Process for producing electronic cards

0001The invention relates to a manufacturing process of electronic charts and maps obtained by such a method.

0002The map word must be considered in the present invention, in a broad sense, including in particular all portable object with standard dimensions, and having, firstly, a micromodule and, hand, a body serving as portable media. However, the invention aims in particular smart cards and, among these cards, cards with a functioning without contact, in which the micromodule is connected to an antenna for electromagnetic transmission Datas. In the following discussion, the term contactless card, a card having an operating exclusively contactless or so, a hybrid card having a contact-free operation classic operation, contact.

0003The manufacture of large electronic boards series can be carried out according to various methods.

0004Some methods involve an injection, a temperature above 90 ° C and under high pressure, for example of the order of 700 kg / cm², A viscous thermoplastic polymerized state melted in a closed mold cavity. After cooling below its melting point, this material forms a thickness of the card body.

0005However, such methods do not offer the possibility of a simple adjustment of the viscosity of the injected plastic. However, when designing a method of making cards by injection, is necessary to perform many tests varying in particular the viscosity of the injected material, to arrive ultimately at an optimal process, acceptable industrially, with zero defects.

0006EP-A-0570784 discloses a process for the manufacture of a smart card type without contact, that is spread on a work plan binder in liquid form and preferably with sufficient viscosity to not spread so too large. An electronic module is embedded in the layer formed by said binder.

0007The present invention aims to propose a process electronic card manufacturing mass, which overcomes the cost aforementioned drawbacks, and which, inter alia a simply adjusting the viscosity of the plastic injected or delivered.

0008Another object of the invention is to enable obtaining card thickness whose characteristics, such as adhesion, stiffness or the temperature resistance are adjustable and controllable with ease.

0009These goals, as well as others that will appear hereinafter, are achieved by a method wherein for the manufacture of the card, is spread a mixture comprising a low liquid monomer viscosity. The addition of a third substance will then adjust the viscosity of the mixture comprising said monomer.

0010The invention therefore relates to a method of manufacturing an electronic card as defined in claim 1.

0011The description which follows, and which has not limiting, will better understand how the invention can be in practice.

0012It should be read with reference to the accompanying drawings, wherein :<ul><li>Figure 1A shows, in cross-section, contact card obtained by a process according the invention;</li><li>FIG 1B shows, in cross section, a contactless card obtained by a process according the invention;</li><li>2 illustrates the reaction scheme set used in a method according to the invention; and</li><li>3 illustrates schematically a mode Implementation of the method of the invention.</li></ul>

0013In the example of this description, electronic cards 1 correspond to ISO 7810. They include a micromodule 2 and a body Map 3.

0014The card body is a parallelepiped 3 rectangle thin with dimensions out all are of the order of 85 mm length, 54 mm width, and 0.76 mm thick. It has n layers. The number n may be equal to one. However, in the general case, it is greater than one. In the example of Figures 1A and 1B, it is equal to three, and the card body 3 then comprises a layer of above 4, an underlayer 5, and a sub-layer 6.

0015The micromodule 2 is inserted into the card body 3. It is in contact with a plastic layer polymerized the card body 3, for example the underlayer 6. It includes an integrated circuit chip and 7 connection terminals 8.

0016In the case of a contact card (Figure 1A), the connection terminals 8 are connected to pads 9 metallized contact flush with the surface of card body 3 and forming metallizations 10.

0017In the case of a contactless card (Figure 1B), the connection terminals 8 are connected to beaches contact 11 of an antenna 12 included in the body of card 3. The antenna 12 is formed either of a coil wire whose diameter is of the order of 30 .mu.m, or of a metallized or laminated dielectric with the metal of a thickness of the order of 80 microns, or, in the case of a microwave antenna, a dielectric sheet whose thickness is close to 80 .mu.m.

0018According to the invention, for the manufacture of a polymerised plastic layer 6 of the card body 3, spread on a production card support 1 a mixture comprising at least one monomer referenced 100 in Figure 2. This monomer 100 is liquid and low viscosity. In practice, the viscosity of or 100 monomers is between 100 and 1000 mPa.s approximately and preferably less than 500 mPa.s about a TREP temperature. spreading of the mixed.

0019On the other hand, is initiated or initializes the polymerization of the monomer through a 100 initiator 101. The initiator 101 may be a catalyst ion or radical, or else radiation actinic.

