JP5177641B2 - Laminated body and antenna - Google Patents

Description

  The present invention relates to a laminate in which soft magnetic amorphous metal ribbons are used for an antenna magnetic core for a vehicle keyless entry system and the like, and an antenna using the laminate.

Conventionally, an antenna using a ferrite magnetic core has been used as a vehicle-side antenna for RFID used in a vehicle keyless entry system or the like. However, since ferrite is brittle, when it is used inside a member having a relatively high impact, such as a door, it has been provided with a shock absorbing material around the ferrite magnetic core. In order to solve this problem, as disclosed in Patent Document 1, it has been proposed to use an amorphous metal ribbon as a material for the antenna magnetic core, and to laminate the amorphous metal ribbon for use in the magnetic core.
Patent Document 2 discloses that a Co-based amorphous metal ribbon is wound around a plate-like bobbin, and a coil is wound around this to form an antenna core. Thus, it is disclosed that an arbitrary curved surface or thickness can be obtained at the end of the magnetic core, and the directivity of the electric field strength can be reduced in transmission / reception of the antenna magnetic core.

In recent years, RFID antennas on the vehicle side have been installed at multiple locations in each door or room, and the location of the electronic key carried by the driver, that is, which vehicle side antenna the electronic key is closest to is always determined. The system can be confirmed. For this reason, many antenna magnetic cores are required, but the material cost and processing cost of the amorphous metal ribbon magnetic core are higher than that of the ferrite magnetic core, and the spread is not progressing.
However, in an antenna using a ferrite core, since the ferrite core is ceramic, there is a problem in that the strength is reduced when thinned, and there is a limit to downsizing by thinning. Moreover, since it is also ceramics, it cannot be used by being bent, and the space in which it can be installed is limited. If an antenna magnetic core with laminated amorphous metal ribbons is applied, the impact resistance can be improved and it can be installed in a narrow space. For example, Patent Document 3 discloses an antenna in which Co-based amorphous metal ribbons are stacked.

Patent Documents 4 and 5 describe a method for producing an amorphous metal ribbon laminate.
In Patent Document 4, after manufacturing a laminate of metal ribbons, heat treatment is performed to optimize the magnetic properties, and then an epoxy resin is impregnated between the layers of the metal ribbon, and the resin is heated and cured to obtain a laminate. Examples of making are described. Also described is a method of cutting a continuous Fe-based amorphous metal ribbon with a predetermined width, heat-treating in the same manner as described above, applying an epoxy resin, laminating each amorphous metal ribbon, and curing the resin by heating. Has been.
In Patent Document 5, a polyimide resin that is extremely excellent in heat resistance is continuously applied and dried on a metal ribbon. After obtaining a predetermined shape by press punching or the like, thermocompression bonding is performed to obtain further magnetic properties. It is described that heat treatment is performed. Compared with the production method using the epoxy resin, by continuously applying and drying, a thin strip punched into a predetermined shape is thermocompressed to produce a laminate, which has high productivity and excellent mass productivity. Can be obtained. The reason for adopting the polyimide resin is that the heat treatment temperature for maximizing the magnetic properties of the amorphous metal material depends on the material composition, but if it is high, it is a region that exceeds 400 ° C. This is because it is a stable resin. However, commercially available polyimide resin liquids are orders of magnitude more expensive than other resin liquids.

JP-A-5-267922 JP 2004-166071 A JP 2007-119922 A Japanese Patent Laid-Open No. 7-278763 Japanese Unexamined Patent Publication No. WO2003 / 060175

  This inventor produced the laminated body using the amorphous metal ribbon with the said manufacturing method. It was found that the adhesive strength between the amorphous metal ribbons was very small in both cases of epoxy resin and polyimide resin. For example, when the peeled portion is formed with a cutter knife at the end of the outermost adhesive layer of the laminate, the peel strength is fixed to a pulling jig, and the peel strength is measured, the adhesive strength is only 5 g / mm or less. I can't get it. Further, when a force for bending the laminate was applied, a phenomenon of peeling from the end portion was observed.

  As described above, the epoxy resin and the polyimide resin have a problem in that the adhesive strength between the ribbons is low and the strips are easily peeled off. In response to these problems, the present inventor has studied a resin having a relatively low cost and a high adhesive strength, a laminate using an amorphous metal ribbon that can be produced at a low cost and has excellent mechanical strength, and the laminate An object of the present invention is to provide an antenna using the antenna.

  As a result of various investigations on a resin that can be applied and dried continuously to an amorphous metal ribbon, such as the polyimide resin, as a bonding resin, the present inventor has used a polyamide-imide resin to obtain a conventional glass. It has been found that a very excellent adhesive force can be obtained by thermocompression bonding at a temperature of 30 ° C. or more and 90 ° C. or less from the glass transition point of the resin as compared with that subjected to thermocompression bonding at a temperature near the transition point. is there.

