HK1069469B - Ic card - Google Patents

Description

IC card

Technical Field

The present invention relates to an information recording card with an information recording medium used for ID cards (identification cards), membership cards, prepaid cards, cash cards, monthly tickets, and the like, and more particularly to a non-contact IC information recording card (information recording-contact IC card) having a function of recording electronic data information and visible information.

Background

Information recording cards including identification cards and credit cards using a method of magnetically or optically reading data have been widely used. However, due to the spread of technology, data in a magnetic card is easily changed or a counterfeit magnetic card is spread. In fact, the losses that people suffer from counterfeiting magnetic cards are increasing day by day, and they raise social problems related to personal privacy. For this reason, in recent years, as an article for controlling personal data, IC cards made of resin having an IC chip embedded in a card substrate have attracted attention for their large data capacity and the possibility of storing encoded data.

For the exchange of information between the IC circuit and the external data processing device, the IC card is provided with a connection terminal for connecting them electrically and mechanically. However, the IC card has various problems such as necessity of securing airtightness of the IC circuit, avoidance of influence of electrostatic discharge, possibility of malfunction of connection between terminal electrodes, and complexity of mechanism of the reader/writer. Also, in some cases, the IC card must be manually inserted or mounted on the reader/writer, thereby making the transaction inefficient or such an operation cumbersome. Therefore, it is urgently required to develop a non-contact IC card (non-contact IC card) which does not require a cumbersome operation procedure and can exchange information with a portable remote data processing apparatus.

In order to meet this demand, a noncontact IC card having an antenna using electromagnetic waves and an IC chip having a storage and operation function on a card substrate has been developed. In such an IC card, an integrated circuit is driven by an induced electromotive force in a card base antenna excited by an external electromagnetic wave from a reader/writer, and there is no battery power source in the card, thus giving the card excellent flexibility. In some applications, it is attempted to embed a thin battery, such as a paper-printed battery, in the card for expanding the communication distance or utilizing a higher frequency band. Of course, a magnetic card without a battery is more popular from the viewpoint of cost reduction and popularization and application.

In order to record information on the card, digital recording is realized by a recordable IC chip provided on a part of the card. To display or read the data recorded in the card, a special reading instrument is required to read the recorded data. So that the general user cannot read the data by himself. For example, a member is added with a high prize or score in a membership card, and if it is recorded only on the card, information such as a separate information note (information note) is required. In view of this, the demand for conveniently displaying data records is increasing.

In order to meet this demand, a technique has been developed in which a reversible display layer (for example, a reversible thermosensitive recording layer, hereinafter referred to as a "thermosensitive recording layer") is provided on the surface of a card substrate, the reversible display layer is made of a polymer/low-molecular-weight type material, the display layer includes organic low molecules dispersed in a resin binder, and display is performed using an opaque-transparent contrast. The polymer/low-molecular type reversible display medium is composed of a support such as a plastic sheet/color layer/recording layer (polymer/low-molecular)/protective layer.

Further, currently, in order to reduce the cost, there has been an attempt to adopt a bare chip mounting method in which an IC chip is directly incorporated into a card by providing electrodes for connecting an antenna and the IC chip on a sheet-type insulating substrate. In this case, a face down bonding method (face down bonding method) is employed in which a protruding portion called a bump made of solder or gold is formed on an electrode portion of a circuit forming surface of an IC chip, and the electrode portion is connected through the bump. This connection is used to fill the gap between the IC chip circuit surface and an insulating substrate with an anisotropic conductive film, a resin containing conductive particles such as a heterogeneous conductive resin, or a gap between the filling material and the circuit surface.

Incidentally, in an IC card, in order to secure reliability of operation of an IC chip, a sealing resin different in hardness from a card base is used to protect the IC chip. In addition, in order to avoid all data loss due to mechanical breakage of the IC card, a task of improving the mechanical strength of the IC card in the case of bending and forming a point pressure at a certain point of impact or the like is proposed. To accomplish this task, a structure has been considered in which a reinforcing sheet is provided on a sealing resin to prevent a connecting portion of an IC chip or the IC chip itself from being broken.

The IC card is generally manufactured as follows. First, a resin sheet is printed by a known printing method such as offset printing, gravure printing or screen printing, and protective sheets made of a highly transparent film resin are laminated on both surfaces of the printed resin sheet. Then, an IC module is placed between these sheets, they are thermally fused by hot pressing, and then punched into a card shape with a die of a predetermined size. Finally, characters called embossed characters (letterpress) are embossed on the card and made available to the user.

However, the IC card having the reinforcing material described above has the following problems. Particularly, when a reinforcing sheet (reining sheet) is used together with a sealing resin having a curing shrinkage property, the reinforcing sheet may be deformed due to the curing shrinkage of the sealing resin. For this reason, when the IC module with the reinforcing sheet provided on the IC chip is sealed between the resin sheets (card substrates) with the sealing resin, the deformation of the reinforcing sheet cannot be satisfactorily eliminated by the card substrate, and thus the card substrate surface may become uneven.

In a card substrate having an uneven surface, when a printing operation is performed on a thermosensitive recording layer, a space will be generated between the thermosensitive recording layer and a thermal head, so that the thermosensitive recording layer cannot be satisfactorily heated, and there is a possibility that a problem similar to image recording loss occurs.

An object of the present invention is to provide an IC card which reliably protects an IC chip with a reinforcing sheet while keeping the card base surface flat, and thus can reliably print a reversible display layer provided on the card base surface.

Disclosure of Invention

In order to achieve the above object, the present invention provides an IC card comprising: an IC module including an IC chip mounted on an insulating substrate, and a reinforcing sheet provided on the IC chip via a sealing resin for sealing the IC chip; a card substrate composed of a sealing resin for sealing the IC module; the IC card is characterized in that a reinforcing film pattern (Reinforcement film pattern) having an opening for exposing a mounting portion of an IC chip is provided on at least one surface of an IC chip mounted surface and a non-mounted surface of an insulating substrate.

In such an IC card, since a reinforcing film pattern for an IC module with an opening for exposing a mounting portion of an IC chip on an insulating substrate is provided, the insulating substrate around the periphery of the IC chip is reinforced without increasing the height of the IC module. Therefore, the reinforcing sheet is hardly deformed by curing shrinkage of the sealing resin sealing the IC chip. For example, in a card substrate composed of hot-pressed laminated thermoplastic sheets (IC modules) with an IC module interposed therebetween, the reinforcing sheet is hardly deformed even when the sealing resin is subjected to a temperature higher than its glass transition temperature during hot pressing. Therefore, the flatness of the surface of the card base sealing the IC module including the portion surrounding the IC chip mounting portion can be ensured. Therefore, the surface flatness of the reversible display layer provided on the card substrate is also ensured.

Drawings

FIG. 1 is a cross-sectional view showing the structure of an example of an IC card of the present invention;

FIG. 2 is a cross-sectional view of an important part of the IC module of the invention, showing an example of the structure;

FIG. 3 is a circuit diagram of the present IC card;

FIG. 4 is a plan view of an IC module structure;

FIG. 5 is a plan view of an example of a pattern structure of a reinforcing thin film according to the present invention;

FIG. 6 is a plan view of another example of a reinforcing film pattern structure in the present invention;

FIG. 7 is a plan view of still another example of a pattern structure of a reinforcing film in the present invention;

FIG. 8 is a cross-sectional view of an important part of an IC module of the present invention, showing another example of the structure;

FIG. 9 is a cross-sectional view showing the structure of another example of an IC card in the invention;

FIG. 10 is a plan view of the reinforced film pattern formation and structure of examples 1 and 9;

FIG. 11 is a plan view of the reinforcing film pattern formation and structure of examples 2 and 10;

FIG. 12 is a plan view of a reinforcing film pattern formation and structure in examples 3 and 11;

FIG. 13 is a plan view of the reinforcing film pattern formation and structure of examples 4 and 12;

FIG. 14 is a plan view of an enhanced film pattern formation and structure of examples 5 and 13;

FIG. 15 is a plan view of the reinforcing film pattern formation and structure of examples 6 and 14;

FIG. 16 is a plan view of an enhanced film pattern formation and structure of examples 7 and 15;

FIG. 17 is a plan view of an enhanced film pattern formation and structure of examples 8 and 16;

FIG. 18 is a plan view of a reinforcing film pattern formation and structure of example 17;

FIG. 19 is a plan view of a reinforcing film pattern formation and structure of example 18;

FIG. 20 is a plan view of a reinforcing film pattern formation and structure of example 19;

FIG. 21 is a plan view showing the formation and structure of a reinforcing film pattern in comparative example 3 and comparative example 6;

FIG. 22 is a plan view showing the formation and structure of a reinforcing film pattern in comparative example 4 and comparative example 7;

fig. 23 is a plan view showing the formation and structure of the reinforcing film pattern in comparative example 5 and comparative example 8.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a cross-sectional view of an example of an IC card of the present invention, and fig. 2 is an enlarged cross-sectional view of an important part of an IC module constituting the IC card. First, an IC card structure of an embodiment of the present invention is described with reference to these drawings.