0020In the case where the initiator 101 is a catalyst, it is present in the mixture, during the spreading, and decomposes during the initiation of the polymerizing, in one or more products of 102 decomposition of said seed.

0021Against by, in the case where the initiator 101 is a actinic radiation such as, for example, a UV radiation, said initiator 101 is, of course, not present in the mixture but it induces the a decomposition agent thereof which forms a radical or ion polymerization initiating. To the Following the priming include one or more Decomposition products 102 said boot.

0022When the polymerization of the monomer 100 is sends only in the presence of an initiator 101, the polymerization time is significant, more than 15 minutes. Also, the reaction is accelerated polymerization by adding, in the mixture comprising the initiator 101 and the monomer 100, an accelerator 103 which can not, in itself, initiate the reaction polymerization.

0023According to the invention, adjusting the amount accelerator 103 so as to adjust, especially, the rate of polymerization of monomer 100. Accelerator 103 is present in large quantities in mixing and active, more polymerization is fast, and the process is industrially profitable.

0024However, a compromise must be found relatively to accelerate the polymerization. In Indeed, a too rapid polymerization CAUSES rise too high temperature due to the exothermicity of the polymerization reaction. In practice, presence of an accelerator 103 in sufficient quantity, the temperature of a mixture comprising only the initiator 101 and the monomer 100 rapidly increases until the order values ​​of 80 ° C. Such an temperature induced, in particular, training bubbles whose elimination is necessary tricky. She can further damage the micromodule or of the chip of the card. It promotes finally the withdrawal.

0025Moreover, in the presence of an accelerator 103 only, the polymerization of the monomer leads 100 a brittle product, the polymer chains being disposed generally near one another. In addition, the polymerization is not complete and the 100 unpolymerized monomer, which is generally volatile spreads slowly into the atmosphere and foul smelling.

0026Therefore, according to the invention is added to spread mixture comprising 100 monomer, initiator 101 and the accelerator 103, an intercalation compound Single 104, an elastomeric intermediate compound 105, and a polymer 106. Other compounds may however be introduced into the mixture and in particular, a mineral filler for example, to adjust the whiteness of the polymerized layer obtained. In one example, the mineral filler is a carbonate calcium.

0027The simple intercalation compound is a monomer 104 100 compatible with the monomer but with a radical A chemical intended for preventing the polymer chains adjacent to a distance sufficient to imparting, to the polymerized layer, elasticity and a greater flexibility than that one would 100 obtained with the monomer alone.

0028The elastomeric compound is a spacer 105 difunctional polymer which has the property of intercalated in and between two polymer chains adjacent to a crosslinking of the layer polymerized. The elastomeric segment of compound 105 notably allows fully adjust flexibility polymerized layer without increasing its fragility.

0029Infill compounds 104 and 105 cause Furthermore sufficient distance channels adjacent polymer for polymerization of monomers 100 is complete, the stench being then deleted.

0030The polymer 106 is compatible with the monomer 100, that is to say mixable therewith. It's the cases, particularly when said polymer is a 106 homopolymer of the monomer 100. This is the case, furthermore, when this polymer 106 is a polymer, homopolymer or heteropolymer which dissolves in the monomer 100. Furthermore, the polymer 106 may be derived from the rapid polymerization of a monomer different from monomer 100. Through such monomers, viscosity, during the spreading, can be kept at a level very low.

0031The polymerization reactions are of threshold above which they say are accelerated. This is the chilling effect (or Trommsdorff effect) that is found on acrylic monomers and methacrylic. In practice, this threshold varies between 2 and 20% polymerization of the monomers present in the mixture. Also, if one adjusts advantageously a polymer / (monomer + polymer) mixture spread as a function of the monomer 100, 104, 105 present, their viscosity and their reactivity, the entirely initiator rate 101 and accelerator 103 determined, so that said ratio is between 2/100 and 20/100 or higher, the Polymerization is then immediately accelerated.

0032Choose a polymer / (monomer + polymer) above the threshold of the gel effect presents advantages. This allows, first, to further reduce the total time of polymerization monomers 100, 104, 105. This allows, on the other hand, to limit the amount of total heat liberated by the reaction exothermic polymerization, part of the components of the mixture being already polymerized. This also allows to limit the shrinkage of the material polymerized on the card manufacturing medium and around the micro-module and finally to bring the case appropriate, if the polymer is not a homopolymer of monomer and if said polymer is more flexible than said homopolymer of the monomer, more flexibility and large a plasticizing effect to the polymerized layer obtained.