That is, the present invention is a laminate in which amorphous metal ribbons are thermocompression bonded via a polyamideimide resin, and the thermocompression bonding temperature is 30 ° C. or more and 90 ° C. or less of the glass transition point of the polyamideimide resin. It is characterized by being.
In this laminated body, the amorphous metal ribbon may be an Fe-based amorphous metal ribbon with Fe of 50 atomic% or more. Further, since the peel strength between the amorphous metal ribbons is 15 g / mm or more and strong against peeling, the amorphous metal ribbon can be bent in a range of curvature radius of 100 mm or more and 200 mm or less.
By using these laminates as RFID antenna magnetic cores or antennas, it is possible to provide a bending-friendly one that can be easily mounted in a narrow container.
In addition, the glass transition point of this invention description was calculated | required from the inflection point of the endothermic peak which shows the glass transition measured with the differential scanning calorimeter (DSC).

  According to the present invention, using a relatively inexpensive material, a laminate having excellent mechanical strength and firmly bonding amorphous metal ribbons, and an RFID antenna core and antenna using the laminate are manufactured. be able to. Therefore, compared with a ferrite magnetic core, it is small and light, has excellent impact resistance, and can be used in a bent state.

The present invention is a laminate in which Fe-based amorphous metal ribbons having Fe of 50 atomic% or more are thermocompression bonded via a polyamideimide resin, and the thermocompression bonding temperature is a glass transition point of the polyamideimide resin. It is a laminated body characterized by being 30 ° C. or higher and 90 ° C. or lower. Further, the laminated body is characterized in that the thickness of the polyamideimide resin obtained by thermocompression bonding of the amorphous metal ribbons is 4 to 16% with respect to the metal ribbon thickness. Furthermore, it is an RFID antenna using these laminates.

In addition to the epoxy resin, polyimide resin, and polyamideimide resin, the present inventor added a polyamide resin and a polysulfone resin, and used them as adhesives for the metal ribbons. Went.
As an examination method, 20 layers of metal thin bodies having a width of 5 mm and a length of 50 mm were laminated, and thermocompression bonded by holding at a temperature 10 ° C. higher than the glass transition point of each resin and a pressure of 50 MPa for 10 minutes. Then, after cooling to room temperature, a cutter knife is inserted into the end of the uppermost layer of the laminate to form a peeling part of about 3 mm, and the end 1 mm of this peeling part is fixed to a pulling jig, The peel test was conducted under the condition of pulling at a speed of 10 mm / min. As a result, only the polyamideimide resin exceeded the peel strength of 5 g / mm. Furthermore, detailed examination was performed about the polyamide-imide resin. Here, although the reason why only the polyamide-imide resin has obtained a good result is unknown, as will be described later, the polyamide-imide resin has good wettability with respect to the surface of the metal ribbon. The polyimide resin using the above solvent is accompanied by a change in the skeleton of the resin from the polyamic acid by heat treatment such as drying, that is, imidation reaction, whereas the polyamideimide resin is a polyamideimide resin from the beginning and there is no skeleton change. I guess is related.
Polyamideimide resin is a resin having an amideimide structure as a skeleton of its molecular structure, and various structures other than the skeleton structure can be added. It is also possible to change the average molecular weight and molecular weight distribution. Accordingly, the physical properties of heat resistance, glass transition point, resin flexibility, etc. are somewhat different due to these factors.

As the solvent, a solution dissolved in a mixed solvent of NMP (N-methylpyrrolidone) and xylene can be used. NMP alone or DMAc (N, N-dimethylacetamide) or the like may be used. NMP and DMAc have good wettability with the surface of the metal ribbon, have good adhesion, and can form a coating film having no defects.
The thickness of the resin after coating and drying can be obtained by adjusting the mixing ratio of the resin and the solvent, that is, by adjusting the solid content ratio of the resin.
As the coating apparatus, a gravure roll system having a drying furnace that can be applied to a continuous amorphous metal ribbon at high speed and can be dried immediately after coating is preferable.
The ratio of the thickness of the polyamide-imide resin adhering adjacent metal ribbons is preferably 4% or more and 20% or less with respect to the thickness of the metal ribbon. When the resin thickness ratio is less than 4% of the thickness of the metal ribbon, it is empirically impossible to stably secure the adhesive force between the metal ribbons on the entire bonding surface. In order to ensure the adhesive force more stably, 8% or more is more preferable. However, if it exceeds 20%, the risk of interfacial delamination due to differences in physical properties such as the thermal expansion coefficient of the metal ribbon and resin increases, and the volume ratio of the metal ribbon that determines the characteristics as the antenna core decreases. Not practical.

