WO1996036009A1

WO1996036009A1 - Improvements in smart cards

Info

Publication number: WO1996036009A1
Application number: PCT/GB1996/001105
Authority: WO
Inventors: David Barrington Everett; Bill Reding
Original assignee: Mondex International Limited
Priority date: 1995-05-11
Filing date: 1996-05-09
Publication date: 1996-11-14
Also published as: AU5655596A; GB9509583D0; ZA963654B

Abstract

A smart card (1) is manufactured by initially manufacturing a larger card, preferably of some standard size such as ISO ID-1, and overlaying one surface of the card with a film material. The required (smaller) card (3), and including the computing circuitry, is then cut out of the larger card leaving a continuous gap (4), the smaller card being maintained in place by the film. In this way, the manufacturing and transportation processes already set up for the larger cards can be used without significant modification for the smaller cards. The smaller card (3) can be separated off by unpeeling the film, the remaining part of the larger card being discarded or recycled.

Description

"IMPROVEMENTS IN SMART CARDS"

This invention relates to smart cards.

Smart cards are small plastics cards similar to the well-known credit and debit cards but which contain some computing capacity in the form of an IC (integrated circuit) microprocessor and associated circuitry and components. The associated components vary with the use to which the card is to be put, but typically (but not necessarily) include a contact pad containing a plurality of contacts for connection to external circuitry. Smart cards have a variety of uses, for example in door access control and in financial transactions of various types, for example, as carriers of "electronic cash", for which purpose the microprocessor includes a memory which stores, amongst other things, an accumulated value in multiple currencies. For convenience in being able to use smart cards across a wide variety of commercial readers and in different countries a number of internationally-recognised standards have been adopted to ensure that cards are the same size, and that externally-contactable or readable components such as electrical contacts are physically and electrically compatible with one another. One such standard is the ISO standard in which the standard credit card of the type used by individuals is of specification ISO ID-1. However, a smaller size of smart card, CEN ID- 000, is also commonly in use, mainly for controlling machinery and similar. These cards are of much smaller physical size, but still can contain the same computing circuitry as their larger counterparts.

For convenience in manufacture, it has become customary for these smaller cards to be initially manufactured as part of a larger card, of the larger and more common ISO ID-1 size. This is because the machinery which manufactures the cards is set up for the larger cards, and they are easier to handle, being physically larger. The larger card may or may not be equipped with a magnetic stripe.

Figure 1 of the accompanying drawings shows a conventional smart card 1 made out of plastics material. The external dimensions of the card correspond to the ISO ID-1 size - i.e. the same as a conventional credit card. The card is equipped on its upper surface with a contact pad 2 containing a plurality of separate contacts for connection to external readers (not shown) and similar apparatus. The layout and number of these contacts is laid down in ISO standards, but is not important to the present invention and is shown diagrammatically. The IC microprocessor and associated circuitry (not shown) is normally positioned behind the contact pad 2 and is contained wholly within the thickness of the card (typically about 0.75 mm).

It will be seen that part 3 of the card is separated from the remainder by a through-slot 4 extending around the perimeter of part 3. Narrow bridges 5 cross the slot 4 to hold the part 3 in position, but enable it to be broken away. The part 3 contains all of the computer circuitry which is contained in practice in quite a small area underneath and immediately adjacent the contact pad 2. Therefore the part 3 can be broken away to form a separate, and physically smaller, smart card possessing all of the computing power of the larger card.

As shown, the smaller smart card is of the aforementioned CEN ID-000 size but, of course, other sizes are possible.

This method of manufacturing a smaller card by initially manufacturing a larger card and allowing someone - usually the end user - to complete the final manufacturing process by breaking away the smaller card as described above, has proved very convenient, both in the manufacture itself, and in the processing of the card after manufacture. However, a problem arises because the current method of removing the smaller card from the larger involves the user pressing out the smaller card to break the bridges 5 formed across the slot 4. Unless this operation is carried out carefully, excessive strain can be placed on the smaller card, and in particular damage can be caused to the electronic circuitry which is fragile and prone to cracking and breaking. In addition, broken-off remnants of the bridges 5 can remain to spoil the otherwise smooth outside edge of the card and can potentially interfere with machinery.

The present invention seeks to overcome these problems by providing firstly that the slot 4 is continuous - i.e. there are no bridges 5 to break - and secondly that a film of material is applied to one surface of the card during manufacture, which sheet is operable to maintain the part 3 of the card in position until such time as the user removes the part 3 by peeling off the film to separate part 3 from the remainder of the card.

The film is advantageously made of plastics material and may be of the type of plastics material which will self-stick to the surface of the card, or may have an adhesive backing with which it is used to stick to the surface of the card. In any event, it is desirable that the outwardly facing surface of the film is reasonably smooth so as not to present a high friction surface when the card is passing through machinery during the manufacturing and setting-up stages. In an embodiment, the coefficient of friction of the outwardly facing surface of the film is approximately the same as that of the material from which the card is made.

In addition the film should be thin enough not to increase the total thickness of the card to an extend where it will not pass through the machinery intended for it. For example, with a card of nominal thickness 0.75 mm, with a tolerance maximum of +0.08 mm, a tape of maximum thickness 0.11 mm would give an absolute maximum possible thickness overall of 0.94 mm. Such a figure is on the verges of acceptability for some machinery which the card has to pass through before it reaches the end user (who, of course, removes the film).

The film need not cover the whole surface of the card, but it should at least cover a portion of the part of the card which is to be separated. In the preferred embodiment, the sheet covers the whole of that part of the card which is to be separated.