0033However, choosing a polymer / (monomer + polymer) above the threshold of this gel effect one major drawback: it increases the viscosity of mixed. The distribution of spillage on the map of the manufacturing medium is then carried out more difficult, which requires in particular a spreading the mixture under increased pressure. We Note that this distribution is a problem critical in the manufacture of smart cards which the mold cavities have a very shallow depth which does not facilitate fluid flow.

0034A compromise must be found regarding the viscosity of the mixture spread.

0035Such a compromise is very different depending, in particular, the type of card that is manufactured or, according to the method used for the manufacture of cards of a particular type.

0036For example, in the case of manufacture of contactless cards injection pressure Injection is advantageously low in relation to the fragility of the antenna. Also, the viscosity of the widespread material is selected carefully so that it is sufficiently low not damage the antenna and strong enough to inducing, where appropriate, a gel effect.

0037Similarly, in the case of manufacture of cards non-contact type by simply conforming exemption by example, the process described in patent application French filed September 13, 1994 under the number FR-A-2724477, which offers a distribution of the material provided along the antenna guide, the ratio polymer / (monomer + polymer) is selected so as to it is close to the acceleration threshold polymerization by gel effect, the selected viscosity thus being as low as possible.

0038For against, in the case of manufacture of contact cards injection pressure injection may be more important since there no antenna and the viscosity of the mixture is poured advantageously greater than the above viscosities.

0039In an implementation of the method of the invention shown in Figure 3, the monomer 100, the initiator 101, the accelerator 103, the compound interlayer single 104, the intermediate compound elastomeric polymer 105 and 106 are kept in two storage tanks 13 and 14 in storage conditions such that said monomer 100 is substantially stable over time, that is to say such as the polymerization of said monomer 100 has not place significantly.

0040Of course the number of reservoirs is not limited to two. For example, one can have six different reservoirs, each reservoir comprising a compound 100, 101, 103, 104, 105 or 106.

0041Each tank 13 or 14 may contain a solution comprising one or more compounds following: 100 monomer, initiator 101, accelerator 103, simple intermediate compound 104, compound elastomeric spacer 105, and polymer 106. However, a reservoir 13, 14 may not contain the same time the monomer 100, accelerator 103, and the initiator 101. On the other hand, the initiator 101 is preferably introduced into the solution monomeric less reactive. Finally, reservoirs comprise advantageously, both the monomer 100 and the polymer 106 so that the viscosity of the two solutions are close.

0042Also, in the example of Figure 3, the reservoir 13 S1 has a solution comprising the compounds 100, 101, 104, 105 and 106, while the tank 14 S2 comprises a solution comprising compounds 100, 103, 104, 105 and 106.

0043The reservoirs 13 and 14 are connected to a head by mixing 15 respectively referenced conduits 16 and 17. The flow of mixture M1 in the duct 16 is regulated by a valve 18, while the flow rate of the mixture M2 in line 17 is regulated by a valve 19. The mixing of solutions S1 and S2, and therefore, the initiator 101 and accelerator 103 is performed in the head 15 mixture in a ratio S1 / S2 controlled by valves 18 and 19. This mixture has a temperature tmel .. In one example, Tmel. is 25 ° C.

0044Given that the final mixture comprising both the initiator 101 and the accelerator 103 reacts quickly and that the polymerized layer obtained can be thermoset (crosslinked) and not soluble, is advantageously used a mixing head 15 high-pressure, self-cleaning. However, in the If the polymerized layer obtained is thermoplastic (uncrosslinked) and soluble it is possible to use a low-pressure mixing head.

0045In the embodiment shown in Figure 3, the spreading is simply dispense the mixture from the mixing head 15 and passed through conduit 20 on a manufacturing support 21 cards 1. The support 21 is then formed an open cavity 22 of a mold half 23, said ring disposed on a film 24 for forming a bottom layer of the card body 3. The spraying is performed under a reduced pressure, the order of atmospheric pressure.

0046However, in other embodiments, the manufacturing medium 21 is formed of a honeycomb framework such as that described in patent application French filed February 24, 1994 under number 94 02130 and in other embodiments still, the spreading is injected under pressure in a closed cavity of a mold to the card format or layer that is to be obtained.

