公开(公告)号：WO1985001011A1

公开(公告)日：1985-03-14

申请号：PCT/GB1984000275

申请日：1984-08-08

Applicant: METAL BOX P.L.C. ,  BROOKS, David, William

Inventor： METAL BOX P.L.C.

IPC: B29C49/10

CPC classification number: B29C49/14 ,  B29C49/0042 ,  B29C49/06 ,  B29C49/12 ,  B29C49/6472 ,  B29C2049/0089 ,  B29K2105/258

Abstract: A method of producing a tubular article, such as a can body or a bottle, of a biaxially oriented crystallisable thermoplastic polymer such as polyethylene terephthalate from a tubular article of smaller dimensions, such as a preform, having at least one open end, comprises heating the smaller tubular article to a temperature above the glass transition temperature but below the melting temperature of the polymer, stretching the tubular article axially by mechanical means such as an extending push rod (122) or a drawing chuk element, and simultaneously or sequentiall stretching the tubular article both axially and transversely by internal fluid pressure introduced through the open end (13), without any external mould or other external constraint. The stretched and biaxially oriented article (10) may be subsequently heated further to anneal the polymer and thereafter cooled before removal from the stretching apparatus, the internal pressure being reduced during such annealing and cooling. For polyethylene terephthalate, the stretching temperature is from 75oC to 120oC and the internal fluid pressure from 7 to 15 bars, while the annealing temperature is from 110oC to 240oC and the reduced internal fluid pressure used during annealing and/or cooling is from 2 to 4 bars.