Reduced warp paperboard tray
US5377903A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1994 |
| Grant date | Jan 3, 1995 |
| Priority date | — |
| Expiry date | Jun 16, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S229/931
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A paperboard tray which resists warping is formed of a unitary blank, the blank having a polymer coating on its tray interior forming surface. The polymer coating is typically a heat resistant, non-stick, FDA approved polymer applied by extrusion coating. The upstanding sidewalls of the tray are joined to respective peripheral portions of the tray base through curved score lines on the tray interior surface. Curved cut lines on the exterior tray surface are each aligned with respective curved score lines on the tray interior surface, the cut lines extending 75 to 90 percent through the blank. The curved score lines and their complementary cut lines may be curved either convex outwardly or concavely inwardly with respect to the tray base.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.