0047Of course, the micromodule 2 and, where appropriate, the antenna 12 can be present during the spreading on the support 21. They may, however manufacturing be inserted into the common mixture, while polymerizing said mixture is not sufficient to bring its viscosity to excessive values, greater than about 10,000 cps.

0048Laminating the mixture spread can be performed, for example, between two rollers to the rapid achievement of predetermined thicknesses of the body Map. Moreover, such lamination does designs with viscosities and velocities of particularly suitable polymerization and compatible, in particular, with a spread without flow, subsequent to said lamination, on a lower film, and with the recovery of a set lower film - laminated mixture by a second film for forming a top layer of the body of map.

0049Moreover, lamination can be carried out after a step of spreading in an open cavity a ring mold, and after the application of a film higher for forming a top layer of card body, following the demoulding and cutting films from below and from above. Note that, in this case, the applied films adhere naturally to spread mixture, the polymerization of said materials is not at the stage of the application of such films, completely finished.

0050Furthermore, a boot by radiation can be made once the mixture has been poured, for example, by opening an open cavity manufacturing medium 21 of a card. it will be noted if the mixture of the monomer 100, the initiator 101, of the accelerator 103, compounds 104, 105 and polymer 106, occurs directly on the support manufacture of the card 1, the mixing steps, of aforementioned spreading and activation of the process of the invention are then combined.

0051According to the invention, valve sets 18, 19 allow, by varying their openings, to choose easily a compromise between all the constraints cited in order to obtain a satisfactory product. this point of view, the solution of the invention is well better than the old solutions listed. In Indeed, therewith, with each new form or each new strain, surface appearance edit for example, had to redo many tedious tests, build many molds before select a suitable method and mold. grace the process of setting options as the invention good compromises are achieved quickly through simple steps of relative adjustment. Such compromises have allowed the development of methods of card manufacturing in which materials thermosetting polymerize at temperatures below 70 ° C and about 50 ° C approximately, while the viscosity of the material spilled is less than 10,000 mPa · s or 5000 mPa · s

0052For the practice of the invention, advantageous to use a mixture based on a monomer acrylic or methacrylic acid. In particular, following monomers are used:<ul><li>methyl methacrylate (MMA),</li><li>Tri- ethyl methacrylate (ETMA)</li><li>2 Hydroxyethyl methacrylate (HEMA),</li><li>Methacrylic acid ester (C13-MA)</li><li>Isobornyl methacrylate (IBOMA)</li><li>Isobornyl acrylate (IBA)</li><li>Dicyclopentenyloxyethyl methacrylate (DPOMA)</li><li>Tetrahydrofurfuryl methacrylate (THFMA)</li><li>Methacrylate, n-butyl (BMA),</li><li>Benzyl methacrylate (BNMA) </li><li>2-dimethylaminoethyl methacrylate (DMAEMA),</li><li>1, 4-butanediol dimethacrylate (BDDMA),</li><li>diethylene glycol dimethacrylate (TEGDMA), - Diurethane dimethacrylate (TMDI),</li><li>1, 12 dodecanediol dimethacrylate (DDDMA) and</li><li>Triméthyiolpropantriméthacrylate (TMPTMA).</li></ul>

0053Now consider the example of methacrylate methacrylate (MMA). Polymethyl methacrylate (PMMA), obtained by polymerization of MMA is particularly suitable for the coating of inserts.

0054However, the polymerization of MMA is known to be highly exothermic and to present a shrinkage requiring, in the field of manufacture of cards, selecting good compromise by detailed settings according to the type of card and the process chosen.

0055In the presence of a simple radical initiator such a peroxide, or an ultra-violet radiation, MMA polymerized and is then obtained PMMA. However, This polymerization is slow. For example, it is of the order of 45 min. in the presence of peroxide benzoyl.

0056Also, it accelerates the polymerization of MMA by a tertiary amine such as, for example, N, N-bis (2-hydroxyethyl) -p-toluidine). With this amine the polymerization time is significantly decreased. It is of the order of 15 minutes. Nevertheless, the product obtained proves brittle, found a number large bubbles, and a foul smell spreading.

0057Also, using triethylene glycol monomethyl methacrylate (TEGMA) or as HEMA single intercalation compound and polybutadiene dimethacrylic (PBDM) as intercalation compound elastomeric, adjusting the flexibility of the layer polymeric or map obtained and avoids the release of odors.

