Reverse write erasable paper
US7811741B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 24, 2009 |
| Grant date | Oct 12, 2010 |
| Priority date | — |
| Expiry date | Feb 24, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C1/73
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image-forming medium and methods for forming and imaging the medium are provided. The disclosed medium can be strongly colored under room illumination (or deliberate UV) and can be selectively discolored at an appropriate light wavelength to form an image. In one embodiment, the image-forming medium can include a substrate (e.g., a sheet of paper), a photochromic material incorporated with the substrate, and a photo-absorbing material incorporated with the photochromic material. Exemplary methods for using the image-forming medium to make a transient image can include first forming the image-forming medium by applying a coating solution containing photochromic material to the substrate or paper. The image-forming medium can have a medium color and can then be selectively exposed to a radiation through a mask to convert the photochromic material from a colored form to a colorless form and thus to form an image having a color contrast with its background.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.