Back to results
US 5,366,833 AGranted
Security documents
OwnerJoel F. Shaw, Gary A. Van Beekinventors
Life of this patent
Estimating the term…
Abstract
A method for making security documents using an electro photographic printer, particularly a photocopier or laser printer, includes the step of exposing the printed image to an accelerator, in liquid or vapour form. Under the influence of the accelerator, a second dye contained in the toner, used in producing the image, migrates into the document, thereby producing a second image in the paper in registration with the printed image. The process is applicable to images created on paper, security paper, and synthetic papers.
Claims14
A process for printing a security document which comprises:
- (i) creating an image pattern by means of an electro photographic printer;
- (ii) applying to the generated image, within the electro photographic printer, at least one particulate toner, which toner includes a first dye, and at least a minor proportion of a second dye;
- (iii) transferring and bonding the at least one particulate toner to the surface of the document to provide a document including an electro photographically printed image;
- and
- (iv) exposing at least a part of the electro photographically printed image on the document to an accelerator in liquid or vapour form to cause a major proportion of the second dye to migrate into the document, in registration with at least a part of the electro photographically printed image.
2 more elements
Dependencies are inferred from the claim text.