0058Furthermore, by adding, in the mixture, PMMA, a compatible polymer with MMA, or a monomer which polymerization is extremely fast, such as, example, a cyanoacrylate, we immediately reached or quickly, during mixing, a ratio polymer (monomer + polymer) of about 20% and the polymerization time is then decreased by the effect of gel. In practice, the overall polymerization time is reached is of the order of 6 min ..

0059Moreover, it is advantageously introduced into The mixture, a titanium dioxide filler (TiO₂) in to whiten the polymerized layer obtained.

0060The following examples are given by way Illustrative no way limit the invention.

0061In a first example relating, in particular, the manufacture of contactless cards by simply exemption in an open cavity, S1 solutions S2, stored at room temperature in reservoirs 13 and 14, have the following composition, percentages being by weight:<tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S1:</entry></row><row><entry align="left">MMA (100)</entry><entry align="left">53.3%</entry></row><row><entry align="left">amine (103)</entry><entry align="left">4.6%</entry></row><row><entry align="left">PMMA (106)</entry><entry align="left">33.3%</entry></row><row><entry align="left">TiO₂</entry><entry align="left">8.6%</entry></row></tbody></tgroup></table></tables><tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S2:</entry></row><row><entry align="left">MMA (100)</entry><entry align="left">41.5%</entry></row><row><entry align="left">peroxide (101)</entry><entry align="left">7.7%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">41.5%</entry></row><row><entry align="left">TiO₂</entry><entry align="left">9.2%</entry></row></tbody></tgroup></table></tables>

0062If the mixing is carried out at tmel. equal to room temperature, 10.5 g of S1 with 6.5 g of S2, a mixture M obtained whose composition is the Next, the percentages being given by weight:<tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">M:</entry></row><row><entry align="left">MMA (100)</entry><entry align="left">48.8%</entry></row><row><entry align="left">peroxide (102)</entry><entry align="left">2.9%</entry></row><row><entry align="left">Amine (103)</entry><entry align="left">2.9%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">15.9%</entry></row><row><entry align="left">PMMA (106)</entry><entry align="left">20.6%</entry></row><row><entry align="left">TiO₂</entry><entry align="left">8.8%</entry></row></tbody></tgroup></table></tables>

0063The polymerization of this mixture is effected in less than 6 min. at a temperature below 50 ° C.

0064At this temperature, and the temperature higher, MMA is liquid and its viscosity is less than about 100 mPa · s. The viscosity of this monomer is much lower than the viscosities of thermoplastic materials used in the methods prior art techniques for manufacturing cards which exceed 10,000 mPa.s.

0065Of course, the quantities of MMA, PMMA, amine and peroxide are adjusted in the solutions S1 and S2 and the mixture M, through the valves 18 and 19. Thus, we have, through the aforementioned constituents combined together in adjustable proportions, means simple to obtain a rapid development of a mold and obtaining an optimal method, acceptable industrially. If Tmel. and TREP. are of the order of room temperature, the maximum temperature obtained during the polymerization increases, in such conditions, up to approximately 45 ° C while viscosity of the mixture at TREP., of the order of 1000 mPa.s ..

0066In a second example, it causes the gel effect by triggering the rapid polymerisation cyanoacrylate monomer (CNA) anionically thanks the intervention of a basic catalyst: an amine. Upon mixing, the PMMA / report (CNA + MMA + PMMA) is not sufficient to trigger the effect of gel. However, the amine triggers a polymerization , practically instantaneous, NAC in polycyanoacrylate (PCNA). Also, the (PMMA + PCNA) / (MMA + PMMA + PCNA) is sufficient to generate a gel effect in the mix and accelerate the polymerization of MMA activated by all peroxide / amine. The solutions S1 and S2, stored at room temperature in reservoirs 13 and 14, have the following composition, percentages being by weight:

S1:

0067<ul><li>MMA (100) 48.4%</li><li>peroxide (101) 3.2%</li><li>NAC (106) 16.1%</li><li>PMMA (106) 32.3%</li></ul>

S2:

0068<ul><li>MMA (100) 57.7%</li><li>amine (103) 3.8%</li><li>PMMA (106) 38.5%</li></ul>

0069If we perform at Tmel. equal to the temperature room, the mixture of 10.3 g of S1 with 8.7 g of S2, we obtain a mixture M having the composition the following, the percentages being given by weight:

M:

0070<ul><li>MMA (100) 52.7%</li><li>peroxide (102) 1.75%</li><li>amine (103) 1.75%</li><li>PCNA (106) 8.7%</li><li>PMMA (106) 35.1%</li></ul>

0071The polymerization of this mixture is then carried out in less than 5 min. at a temperature of the order of 55 ° C, the increase of 10 ° C compared to above 45 ° C is due in particular to the NAC polymerization.

