EP0055276A1

EP0055276A1 - A permanent record medium

Info

Publication number: EP0055276A1
Application number: EP81901805A
Authority: EP
Inventors: Robert Jack Avis
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-07-03
Filing date: 1981-07-03
Publication date: 1982-07-07
Also published as: WO1982000214A1; GB2079673A

Abstract

Le support comprend une pluralite de couches d'un materiau laminaire (15, 16, 17, 18, 19) comprenant deux couches exterieures (1, 16) en materiau impermeable, transparent, resistant au dechirement et au moins une couche interieure (19) prise en sandwich entre les deux couches exterieures, cette couche interieure etant faite en un materiau sur lequel des marques perceptibles optiquement apparaissent lorsque le support d'enregistrement est soumis a une pression localisee superieure a une certaine valeur de seuil. Cet effet peut etre obtenu en incluant dans la couche interieure (15) un materiau (14) comportant des encres microencapsulees qui filtrent le materiau lors de la rupture sous pression de la microencapsulation. Un procede de fabrication de cartes d'identites et d'autres documents semblables utilisant le support d'enregistrement permanent est aussi decrit.The support comprises a plurality of layers of laminar material (15, 16, 17, 18, 19) comprising two outer layers (1, 16) of waterproof, transparent, tear-resistant material and at least one inner layer (19) sandwiched between the two outer layers, this inner layer being made of a material on which optically perceptible marks appear when the recording medium is subjected to a localized pressure greater than a certain threshold value. This effect can be obtained by including in the inner layer (15) a material (14) comprising microencapsulated inks which filter the material during rupture under pressure of the microencapsulation. A method of making identity cards and other similar documents using the permanent recording medium is also described.

Description

A PERMANENT BECORD MEDIUM

Technical Field

The present invention relates to a permanent record medium on which can be formed optically distinguishable marks without requiring a separate marking instrument.

Background Art

Such permanent record media find applications in a wide range of fields; one important application is where security against removal of information is required. Examples of such applications include, for example, security cards, identity cards, record sheets and cards and other security-sensitive material where a degree of security against tampering with, particularly removal of, information marked on the cards or sheets is required.

In addition, wide use is now being made of plastics cards bearing not only optically distinguishable markings, but also magnetised elements for providing double security checks against unauthorised use. Such cards are embossed in order to make the visual markings permanent and to prevent any possibility of subsequent tampering. However such embossing can only be effected by relatively expensive machinery and there are many circumstances where investment in such machinery is prohibitive although some iorm of security system is desirable.

Disclosure of Invention

The present invention seeks to provide an alternative permanent record medium which can be used to provide, among other things, identity cards in an economical manner which permits widespread use where a certain degree of security is required but where the security risk is not extremely high. Examples of such use include, among other things, identity cards for supermarket staff, and passes to permit access to places where access is desired to be limited. Such limited access is required for example, at some libraries where certain collections of books cannot be made available to the general public. Likewise at art galleries, museums and other places, items of some value are to be made available to certain sections only of the public. Other uses may fall into the so-called "low security" class include certain legal documents, tax discs for cars and other display cards. The present invention seeks to provide a record medium in which the requirements of all these various potential users can be met. The medium of the present invention is also resistant to moisture and can therefore be used in circumstances where conventional record media such as paper or card would deteriorate rapidly or be unusable, and, moreover, the medium of the present invention does not require a marking instrument except a stylus for applying suitable pressure as will be described in greater detail below.

According to the invention a permanent record medium comprises a plurality of layers of laminar material including two outer layers of tear-resistant, transparent, impermeable materia.1 and at least one inner layer on at least a part of which appear optically distinguishable marks when the record medium is subjected to localised pressure, the marks appearing wherever the localised pressure exceeds a certain threshold value.

Preferably the tear-resistant, transparent, impermeable outer layers are sealed together at leasτ around the edges of the inner layer.

