JP2001160128A - Method for molding ic card, and ic card - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the destruction of an electronic component by a low pressure molding by providing a nozzle part with a restriction means and controlling the opening to make pressure in a cylinder equal to or more than a fixed level so as not have a pressure below supercritical pressure. SOLUTION: These IC card molding method and device provides the nozzle part 12 with the restriction means 11, control the opening so that the internal pressure of the cylinder 1 can not be equal to or less than the supercritical pressure during injection, and an injection molded layer 106 is formed by controlling the quantity supplied of inert gas 18a in accordance with the rotational speed of a screw 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card molding method and an IC card, and more particularly, to an injection molding layer in which an inert gas such as carbon dioxide gas or nitrogen gas is melted in a supercritical state and injection molded. By obtaining a fine foamed layer, an injection molded layer having high strength is obtained. Also, by dissolving the supercritical gas, the fluidity of the resin is increased, so that low-pressure molding becomes possible, without damaging electronic components such as ICs and coils generated at the time of injection, and for improving moldability. Regarding new improvements.

[0002]

2. Description of the Related Art Conventionally, magnetic recording media such as floppy (registered trademark) disks and cassette tapes have been widely used as external storage devices for computers and the like. A card-shaped or packaged IC card provided with the above semiconductor memory is also being used. On the other hand, in the fields of credit cards, IC cards, cash cards, and the like, IC cards having an IC module equipped with a microprocessor and a semiconductor memory have been developed.

[0003] As a method of manufacturing this type of IC card, a laminating method and a counterbore method are known. The laminating method is a method of manufacturing an IC card by wrapping an IC module and a card material with a laminating film, integrating them by a heating press, and then cutting them into small pieces. The counterbore method is a method of manufacturing an IC card by forming an IC module hole in a card material and fixing the IC module there with an adhesive or the like.

Further, Japanese Patent Application Laid-Open Nos. Hei 3-24000 and Hei 2-160594 are known as documents showing a method of manufacturing an IC card using injection molding. JP-A-3-24000 discloses a method in which a base for fixing an IC module is formed by injection molding, the IC module is mounted and fixed on the base, and then injection-molded again to manufacture an IC card. On the other hand, JP-A-2-16059
In JP-A-4, an IC module is fixed or temporarily attached to a printed sheet with an adhesive, and the IC module is placed at a predetermined position in a molding die, the die is closed, and the molding resin is injected. IC
A method for making a card is disclosed. Further, a method of mixing a chemical foaming agent into a molten resin and performing foam molding is adopted. As a general foam molding, foam molding is performed by mixing an inert gas.

[0005]

The conventional method for molding an IC card has the following problems because it is configured as described above. That is, the lamination method is
Since a large number of processes are required, the yield is poor, and this is not suitable for mass production. Further, the counterbore method has a drawback that strict dimensional accuracy by a lathe or the like is required when machining an IC module hole. Also, JP-A-3-24000
The technique disclosed in Japanese Patent Laid-Open Publication No. H11-150686 has a drawback that the production efficiency is poor because two injection molding steps are required. Furthermore, in the technology disclosed in Japanese Patent Application Laid-Open No. 2-24000, the IC module is simply fixed with an adhesive, so that the internal pressure during the injection molding causes displacement or scattering of the IC module, or There is a drawback that the module itself is damaged. In addition, when a conventional chemical foaming agent is used, the foam cells cannot be miniaturized, and the foam cell diameter is as large as 80 to 150 μm, the strength is reduced, and there are many problems such as breaking of the card. When foam molding is used, the cylinder pressure is reduced during injection because the cylinder pressure has not been controlled, and the injection is already in a foamed state. As in the case of standard molding, the height was increased, and electronic parts such as ICs were sometimes damaged. In addition, since the foam particles are large, there is a problem that the strength is insufficient and the card is damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In particular, injection molding is performed by melting an inert gas such as carbon dioxide gas or nitrogen gas in a supercritical state. By molding to obtain a fine foam layer, an injection molded layer having high strength is obtained. In addition, by dissolving the supercritical gas, the fluidity of the resin increases, so that low-pressure molding becomes possible, without damaging electronic parts such as ICs and coils generated at the time of injection, and improving moldability. It is an object of the present invention to provide an IC card molding method and an IC card.