The IC card shown in these drawings includes an IC module 1, a card base 2 enclosing the IC module 1, and a reversible recording layer (reversible recording layer)3 provided on at least one surface of the card base 2.

The IC module 1 includes an insulating substrate 11 as a base material and a circuit pattern 12 formed on one principal surface of the insulating substrate 11 to constitute an antenna or the like. The reinforcing film patterns 13, 13' are provided on at least one surface (provided on both surfaces in the present embodiment) of the insulating substrate 11. The unique structure of the present invention is the reinforcing film pattern 13, 13'. The IC chip 14 is mounted on the surface of the insulating substrate 11 on which the circuit pattern 12 is formed so as to be connectable to the circuit pattern 12.

Further, a sealing resin 15 for sealing the IC chip 14 and a reinforcing sheet 16 for covering the entire upper surface of the IC chip with the sealing resin 15 are provided on the insulating substrate 11.

The structure of each part of the IC card having the above-described structure will be described in detail below.

First, the insulating substrate 11 as a base material constituting the IC module 1 is composed of a single material. For example, from polyimide; polyesters such as polyester, polyethylene terephthalate, or polyethylene naphthalate; polyolefins, such as polypropylene; cellulose, such as cellulose triacetate or cellulose diacetate; vinyl resins such as acrylonitrile-butadiene-styrene resin, acrylonitrile-styrene resin, polystyrene, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polyethyl methacrylate, polyvinyl acetate or polyvinyl alcohol; a polycarbonate; or a mixture thereof, and any organic material having insulating properties may be used.

The circuit pattern 12 formed on the insulating substrate 11 constitutes a circuit portion within the IC card.

Fig. 3 shows a basic circuit configuration of the IC card. As shown in the figure, the circuit configuration of the IC card is such that the rectifying diode 43, the filter capacitor 44 and the IC chip 14 are connected to a resonance circuit including the antenna coil 41 and the tuning capacitor 42. As shown in fig. 4, the antenna coil 41 is constituted by the circuit pattern 12 formed on the insulating substrate 11, and the tuning capacitor 42, the rectifying diode 43, and the smoothing capacitor 44 may be constituted by either the circuit pattern 12 or may be incorporated in the IC chip 14.

The circuit pattern 12 may be obtained by forming a conductive material layer composed of copper, aluminum, gold, or silver on the insulating substrate 11 by, for example, coating, vapor deposition, or the like, and etching the conductive material layer to form a pattern in the layer. The circuit pattern 12 may contain a large amount of conductive particles or foil-type particles (fol-form particles) treated with a conductive metal, and an organic polymer/organic low-molecular substance or its reactant or an inorganic binder (water glass, silicon binder, etc.) for binding the particles together, or may be patterned on the material according to a printing method (screen printing method, offset printing method, etc.) to produce a circuit pattern.

Further, alternatively, the circuit pattern 12 in a stripe shape may be bonded to the insulating substrate 11 by an adhesive; or a conductive foil is bonded to the insulating substrate 11 by an adhesive and etched into a circuit pattern 12. In this case, an organic polymer/organic low-molecular substance or a synthetic resin thereof may be used as the binder. For example, a single thermoplastic resin material such as a polyester urethane resin; a polyurethane resin; a polyester resin; vinyl resins, such as acrylonitrile-butadiene-styrene resins, acrylonitrile-styrene resins, polystyrene, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polyethyl methacrylate, polyvinyl acetate, or polyvinyl alcohol, polycarbonate, or mixtures thereof. In addition, conventionally known binder resins, such as thermosetting resins, e.g., phenol resins, epoxy resins or silicone resins, can also be used. As the organic low-molecular active agent, a compound having at least two or more isocyanate groups (-N ═ C ═ O) per molecule or a compound having an epoxy functional group can be used, and a mixture of a compound having a reactive functional group (compound a reactive functional group) and a compound having an active functional group (compound a functional group a reactive functional group) such as a hydroxyl group or an amino group or the like can also be used without any problem.

Referring again to fig. 2, the reinforcing film patterns 13, 13 'provided on both surfaces of the insulating substrate 11 have openings 13a, 13 a', respectively, which expose IC chip mounting portions provided at positions corresponding to the periphery of the IC chip 14.

The openings 13a, 13 a' are larger than the IC chip 14, respectively, and the IC chip 14 is disposed in the opening 13a of the reinforcing thin film pattern 13 on the mounting surface (mounted surface). On the other hand, the reinforcing thin film pattern 13 'is provided on a non-mounted surface so that the IC chip 14 is disposed inside the opening 13 a'. The periphery of each opening 13a, 13 a' is located inside the periphery of the reinforcing sheet 16 provided on the IC chip 14. Therefore, the shapes of the openings 13a, 13 a' depend on the shape of the IC chip 14 and the shape of the reinforcing sheet 16. For example, as shown in fig. 5, if the IC chip 14 has a square shape and one side of the IC chip 14 is "a", the openings 13a and 13 a' on the reinforcing thin film pattern 13 have a rectangular shape (e.g., a square shape) with one side "b" of about (a +0.1) to (a +1) mm, respectively. For the sake of explanation, the reinforcing film pattern 13 'is transferred onto the non-mounting surface in fig. 5, but in practice, the reinforcing film pattern 13' on the non-mounting surface may be superposed on the reinforcing film pattern 13 on the mounting surface.

Further, the reinforcing film patterns 13, 13 ' have an outer peripheral shape such that at least a part of the outer peripheral edges of the reinforcing film patterns 13, 13 ' are overlaid on the outer peripheral edge of the reinforcing sheet 16, preferably "projected" from the outer peripheral edge of the reinforcing sheet 16 so that the openings 13a, 13a ', the IC chip 14 and the reinforcing sheet 16 are disposed with their centers aligned with each other. It is further preferred that the outer periphery of the reinforcing film pattern 13, 13' is uniformly "protruded" from the outer periphery of the reinforcing sheet 16. An example is described below. When a square IC chip 14 having a side length "a" of 4mm is placed at the center of the opening 13a, 13a ' of the reinforcing film pattern 13, 13 ' and a circular reinforcing sheet 16 having a diameter "c" of 7mm is placed on the IC chip 14, the outer periphery of the reinforcing film pattern 13, 13 ' has a rectangular shape so that the diagonal line thereof coincides with the diameter of the reinforcing sheet 16, and preferably has a shape capable of covering the rectangular shape.

The reinforcing film patterns 13, 13' with the above-described shape may be formed of a conductive material or an insulating material.

When the reinforcing film patterns 13, 13' are composed of a conductive material, the reinforcing film pattern 13 on the IC mounting surface is patterned to be insulated from the circuit pattern 12. Therefore, the bypass pattern 13b is provided at the connection portion between the circuit pattern 12 and the IC chip 14 in the reinforcing thin film pattern 13. In this case, the reinforcing thin film patterns 13 and 13' each have a region in which communication characteristics (communication characteristics) of the antenna formed of the circuit pattern 12 can be secured.