Because it is only necessary to apply localised pressure above a certain threshold value in order to form optically distinguishable marks on the record medium, and because the outer layers are sealed together to make an impermeable cell, the record medium can be used in hostile environments such as under water thereby enabling, for example, divers to make written, on the spot records without it being necessary to employ any more sophisticated recording techniques. Sketches or written reports of underwater activities or scenes can thus be made readily. The record medium is also usable out of doors where rain and inclement weather could cause deterioration of conventional record media such as paper or card marked with inks or pencil. Certain outdoor sports require permanent records to be made either during or immediately after the sporting activity, and the record medium of the present invention permits such records to be made at the time regardless of the weather, and has the additional advantage of being proof against subsequent alteration so that the sporting record constitutes a reliable record of the results.

In a preferred embodiment of the invention the inner layer includes, or lies adjacent to a layer including, a pressure-sensitive marking medium which forms optically distinguishable marks when subjected to localised pressure above the said threshold value. This pressure-sensitive marking medium may be one of several different types. For example, it may comprise or include a stratum of material incorporating a micro-encapsulated ink or variety of inks which react to form optically distinguishable marks when the encapsulation is ruptured by localised pressure of the said certain threshold value. Alternatively a composite layer incorporating waxed and carbon papers can be utilised. This latter visual marking arrangement is known as such, but has not before been incorporated in a closed cell to form a permanent record; indeed the structures previously used with. such, an arrangement have specifically incorporated means for separating the waxed and carbon papers to erase the visual indication at some stage after they have been formed. This, however, is contrary to the present inventive concept where reliable permanence is required, such permanence being obtained in this case by the security of lamination and sealing of the outer layers to the inner layers and to one another to prevent subsequent tampering, or to make any attempt at tampering to show up so distinctly that an adulterated record would not be accepted as valid.

The tear-resistant, transparent, impermeable outer layers are preferably laminated over the whole of the surface area of the inner layer and such laτninaτion is preferably effected by applying heat and pressure to a multi-layer assembly from which the record medium is to he made. Lamination is effected in the preferred embodiment by providing each transparent outer layer with a substratum of a heat-sensitive lamination welding material adhered thereto. One suitable material for this purpose, if each transparent outer layer is made of polyester film, is a substratum of polyethylene in a layer only a few microns thick. Under the action of heat and pressure the polyethylene melts and impregnates the inner layer or layers.

The inner layer or layers may comprise or include at least a part printed with permanent optically distinguishable marks in one or more colours. This may be information, identifying marks or logos or merely decorative or security background. The said part of the inner layer incorporating the pressure sensitive medium may cover an area less than the total area of the inner layer, or may extend over the whole of this area. The inner layer may comprise or include plastics material, cardboard or paper and likewise may comprise or include a magnetised area, layer or strip.

The present invention also provides an identity card made from a unit of permanent record medium formed according to the invention as defined above and provided with means for attachment of the card to the clothing of the wearer. Such attachment means may be formed as an attachment tag of the kind described and claimed in co-pending International Patent Application No . PCT/GB81/00113 or may comprise a cold deformable rivet for direct attachment of the card to a conventional clip as described in co-pending British Patent Application No. 8119835.

According to another aspect, the present invention provides a method of manufacturing a permanent record medium comprising the steps of forming a multiple layer assembly with a first layer of tear-resistant, impermeable, transparent plastics material, at least one inner layer or assembly of layers comprising or including a material or materials on which appear optically distinguishable marks when subjected to localised pressure above a certain threshold value, and a final layer of tear-resistant impermeable transparent plastics material, and sealing together at least the two outer layers at least around the edges of the inner layer. Preferably the outer layers are laminated under heat and pressure over the whole of the surface area thereof to one another and to the intervening inner layer. For this purpose it is preferable that the outer layers both have substrata of heat weldable laminating material such as polyethylene.