0072In a third example, was introduced mixture of HEMA.

0073The solutions S1 and S2, stored at the temperatures room in the tanks 13 and 14 have then following composition, the percentages being given a weight.<tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S1:</entry></row><row><entry align="left">MMA (100)</entry><entry align="left">15.8%</entry></row><row><entry align="left">peroxide (101)</entry><entry align="left">3.5%</entry></row><row><entry align="left">HEMA (104)</entry><entry align="left">60.7%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">20%</entry></row></tbody></tgroup></table></tables><tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S2:</entry></row><row><entry align="left">MMA (100)</entry><entry align="left">20%</entry></row><row><entry align="left">amine (103)</entry><entry align="left">1.9%</entry></row><row><entry align="left">HEMA (104)</entry><entry align="left">61.9%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">16.1%</entry></row></tbody></tgroup></table></tables>

0074If one carries out, tmel equal to the temperature room, the mixture of 10 g of S1 with 10 g of S2, we M then obtains a mixture whose composition is the Next, the percentages being given by weight.

M:

0075<ul><li>MMA (100) 20%</li><li>peroxide (102) 1.75%</li><li>amine (103) 0.95%</li><li>HEMA (104) 61.3%</li><li>PBDM (105) 16.0%</li></ul>

0076HEMA is, ultimately, a compound elastomeric spacer. Also, the polymerization of MMA will be total and no bad smell does emerge.

0077In a fourth example, the MMA was removed. The solutions S1 and S2, stored at the temperature room then have the following composition, percentages being by weight.<tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S1:</entry></row><row><entry align="left">HEMA (100)</entry><entry align="left">76%</entry></row><row><entry align="left">peroxide (101)</entry><entry align="left">4%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">20%</entry></row></tbody></tgroup></table></tables><tables><table><tgroup cols="2"><tbody><row><entry namest="1" nameend="2">S2:</entry></row><row><entry align="left">HEMA (100)</entry><entry align="left">77.4%</entry></row><row><entry align="left">amine (103)</entry><entry align="left">2.4%</entry></row><row><entry align="left">PBDM (105)</entry><entry align="left">20.2%</entry></row></tbody></tgroup></table></tables>

0078If one carries out, tmel equal to the temperature room, the mixture of 10 g of S1 with 10 g of S2, we M then obtains a mixture whose composition is the Next, the percentages being given a weight. M:<ul><li>HEMA (100) 76.7%</li><li>peroxide (101) 2%</li><li>amine (103) 1.20%</li><li>PBDM (105) 20.1%</li></ul>

0079However, the adhesion of the above mixture is low.

0080The compromise favors the settings selected Casual factors such as viscosity and speed or the overall polymerization time allow quickly select the appropriate method for the manufacture of cards and the mold used.

0081The maps obtained by the method according the invention with use of acrylic or system methacrylic are, whether in contacts, or without, flexible, hard, resistant to shocks, and present a good surface. The choice of monomers or polymeric modifiers such as, for example, acrylate or butyl methacrylate, allow the adjustment of the abovementioned qualities maps.

0082Of course, different reagent systems monomers / polymers, thermosetting, allowing rapid synthesis of polymerized compounds via a extender activated chain reaction, can be applied according to the method of the invention and, in particular, acrylic or methacrylic systems other than MMA / PMMA system, epoxides systems β that polymerize, for example, cationically, and systems polyurethanes which cure by example, by heating at temperatures above a reaction limit temperature.

0083Monomers 100 are chosen for their characteristics and their impact on the film 6. polymerized MMA is selected for membership and rigidity, THFMA is selected for membership, IBOMA is selected for the temperature resistance and TMPTMA, for rigidity. With a monomer mixture 100, is and find a compromise adhesion, stiffness and the temperature resistance of the layer 6.