Particularly when the reinforcing film pattern 13' on the non-mounting surface of the IC is patterned to have a shape in which the reinforcing film is not superposed on the circuit pattern 12, the communication characteristics of the antenna constituted by the circuit pattern 12 can be ensured. Therefore, it is preferable to provide a bypass pattern 13b 'in the reinforcing film pattern 13' at the connecting portion between the circuit pattern 12 and the IC chip 14.

When the reinforcing film pattern 13 'on the non-mounting surface of the IC is composed of a conductive material, the reinforcing film pattern 13' has a structure divided into a plurality of parts as shown in fig. 6. In this case, the reinforcing film pattern 13' is divided into portions each of which is overlaid on the circuit pattern 12 on the IC mounting surface. Particularly when the input and output portions of the circuit pattern 12 connected to the IC chip 14 are provided on the reinforcing film pattern 13 ', the reinforcing film pattern 13' is divided into two portions, i.e., a portion superposed on the input portion of the circuit pattern 12 and a portion superposed on the output portion of the circuit pattern 12. Therefore, even when the circuit pattern 12, the insulating substrate 11 and the reinforcing thin film pattern 13' form a capacitor, the influence thereof on the communication characteristics can be reduced, and thus good communication characteristics can be obtained.

Specifically, if the reinforcing film pattern 13 on the IC mounting surface is made of the same material as the circuit pattern 12, the reinforcing film pattern 13 and the circuit pattern 12 can be formed in the same step, and therefore, in the production process of the IC card, the new portion of the reinforcing film pattern 13 can be provided without increasing the number of steps.

On the other hand, when the reinforcing film patterns 13, 13 ' are formed of an insulating film, there is no particular limitation as to the formation of the outer periphery of each reinforcing film pattern 13, 13 ', as described above, as long as at least a part of the outer periphery of the reinforcing film pattern 13, 13 ' is located outside the outer periphery of the reinforcing sheet 16. Therefore, the degree of freedom in designing the reinforcing film patterns 13, 13' is improved. Further, in this case, the structure of the IC mounting surface on the insulating substrate 11 may be such that the circuit pattern 12 is provided by the reinforcing thin film pattern 13, or the reinforcing thin film pattern 13 is provided on top of the circuit pattern 12.

Further, as shown in fig. 7, in the reinforcing thin film pattern 13 on the mounting surface of the IC chip 14, an alignment mark 13c is formed in advance for mounting the IC chip 14 on the insulating substrate 11 on which the reinforcing thin film pattern 13 is formed. The reinforcing film pattern 13 with the alignment mark 13c is made of either a conductive material or an insulating material.

Further, as shown in fig. 2, the IC chip 14 includes a protruding electrode 14a provided on, for example, the surface on which the circuit is formed, and the IC chip 14 is mounted on the insulating substrate 11 by face-down bonding, whereby the protruding electrode 14 is connected to the circuit pattern 12 by the anisotropic conductive adhesive layer 17. The anisotropic conductive adhesive layer 17 is composed of conductive particles dispersed in an adhesive resin, and has conductivity only in the thickness direction.

As the adhesive resin forming the anisotropic conductive adhesive layer 17, a single material, for example, a urethane resin; a polyester polyurethane resin; vinyl resins such as acrylonitrile-butadiene-styrene resin, acrylonitrile-styrene resin, polystyrene, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polyethyl methacrylate, polyvinyl acetate or polyvinyl alcohol; a polycarbonate resin; or epoxy resins, or mixtures or compounds thereof.

As the conductive particles dispersed in the binder resin, gold (Au), nickel (Ni), aluminum (Al), tin (Sn) or particles obtained by treating the surface of non-conductive particles, hollow particles, or a foil subjected to conductive treatment (physical or chemical treatment with gold, nickel, aluminum, or tin) may be used. These conductive particles are dispersed in a binder resin in a state of having a non-conductive surface treatment with an organic substance or the like. During the mounting of the IC chip 14, when the IC chip 14 is pressurized and heated, the non-conductive processed layer on the surface of the non-conductive processed particles is broken, the conductive layer is exposed, and electrical connection is formed between the IC chip 14 and the circuit pattern 12.

A support pattern (support pattern)18 for filling a gap between the IC chip 14 and the insulating substrate 11 is provided below the IC chip 14. The support pattern 18 may be formed, for example, in the same manner as the formation of the circuit pattern 12. It is noted that the support pattern 18 and the reinforcing film pattern 13 are separated on the mounting surface.

A sealing resin 15 for sealing the IC chip 14 is introduced to seal the IC chip 14 mounted on the insulating substrate 11. As the sealing resin 15, an epoxy resin, a silicone resin, or a thermosetting resin of phenol can be used. In order to suppress stress on the IC chip 14 due to volume shrinkage caused by the thermosetting reaction, a single material of a filler, hollow particles, or a foil, or a mixture thereof is dispersed in the sealing resin 15. In order to suppress the stress caused by shrinkage, the size of the filler, hollow particles or foil to be used or the size and mixing ratio of the particles may be appropriately adjusted.

The reinforcing sheet 16 is provided on the sealing resin 15 and thus can be bonded to the sealing resin 15. In addition, the reinforcing sheet 16 has a shape that can surely be provided over the entire upper surface of the IC chip 14 having a shape in which a planar pattern is rectangular, for example. For example, the reinforcing sheet 16 may be a circle having a radius larger than the maximum continuous length (e.g., diagonal length) of the planar pattern of the IC chip 14, or a substantially circular shape obtained by cutting a portion from the circle.

The reinforcing sheet 16 with the above-described special shape may be composed of a metal material, and particularly preferably of a material having a vickers hardness of 200 or more. The Vickers hardness can be determined according to the measurement method described in JIS-Z2244, which is measured with a Vickers hardness tester specified in JIS-B7725.

Examples of the material having a Vickers hardness of 200 or more include non-ferrous metal materials such as Cu-Sn-P, Ni-Cu-Zn and Cu-Be-Ni-Co-Fe; nickel alloy materials such as Ni-Co, Ni-Cr, and Ni-Mo-Cu; nickel-iron alloy materials, such as Ni-Fe; titanium, molybdenum, and stainless steel materials such as SUS304, SUS301, SUS316, SUS631, ASL350, SUS430, and SUS 420; and carbon steel, for example, SK material, a material having further increased hardness obtained by heat-treating the above material can also be used.

It is desirable that the reinforcing sheet 16 be formed of the above-mentioned material and have a thickness of 25 μm or more, and in order to obtain an IC card having a thickness within the range specified by ISO (760 ± 80 μm), it is desirable that the upper limit of the thickness of the reinforcing sheet 16 be 100 μm. When the thickness of the reinforcing sheet 16 is within this range, the reinforcing sheet 16 with the above-specified shape and size is hardly deformed and has satisfactory strength.

In the above description, the IC module 1 has a structure in which the reinforcing sheet 16 is provided only on the IC chip 14 on the mounting surface of the insulating base 11, but of course, the structure of the IC module is not limited thereto, and may be a structure as shown in fig. 8, that is: a reinforcing sheet 16 'may also be provided on the non-mounting surface of the IC chip 14 on the insulating substrate 11 by the sealing resin 15'. In this IC module 1 ', the reinforcing sheet 16' provided on the non-mounting surface is placed on the back surface of the substrate at a position corresponding to the IC chip 14, and thus back-to-back with the reinforcing sheet 16. The reinforcing sheet 16' may have the same shape as the reinforcing sheet 16 formed on the mounting surface, but of course, need not be. Also in this case, the shape and structure of the reinforcing film patterns 13, 13 'for the reinforcing sheet 16' are similar to those for the reinforcing sheet 16.

The above-described card substrate 2 for sealing an IC module 1 or an IC module 1' (hereinafter, both cases will be collectively referred to as IC module 1) shown in fig. 1 includes: for example two thermoplastic sheets 21, 21 'hot-pressed together and an IC module 1 arranged between the thermoplastic sheets 21, 21'.