A preferred embodiment of the present invention will now be more particularly described by way of example, with reference to the accompanying drawings.

Brief Description of Drawings

Figure 1 is a partly exploded perspective view of an identity card formed as a permanent record medium in accordance with the present invention;

Figure 2 is a perspective view illustrating a portion of a record medium wallet assembly incorporating a photograph and an identity card formed from the permanent record medium of the present invention; and

Figure 3 is a side view, partly in section, of the assembly of Figure 2.

Best Mode for Carrying Out the Invention

Referring now to Figure 1 there is shown a multilayer assembly for forming an identity card which is resistant to forgery when completed. The assembly comprises a central layer 11 of paper or cardboard printed with a suitable identifying logo 12 and other printed information 13 and bearing on its upper surface a strip 14 of so-called carbonless marking paper. This comprises a paper having micro-encapsulated inks which react with one another to produce visual marks when ruptured by local pressure applied, for example, by a pointed instrument. The pressure required to rupture the encapsulation of the inks is rather high, but can be achieved by applying manually exercisable forces to a very small area such as one of the size of the point of a pencil or a ballpoint pen. A pointed metal or wooden instrument having no independent means for applying a mark can be used to make visual indications on such material likewise an ordinary manual or electric typewriter can be used. Materials of this nature are known as such and have been widely used as copy sheets for office machines.

On either side of the central layer 11 are two outer layers 15, 16 of transparent, tear-resistant polyester film in the region of 150 microns thick. Material of this thickness is suitable for the purpose of forming an identity card. Thicker or thinner material may be usable for other purposes. For example, for manufacturing larger sheets of record medium to receive, for example, permanent documents, a thinner material would be used.

Secured to the inner faces (that is the faces directed towards the central layer 11) of the two outer layers 15, 16 are respective layers 17, 13 of polyethylene adhered as substrata thereto. The length and width dimensions of the inner layer 11 are slightly smaller than those of the outer layers 15, 16 and 17, 18 which are identical to one another. The inner layer 11 also carries a strip 19 of magnetisable material along one edge. In order to complete the lamination the sandwich assembly described above is located in a laminating press with the required edge relationship, that is with the edges of the outer layers 15, 16 substantially coincident with one another and the inner layer 11 located centrally with its edges slightly inwardly located with respect to those of the outer layers. The press is then closed and heated, applying heat and pressure sufficient to cause melting of the substrata 17, 18 of polyethylene which then impregnates the material of the inner layer 11 causing bonding of the sandwich. The edge regions of the polyethylene substrata 17, 18 also bond to one another where they project beyond the area of the inner layer 11.

During this bonding operation the printing ink previously applied to the inner layer or card 11 is fused with the upper polyethylene substratum 17 andmigrates from the card 11, at least partly, into the polyethylene substratum 17. Subsequent attempts to separate the laminated structure in order to adulterate the card are thus inhibited by the fact that the bond between the polyester film 15 and the polyethylene 17 is stronger than that between the polyethylene substratum 17 and the card 11 so that subsequent separation takes place at the inner level lifting the marking ink, or at least a substantial proportion of the marking ink from the card 11 with the two outer layers 15, 17.

The initially blank strip 14 can receive validating marks or information such as a signature, or typed information, and like the printing ink on the card 11 the ink released by rupturing the micro-encapsulation of the strip 14 migrates at least partly into the polyethylene substratum 17 thereby further inhibiting the attempts at subsequent adulteration.

