U.S. patent application number 09/725078 was filed with the patent office on 2001-05-31 for contactless or hybrid contact-contactless smart card designed to limit the risks of fraud.
Invention is credited to Kayanakis, Georges.
Application Number | 20010002035 09/725078 |
Document ID | / |
Family ID | 9552673 |
Filed Date | 2001-05-31 |
United States Patent
Application |
20010002035 |
Kind Code |
A1 |
Kayanakis, Georges |
May 31, 2001 |
Contactless or hybrid contact-contactless smart card designed to
limit the risks of fraud
Abstract
The invention relates to a contactless or hybrid
contact-contactless smart card, including an antenna on a support,
this antenna being formed by at least one turn of electrically
conductive ink which is screen printed on the support, two card
bodies 24 on each side of the support, each of the card bodies
consisting of at least one layer of plastic material, and a chip or
module 26 connected to the antenna. The support is made of paper
and features cutouts 22 in each corner at which the two card bodies
are welded together, thus giving its capacity to delaminate, when
the card is bent, at the location where the forces were generated,
which highlights any act of deliberate damage a posteriori as the
card retains the traces of the bending, and represents a
countermeasure against fraud.
Inventors: |
Kayanakis, Georges;
(Antibes, FR) |
Correspondence
Address: |
James C. Lydon
Suite 100
100 Daingerfield Road
Alexandria
VA
22314
US
|
Family ID: |
9552673 |
Appl. No.: |
09/725078 |
Filed: |
November 29, 2000 |
Current U.S.
Class: |
235/492 |
Current CPC
Class: |
G06K 19/07769 20130101;
H01L 2224/16 20130101; G06K 19/07749 20130101; G06K 19/07783
20130101; G06K 19/07372 20130101; G06K 19/073 20130101; G06K
19/07779 20130101; G06K 19/02 20130101 |
Class at
Publication: |
235/492 |
International
Class: |
G06K 019/06 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 29, 1999 |
FR |
99/15020 |
Claims
1. A contactless or hybrid-contact contactless smart card including
an antenna on a support, said antenna being comprised of at least
one turn of electrically conductive ink screen printed on said
support, two card bodies on each side of said support, each of said
card bodies being made up of at least one layer of plastic
material, and a chip or module connected to the antenna, said card
being characterized in that said support is made of paper and
features cutouts in each corner at which said card bodies are
welded together thereby enabling said support to delaminate when
bent at the location where the forces are generated by said
bending, which highlights any act of deliberate damage a posteriori
as the card retains the traces of the bending.
2. The smart card according to claim 1, in which said module is
inserted into a cavity milled in the card body opposite the side of
said support bearing the turns of the antenna.
3. The smart card according to claim 1, in which the chip is
positioned between said support and one of said card bodies.
4. A smart card according to one of the previous claims in which
each of said card bodies is comprised of at least two layers of
plastic.
5. The smart card according to claim 4, in which the two sheets
forming said card body layers have different stiffness and
thickness.
6. The identification smart card according to claim 5, in which the
sheet forming the external layer of the card bodies is made of a
stiff plastic material and the sheet forming the internal layer of
the card bodies is made of soft plastic having a low Vicat
temperature softening temperature.
7. The identification smart card according to claim 6, in which the
sheet forming the external layer is thicker than the sheet forming
the internal layer
8. A smart card in which each of the card bodies are comprised of
an additional sheet of plastic material, or layer or varnish,
acting as a cover.
9. A smart card according to one of the previous claims, in which
the plastic material forming the card bodies is polyvinyl chloride
(PVC), polyester (PET, PETG), polycarbonate (PC) or
acrylonitrile-butadiene-styr- ene (ABS).
10. A smart card according to one of the previous claims, in which
the ink of said screen printed turns is an electrically conductive
polymer ink loaded with conductive elements.
11. A smart card according to one of the previous claims, in which
at least one of the two card bodies is made up of transparent
sheets in order to have the paper support visible, and specifically
a graphic image printed on said support.
Description
TECHNICAL FIELD
[0001] The present invention relates to smart cards, and more
specifically a contactless or hybrid-contact contactless smart card
for which the antenna is on a support made of fibrous material such
as paper.
PRIOR ART
[0002] The contactless smart card is a system being used
increasingly in various sectors. In the transport sector, the card
has been developed as a means of payment. The same holds true for
the electronic wallet. Many companies have also developed
identification means for their personnel using contactless smart
cards.
[0003] The exchange of information between a contactless card and
the reader takes place via remote electromagnetic coupling between
an antenna embedded in the contactless card and a second antenna in
the reader. In order to create, store and process the information,
the card is equipped with a chip or an electronic module which is
connected to the antenna. The antenna and the chip are generally
located on a dielectric support made of plastic material (polyvinyl
chloride (PVC), polyester (PET), polycarbonate (PC) . . . ). The
antenna is obtained by chemical copper or aluminum etching on the
support or winding of conductive metal wire.