The thermoplastic resin sheets 21, 21' may be composed of crystalline thermoplastic resin (crystalline thermoplastic resin) having a crystallinity as low as 5% or less, may be composed of the same material, may be composed of different materials, and may be composed of single layers or laminated layers of the same material, or may be composed of single layers or laminated layers of different materials. Specifically, as the thermoplastic resin sheets 21, 21', a single amorphous resin (amorphous resin) material such as a copolymer of terephthalic acid, cyclohexanedimethanol and ethylene glycol; an alloy of the copolymer and polycarbonate; copolymers of terephthalic acid, isophthalic acid and ethylene glycol; acrylonitrile-butadiene-styrene copolymer resins; a polystyrene resin; polyacrylonitrile resin; a polyvinyl alcohol resin; a polypropylene methyl ester resin; a polymethyl methacrylate resin; a polyvinyl acetate resin; polycarbonate resins, or mixtures thereof. It is also possible to use, instead of the amorphous resin, a double-sided amorphous sheet (double-sided amorphous sheet) prepared from an amorphous resin and a crystalline resin by a co-extrusion method. Further, additives and substances such as polymers may be added to the low crystallinity polyester resin or other resins in an amount of 50% by weight or less than 50%, preferably 15% by weight or less.

In addition to the reversible recording layer 3, for example, a printed layer as a surface layer of the card base 2 is provided, and the printed sheet (printed sheet) is heat-pressed with the thermoplastic resin sheets 21, 21'. In this case, an adhesive may be used in order to improve the adhesion between the thermoplastic resin sheets 21, 21' and the printed sheet at the time of hot melting.

As the sheet material used together with the thermoplastic resin sheets 21, 2', a single material such as polyimide; polyesters such as polyester, polyethylene terephthalate, or polyethylene naphthalate; polyolefins, such as polypropylene; cellulose, such as cellulose triacetate or cellulose diacetate; vinyl resins such as acrylonitrile-butadiene-styrene resin, acrylonitrile-styrene resin, polystyrene, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polyethyl methacrylate, polyvinyl acetate or polyvinyl alcohol; or polycarbonate; or mixtures thereof.

As the binder used together with the thermoplastic resin sheets 21, 21', a single material such as polyester resin; a polyurethane resin; a polyester polyurethane resin; vinyl resins such as acrylonitrile-butadiene-styrene resin, acrylonitrile-styrene resin, polystyrene, polyacrylonitrile, polymethyl acrylate, polymethyl methacrylate, polyethyl acrylate, polyethyl methacrylate, polyvinyl acetate or polyvinyl alcohol; a polycarbonate; or an epoxy resin, or mixtures or compounds thereof.

Next, as for the reversible recording layer 3 formed on the surface of the card substrate 2, a printing operation is performed by causing the print head to sweep the reversible recording layer 3. The reversible recording layer 3 is composed of, for example, a thermosensitive type reversible display layer. In fig. 1, an example is shown in which the reversible recording layer 3 is formed only on the IC mounting surface, however, the reversible recording layer 3 may be formed on at least one surface of the card base 2, that is, at least on one of the IC mounting side and the IC non-mounting side.

The heat-sensitive type reversible recording layer 3 may be selected from either one of polymer/low-molecular type or one of lueco compound type, and the recording layer may be formed to have a thickness of about 4 to 20 μm by a printing method, a coating method, or the like.

The reversible recording layer 3 of the polymer/low-molecular type can be reversibly changed from an opaque layer to a transparent layer according to a change in the crystalline state of an organic low-molecular substance dispersed in a resin matrix. In the reversible recording layer 3 of this type, as examples of the organic low-molecular substance dispersed in the reversible recording layer 3, fatty acids, fatty acid derivatives and alicyclic organic acids, more specifically, saturated and unsaturated fatty acids and dicarboxylic acids, and specific examples of the saturated fatty acids include: myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, nonadecanoic acid, arachic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, and melissic acid; specific examples of the unsaturated fatty acid include: oleic, elaidic, linoleic, sorbic and stearynoic acids. The fatty acid, fatty acid derivative, and alicyclic organic acid are not limited to those described above, and one of the above or a mixture of two or more of the above may be used.

As the resin matrix to be used, a single material such as an acrylic resin, a urethane resin, a polyester resin, a cellulose acetate resin, a cellulose nitrate resin, a vinyl chloride resin, or a vinyl acetate resin, or a mixture thereof or a copolymer thereof may be used. In addition, in order to control the temperature range in which the reversible recording layer 3 becomes transparent, a plasticizer for the resin, a high boiling point solvent, and the like may be added in an amount of 0.1 to 20% by weight, depending on the weight of the resin matrix. Further, in order to improve the resistance of the reversible recording layer 3 against repeated printing and erasure, a curing agent, a crosslinking agent or the like suitable for three-dimensional crosslinking of the resin matrix may be added in an amount of 0.5 to 10% by weight based on the weight of the resin matrix.

On the other hand, the heat-sensitive reversible recording layer 3 of the lueco compound type utilizes a reversible color reaction (reversible color reaction) between the lueco mixture dispersed in the resin matrix and a color developing agent (color developing agent). As a conventional colorless or light-colored lueco compound used in the reversible recording layer 3, there is representatively one of those usually used in pressure-sensitive recording paper, thermal recording paper, photosensitive recording paper, electrothermal recording paper, or thermal drawing paper, such as xanthene (xanthene), spiropyran (spiropyran), lactone, fluoran (fluoran), a sultone compound having a partial skeleton, such as lactone, sultone, or spiropyran (spiropyran), but there is no particular limitation here.

Specific examples of the lueco compound include:

3, 3-bis (p-dimethylaminophenyl) -6-dimethylamino-2-benzofuranone,

3, 3-bis (p-dimethylaminophenyl) 2-benzofuranone,

3, 3-bis (1, 2-dimethylindol-3-yl) -6-dimethylamino-2-benzofuranone,

3-dimethylamino-6-chloro-7-methylfluoran,

3, 3-bis (9-ethylcarbazol-3-yl-5) -dimethylamino-2-benzofuranone,

3-dimethylamino-7-dibenzylaminofluoran,

3-diethylamino-7-chlorofluorane,

3-diethylamino-6-methyl-7-anilinofluoran,

3-piperidino-6-methyl-7-anilinofluoran,

3- (n-ethyl-n-nitrile) amino-6-methyl-7-anilinofluoran,

3-dibutylamino-6-methyl-7-anilinofluoran, and

3- (n-ethyl-n-tetrahydrofuryl) amino-6-methyl-7-anilinofluorane,

the above compounds may be used alone or in combination.

The coloring and decoloring agent is a compound which emits protons by utilizing the effective action of thermal energy, and has both a coloring action and a decoloring action on the lueco compound. In other words, the coloring and decoloring agent has both an acidic group composed of a phenolic hydroxyl group or a carboxyl group and a basic group composed of an amino group, and is acidic or basic according to a change in thermal energy that causes the color development or decoloring of the lueco compound. The basic groups may be present either as functional groups or as part of a compound. Examples of the coloring and decoloring agent having any of a functional group as an acidic group and a functional group as a basic group for the coloring and decoloring agent include: aminobenzoic acid, o-aminobenzoic acid, 4-amino-3-methylbenzoic acid, 3-amino-4-methylbenzoic acid, 2-amino-5-ethylbenzoic acid, 3-amino-4-butylbenzoic acid, 4-amino-3-methoxybenzoic acid, 3-amino-4-ethoxybenzoic acid, 2-amino-5-chlorobenzoic acid, 4-amino-bromobenzoic acid, 2-amino-2-nitrobenzoic acid, 4-amino-3-nitrobenzoic acid, 3-amino-4-cyanobenzoic acid, aminosalicylic acid, diaminobenzoic acid, 2-methyl-5-aminonaphthoic acid, 3-ethyl-4-aminonaphthoic acid, di-aminobenzoic acid, di-amino-benzoic acid, di-methyl-5-aminonaphthoic acid, di-, Nicotinic acid, isonicotinic acid, 2-methylnicotinic acid, and 6-chloronicotinic acid. As the coloring and decoloring agent having a basic group in the form of a part of a basic compound, there are mentioned a salt of a compound having a phenolic hydroxyl group or a carboxyl group or a complex salt of a compound having a phenolic hydroxyl group or a carboxyl group and a compound having an amino group, and examples of a salt or a complex salt including an acid such as hydroxybenzoic acid, hydroxysalicylic acid, gallic acid, or bisphenol acetic acid, and a base such as aliphatic amine, phenylalkylamine, or trienylamine. Specific examples include: p-hydroxybenzoic acid-alkylamine salt, p-hydroxybenzoic acid-phenylalkylamine salt, m-hydroxybenzoic acid-alkylamine salt, methyl p-hydroxybenzoic acid-alkylamine salt, stearyl p-hydroxybenzoic acid-alkylamine salt, bisphenol acetic acid-alkylamine salt, octyl bisphenol acetic acid-alkylamine salt, which may be used alone or in combination. The lueco compound and the coloring and decoloring agent are not limited to these, and one or a mixture of two or more of them may be used.