[0007]

According to the present invention, there is provided an IC card molding method comprising: forming an injection molded layer by injection molding;
In a method of molding an IC card, a card is manufactured by molding the injection molding layer with a resin obtained by dissolving an inert gas such as carbon dioxide gas or nitrogen gas in a thermoplastic resin in a supercritical state. In addition, when the injection layer is formed by dissolving an inert gas in a molten resin and molding by foaming injection from a nozzle portion at the tip of a cylinder with a screw, a squeezing amount of a squeezing means for the nozzle portion is made variable. A method of controlling the supply amount of the inert gas into the cylinder in accordance with the rotational speed of the screw by a flow control valve connected to the cylinder, and detecting the injection pressure of the injection. In this method, the degree of opening of the throttle means is controlled in accordance with the injection pressure, and the pressure in the supercritical pressure state is 7.5 MPa or more. Further, the IC card according to the present invention is an IC card having an injection molded layer formed by injection molding,
The injection molding layer has a configuration formed by molding a resin that is dissolved in a supercritical state in a thermoplastic resin in which an inert gas such as carbon dioxide gas or nitrogen gas is melted, and the molten resin is injected from a nozzle at the tip of a cylinder. In an IC card having an injection molded layer formed by injection molding, the injection molded layer is formed such that an inner pressure of the cylinder is lower than or equal to a supercritical pressure during injection by a squeezing means provided in the nozzle portion. This is a configuration obtained by injection so as not to be disturbed, and a configuration in which the pressure in the supercritical pressure state is 7.5 MPa or more.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
A preferred embodiment of a method for forming a C card and an IC card will be described. The outline of the steps of a molding method as an example of the IC card of the present invention will be described. In FIG. 4, reference numeral 100 denotes a base sheet, which is a plastic film made of white acrylonitrile-styrene. One side of the base sheet 100 functions as a base for printing on a card, and the other side functions as a base for fixing an IC module. Also,
Reference numeral 101 denotes a picture printing layer, which is printed on one side of the base sheet 1 as characters or pictures. Reference numeral 102 denotes a print protection layer, which is a layer for protecting the picture print layer 101 from abrasion and the like. As a material of the print protection layer 102, a transparent polyvinyl chloride resin or the like can be used. The print label A is composed of the base sheet 1, the pattern print layer 101, and the print protection layer 102 described above.

Reference numeral 103 denotes an adhesive layer, which is made of a urethane-based adhesive and is laminated on the entire other surface of the base sheet 1. Reference numeral 104 denotes an IC module in which a microprocessor, a memory, a coiled antenna, and the like are sealed with an epoxy resin, a polypropylene resin, or the like. Then, the IC module 104 is fixed to the non-printing surface of the print label A via the adhesive layer 103. Also, I
The C module 104 is configured to simultaneously perform power supply and data communication with an external device via an antenna.

Reference numeral 105 denotes an IC protection layer, which is provided to prevent the IC module 5 from scattering or displacing due to the injection pressure and to prevent the IC module 104 itself from being damaged. The IC protective layer 105 is provided on the entire surface of the adhesive layer 103 so as to cover the entire IC module 104, and is made of acrylonitrile-butadiene-styrene copolymer resin (hereinafter abbreviated as ABS resin). Film. Further, reference numeral 106 denotes an injection molding layer, whose material is ABS resin. The reason why the material of the injection molding layer 106 and the material of the IC protective layer 105 are the same is that
It is used to make the temperature characteristic of the expansion coefficient the same and prevent the IC card from warping.

Next, referring to FIG. 5, I
An example of the manufacturing process of the C card will be described. In addition, this is an example and can be applied to various known molding methods. First, in a first step S1, a print label A is manufactured. That is, after the pattern printing layer 2 is printed on one side of the base sheet 1 by the offset printing method, the print protection layer 3 is printed thereon by the offset printing method.

In the second step S2, the adhesive layer 4 is provided on the entire non-printing surface of the print label A. When the second step S2 ends, the process proceeds to the third step S3. In the third step S3, the IC module 104 is fixed at a predetermined position on the adhesive layer 103.

