One of the reasons may be that those products were packaged in high altitude areas such Colorado ( low pressure ) and brought to one of the coasts ( higher pressure ). The bottle is pressed in till the inside and outside pressures are equal. A 50 gallon metal tank can implode if it is attached to a vacuum pumped and air taken out. Regards, Ramon > -----Original Message----- > From: [log in to unmask] [SMTP:[log in to unmask]] > Sent: Wednesday, May 28, 2003 9:55 AM > To: [log in to unmask] > Subject: [TN] why do HDPE bottles get deformed? > > We've all seen them, High Density Polyethylene bottles that have become > all "sucked in", to the point where they're almost triangular. I have > bottles with rosin fluxes, and others with decap chemicals (Dynasolve > products) that have done this - all in their original containers. They've > been stored in an friendly environment, no strange temperatures or > anything unusual. Over the years I've seen many other products in poly > bottles do the same. The bottles seem to get very hard, and never recover > their original shape. Does anyone know what causes this? > > Bruce Tostevin > Benchmark Electronics > Hudson, New Hampshire > > --------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to > [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/html/forum.htm for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 > ext.5315 > ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------