As the resin matrix, a single resin, for example, an acrylic resin, a polyester resin, a polyurethane resin, polyurea, a melamine resin, polycarbonate, polyamide, polyvinyl, pyrrolidone, polyvinyl alcohol, polyvinyl chloride, or polyvinyl butyral, or a mixture or copolymer thereof can be used. Further, in order to improve the resistance of the reversible recording layer 3 against repeated printing and erasure, a curing agent, a crosslinking agent or the like suitable for three-dimensional crosslinking of the resin matrix may be added in an amount of 0.5 to 10% by weight, based on the weight of the resin matrix. In addition, in order to improve the resistance, an ultraviolet absorber having higher compatibility with the lueco compound may be added.

As a method for producing an IC card with the structure, a melt lamination method (fusion lamination method) by means of hot pressing may be used. In the production of an IC card by the melt lamination method, for example, the IC module 1 is first placed between two thermoplastic resin sheets 21, 21', and then they are placed together between mirror sheets larger than them and integrated by hot-melt pressing (hot-melt pressing). Thus, the IC module 1 is sealed in the card substrate 2. The lens used in this case may be a nickel-chromium plated copper sheet, a stainless steel sheet with a ground surface, or an aluminum sheet with a ground surface.

Then, if necessary, a printed sheet obtained by printing characters or graphics on the resin may be prepared by a known printing method, for example, an offset printing method, a screen printing method, or a gravure printing method. Next, the printed sheet is placed on the card base layer 2, the reversible recording layer 3 is further provided on the printed sheet, and the reversible recording layer 3 and the printed sheet are temporarily fixed on the surface of the card base 2 by using, for example, an ultrasonic welding machine or the like. The resulting laminate is then placed between lenses and fused together by hot pressing.

Then, the integrated card material is peeled off from the lens and punched into a card shape by a single-edged die or a female die to produce an IC card. Further, after punching into the shape of the card, if necessary, characters are embossed on the card by an embosser, and dot tips (tipping) of the embossed characters are colored with a heat conductive foil or magnetic information is encoded on a magnetic stripe, and if necessary, a facial photograph, a bar code, or the like is transferred to the card, thereby obtaining a finished IC card. The printing to the surface of the card base 2 may be printing directly to the surface of the thermoplastic resin sheet 21, 21'.

Alternatively, although not shown, in order to provide a contact IC chip, the card base 2 is cut to form a recess, and then the contact IC chip is embedded in the recess by an adhesive, whereby an IC card having a hybrid (combination) or hybrid (hybrid) of both a noncontact IC (such as the IC chip 14) and a contact IC can be produced.

The IC card thus obtained has a reinforcing film pattern 13, 13 'on the insulating substrate 11 of the IC module 1, with the openings 13a, 13 a' exposing the mounting portion of the IC chip 14, so that the insulating substrate 11 around the periphery of the IC chip 14 is reinforced without increasing the height of the IC module. Thus, the reinforcing sheet 16 is hardly deformed by the curing shrinkage of the sealing resin covering the IC chip 14. In other words, at the time of hot pressing, in the lamination of the thermoplastic resin sheets 21, 21', even if the sealing resin 15 is subjected to a temperature higher than its glass transition temperature, the reinforcing sheet 16 is hardly deformed. Therefore, flatness of the surface including the IC chip mounting portion in the card substrate 2 sealing the IC module 1 can be ensured.

In this way, when the IC chip 14 is protected with the reinforcing sheet 16 provided on the chip, the surface flatness of the reversible recording layer 3 provided on the card substrate 2 is improved. As a result, in such a card with improved reliability, when a printing operation is performed on the reversible recording layer 3, the gap between the reversible recording layer 3 and the print head is reduced, so that printing can be reliably performed, improving the printing performance of the reversible recording layer 3.

The IC card structure in the present invention is not limited to the structure in which the IC chip 14 and the circuit pattern 12 are all provided on the same insulating substrate 11 as shown in fig. 1, but may be, for example, the structure shown in fig. 9 in which the insulating substrate 11 provided with the IC chip 14 and the insulating substrate 11 'provided with the circuit pattern 12 constituting an antenna or the like are provided, respectively, and the circuit pattern 12 on the insulating substrate 11 connected to the IC chip 14 is connected to the circuit pattern 12 on the insulating substrate 11' by wire bonding or the like. Alternatively, although not shown, there may be a structure in which the insulating substrate 11 has a conductive material (e.g., an antenna coil) extending therefrom. Further, in the above structure, the reversible recording layer may be provided on the non-mounting surface of the IC chip, and the same effect can be obtained.

In the above-described embodiment, the structure of the card base 2 having two thermoplastic resin sheets subjected to hot pressing is explained, but the IC card in the present invention is not limited to one using the card base 2 having the above structure, and an IC card having a card base with, for example, two outer sheets with an adhesive resin filled therebetween may be used, and the same effects can be obtained. In this case, the IC module is sealed between the two outer sheets by an adhesive resin.

Examples of the invention

Specific examples 1 to 19 of the present invention and comparative examples 1 to 8 of these examples and evaluation results thereof will be described below. Here, the evaluation samples (specifically, the IC cards in examples 1 to 19 and comparative examples 1 to 8) were expressed by the shapes and structures of the reinforcing film patterns 13, 13' shown in table 1 below as elements, and evaluation was made with respect to the reversible recording layer 3, the communication characteristics, and the static load strength of each of the evaluation samples.

	Reinforced film layer			Reinforcing sheet on IC non-mounting surface	Evaluation of
									On the IC mounting surface	On IC non-mounting surface	Reinforcing film layer portion on non-mounting surface of IC stacked on circuit pattern	Printing performance	Communication characteristics (mm)	IC strength (kgf)
Example 1	Is provided with	-	-		-	△	93								8.2
				Example 2				Is provided with	Is provided with	Is provided with	-	○	88	7.7
Example 3	-	Is provided with	Is provided with		-	△	88								8.6
				Example 4				With (larger than strengthening thin slice size)	-	-	-	○	92	8.2
Example 5	With (larger than strengthening thin slice size)	With (larger than strengthening thin slice size)	Is provided with		-	○	87								8.4
				Example 6				-	With (larger than strengthening thin slice size)	Is provided with	-	○	88	8.8
Example 7	Is provided with	Is provided with	Is not provided with		-	○	92								8.3
				Example 8				-	Is provided with	Is not provided with	-	△	93	8.7
				Example 9				Is provided with	-	-	Is provided with	△	93	12.3
Example 10	Is provided with	Is provided with	Is provided with		Is provided with	○	86								12.6
				Example 11				-	Is provided with	Is provided with	Is provided with	△	87	12.8
Example 12	With (larger than strengthening thin slice size)	-	-		Is provided with	○	93								12.6
				Example 13				With (greater than reinforced sheet ruler)	With (greater than reinforced sheet ruler)	Is provided with	Is provided with	○	87	12.2