In use identity cards such as those shown in Figure 1 would generally be supplied by a manufacturer to a range of users with the strip portion 14 blank, individual logos and other information on the central card 11 being previously printed thereon as required by the user. In use, the blank strip portion 14 can be filled in with the validating information when the card is taken from a store thereof which should, preferably, be maintained under conditions of security suitable for the purpose in hand. Once validated the card cannot be altered by the removal of material and it is envisaged that by suitably selecting the inks or the manner of microencapsulation thereof a further security measure could be introduced by a process of deactivating the microencapsulation either by, for example, exposure to ultra-violet or other forms of radiation to reinforce the microencapsulation so that it is no longer rupturable or only rupturable at very much higher forces, such that manual pressure alonewill not cause rupturing, or alternatively to oxidise or .otherwise chemically affect the inks so that subsequent to the neutralising step rupturing of the micro-encapsulation will not lead to the formation of optically distinguishable marks. In this way increased security can be obtained since additional information cannot then be introduced on the card, nor can information already present be removed.

A major economy in the system of identity cards envisaged using the record medium of the present invention is that of using a relatively cheap heat laminating machine at a central station or factory to produce blank cards which can then be filled in or validated by the end user. The finished card is incorruptible and unique to the person or purpose for which it is finally completed, whilst the end user does not have to invest in specialised machinery for producing the cards. For users having a large number of branches, such as a supermarket chain, this represents a considerable economy since each branch would require to produce its own individual cards for its staff at regular intervals due to staff turnover, and this invention enables cards to be produced immediately so that no delay is experienced as would be the case if the cards had to be sent away to a central processing station for completion.

A similar identity card system can be used at military installations or other establishments requiring a high degree of security, since passes for visitors can be made out at a gate or other entrance and processed to make them incorruptible. Provided the store of blank cards is maintained under adequate conditions of security no possibility of forged cards exists.

A further adaptation of the present invention is envisaged to allow its use in association with a photograph identifying an individual. Since the card is prelaminated prior to its use a photograph cannot conveniently be incorporated unless the lamination is left incomplete (that is, covering only a part of the area of the card) and subsequent completion of the lamination effected after a photograph has been introduced between two outer layers. This, however, would involve the use of a heat lamination machine at the issuing station which loses the economic advantage mentioned above of not requiring such machines, although for certain purposes a cheap and simple machine could be provided for such small area of lamination.

However, to provide security for a photograph the wallet assembly illustrated in Figure 2 may be used. This comprises a base 21 of plastics material sufficiently thick to receive a plurality of recesses, such as those shown at 22, 23, 24, the depth of which corresponds to the thickness of a multiple laminated card such as that illustrated in Figure 1. Along one edge the base 21 is attached by a ligament hinge 25 to a transparent integrally moulded plastics cover 26 having, at its two free corners, respective female parts of two press studs 29, 30 the cooperating male parts of which are located on the free corners of the base 21 , and indicated with the reference numerals 27, 28. The cooperating parts of the press studs 27, 29 and 28, 30 are re-entrant such that once the press stud snap engagement has been made it cannot be released without breakage so that the cover can be closed only once. Further similar press studs may be provided along the edge of the base 21 and cover 26 for additional security if required in order to prevent any possibility of the identity card or photograph elements, which are fitted in respective recesses 22, 23 or 24, from being removed after closure of the cover 26.

As an alternative to press studs, solvent welding or adhesives may be applied to seal the edges of the cover 26 over the base 21 after insertion of the required elements into the recesses 22, 23,

As mentioned above record media formed in accordance with the present invention are strongly resistant against damp, insects, fungi etc. since the visible markings are entirely encapsulated within the sealed cell of material which is resistant to such agents. Further treatment of the cell to make it flame resistant may also be effected provided this does not interfere unduly with the transparency of the outer layers, although even if such interference is experienced this would still be tolerable providing it could be removed for reading and subsequently replaced for storage. For example, an outer layer of flame proof material may be provided, or a coating over the transparent cover could be applied, for example by spraying, as a final fire protection.

Claims

1. A permanent record medium comprising at least one marking layer (14) on which appear optically distinguishable marks when the record medium is subjected to localised pressure, the marks appearing wherever the localised pressure exceeds a certain threshold value,, characterised in that said marking layer (14) is provided on or forms at least part of an inner layer (11) of a plurality of layers of laminar material which also include two outer protective layers (15, 17; 16, 18) of tear-resistant, transparent, impermeable material disposed either side of said inner layer.

