Method of making a large-diameter blow-molded container having a narrow mouth

Abstract

A preform or parison for manufacturing a container having a large interior diameter body and small interior diameter opening is prepared by molding the preform in two parts, a body having a generally cylindrical sidewall with one open end and one closed end, and a preform end having a diameter sized to mate with the sidewall and an opening therein for accessing the interior of the preform, and then joining the preform body and preform end to form a complete preform having an internal diameter larger than the diameter of the opening. The preform so formed is then used in a conventional blow molding process to produce a container having a large internal diameter and a narrow access opening.

We claim  
     
         1 . A preform for forming a container having a large diameter and a narrow mouth, said preform comprising a body having a sidewall with an internal diameter, a closed first end and a second end, said second end having an opening therein for accessing the interior of the preform, said opening having a diameter less than said internal diameter of said sidewall.  
     
     
         2 . The preform of  claim 1  wherein said sidewall has a generally cylindrical shape.  
     
     
         3 . A preform for forming a container having a large diameter and a narrow mouth, said preform having been prepared by a method comprising the steps of 
 providing a molded plastic preform end having an opening therein    providing a molded preform body having a circumferential side wall, a closed end and an open end,    joining said preform end to said open end of said preform body, and    expanding said preform body by blow-molding to form a container.    
     
     
         4 . The preform of  claim 3  wherein said preform is made from polyethylene.  
     
     
         5 . The preform of  claim 3  wherein said preform is made from polypropylene.  
     
     
         6 . The preform of  claim 3  wherein said preform is made from poly(ethylene terephthalate).  
     
     
         7 . The preform of  claim 3  wherein said preform is made from polycarbonate.