Plastic and nonmetallic article shaping or treating: processes – Reactive gas or vapor treatment of work – Work is organic material
Patent
1993-07-13
1995-03-28
Timm, Catherine
Plastic and nonmetallic article shaping or treating: processes
Reactive gas or vapor treatment of work
Work is organic material
264526, 264529, B29C 4918, B29C 4946
Patent
active
054014514
ABSTRACT:
The present invention discloses an improved process for producing plastic containers with excellent resistance to permeation by solvents such as hydrocarbons, hydrocarbon fuels, and hydrocarbon fuels with organic additives including lower alkanols and ethers consistently and reliably. The process is related to a multi-step treatment of plastic containers in a controlled manner with fluorine containing gases while blow molding them. In the process of the present invention, a parison is formed from a pre-heated thermoplastic material, expanded within a closed mold by means of an inflating gas for conforming the parison to the shape of the mold, and subjected to multiple fluorination treatment steps to effect fluorination of the interior surface of the parison. In the first step of the multi-step fluorination treatment the parison is pressurized with a reactive gas containing from about 0.05 to about 0.54% fluorine by volume while the parison is at a temperature above its self supporting temperature and for a time sufficient to effect fluorination of the interior surface of the parison. Subsequently, the interior surface of the pre-fluorinated parison is pressurized with a reactive gas containing fluorine in a concentration that is greater than that used in the initial fluorination step for a time sufficient to form said fluorinated parison with excellent resistance to solvent permeation. The parison is purged with an inert gas, vented and the container recovered. The key requirements for producing containers with excellent resistance to solvent permeation consistently and reliably include (1) minimizing and/or eliminating the molecular oxygen contaminant in the parison while treating it with fluorine containing reactive gas and (2) selecting the concentration of fluorine in the reactive gas for the first and subsequent fluorination treatment steps in such a way that it eliminates both under and over fluorination of the inside surface of the parison.
REFERENCES:
patent: 4142032 (1979-02-01), D'Angelo
patent: 4264750 (1981-04-01), Anand et al.
patent: 4404256 (1983-09-01), Anand et al.
patent: 4593050 (1986-06-01), Cohen et al.
patent: 4617077 (1986-10-01), Giese et al.
patent: 4701290 (1987-10-01), Eschwey et al.
patent: 4830810 (1989-06-01), Ufer et al.
patent: 4869859 (1989-09-01), Eschwey et al.
patent: 5073231 (1991-12-01), Eschwey et al.
patent: 5213734 (1993-05-01), Masson et al.
patent: 5244615 (1993-09-01), Hobbs
Garg Diwakar
Hobbs John P.
Meixner Donald L.
Air Products and Chemicals Inc.
Bongiorno Mary E.
Brewer Russell L.
Marsh William F.
Timm Catherine
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