2. A permanent record medium as claimed in Claim 1, characterised in that the tear-resistant, transparent, impermeable outer layers (15, 17; 16, 18). are sealed together at least around the edges of the inner layer (11).

3. A permanent record medium, as claimed in Claim 1, in which the inner layer (11) includes or lies adjacent to the marking layer (14) which includes a pressure sensitive marking medium that forms the optically distinguishable marks when subjected to localised pressure above the said certain threshold value.

4. A permanent record medium as claimed in any of Claims 1 to 3, is. which the tear-resistant, transparent, impermeable outer layers (15, 17, 16, 18) are laminated over the whole of the surface area of the inner layer (11).

5. A permanent record medium as claimed in Claim 4, in which the lamination is effected by applying heat and pressure to a multi-layer assembly from which the record medium is made.

6. A permanent record medium as claimed in any of Claims 1 to 3, in which each transparent outer layer (15, 16) has a substratum of a heat sensitive lamination welding material (17, 18) adhered thereto.

7. A permanent record medium as claimed in Claim 5', in which each transparent outer layer is made of polyester film (15, 16) having a substratum (17, 18) of polyethylene adhered thereto.

8. A. permanent record medium as claimed in any of Claims 1 to 3 in which the inner layer (11) comprises or includes the marking layer (14) in the form of a stratum of material incorporating microencapsulated inks which react to form the optically distinguishable marks when the encapsulation is ruptured by localised pressure above the said certain threshold valve.

9. A permanent record medium as claimed in Claim 8, in which the said marking layer part (14) of the inner layer (11) covers an area less than the total area of the inner layer (11).

10. A permanent record medium as claimed in Claim 8, in which the inner layer (11) includes at least a part printed with permanent optically distinguishable marks (12, 13) in one or more colours.

11. A permanent record medium as claimed in any of Claims 1 to 3, in which the inner layer (11) is or includes plastics, cardboard or paper.

12. A permanent record medium as claimed in any of Claims 1 to 3 in which the inner layer (11) includes a magnetisable area, layer or strip (19).

13. An identity card made from or incorporating a permanent record medium as claimed in any preceding Claim.

14. An information sheet, questionnaire or like document made from or incorporating a permanent record medium as claimed in any of Claims 1 to 12.

15. A method of manufacturing a permanent record medium comprising the steps of forming a multiple layer assembly with a first outer layer (15, 17) of tear-resistant, impermeable, transparent plastics material, at least one inner layer or assembly of layers of material or materials (15, 14) on which appear optically distinguishable marks when subjected to localised pressure above a certain threshold value, and a final second outer layer (16, 18) of tear-resistant impermeable, transparent plastics material, and sealing together at least the two outer layers (15, 17; 16, 18) at least around the edges of the inner layer (15).

16. A method as claimed in Claim 15, in which the outer layers (15, 17; 16, 18) are laminated under heat and pressure over the whole of the surface thereof.

17. A method as claimed in Claim 15, in which the outer layers (15, 17; 16, 18) both have substrates (17, 18) of heat weldable laminating material such as polyethylene.

18. An identity card, information sheet, questionnaire or like document made from or incorporating a permanent record medium made by a method as claimed in any of Claims 15 to 17.

19. An assembly comprising an identity card as claimed in Claim 13, and a photograph; the identity card and photograph being housed in respective recesses in a casing and secured in a non-removable manner within the casing.

20. An assembly as claimed in Claim 19, in which the photograph and identity card are covered by a common layer of transparent plastics material.

21. An assembly comprising an identity card as claimed in Claim 18, and a photograph; the identity card and photograph being housed in respective recesses in a casing and secured in a non-removable manner within the casing.

22. An assembly as claimed in Claim 21, in which the photograph and identity card are covered by a common layer of transparent plastics material.