Conveyor lubricant, passivation of a thermoplastic container to stress cracking, and thermoplastics stress crack inhibitor
US6806240B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 2002 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Jun 14, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/38
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Thermally formed thermoplastic articles can be protected from stress cracking in the presence of stress cracking promoting compounds by forming a shaped article comprising a thermoplastic and a liquid hydrocarbon oil composition. We have found that the liquid hydrocarbon oil composition prevents the stress cracking promoting materials from interacting with the polymeric structure of the stressed container to prevent or inhibit stress cracking in such materials. The methods and compositions of the invention are particularly useful in preventing stress cracking in polyethylene terephthalate beverage containers during bottling operations during which the bottle in contacted with aqueous and non-aqueous materials such as cleaners and lubricants that can interact with the polyester to cause stress cracking particularly in the container base. A process for lubricating a container, such as a beverage container, or a conveyor for containers, by applying to the container or conveyor, a thin continuous, substantially non-dripping layer of a liquid lubricant. The process provides many advantages compared to the use of a conventional dilute aqueous lubricant.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.