Method for producing display sign panel
US4053340A · kind A · utility
5Cited by
9References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 26, 1976 |
| Grant date | Oct 11, 1977 |
| Priority date | — |
| Expiry date | Jul 26, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T156/1056
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for producing a panel for a back-lighted display sign comprises the steps of impressing recesses about one surface of a planar sheet of rigid foam to reduce the sheet thickness in a pattern corresponding to a desired pattern of recesses. Apertures are also formed through the sheet at locations each bounded by an identical corresponding portion of each recess. The sheet of foam is then sandwiched between outer cover layers to complete the basic panel structure for a display sign having multiple recesses containing discs which are moved between bi-stable positions covering the apertues or clear of the apertures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.