Process for producing color change devices incorporating latent indicia and the resulting devices
US5062928A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 17, 1990 |
| Grant date | Nov 5, 1991 |
| Priority date | — |
| Expiry date | Apr 17, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65D2401/00
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A process for producing color change devices incorporating latent indicia and color change devices incorporating latent indicia produced by the process. The process involves anodizing a color generating metal, having limited surface areas thereof covered by a mask, in the presence of a fluoride as an adhesion-reducing agent in order to produce a color-generating laminate incorporating an anodic film having detachable and non-detachable areas. The improvement of the invention involves forming the mask from a masking material which permits anodization of areas of the surface covered by the mask while preventing the adhesion-reducing agent from exerting a substantial adhesion-reducing effect in the areas of the surface covered by the mask. The anodic film having the detachable and non-detachable areas can then be formed by means of a single anodization step carried out in the presence of the adhesion-reducing agent. It is therefore unnecessary to employ two partial anodization steps as in the past, which simplifies the fabrication procedure and makes the procedure less expensive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.