Reduced application energy closure

Abstract

Closure caps having a tamper evident band are disclosed. The tamper-evident band includes an angled top surface and an outer surface with notch therein. The closure cap allows for a reduction in the energy required for application to the container and reduced likelihood of premature bridge breakage.

What is claimed:  
     
         1 . A closure cap comprising a shell having an end panel and a downwardly depending skirt terminating in a terminal end, said closure cap further comprising: 
 a cylindrical, tamper evident band attached to said terminal end of said skirt by a plurality of frangible connectors;    said band including a top surface, a bottom surface and inner and outer surfaces,    wherein said top surface is downwardly tapered in the direction of said outer surface;    said inner surface including an inwardly extending bead;    said outer surface including a notch therein, said notch being generally axially oppositely disposed relative to at least a portion of said bead.    
     
     
         2 . The closure cap of  claim 1  wherein said downwardly tapered top surface slopes downwardly at an angle greater than 0 degrees.  
     
     
         3 . The closure cap of  claim 1  wherein said downwardly tapered top surface slopes downwardly at an angle of at least approximately 6 degrees.  
     
     
         4 . The closure cap of  claim 3  wherein said downwardly tapered top surface slopes downwardly at an angle of at least approximately 15 degrees.  
     
     
         5 . The closure cap of  claim 1  wherein said frangible members are substantially uniform in width.  
     
     
         6 . The closure cap of  claim 1  wherein terminal skirt end and said band define a circumferential gap.  
     
     
         7 . The closure cap of  claim 6  wherein said gap is of non-uniform height.  
     
     
         8 . The closure cap of  claim 7  wherein circumferential gap includes windows spaced between said downwardly tapered top surfaces.  
     
     
         9 . The closure cap of  claim 8  wherein said frangible members connect said band to said skirt within said windows.  
     
     
         10 . The closure of  claim 1  wherein said notch comprises a concave, smooth groove in said outer surface.  
     
     
         11 . The closure of  claim 1  wherein the thickness of said band between said inner and outer surfaces is non-uniform.  
     
     
         12 . The closure of  claim 10  wherein the thickness of said band between said inner and outer surfaces is non-uniform.  
     
     
         13 . The closure cap of  claim 12  wherein the thickness of said band is at a minimum in the region near the top plane of said bead.  
     
     
         14 . The closure cap of  claim 1  wherein at least said band is made of a plastic material.  
     
     
         15 . The closure cap of  claim 14  is made of a thermoplastic material.  
     
     
         16 . The closure cap of  claim 15  wherein said thermoplastic material comprises polypropylene or copolymers thereof.  
     
     
         17 . The closure cap of  claim 16  wherein said thermoplastic material comprises an impact copolymer of polypropylene and at least one other polyolefin.  
     
     
         18 . The closure cap of  claim 17  wherein said impact copolymer has an Izod impact notched at 23 degrees C. of at least approximately 1.8 ft.-lb./in.  
     
     
         19 . The closure cap of  claim 17  wherein said impact copolymer has a tensile strength at yield of approximately 2,900 to 3,700 psi, and a flexural modulus of approximately 130,000 to 160,000 psi.  
     
     
         20 . The closure cap of  claim 16  wherein said material comprises a polypropylene homopolymer with an Izod Impact at 23° of approximately 0.6 to 2.0 ft. lb./in.  
     
     
         21 . The closure cap of  claim 20  wherein said polypropylene homopolymer has a tensile strength at yield of approximately 4,400 to 5,700 psi and a flexural modulus of approximately 200,000 to 300,000 psi.