is produced. This rivet-type connection assures, on the one hand, a secure fit of cap 5 on tube 1, as long as tube 1 has never been opened. On the other hand, this rivet connection makes it possible to configure the fit of cap 5 on neck 2 so loose that after breaking open the tube by twisting off neck projection 3, cap 5 can again be slipped-on loosely on the neck. However, since the cap 5 is detachable immediately from the tube 1 in the case of an attempted reuse, an indication is given to the user or another person that tube 1 has already been opened once. This is an important sanitary consideration since a tube used by one patient should not be used by another.