	Inch)	Inch)
								Example 14	-	With (larger than strengthening thin slice size)	Is provided with	Is provided with	○	88	12.7
Example 15	Is provided with	Is provided with	Is not provided with	Is provided with	○	93	13.1
								Example 16	-	Is provided with	Is not provided with	Is provided with	△	93	12
								Example 17	-	Comprising (the larger part is superposed on the circuit pattern)	Is provided with	-	○	70	7.8
Example 18	With (larger than strengthening thin slice size)	With (larger than strengthening thin slice size)	Is provided with	Is provided with	○	93	12.6
								Example 19	-	With (larger than strengthening thin slice size)	Is provided with	Is provided with	○	93	12.5
								Comparative example 1	-	-	-	-	×	93	8.3
Comparative example 2	-	-	-	Is provided with	×	94	12.5
								Comparative example 3	With (without opening)	-	-	-	×	87	8
Comparative example 4	With (without opening)	With (without opening)	Is provided with	-	×	85	9.1
								Comparative example 5	-	With (without opening)	Is provided with	-	×	87	8.4
Comparative example 6	With (without opening)	-	-	Is provided with	×	88	12.9

Comparative example 7	With (without opening)	With (without opening)	Is provided with	Is provided with	×	85	13
								Comparative example 8	-	With (without opening)	Is provided with	Is provided with	×	87	12.6

Examples 1 to 8

In examples 1 to 8, IC cards were produced separately from IC modules having a structure in which the reinforcing sheet 16 was provided only on the IC mounting surface as shown in fig. 2. The IC chip 14 provided in the IC card of each example has a 4rnm × 4mm planar pattern, and a circular reinforcing sheet 16 having a diameter of 7mm is overlaid on the IC chip 14 with their centers aligned with each other. Further, in the IC card of each of examples 1 to 8, reinforcing film patterns 13, 13' of shapes to be described below are provided, respectively.

Example 1

In the IC card of example 1, the IC module 1 shown in the plan view of fig. 10 (this applies to the subsequent view as well as from the top of the reinforcing sheet 16) is used, in which the reinforcing film pattern 13 is provided only on the IC mounting surface. The reinforcing film pattern 13 is a square having one side with a length 0.5mm shorter than the diameter of the reinforcing sheet 16, i.e., a square having an outer periphery of 6.5mm × 6.5 mm. In the reinforcing thin film pattern 13, the opening 13a is square, and the length of one side thereof is 0.3mm longer than the side length of the square IC chip 14, that is, the opening 13a is square 4.3mm × 4.3 mm. The outer sides of the reinforcing film patterns 13 are parallel to the corresponding sides of the openings 13a, respectively. Further, the reinforcing film pattern 13 can be obtained by patterning in the same conductive film as that for the circuit pattern 12, and therefore the bypass pattern 13b is formed in the reinforcing film pattern 13 at the junction of the circuit pattern 12 and the IC chip 14, so that the reinforcing film pattern 13 is reliably insulated from the circuit pattern 12. The width of the bypass pattern 13b is 0.3mm larger than the width of the circuit pattern 12.

The reinforcing film pattern 13, the IC chip 14, and the reinforcing sheet 16 having the shape are arranged such that the IC chip 14 is mounted in the opening 13a of the reinforcing film pattern 13 in a non-contact manner with their centers aligned with each other. Thus, when viewed from the top of the reinforcing sheet 16, the four corners of the reinforcing film pattern 13 "protrude" from the reinforcing sheet 16.

Example 2

In the IC card of example 2, an IC module shown in fig. 11 was used, in which reinforcing film patterns 13, 13' were provided on the IC mounting surface and the non-mounting surface, respectively. The shape and structure of the reinforcing film pattern 13 and the reinforcing sheet 16 on the mounting surface of the IC chip 14 are the same as those in example 1. The reinforcing film pattern 13 'on the non-mounting surface has the same outer peripheral shape as the reinforcing film pattern 13 on the mounting surface and has an opening 13 a'. The bypass pattern is not formed on the portion of the reinforcing thin film pattern 13 'where the circuit pattern 12 is formed, and only the square opening 13 a' is formed in the center of the square pattern in the same direction.

The reinforcing film pattern 13, the IC chip 14, the reinforcing sheet 16, and the reinforcing film pattern 13 'having the above-described shapes are arranged such that the IC chip 14 is disposed in the reinforcing film pattern 13 in a non-contact manner, the reinforcing film pattern 13 and the reinforcing film pattern 13' are arranged in the same direction with their centers aligned with each other. The reinforcing film pattern 13' is shown displaced in this figure for the sake of illustration. In this structure, the four corners of the reinforcing film patterns 13, 13' are "protruded" from the reinforcing sheet 16 when viewed from the top of the reinforcing pattern 16. Further, the portion of the circuit pattern 12 connected to the IC chip 14 is superposed on the reinforcing film pattern 13' on the non-mounting surface.

Example 3

In the IC card of example 3, an IC module as shown in fig. 12 was used in which a reinforcing film pattern 13' was provided only on the non-mounting surface of the IC chip 14. The structures of the IC chip 14, the reinforcing sheet 16, and the reinforcing film pattern 13' are the same as in example 2.

Example 4

In the IC card of example 4, an IC module shown in fig. 13 was used in which a reinforcing film pattern 13 was provided only on the IC mounting surface. In example 4, the outer peripheral shape of the reinforcing film pattern 13 was an enlarged version of the reinforcing film pattern in example 1 described with reference to fig. 10, and the other structure was the same as that in example 2. Specifically, the reinforcing film pattern 13 is a rectangle having one side 2mm longer than the diameter of the reinforcing sheet 16, that is, a rectangle of 9mm × 9 mm. Thus, the outer periphery of the entire reinforcing film pattern 13 "bulges" out of the reinforcing sheet 16 when viewed from the top of the reinforcing sheet 16.

Example 5

In the IC card of example 5, an IC module shown in fig. 14 was used, in which a reinforcing film pattern 13 and a reinforcing film pattern 13' were provided on an IC mounting surface and a non-mounting surface, respectively. In example 5, the outer peripheral shape of the reinforcing film patterns 13, 13' was an enlarged version of the corresponding member in example 2 described with reference to fig. 11, while the other structure was the same as in example 2. That is, the outer peripheral shape of the reinforcing film patterns 13, 13' is the same as that of the reinforcing film pattern 13 in example 4.

Example 6

In the IC card of example 6, an IC module shown in fig. 15 was used in which a reinforcing film pattern 13' was provided only on the non-mounting surface of the IC chip 14. The structure of the IC chip 14, the reinforcing pattern 16, and the reinforcing thin film pattern 13' are the same as those in example 5.

Example 7

In the IC card of example 7, an IC module shown in fig. 16 was used, in which reinforcing film patterns 13, 13' were provided on the IC mounting surface and the non-mounting surface, respectively. In example 7, a bypass pattern 13b 'was provided in a portion where the circuit pattern 12 was formed in the reinforcing film pattern 13' in example 2 described with reference to fig. 11, and the other structure was the same as in example 2. Therefore, the circuit pattern 12 connected to the IC chip is not covered on the reinforcing film pattern 13' on the non-mounting surface. The width of the bypass pattern 13b is 0.3mm wider than the width of the circuit pattern 12.

Example 8

In the IC card of example 8, an IC module shown in fig. 17 was used in which a reinforcing film pattern 13' was provided only on the non-mounting surface of the IC chip 14. The IC chip 14, the reinforcing sheet 16, and the reinforcing film pattern 13' are the same as those in example 7.

