GB2280639A

GB2280639A - An applied film to prevent copying of a document.

Info

Publication number: GB2280639A
Application number: GB9412157A
Authority: GB
Inventors: Helmut Steininger; Peter Heilmann; Norbert Mueller; Peter Hewkin
Original assignee: BASF Magnetics GmbH
Current assignee: Emtec Magnetics GmbH
Priority date: 1993-06-18
Filing date: 1994-06-17
Publication date: 1995-02-08
Anticipated expiration: 2014-06-17
Also published as: GB2280639B; DE9409532U1; JPH07166138A; FR2706640A3; FR2706640B3; DE4320219A1; GB9412157D0

Description

- 1 Antico.pv Film 2280639 This invention relates to an anticopy film for

covering documents, of the kind comprising a film of transparent material corresponding to the size of the document to be covered or to parts thereof, having regularly recurring sections which are opaque or reflective in the thickness of the film material or parts thereof and, due to their corresponding geometrical arrangement, make the film appear opaque for a defined viewing-angle range on the film and transparent in viewing-angle ranges differing therefrom, the anticopy film being provided with a transparent adhesive for adhering to the document to be covered.

German Patent Application P 42 26 906 describes an anticopy film of the kind referred to. The film, which is intended to render documents uncopyable by a photocopy machine, essentially comprises a transparent plastics film with opaque areas in the film or on the film surface, in a multiplicity of various arrangements through which the film appears opaque in the direction of exposure of a copier and appears transparent when viewed from another viewing-angle range. The anticopy film can be attached to the document by means of suitable commercial adhesives.

It is an object of the present invention to provide an anticopy film whose transparent material containing the opaque or reflective sections and the adhesive are environmentally acceptable.

We have found that this object is achieved by an anticopy film of the kind referred to whose transparent material containing the opaque or reflective sections and the transparent adhesive are halogen-free.

The transparent material of the anticopy film is thus biodegradable and can, for example, be composted together with paper. Moveover, the material can, after appropriate precomminution, easily be recycled together with paper, since it contains no foreign materials which impair the quality of the paper.

In particular, the environmentally compatible material can comprise polycaprolactam (polyamide), cellulose acetate, polymeric starch derivatives or homopolymers or 5 copolymers of linear polyesters of 3hydroxybutanoic acid or 3-hydroxyvaleric acid. Furthermore, the material may have been mixed with bioactive plasticizers or other additives.

The transparent adhesive, which should remain adhering to the document material and not be removable, should, according to the invention, likewise comprise halogen-free material. A corresponding solvent or dispersion adhesive is therefore used.

The following adhesives are advantageously suitable:

Acrylate, in particular phenyl acrylate, or styrene- butadiene or in the form of a heat-sealable film, for example a polyethylene film. The adhesive can be covered by a release film or a siliconized paper.

If a f ilm is used, it should advantageously also comprise a halogen-free material.

The transparent material employed is furthermore particularly environmentally acceptable since itcan be disposed of without risk by simple landfilling or by incineration, during which no pollutants are liberated since all the materials used are halogen-free.

Embodiments of the invention will now be described, by way of example only, with particular reference to the accompanying drawings, in which:

Figure 1 is a schematic view of an anticopy film with a base and an adhesive coating on a document, Figure 2 is a schematic view of an anticopy film as - 3 in Figure 1 not on a document but with a cover film over the adhesive coating, and Figure 3 is a schematic view of an anticopy film not on a document and without a base but with an adhesive coating and a cover film.

The anticopy film is shown in cross-section in the drawings and comprises a film 3 of transparent material which corresponds to the size of the document 2 to be covered or to parts thereof, having regularly recurring sections 5 which are opaque or reflective in the thickness of the film material or a part thereof. These sections can also have been applied by printing. The mutually offset arrangement of the sections means that the film, in a similar manner to an adjustable venetian blind, appears opaque in plan view, corresponding to the copying direction 6, and transparent in a somewhat more inclined viewing direction 7. Various embodiments of this construction of the film are shown and explained in the German patent application referred to in the introduction of this specification.

The anticopy film 3 can also be arranged on a transparent base film 1 (Figure 2) or not (Figure 3).

For reliable application of the anticopy film to the document to be covered, the film is provided with an adhesive coating 4, which can be covered by a release film 8, which should be peeled off before the film is used (Figure 3).

The base film 1 and the release film 8 should likewise be made of halogenfree materials if possible.

In the embodiment without a protective film, the anticopy film is provided, for example, with a blocking-free heat-sealing adhesive. For use, the anticopy film from the roll, from a block of sheets or as a single sheet and is - 4 laminated onto the document to be protected using pressure and heat.

If the anticopy f ilm is coated with a permanently moist contact adhesive, a protective film, for example in the form of a silicone-coated paper or a correspondingly treated film, must be used for non-stick separation of individual anticopy film layers. The protective film is peeled off before the anticopy film is used. In this embodiment, the anticopy film can be cold-laminated with exclusive use of pressure.

In accordance with the required environmental acceptability of the anticopy film, the transparent material containing the opaque or reflective sections 5 of the film 3 is halogen-free. Examples of suitable film materials are:

- polycaprolactams, cellulose acetate, polymeric starch derivatives, homopolymers and copolymers of linear polyesters of 3hydroxybutanoic and 3-hydroxyvaleric acid.

It may be expedient to mix the materials with bioactive plasticizers and additives which promote biodegradation of the materials.

The invention relates to an anticopy film for covering documents which, for protection against copying, appears opaque in the essentially vertical plan view and transparent in an inclined viewing direction. where the film adheres to the document by means of an adhesive coating, and the film material and the adhesive coating are halogen-free.

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Claims

- 5 CLAIMS

An anticopy film for covering documents, comprising a film of transparent material corresponding to the size of the document to be covered or to parts thereof, having regularly recurring sections which are opaque or reflective in the thickness of the film material or parts thereof and, due to their corresponding geometrical arrangement, make the film appear opaque for a defined viewing-angle range on the film and transparent in viewing- angle ranges differing therefrom, the anticopy film being provided with a transparent adhesive for adhering to the document to be covered, wherein the transparent material containing the opaque or reflective sections of the film and the transparent adhesive are halogen-free.
2. An anticopy film according to claim 1, wherein the transparent material comprises polycaprolactam.
3. An anticopy film according to claim 1, wherein the transparent material comprises cellulose acetate.
4. An anticopy film according to claim 1. wherein the transparent material comprises polymeric starch derivatives.
5.

An anticopy film according to claim 1, wherein the transparent material comprises homopolymers or copolymers of linear polyesters of 3hydroxybutanoic or 3- hydroxyvaleric acid.
6. An anticopy f ilm according to any of claims 1 to 5, wherein the transparent material has been mixed with bioactive plasticizers and other additives.
7. An anticopy f ilm according to any of claims 1 to 6, wherein the transparent adhesive remains adhering to the document material and cannot be removed.
8. An anticopy film according to claim 7, wherein the adhesive is a solvent or dispersion adhesive.
g. An anticopy film according to claim 7, wherein the adhesive is an acrylate, e.g. phenyl acrylate, adhesive.
10. An anticopy film according to claim 7, wherein the adhesive is based on styrene-butadiene.
11. An anticopy film according to claim 7, wherein the adhesive is formed by a heat-sealable film, e.g. a polyethylene film.
12. An anticopy f ilm according to any of claims 7 to 11, wherein the adhesive is covered by a release film or a release sheet, e.g. siliconized paper.
13. An anticopy film constructed and arranged substantially as herein described with reference to, and as illustrated in, Figures 1, 2 or 3 of the accompanying drawings.