[0004] The card is often monobloc. The antenna support is often
inserted between two layers of plastic materials (PVC, PET, PC,
acrylonitrile-butadiene-styrene (ABS) . . . forming the upper and
lower card bodies and then heat bonded by hot lamination under
pressure. The chip or the module is connected to the antenna by an
electrically conductive glue or equivalent which enables the ohmic
contact to be established.
[0005] However, a card of this type has several major drawbacks.
The most significant drawback is that the plastic heat bonding
operation, implemented during the lamination process, leads to a
monobloc card having mediocre mechanical properties in terms of the
restitution of absorbed stresses. When excessive bending and
twisting stresses are encountered, all of the stress applied is
transmitted to the chip or electronic module and primarily to the
bonding points which make the connections. The mechanical strength
of the bonding joints is subjected to great strain which can cause
the module-antenna or chip-antenna connection to break. The antenna
may also be cut as a result of these mechanical stresses.
[0006] This specificity has been used by fraudulent individuals,
incited to commit fraudulent acts by the availability of "smart
card" technology to the general public.
[0007] Besides large-scale organized fraud which requires
significant means and highly-skilled technical specialists and
which consists in reproducing the behavior of a real card by using
another technical component, individual fraud is the most insidious
in that it involves individuals who are the customers of the card
issuing organization.
[0008] One can find occasional fraud, which consists in using the
card for a purpose other than the one it was designed for, or in
not respecting the usage conditions prescribed by the card's
issuer.
[0009] Indirect intentional fraud also exists in which a user,
unfamiliar with the technique, tries to obtain a service for which
a card is not programmed. This is the case of someone trying to
obtain money from an automated teller machine using a
transportation card, for example.
[0010] Finally, the last type of fraud is direct intentional fraud.
In this case, the user is thoroughly understands how the card works
and recognizes its weaknesses. It is thus relatively easy for this
type of individual to destroy the card as cleanly as possible, by
intense repetitive bending, when in possession of a card sold with
a credit (telephone cards, mass transit cards, highway toll
stations), and that this credit is exhausted or almost exhausted
without it being possible to prove the intent to fraud afterwards.
Then, the antenna may be cut, and the chip or module disconnected
without the card being marked. Owing to its intrinsic nature, the
plastic allows significant deformation without showing any visual
signs.
[0011] In these three types of fraud, individuals with the intent
to fraud make the card inoperative and then attempt to exchange or
reimburse the card with the card issuer. The latter are thus faced
with a serious problem as they want to treat their sincere
customers fairly but do not want to pay the costly price of falling
prey to fraud by blindly reimbursing faulty cards.
[0012] Another drawback of these cards is that they are comprised
of a composite stack of glued or heat bonded plastic materials with
different thermal expansion coefficients. As a result, systematic
unacceptable and irreversible distortion of the cards is observed
(twisting, warping), as well as a lack of mechanical resistance
when subjected to standardized or equivalent tests.
[0013] Furthermore, PVC exhibits poor thermomechanical properties.
During the card body lamination process, material flow is
significant and the antenna's shape factor is not maintained. This
leads to antenna malfunction as the electrical parameters
(inductance and resistance) vary. Even more serious, it is not
uncommon to experience antenna breakage in areas where strong sheer
stresses are present. This is particularly the case in angles and
at electrical bridging points.
[0014] The laminated ISO cards have a total thickness between 780
and 840 .mu.m. Considering the flow of material described above, it
is also very difficult to guarantee customers a narrow and
controlled distribution of the cards' population.
[0015] Another major defect of these cards is that after
lamination, the imprint from the copper etching is visible on the
printed card bodies. Although this does not prevent the card from
operating correctly, the defect is often emphasized by users who
are very concerned about the aesthetic criteria.
[0016] And finally, the cost of manufacturing cards with this
process is too high to enable any real increase in their usage.
DISCLOSURE OF THE INVENTION
[0017] The purpose of the invention is to mitigate these drawbacks
by supplying a contactless or hybrid contact-contactless smart card
enabling the risk of fraud to be limited by leaving a mark of any
attempt to damage the card, while resisting distortion and having
good mechanical resistance, thereby retaining its shape factor and
enabling the integrity of the electrical parameters to be
guaranteed.
