Method of rotational molding about plural axes at low rotational speeds
US4104357A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 17, 1974 |
| Grant date | Aug 1, 1978 |
| Priority date | — |
| Expiry date | May 17, 1994 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C41/22
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Low speed rotational molding of plastic objects at about ambient temperatures from a liquid thermosetting plastic material distributed in a mold substantially under gravitational force; the selected thermosetting plastic is placed as a distributable liquid in a mold having a volume much larger than the volume of the liquid polymer and slowly rotated about two axes at or about room temperature; urethane polymers to which a quantity of diamine curing agent has been added prior to the introduction of the flowable plastic into the rotatable mold are typical thermosetting materials; useful objects or shapes having thin, relatively uniform walls are produced by the disclosed process; repetition of molding steps allows the build up of same or different layers which may have interposed therebetween, lightening, stiffening, and/or strengthening members; precoating of a mold with a variety of coatings which release, interact, or decorate the thermoset resin surface is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.