Printing – Embossing or penetrating – Processes
Patent
1997-05-06
1999-02-23
Burr, Edgar
Printing
Embossing or penetrating
Processes
283 72, 283901, B31F 107
Patent
active
058733051
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a method for protecting from forgery, assuring the authenticity of or personalizing pre-printed sheets (both of small size such as documents, etc. and of large size such as continuous paper or strips wound in reels) and in particular pre-printed by laser or ink-jet printers, plotters, airbrushes, and xerographic, typographic, lithographic, off-set, serigraphic, flexographic, copper-plate, rotogravure machines with any kind of drying, including UV and electron-beam reticulation.
BACKGROUND OF THE INVENTION
Various methods are used in order to protect from forgery or to assure the authenticity of printed documents.
The use of watermarked paper and the impressing of holograms are among those methods which offer a greater guarantee. These are two fairly expensive methods either, in the case of watermarked paper, for the costs involved in the paper manufacturing process, or, in the second case, for the costs of preparation of the type plate (electrotype) and even more of the paper substrate in that said substrate is usually previously coated with a film of a material (such as PVC, polyester, polypropylene, polythene, coating, etc.) suitable to receive and permanently retain the holographic microengravings engraved by the electrotype. Moreover, in the case of holograms the manufacturing costs are economically sustainable only for mass productions (generally using substrate material in reels) whose plant require high investments.
For example, WO-A-89/03760 discloses a method for impressing holograms on a paper or plastic sheeting by providing a coating thereon and then embossing the coated substrate. The coating can be applied in different ways according to the thermoplastic material employed in the process (e.g. polyethylene by extrusion). Regardless of the specific process, this coating step of covering the whole surface of the sheet with a uniform coating layer implies the above-mentioned problems.
SUMMARY OF THE INVENTION
The present invention is aimed at overcoming these drawbacks and limitations by providing a method for protecting from forgery, assuring the authenticity of or personalizing pre-printed sheets, which has a significantly low cost and is suitable not only for mass production applications but also and particularly for small productions.
To this purpose, the method according to the invention provides the protection or personalization of the pre-printed sheet by impressing microengravings, on all or some of the printed portions of the sheet, said microengravings corresponding to holograms or diffraction patterns or images or words and being obtained through a hot embossing process, carried out at a temperature higher than the softening point of the dyeing substances used for obtaining the print on the pre-printed sheet.
The features of the invention will be apparent from the following description of a non-limiting embodiment schematically illustrated in FIG. 1.
According to the method of this example, once the type and content of the microengraving to be transferred on the pre-printed sheets have been selected (e.g. the microengraving of an hologram showing a specific figure or producing a particular visual effect), a type plate of the hologram is prepared according to the processes conventionally used for the embossing of holograms, said plate usually consisting of a flexible metallic sheet having the microengraving of the hologram and designed to be applied onto that of the two cylinders of an embossing group which is usually called "embossing cylinder".
Assuming that the treatment is to be applied to pre-printed sheets of small size and not in reels (this latter case being particularly simple as it will be said further on), the sheets have to be subjected to an embossing process by using said plate.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 illustrates in a highly schematic way the members of a machine which can be used to said purpose. The meaning of the various elements therein is the following. when it is desired to feed the ma
REFERENCES:
patent: 4135962 (1979-01-01), Sinclair et al.
patent: 4152389 (1979-05-01), Miller
patent: 4701235 (1987-10-01), Mitsam
patent: 4725111 (1988-02-01), Weitzen et al.
patent: 5142383 (1992-08-01), Mallik
patent: 5208089 (1993-05-01), Stover
Burr Edgar
Ghatt Dave A
Oranmay Investments B. V.
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