Examples 9 to 16

In examples 9 to 16, there are respectively presented IC cards having IC modules adopting the structure shown in fig. 8, in which reinforcing sheets 16, 16' are respectively provided on the IC mounting face and the back face. The differences between examples 9 to 16 and the corresponding portions of examples 1 to 9 are: on the non-mounting surface, a reinforcing pattern 16' is also provided, and the other structures are the same. Specifically, in the IC card of each example, the IC chip 14 and the reinforcing sheet 16 were arranged in the same manner as in examples 1 to 8, and further, the reinforcing sheet 16' had the same shape as the reinforcing pattern 16, so that the center thereof was aligned with the center of the reinforcing sheet 16. Further, in the IC cards of examples 9 to 16, reinforcing film patterns 13, 13' having the same shape as in examples 1 to 8 were provided. The correspondence between the examples and the figures is referenced as follows:

example 9- -example 1 (FIG. 10)

Example 10- -example 2 (FIG. 11)

Example 11- -example 3 (FIG. 12)

Example 12- -example 4 (FIG. 13)

Example 13- -example 5 (FIG. 14)

Example 14- -example 6 (FIG. 15)

Example 15- -example 7 (FIG. 16)

Example 16- -example 8 (FIG. 17)

Example 17

In example 17, as shown in fig. 18, an IC card is presented which is the same as the IC card employing the IC module of the structure shown in fig. 2 except that the reinforcing thin film pattern 13 'having a relatively large area is provided only on the IC non-mounting surface so that the reinforcing thin film pattern 13' is overlaid on a portion of about 1/3 of the circuit pattern 12 on the IC mounting surface, wherein the reinforcing sheet 16 is provided only on the IC mounting surface. The size of the reinforcing film pattern 13' is about 1/3 the size of the insulating substrate 11.

Examples 18 and 19

In these examples, the same IC cards as those in examples 13 and 14 described with reference to fig. 14 and 15 were respectively presented except that the reinforcing film pattern 13' on the non-mounting surface in the IC module used was divided into a plurality of portions. In these embodiments, as shown in fig. 19 and 20, the reinforcing film pattern 13' on the non-mounting surface is divided into two parts, i.e., one part is overlaid on the input portion of the circuit pattern 12 connected to the IC chip 14 and one part is overlaid on the output portion of the circuit pattern 12. The correspondence between examples 18 and 19 and examples 13 and 14 and the drawings is referred to as follows:

example 18- -example 13 (FIG. 19)

EXAMPLE 19- -example 14 (FIG. 20)

Comparative examples 1 and 2

In comparative examples 1 and 2, IC cards having conventional structures are presented, respectively, in which IC modules without the reinforcing film patterns 13, 13' are employed. Specifically, in comparative example 1, the reinforcing sheet 16 of the presented IC card is provided only on the IC mounting surface, and in comparative example 2, the reinforcing sheets 16, 16' of the presented IC card are provided on the IC mounting surface and the non-mounting surface, respectively.

Comparative examples 3 to 5

In comparative examples 3 to 5, IC cards employing IC modules having the structure shown in fig. 2 are respectively presented in which the reinforcing sheet 16 is provided only on the IC mounting surface. Note that, as shown in fig. 21 to 23, in the IC card of each comparative example, the reinforcing film patterns 103, 103' are not provided with openings in the IC chip mounting portion. Further, in comparative examples 3 to 5, the outer peripheral shape and structure of the reinforcing film patterns 103, 103' correspond to those of examples 1 to 3. The correspondence between examples 1 to 3 and comparative examples 3 to 5 and the drawings is referred to as follows:

COMPARATIVE EXAMPLE 3- - - - - -EXAMPLE 1 (FIG. 21)

COMPARATIVE EXAMPLE 4- -EXAMPLE 2 (FIG. 22)

COMPARATIVE EXAMPLE 5- -EXAMPLE 3 (FIG. 23)

Comparative examples 6 to 8

Comparative examples 6 to 8 are examples of IC cards having the structure shown in fig. 8, in which the reinforcing sheets 16, 16 'are provided on the IC mounting surface and the non-mounting surface, respectively, and the reinforcing film patterns 103, 103' in the IC module employed are not provided with openings in the IC chip mounting portion. The shapes and structures of the outer peripheries of the reinforcing film patterns 103, 103' in each of comparative examples 6 to 8 correspond to those of examples 1 to 3. The correspondence between examples 1 to 3 and comparative examples 6 to 8 and the drawings is referred to as follows:

COMPARATIVE EXAMPLE 6- - - - - -EXAMPLE 1 (FIG. 21)

COMPARATIVE EXAMPLE 7- -EXAMPLE 2 (FIG. 22)

COMPARATIVE EXAMPLE 8- - - - - -EXAMPLE 3 (FIG. 23)

The IC card in each of comparative examples 3, 4, 6 and 8, in which the reinforcing thin film pattern 103 is provided on the IC mounting surface, the reinforcing pattern 103 is provided so as to be integrated with the support pattern 18 for supporting the IC chip 14. (see FIG. 2)

Next, the procedure for producing the IC cards in the examples and comparative examples will be described:

the method comprises the following steps: first, the manufacturing method of the IC module is as follows:

an aluminum foil (20 μm) was applied on an IC mounting surface of an insulating base 11 (thickness 50 μm) composed of polyethylene terephthalate so as to form a resist pattern on the aluminum foil. Then, the aluminum foil is etched using the resist pattern as a mask to form a circuit pattern 12 composed of the aluminum foil on the ethylene terephthalate, and a reinforcing film pattern 13 and a support pattern 18 for the IC chip 14 which are not in contact with the circuit pattern 12. The reinforcing thin film pattern 103 was formed in the comparative example. When the reinforcing thin film pattern 13 ' is formed on the IC non-mounting surface, the reinforcing thin film pattern 13 ' composed of aluminum foils (reinforcing thin film patterns 103 ') having respective shapes is formed by the same process. Thus, an antenna module (flexible printed circuit board) having a circuit pattern (12) formed on an insulating substrate 11 was prepared.

An IC chip 14 (length: 4mm × width: 4mm × thickness: 180 μm)14 is bonded face down on the antenna module via an anisotropic conductive adhesive layer 17, the IC chip 14 is sealed with an epoxy sealing resin 15, and a reinforcing sheet 16 is placed on the resin. Then, the sealing resin 15 is cured at 100 ℃. On the other hand, when the reinforcing sheet 16 'is provided on the IC non-mounting surface, the reinforcing sheet 16' is provided on the non-mounting surface of the insulating substrate 11 through the sealing resin 15 ', and then the sealing resin 15' is cured at 100 ℃. Thus, the IC module 1 is produced. As the reinforcing sheets 16, 16', sheets obtained by a forming process specified in JIS of SUS304H were used so that sheets having a thickness of 50 μm could be used.

Secondly, the card substrate is produced according to the following procedures:

front and rear thermoplastic sheets (thickness 280 μm)21, 21' were prepared, consisting of PET-G (copolymer of terephthalic acid, cyclohexanedimethanol ester and ethylene glycol) mixed with a white filler (titanium dioxide). The previously prepared IC module 1 is placed between the thermoplastic sheets 21, 21 ', and the four corners of the thermoplastic sheets 21, 21' are melted by the ultrasonic welding machine to temporarily fix them together. Then, oriented polypropylene (OPP) film sheets were placed on both sides of the temporarily fixed sheet, and they were placed together between stainless steel lenses (thickness 3mm) at a temperature of 170 ℃ and a pressing pressure of 15kg/cm²Under conditions of melting them by hot melt pressure, then cooling to solidify, and peeling off the OPP sheet, thereby obtaining a card substrate 2 in which the IC module 1 is sealed inside.

Thirdly, the manufacturing process of the printed sheet is as follows:

on a sheet (thickness 100 μm) made of polyethylene terephthalate, patterns were printed on the front and back surfaces of the sheet by screen printing/offset printing, respectively, and an adhesive coating composition (shown below) was applied to the back surface of each of the sheets by a gravure printing method so that the thickness of the applied composition was 3 μm, and then dried at a drying temperature of 100 ℃, thereby preparing a sheet for the front surface and a sheet for the back surface.

The formula of the adhesive layer sizing material is as follows:

40 parts by weight of polyester resin

50 parts by weight of toluene

50 parts by weight of methyl ethyl ketone

(iv) in addition, a reversible recording sheet was prepared.

A lueco thermal recording sheet (manufactured and sold by MITSUBISHI PAPER MILLS LIMITED; product name: TRF33) was prepared as a reversible recording sheet. The structure of the thermal recording sheet is as follows: a base material composed of polyethylene terephthalate and having a thickness of 25 μm, a recording layer having a thickness of 7 μm, and a protective layer having a thickness of 3 μm for protecting the recording layer were provided on the base material.

After each part is made as described above, the card is made using these parts according to the following procedure.

