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.
An apparatus for security printing of a document on a substrate, having a first and second side, comprising: i) means for feeding variable data in a predetermined digital format to printing stations, ii) at least two printing stations, for image-wise depositing, in accordance to the predetermined format of the variable data, toner particles on the substrate, iii) means for fusing the toner particles to the substrate, to form a fused toner image, characterized in that a) the apparatus comprises means for introducing security features in the document and b) the means for fusing the toner particles to the substrate comprise means for heating and melting the toner particles such that between the melting toner particles and the substrate a contact angle of at most 90.degree. is formed and leave at most 25 mg/m.sup.2 of an external releasing agent on the fused toner image.
A label for a blood bag comprising a microporous plastic film including a matrix of interconnected pores for allowing gas to flow into and out of the blood bag through a labeled area. The pores allow ink to be absorbed at least on an outer surface of the label allowing the label to be printed and/or written on. The labels of the present invention have breathability with respect to gas that is similar to paper. However, the label is more durable than a paper label in that it can tolerate moisture, abrasion, temperature extremes, dimensional changes, and the like. Accordingly, the labels do not crack or wrinkle as easily as paper labels.
A toner for printing documents that are difficult to chemically or physically forge and that are readily easy to visually verify and methods of using and forming the toner are disclosed. The toner includes a colorant for printing an image on a surface of a document and a dye for forming a latent version of the image underneath a surface of a substrate. An image formed using the toner of the invention is readily verified by comparing the colorant-formed image and the dye-formed image. In addition, if a solvent is used in an attempt to alter the printed image on the substrate, the dye migrates or diffuses to indicate tampering with the document.
A system and a method for printing a secure document that is difficult to forge and readily easy to visually verify are disclosed. The system includes a colorant for printing an image on a surface of a document, a dye for forming a latent version of the image underneath the surface, a substrate, and a migration agent for facilitating the migration of the dye through at least a portion of the substrate. The migration agent may be coated onto a portion of the substrate or embedded within the substrate. An ink may serve as the migration agent, in which case, the ink contains a solute for the dye.
A toner for printing documents that are difficult to forge and that are readily easy to visually verify and methods of using and forming the toner are disclosed. The toner includes a colorant for printing an image on a surface of a document and a dye for forming a latent version of the image underneath a surface of a substrate. An image formed using the toner of the invention is readily verified by comparing the colorant-formed image and the dye-formed image.