[0018] The invention thus relates to a contactless or hybrid
contact-contactless smart card featuring an antenna on a support,
this antenna consisting of at least one turn of electrically
conductive ink screen printed on the support, two card bodies on
each side of the support, each card body consisting of at least one
layer of plastic material, and a chip or module connected to the
antenna. The support is made of paper and each corner features a
cutout enabling the two card bodies to be welded together, enabling
the bent card to delaminate at the location subjected to the
stresses generated by the bending which will highlight any act of
deliberate damage a posteriori.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The purposes, objects and characteristics of the invention
will become more apparent from the following description when taken
in conjunction with the accompanying drawings in which:
[0020] FIG. 1 represents the inverted drawing of the antenna on the
paper support of a hybrid contact-contactless smart card.
[0021] FIG. 2 represent the side of the support in contact with the
card body in which the cavity is milled to accommodate a module of
a hybrid-contact contactless smart card.
[0022] FIG. 3 represents a hybrid-contact contactless smart in its
final configuration.
[0023] FIG. 4 represents a cross section of the smart card,
represented in FIG. 3, along the axis A-A.
[0024] FIG. 5 represents a contactless smart card in its final
configuration.
[0025] FIG. 6 represents a cross section of the smart card,
represented in FIG. 5, along the axis A-A.
DETAILED DESCRIPTION OF THE INVENTION
[0026] In FIG. 1, the smart card according to the invention
consists of a paper support 10 on which an antenna is screen
printed. The antenna consists of two turns 12 et 14, screen printed
with an electrically conductive polymer ink, loaded with conductive
elements such as silver, copper or carbon. One end of each turn is
connected to one of the antenna contacts to the module which are
also screen printed, turn 12 being connected to contact 16 and turn
14 to contact 18. The turns are interconnected by an electric
bridge, most commonly referred to as the "cross-over" (not shown in
the figure). An insulating strip of dielectric ink 20 is screen
printed between the cross-over and turn 12. The antenna drawing is
reversed in relation to the normal drawing of an antenna for an ISO
format smart card. This special configuration provides a hybrid
contact-contactless smart card with a cavity for housing the
module, milled into the card body which is opposite the side of the
support bearing the screen printing, that is to say in the card
body which is in contact with the side of the support not bearing
the screen printing.
[0027] In this manner, when the support is reversed (contacts on
the left), as shown in FIG. 2, it can be noted that the contacts of
the module are in the standardized location for ISO format
cards.
[0028] In the case of a purely contactless card, as represented in
FIGS. 5 and 6, the drawing of the antenna is not reversed. As the
chip is positioned between the antenna support and one of the card
bodies, the card does not feature a milled cavity. The antenna thus
does not need to be protected. The structure of such a card is thus
more classic.
[0029] In FIG. 3, the hybrid contact-contactless smart card is
represented in its final configuration. As shown in FIGS. 2 and 3,
the support has a cutout in each corner. During the lamination
process, the card bodies 24 made of plastic material are heat
bonded together at the cutouts 22. As the paper pulp has low
internal cohesion, the core of the paper tends to delaminate when
it is subjected to shear stresses. This physical property was used
to create a card with a built-in and variable stress marker. By
blocking the corners by welding the two card bodies together, all
of the mechanical stresses are directed inside the card at the
location where the stress forces are exerted when the card is bent.
If these stresses are too strong, the paper delaminates and card
opens up and splits into two parts (the part which contains the
antenna connected to the module continues to function). Welding the
card bodies in the corners allows the card to remain useable. In
this manner, by acting on the type of paper and on its internal
cohesion, we can obtain a stress marker with variable
sensitivity.
[0030] The plastic material used for the card bodies is polyvinyl
chloride (PVC), polyester (PET, PETG), polycarbonate (PC) or
acrylonitrile-butadiene-styrene (ABS). The module 26 is installed
in the cavity and connected to the antenna. A cross sectional view
of the identification card along axis A-A, as shown in FIG. 4,
clearly depicts its configuration.
[0031] The paper support is sandwiched between the two card bodies.
Each card body consists of one sheet of plastic material.
Preferably, each card body is made up of two sheets, the sheet
forming the external layer and the sheet forming the internal
layer. According to a special embodiment, these layers may have
different stiffness. In this case, the external layer is made of
rigid PVC, while the inside layer is made of soft PVC with a lower
Vica softening temperature (the temperature at which the PVC shifts
from a rigid state to a rubbery state. The two layers may also be
of different thickness. The external layer is thus thicker than the
internal layer. The external layer has a thickness of approximately
310 microns (.mu.m) and the internal layer has a thickness of
approximately 80 .mu.m. The preferable plastic material is PVC. The
screen printed antenna is embedded in the internal layer of the
card body. Owing to the low stiffness of the PVC used, it becomes
fluid and traps the screen printed part in the mass of the card
during the card body laminating process. In this manner, the
antenna is much more resistant to mechanical stresses when using
identification card.