First, the printed sheet for the front side obtained in the third paragraph is placed on the card substrate 2 made on the thermoplastic sheet 21 side (IC mounting surface side) in the fourth paragraph, and the printed sheet for the back side obtained in the third paragraph is placed on the thermoplastic sheet 21' side (non-mounting surface side). Each sheet is placed with the printing surface on the outside. Then, the reversible recording sheet obtained in (iv) is placed on the sheet for front face with the protective layer facing outward. The resulting laminate was then temporarily fixed by an ultrasonic welding machine. Oriented polypropylene film sheets were placed on both sides of the temporarily fixed sheet, and they were placed together on a stainless steel lens (thickness 3mm)) At a temperature of 120 ℃ and a pressing pressure of 15kg/cm²Under vacuum hot melt pressure, and then cooled to solidify, followed by punching out the card shape, thus producing the IC cards presented in the examples and comparative examples, in which the reversible recording layer 3 was provided on the card substrate 2.

And (3) evaluation:

with the IC cards obtained in examples 1 to 19 and comparative examples 1 to 8 as evaluation samples, the printing performance, communication characteristics and card strength of the reversible recording layer 3 were evaluated as follows. The results of the evaluation are shown in table 1 above.

Printing performance

As for the reversible recording layer 3, printing can be performed using a thermal printer (KMZ) manufactured and sold by Kyushu Matsushita Electric co., ltd. with an energy applied to the thermal head of 0.55 mJ/dot. In the portion of the reversible recording layer 3 on the IC chip mounting portion, if a printing error occurs, the printing performance is rated x; if there was a slight contact of the printed portion, the printing performance was rated as Δ; when there was no printing error, the printing performance was rated as ≈ o.

Communication characteristics

Using the communication distance between the reader/writer and the IC card as an element, the IC card operation was measured by a reader/writer (communication device) manufactured and sold by sony corporation to measure the maximum communication distance, which is the communication characteristic of the IC card.

IC strength

The load (static load strength) applied to the IC chip mounting portion until the IC chip is broken was evaluated. The breakage of the IC chip was evaluated from the point of time at which communication could not be achieved under the condition that the position of the applied load was the center of the mounting portion of the IC chip, the tip of the indenter was a sphere having a radius of 0.2mm, and the speed of the applied load was 0.5 mm/min. In the inspection process of the IC operation, a reader/writer (communication device) used is a product manufactured and sold by Sony Corporation.

As a result of the above evaluation, it was confirmed that in each of the IC cards of examples 1 to 19, i.e., the IC cards having the reinforcing film patterns 13, 13 with the openings in which the IC chip 14 was mounted, the printing performance for the reversible recording layer 3 was evaluated as Δ or o, which could be maintained in a good condition. Specifically, the reinforcing film patterns 13, 13 in examples 2, 5, 7, 10, 13 and 15 were provided on the IC mounting surface and the non-mounting surface, respectively, and the reinforcing film patterns 13 or 13 in examples 4, 6, 12 and 14 were provided on one surface with sufficient effective dimensions to cover the reinforcing sheets 16, which proved to have very good printing performance and thus ensured no minute contact on the printed portion.

In contrast, in each of the conventional IC cards of comparative examples 1 and 2, in which the reinforcing film pattern was not provided as in the conventional manner, whereas in each of the IC cards of comparative examples 3 to 8, the reinforcing film patterns 103, 103 were provided without the opening having the IC chip mounted therein, there was a printing error (printing property:. times.) and the printing property could not be maintained in a good state.

Further, of examples 1 to 19, in examples 1, 4, 9 and 12 in which the reinforcing film pattern was not provided on the non-mounting surface and the reinforcing film pattern did not cover the portion on the circuit pattern 12, and in examples 7, 8, 15 and 16 in which the reinforcing film pattern 13 was provided on the non-mounting surface but the portion on the circuit pattern 12 was not covered by the reinforcing film pattern 13, it was confirmed that this structure can ensure the same communication characteristics as those obtained in comparative examples 1 and 2 as the conventional art examples. In addition to the above results, in example 17, the portion of the reinforcing film pattern 13 on the non-mounting surface which was overlaid on the circuit pattern 12 was large, and communication characteristics could not be obtained. From these results, it was confirmed that if the reinforcing film pattern 13 on the non-mounting surface is composed of a conductive material, the communication characteristics can be maintained in a good state by reducing the portion of the reinforcing film pattern 13 which is overlaid on the circuit pattern 12.

Further, of examples 1 to 19, in examples 18 and 19, in which the reinforcing film pattern 13 on the non-mounting surface was divided so that each portion was covered on the circuit pattern 12, it was confirmed that this structure can ensure the same communication characteristics as those obtained in comparative examples 1 and 2 as the conventional art examples. From this result, it was confirmed that when the reinforcing film pattern 13 on the non-mounting surface is composed of a conductive material, by dividing the reinforcing film pattern 13' so that each portion covers the circuit pattern 12, good communication characteristics can be maintained.

Further, the reinforcing sheet 16 in examples 1 to 8 is provided only on the mounting surface at the same level of IC strength (static load strength) as that in comparative example 1 in which the reinforcing sheet is provided only on the mounting surface in a similar manner, so that it can be confirmed that the IC strength is not lowered by the provision of the reinforcing film patterns 13, 13 and the protection of the IC chip 14 is maintained by means of the reinforcing sheet 16.

Further, the reinforcing sheets 16, 16 in examples 9 to 16 were provided on the IC mounting surface and the non-mounting surface, respectively, with the IC strength at the same level as the IC strength (static load strength) in comparative example 2 in which the reinforcing sheets were provided on the respective surfaces in a similar manner, so that it was confirmed that the IC strength was not lowered by the provision of the reinforcing film patterns 13, 13 and the protection of the IC chip 14 was maintained by means of the reinforcing sheet 16.

As described above, in the IC card of the present invention, by providing the reinforcing thin film patterns for the IC module on both surfaces of the insulating substrate, it is possible to suppress deformation of the reinforcing sheet provided on the IC chip and to ensure flatness of the surface of the portion including the periphery of the IC chip mounting portion. Therefore, in such an IC card, the IC chip is protected by the reinforcing sheet, thereby improving reliability and improving printing performance of the reversible display layer provided on the surface of the substrate.

Claims (8)

1. An IC card, comprising: an IC module including an IC chip provided on an insulating substrate, a reinforcing sheet provided on the IC chip by a sealing resin sealing the IC chip; a card substrate made of a resin for sealing said IC module; and a reversible display layer disposed on at least one surface of the card substrate, characterized in that:

a reinforcing film pattern having an opening exposing a mounting portion of an IC chip is provided on at least one of the IC chip mounting surface and the non-mounting surface of the insulating substrate.

2. The IC card according to claim 1, characterized in that: the periphery of the opening in the reinforcing film pattern is closer to the IC chip side than the outer periphery of the reinforcing sheet.

3. The IC card according to claim 1, characterized in that: at least a portion of the outer periphery of the reinforcing film pattern is outside the outer periphery of the reinforcing sheet.

4. The IC card according to claim 1, characterized in that: the insulating substrate also has a reinforcing sheet disposed on the non-mounting surface at a corresponding position of the IC mounting portion by an adhesive.

5. The IC card according to claim 1, characterized in that: the insulating substrate has a circuit pattern formed on the mounting surface, and the reinforcing film pattern provided on the mounting surface is composed of the same material as that constituting the circuit pattern.

6. The IC card according to claim 1, characterized in that: the insulating substrate has a circuit pattern formed on the mounting surface of the IC chip, and the reinforcing film pattern provided on the non-mounting surface of the insulating substrate is made of a conductive material and has a shape of a portion not covering the circuit pattern.

7. The IC card of claim 1, wherein: the insulating substrate has a circuit pattern formed on the mounting surface of the IC chip, and the reinforcing film pattern provided on the non-mounting surface of the insulating substrate is made of a conductive material and is divided into a plurality of portions each of which is covered on the circuit pattern.

8. The IC card according to claim 1, characterized in that: the reinforcing film pattern is made of an insulating material.