In its broadest aspects, the invention comprises a smart card and a method of making a smart card. The smart card of the invention comprises a sheet of plastics material, said sheet housing within its thickness computer circuitry for carrying out certain functions of the card, a through slot formed in said sheet, said through slot being such as to divide said sheet into two separate parts, said computer circuitry being positioned in one of said parts, and a film of material adhered to at least one surface of said sheet over at least part of the area of both of said parts, said film being operable to keep the two separate parts in a substantially fixed positional relationship with respect to one another so that the card as a whole can be handled as a single unit.

The method of making a smart card according to this invention comprises the steps of initially making a card which is formed of a sheet of material which is physically larger than the size required, adhering to at least one surface of said sheet a film of material, thence cutting said sheet into two separate parts, one of which parts contains computer circuitry for carrying out certain functions of the card, said film being arranged to overlay at least sufficient of each of the two parts to keep them in a substantially fixed positional relationship to one another so that the card as a whole can be handled as a single unit.

The cutting of the sheet may advantageously be carried out by a milling or equivalent cutter which is applied to the opposite surface of the sheet to that which the film is adhered to. By accurate adjustment of the depth of cut, the sheet can be cut right through without affecting the integrity of the film.

The final step in the manufacturing process, generally (but not necessarily) performed by the end user, is to peel away the film so that the two parts of the card become separated. The part not containing the computer circuitry can then be discarded.

In order that the invention may be better understood, an embodiment thereof will now be described by way of example only and with reference to the accompanying drawings in which:- Figure 1 is a top plan view of a known smart card;

Figures 2 and 3 are top and underside plan views respectively of a smart card manufactured in accordance with the present invention.

Referring to Figures 2 and 3, the card is similar to that shown and described with reference to Figure 1 and identical reference numerals are used where appropriate. The main difference to be seen in Figure 2 is that the slot 4 which separates the part 3 of the card from the remainder forms a continuous loop - in other words, the bridges 5 are not present. In order to maintain the positional relationship between the part 3 and the remainder of the card, a film 6 of plastics material having upper and lower edges 8 and 9 respectively is adhered to one surface of the card - in this case the underside of the card, as shown in Figure 3. The film 6 could be made from material other than plastics material, such as paper, but plastic is the currently preferred material. The plastic film may be made of a material which has a natural tendency to cling or adhere; alternatively it can be provided with an adhesive layer for the purpose of adhering to the card. The film can be provided over both surfaces of the card, but it is found that coverage of just one surface is sufficient. As shown in Figure 3, the film 6 overlies part of the undersurface of the card, including part of the (optional) magnetic stripe, illustrated diagrammatically under reference 7, and further including the whole area of part 3. Although the whole of part 3 is covered in this embodiment, this is not essential; it is, however, necessary that sufficient of the area of part 3 is covered to ensure that part 3 is held stably in position throughout all the anticipated handling of the card. In order to remove the part 3 from the remainder of the card the film 6 is simply peeled back to allow the part 3 to be removed without any strain being applied to it. Once the part 3 is removed, the remainder of the card 1 may be discarded. To manufacture the smaller card, the larger card is first produced in the normal manner and then the film 6 applied to one face. A milling cutter is now used to mill the slot 4 from the opposite face. It has been found that it is possible to locate the depth of cut sufficiently accurately that the cutter cuts right through the card, but leaves the film 6 substantially undamaged.

Although this basic concept can be used for cards of any size, the main purpose envisaged is to make CEN ID-000 sized cards, using the ubiquitous ISO ID-1 cards as a "carrier" during manufacture and, optionally, transport to the end user. In this case, the card 1 shown in Figures 2 and 3 is of ISO ID-1 size, and the part 3 of the card 1 is of CEN ID-000 size. Thus manufacture and transportation processes already set up for the ISO ID-1 cards can be used without modification for the smaller CEN ID-000 cards.

Claims

1. A smart card comprising a sheet of plastics material, said sheet housing within its thickness computer circuitry for carrying out certain functions of the card, a through slot formed in said sheet, said through slot being such as to divide said sheet into two separate parts, said computer circuitry being positioned in one of said parts, and a film of material adhered to at least one surface of said sheet over at least part of the area of both of said parts, said film being operable to keep the two separate parts in a substantially fixed positional relationship with respect to one another so that the card as a whole can be handled as a single unit.

2. A smart card as claimed in claim 1 wherein said first of said parts of said card is larger than the second of said parts of said card and completely surrounds the second part in the manner of a border.

3. A smart card as claimed in claim 2 wherein said film extends across said second part from one side to the other in such a way as to maintain the second part coplanar with the first part.

4. A smart card as claimed in either one of claims 2 or 3 wherein said computing means is carried wholly by said second part of the card.

5. A smart card as claimed in any one of the preceding claims wherein a continuous gap separates said parts from each other.

6. A smart card as claimed in any one of the preceding claims wherein the coefficient of friction of the outwardly facing surface of the film is approximately the same as that of the plastics material from which the card is made.

7. A method of making a smart card comprising the steps of initially making a card which is formed of a sheet of material which is physically larger than the size required, adhering to at least one surface of said sheet a film of material, thence cutting said sheet into two separate parts, one of which parts contains computer circuitry for carrying out certain functions of the card, said film being arranged to overlay at least sufficient of each of the two parts to keep them in a substantially fixed positional relationship to one another so that the card as a whole can be handled as a single unit.

8. A method as claimed in claim 6 wherein the cutting of the sheet is carried out by a cutter applied to the opposite surface of the sheet to that which the film is applied to.

9. A method as claimed in either one of claims 6 or 7 wherein the two parts of said sheet are separated by peeling away the film so that said one part becomes the smart card, and the other of said parts is discarded.