[0032] As shown on FIG. 4, the paper support 28 of the antenna is
inserted between two card bodies comprised, according to a
preferred embodiment, of three sheets. Each card body contains a
cover 30 which may be a sheet of transparent PVC film or varnish
layer, an external rigid PVC layer 32 and an internal soft PVC
layer 34. The cover 30 is approximately 40 .mu.m thick, the
external layer approximately 275 .mu.m thick and the internal layer
approximately 40 .mu.m thick. The thickness of these two layers may
vary depending on the final flexibility of the card. The module,
comprised of the double-sided circuit 36 and the chip 38 protected
by an overmolding resin, is inserted in the cavity designed to this
end. This cavity is obtained by milling the card body which is
opposite the side of the paper support on which the antenna is
printed. After the module is installed in this manner, it is
connected to the antenna contacts 40. One turn 42 of the antenna,
connected to one of the contacts, is trapped in the internal layer
34 of the card body made of soft PVC. The module is glued to the
card. Two different adhesives are used for this purpose. The first
glue is an electrically conductive adhesive 44 which enables the
module to be connected to the antenna contacts. This adhesive is
preferably an adhesive which contains silver. The second glue 46 is
used to secure the module to the card. Cyanoacrylate glue is used.
It is also possible to use a film-type "hot-melt" adhesive which is
placed under the module prior to its insertion in the card.
[0033] FIG. 5 represents the contactless smart card according to
the invention. The paper antenna support features cutouts 48 in the
corners. This support is sandwiched between the card bodies 50.
Unlike the hybrid contact-contactless card, neither of the two card
bodies has a cavity. This card does not have a module, but does
feature a chip 52 which is embedded in the card and thus not
visible on the card's surface. A cross sectional view of this card,
along axis B-B, is shown in FIG. 6.
[0034] In FIG. 6, the contactless card has the same structure as
the hybrid contact-contactless card. The paper support 54 is
sandwiched between two card bodies. According to a preferred
embodiment, each card body is made up of three sheets. Each card
body contains a cover 56 which may be a sheet of transparent PVC
film or varnish layer, an external rigid PVC layer 58 and an
internal soft PVC layer 60. The chip 62 is secured on the support
54 and is connected directly to the antenna contacts 64 with
electrically conductive glue enabling ohmic contacts to be
established. One turn 68 of the antenna, connected to one of the
contacts, is trapped in the internal layer 60 of the card body made
of soft PVC. The chip is thus trapped between the paper support and
one of the two card bodies. The purely contactless card thus has
both the same structure and properties as the hybrid
contact-contactless card.
[0035] According to another special embodiment, at least one of the
two card bodies consists of transparent sheets in order to render
the paper support visible and particularly a graphic image printed
on the support. Graphic printing techniques are well-known and
perfectly controlled. The resulting quality is remarkable in terms
of resolution and rendition of color compared to that obtained on a
PVC type plastic support. This unique property of the paper may be
used to manufacture cards on which one of the sides of the support
may be dedicated to a high-quality graphic print. It thus becomes
easy to put advertising, the brand name of company that distributes
the card or even identification photos on the card, in the case of
personal smart cards.
[0036] The smart card with a paper support according to the
invention behaves differently than a monobloc PVC card. Paper is a
fibrous material which absorbs part of the energy stored when the
card is subjected to mechanical stresses. This cushioning effect
softens the natural spring effect of the card bodies. During smart
card bending and twisting tests, the energy is thus directed to the
center of the paper support and not on the module or chip-antenna
contacts, as on monobloc PVC cards. The module or chip connection
and antenna integrity are thus preserved.
[0037] In this manner, the card according to the invention has two
major qualities for the companies which use it: the preservation of
the electrical components provide this card with enhanced solidity
and, in case of card malfunction, the delamination property of the
paper allows to make sure that the card has not been subjected to
intensive folding for the purpose of frauding. When a card user
intentionally or unintentionally bends the card in an excessive
manner, the paper support delaminates. Unlike PVC cards, the twist
or bend mark appears on the card. In the case of extreme bending or
twisting, a crack appears in the card body. The card remains
functional despite this twisting or bending. This situation thus
discourages the individual from continuing his/her attempts to
render the card inoperable for the purpose of claiming
reimbursement or exchange of the card with the issuing
organization, owing to the visible marks left on the card.
[0038] Furthermore, the visco-elastic properties of the polymer ink
used in the screen printing process enable the turns to better
resist mechanical stresses encountered during the lamination phase.
Antenna breakage in areas subjected to strong sheer stresses are
thus avoided.
[0039] Finally, the imprint from the screen printed turns is
practically invisible on the card bodies. This parameter, which is
not involved in the operation of the card, is very important for
the distributors and the users who are very concerned about the
aesthetic criteria.
* * * * *