In a fourth step S4, the IC module 104
The IC protective layer 1 is formed on the entire surface of the adhesive layer 103 so as to cover the whole.
05 is provided. That is, the ABS resin is dissolved or dispersed in a solvent such as toluene, xylene, etc.
Applying and drying by a roll coating method or the like, the IC protective layer 105
To form

In a fifth step S5, the material obtained in the fourth step S4 is placed in one mold a, the other mold b is closed, and then a resin for injection molding is injected. In this case, the injection molding layer 106 is filled on the IC protection layer 6 with the injection molding resin injected into the space formed by the molds a and b. In another molding method, the injection molding layer 106 may be directly formed on the IC module 104 without using the IC protection layer 105.

Next, an injection molding machine and an injection method for injecting the molten resin into the cavity between the molds a and b will be described. First, a cylinder denoted by reference numeral 1 in FIG. 1 is a cylinder having an overall shape of a longitudinal cylinder and having a heater 1A, and a lumen 2 formed inside the cylinder 1.
, A screw 3 is rotatably disposed by a motor M having a rotation detector E such as an encoder.

The screw 3 has a supply section 7, a first melting section 8, a low-pressure section 9, and a supply section 7 extending from a raw material supply port 5 provided with a hopper 4 to a screw head 6 along the longitudinal direction. Two fusion parts 10 are sequentially formed. At the tip end of the screw head 6, there is provided a nozzle unit 12 having a throttle means 11 comprising a throttle valve or a throttle nozzle and a heater 12A. The aperture means 11 is configured to be able to change the aperture state based on an aperture command 14b from the control unit 14 described later.

The screw head 6 of the cylinder 1
Is provided with an injection pressure sensor 13 for detecting the pressure in the screw head section 6, and the injection pressure 13 a detected by the injection pressure sensor 13 is taken into the control section 14. . The internal pressure 15 a of the pressure sensor 15 provided at a substantially central position of the cylinder 1 is configured to be taken into the control unit 14.

A variable electromagnetic type flow control valve 17 is connected to an injection port 16 provided at a substantially central portion of the cylinder 1. The flow control valve 17 is a liquid or gas such as carbon dioxide gas, nitrogen gas or the like. The opening of the flow control valve 17 is variably controlled by a control signal 14 a from the control unit 14.

The rotation speed V of the screw 3 detected by the rotation detector E provided on the motor M is
And based on the screw rotation speed V, the motor M is controlled by a motor speed command Vcom from the control unit 14.
That is, the rotation speed of the screw 3 is controlled to a required speed.

Next, the case where the injection molding layer 106 is actually formed by injection will be described. First, in the state of FIG. 1, the resin raw material 20 sent from the hopper 4 into the cylinder 1 through the supply port 5 of the cylinder 1 rotates based on a motor speed command Vcom from the control unit 14, 20
Is melted by the heating by the heater 1A and the shear heat insulation by the screw 3 and sent to the downstream side. In this case, the squeezing means 11 of the nozzle portion 12 is held in a closed state, and the screw 3
Is plasticized and accumulated in the inner chamber 1a of the screw head portion 6 on the distal end side.

In the case described above, the control signal 1 from the control unit 14
4a, the inert gas 18a is opened by the injection port 16a.
And the inert gas 18a is mixed into the molten resin. In this case, the inert gas 18a
Since the mixing amount in the molten resin is preferably 5 to 20 W%, as shown in FIG. 2, the control unit 14 calculates according to the screw rotation speed V and controls the level of the control signal 14 a. For example, the opening degree of the flow control valve 17 is controlled by performing control as shown in the step characteristics of FIG.

In order to maintain the supercritical gas, the inert gas injected and mixed into the molten resin is supercritical when the internal pressure 15a in the cylinder 1 falls below a certain level (for example, 7.5 Ma or more). Since this state will not be maintained, maintain this constant level so that the pressure does not fall below the supercritical pressure.
The internal pressure 15a is taken into the control unit 14 and the actuator (not shown) of the throttle unit 11 is controlled by the throttle command 14b so that the nozzle unit 12 can be ejected by touching the touch unit 31 of the mold 30 as shown in FIG. Inject while doing. As described above, by performing the injection while maintaining the supercritical pressure state during the injection, the mold 3
0, it is possible to perform low pressure injection (low pressure molding). For example, injection is performed by insert molding of an IC card (not shown) provided in the cavity 33 as shown in FIGS. When forming the forming layer 106, I
Electronic components such as ICs and coils on the C card can be prevented from being damaged or damaged. In the case described above, the injection pressure 13a at the time of injection is detected by the injection pressure sensor 13 provided in the screw head unit 6, and the opening degree of the throttle means 11 is variably controlled by the throttle command 14b according to the injection pressure 13a. are doing. The operation of moving the cylinder 1 forward and touching the nozzle portion 12 with the touch portion 31 of the mold 30 is not shown, but is performed by a well-known cylinder means for moving a cylinder base (not shown) forward. Is performed. It should be noted that the formation structure of the injection molding layer 106 shown in FIGS. 4 and 5 is merely an example, and it is needless to say that it can be applied to an IC card having another structure not shown.

