Perforable container cap

Abstract

A perforable container cap that reseals after puncture by a sampling tube or needle. Embodiments of the container cap may include a container cap locking mechanism having a barb and adjacent stop both projecting downward from a cap edge to mesh with a V-shaped block projecting outward from a container sidewall.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is: 
     
         1 . A perforable container cap comprising:
 a cap having a top, perforable wall, and   an internally threaded annular flange formed integrally with said perforable wall and extending downwardly from said perforable wall to enclose a cavity open at a bottom end of said cap.   
     
     
         2 . A perforable container cap comprising:
 an annular side wall surrounding a cavity closed at a top end by an integral top wall, said top wall perforable by a relatively thin diameter, elongated, tubular sampling element; said side wall and said top wall substantially formed from a single molded piece.   
     
     
         3 . The perforable container cap of  claim 2 , wherein said top wall is of substantially uniform thickness. 
     
     
         4 . The perforable container cap of  claim 2 , wherein said top wall includes a perforation area of reduced thickness. 
     
     
         5 . The perforable container cap of  claim 2 , wherein said top wall includes a perforation area comprising material optimized to reseal after perforation. 
     
     
         6 . The perforable container cap of  claim 2 , wherein said top wall comprises a relatively soft and resilient plastic material. 
     
     
         7 . The perforable container cap of  claim 2 , wherein said top wall comprises a material selected from the group consisting of polyethylene, polypropylene, high density polyethylene, linear low density polyethylene, butyl rubber, silicon rubber, urethane and thermoplastic elastomer. 
     
     
         8 . The perforable container cap of  claim 2 , wherein said top wall comprises a primary layer of polyethylene and also a secondary layer comprising material selected from the group consisting of thermoplastic elastomer, urethane, silicon or butyl rubber, with one of said layers disposed over the other of said layers so that the layers are pierced concurrently or consecutively by a sampling element. 
     
     
         9 . A perforable container cap comprising:
 a cap having a top wall, and   an annular flange formed integrally with said top wall and extending downwardly from said top wall to enclose a cavity open at a bottom end of said cap,   said top wall and said annular flange molded to form a single piece, said top wall including a central aperture covered by a thin, pierceable membrane.   
     
     
         10 . The perforable container cap of  claim 9  wherein said membrane is integrated into said top wall by in-mold labeling. 
     
     
         11 . A method for producing an integral, perforable container cap comprising the steps of:
 positioning a thin membrane within a mold so that the membrane extends across the margins of an aperture to be molded in the top wall of a container cap;   injecting thermoplastic material into the mold to form the cap and to adhere or fuse to the membrane.   
     
     
         12 . The method of  claim 11  wherein said membrane comprises a thermoplastic material selected to melt sufficiently during molding to fuse with the thermoplastic material of the cap body. 
     
     
         13 . The method of  claim 11  wherein said membrane comprises a metal foil.