[0023]

According to the present invention, there is provided an IC card molding method and I according to the present invention.
Since the C card is configured as described above, the following effects can be obtained. That is, at the time of foam molding, the internal pressure in the cylinder is kept at a certain level or more by controlling the opening of the throttle means by feedback control of the injection pressure during injection so that the pressure in the cylinder does not always fall below the supercritical pressure. Since the foaming in the cylinder is controlled, the injection into the mold can be performed at a low pressure, and the electronic components can be prevented from being damaged during insert molding of an IC card or the like. That is, since the resin in which the supercritical gas is melted is injection-molded, the fluidity of the resin is improved (2 to 5 times), the injection pressure is reduced by half, and the cell diameter becomes 10 μm or less. The strength of the product does not decrease,
Eliminates card damage. In addition, since the opening of the flow control valve is controlled in accordance with the screw rotation speed, the amount of inert gas mixed in the molten resin can be controlled within a certain range. It is possible to control the foaming state.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a method and an apparatus for molding an IC card according to the present invention.

FIG. 2 is a characteristic diagram when a flow rate is controlled according to a screw rotation speed in FIG.

FIG. 3 is an enlarged configuration diagram of a nozzle touch state in FIG. 1;

FIG. 4 is a sectional view showing an example of the structure of an IC card according to the present invention.

FIG. 5 is a manufacturing process diagram of the IC card of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 3 Screw 11 Throttling means 12 Nozzle part 13a Injection pressure 18a Inert gas 18 Tank 17 Flow control valve 13 Injection pressure sensor 106 Injection molding layer

Claims (8)

[Claims] 1. An IC card molding method for manufacturing an IC card by forming an injection molding layer (106) by injection molding, wherein the injection molding layer (106) is formed of a non-carbon dioxide gas or a nitrogen gas. An IC card molding method characterized by molding with a resin in which an active gas (18a) is dissolved in a supercritical state in a molten thermoplastic resin. 2. The method according to claim 1, wherein the injection molding layer is formed of an inert gas.
Is dissolved in the molten resin, and the cylinder (1) is
2. The IC card according to claim 1, wherein, when forming by foaming injection from a nozzle portion (12) at the tip of the nozzle, the amount of throttle of the throttle means (11) is variable to the nozzle portion (12). Molding method. 3. An inert gas (18a) into the cylinder (1).
Flow control valve (17) connected to the cylinder (1)
The method according to claim 1, wherein the control is performed in accordance with a rotation speed of the screw (3). 4. An injection pressure (13a) of said injection is detected, and an opening degree of said throttle means (11) is controlled according to the injection pressure (13a). The method for molding an IC card according to any one of the above. 5. The pressure in the supercritical pressure state is 7.5 MPa.
5. The method for forming an IC card according to claim 1, wherein the value is not less than a. 6. An injection molded layer (10) formed by injection molding.
6) In the IC card having the above (6), the injection molded layer (106)
Is an IC card characterized by being formed from a resin obtained by dissolving an inert gas (18a) such as carbon dioxide gas or nitrogen gas in a thermoplastic resin in a supercritical state. 7. An injection molded layer formed by injection molding in which molten resin is injected from a nozzle portion (12) at a tip of a cylinder (1).
In the IC card having (106), the injection molded layer (10
6) is obtained by injecting the molten resin by the throttle means (11) provided in the nozzle portion (12) so that the internal pressure of the cylinder (1) does not become lower than the supercritical pressure during the injection. An IC card characterized in that: 8. The pressure in the supercritical pressure state is 7.5 MPa.
8. I according to claim 6 or 7, characterized in that it is not less than a.
C card.