As will be described later, when the laminate is bent and used, the strain between the metal ribbons adjacent to each other in the stacking direction is large. Therefore, the greater the resin thickness, the more effectively the strain is absorbed. Therefore, when the average radius of curvature is 120 mm or less, the resin thickness is preferably 15% or more of the thickness of the metal ribbon.
Here, the resin thickness is not the thickness after coating and drying, but as will be described later in the examples, the residual solvent is volatilized by heat at the time of thermocompression bonding by hot pressing, and the resin is densified by the effects of temperature and pressure. This is the thickness after heat treatment, that is, the thickness after thermocompression bonding. Moreover, since the resin coating film is formed on both surfaces of the metal ribbon, the resin thickness between the metal ribbons adjacent in the stacking direction is twice the thickness after the thermocompression bonding.
In general, above the glass transition point of the resin, the thermal motion of the alkyl chain or the like bonded to the molecular skeleton structure of the resin becomes intense, and the flexibility and flexibility of the resin are increased. Therefore, it is said that the temperature suitable for thermocompression bonding is close to the glass transition point, preferably slightly higher. If the glass transition point is further exceeded, there is a risk of thermal decomposition of the resin due to the more intense thermal motion, so thermocompression bonding is performed at the minimum necessary temperature, No thermocompression bonding was performed.
However, the inventor has found that in polyamideimide resin, the adhesive strength is low when crimped at a temperature exceeding the glass transition point by 10 ° C., and when it is bent, it is easily peeled off at the interface between the resin and the metal ribbon. Here, it is presumed that the interface between the resin and the resin was more strongly bonded because of the same substance. Therefore, in order to find an appropriate temperature, the examination by the peel test was conducted. As a result, the temperature of the thermocompression bonding was higher than that conventionally considered due to fear of thermal decomposition of the resin, that is, the glass transition point of 30 ° C. As described above, it was found that when the temperature was 90 ° C. or less, the peel strength was 15 g / mm or more, and the peeled portion was not observed even when bent. For stronger bonding, the temperature of thermocompression bonding is preferably 50 ° C. or higher of the glass transition point. If it exceeds 90 ° C. of the glass transition point, it seems to be due to the gas generated by the thermal decomposition of the resin, but “swelling” is observed between adjacent metal ribbons, and a peeled area is generated. If the temperature of thermocompression bonding is 80 ° C. or less of the glass transition point, there is almost no possibility of “blowing” due to pyrolysis gas.

The pressure for thermocompression bonding is preferably 50 MPa or more so that the entire surface of the metal ribbon is sufficiently adhered. Furthermore, 100 MPa or more is more preferable in order to suppress variations among a large number of laminates. The thermocompression bonding is usually performed in a state in which a large number of metal ribbons are aligned in a jig in order to suppress misalignment of the laminated body. For this reason, the press member of the press device is pressured only on the portion that contacts the jig, and therefore, depending on the pressure resistance of the press member, there is a risk that only the contact portion may be deformed. Is preferably 300 MPa or less, more preferably 200 MPa or less.
In addition, since the polyamideimide resin coating film is formed on the surface of the metal ribbon, there is no need to pay particular attention to the oxidation of the Fe-based amorphous metal ribbon surface in the atmosphere of thermocompression bonding, and there is no inconvenience in the air atmosphere. .

The amorphous metal ribbon used preferably has a thickness of 100 μm or less. Since it is thinner than a silicon steel plate, eddy current loss is very small, and it is optimal as a material for obtaining high antenna characteristics with a small volume.
In general, the magnetic properties of Co-based amorphous metal ribbons are optimized by heat treatment exceeding 400 ° C. The polyamideimide resin used in the present invention has a heat-resistant temperature of about 350 ° C., and thus cannot be optimized. On the other hand, the Fe-based amorphous metal ribbon has an optimum heat treatment temperature of about 350 ° C. or less for the magnetic properties, and the magnetic properties can be optimized even if a polyamideimide resin is used.
Accordingly, the Co-based magnetic potential cannot be exhibited because it is lower than the optimized heat treatment temperature. Therefore, even if it is a Fe-type amorphous metal ribbon, the laminated body which has a substantially equivalent magnetic characteristic is obtained. The Fe-based amorphous metal ribbon is much cheaper than the Co-based amorphous metal ribbon. The vehicle-side transmission / reception antenna can be sufficiently put into practical use by optimizing the high-frequency circuit and antenna design.
For these reasons, by using the Fe-based amorphous metal ribbon, a laminate having excellent antenna characteristics, strong peeling strength between the ribbons, and flexibility can be obtained.
The Fe-based amorphous metal ribbon will be described below.
As an Fe-based amorphous metal ribbon, the alloy composition is Fe _a Si _b B _c M _d (where M is one or more elements of Cr, Mo, Mn, Zr, and Hf, and in atomic percent, 50 ≦ a ≦ 90, 5 ≦ b ≦ 30, 2 ≦ c ≦ 15, 0 ≦ d ≦ 10). The amount of Fe is preferably 60% or more and 80% or less in atomic%.
If the Fe amount a is less than 50 atomic% (hereinafter, “%” represents atomic%), the corrosion resistance is lowered, and an antenna core excellent in long-term stability cannot be obtained. On the other hand, if it exceeds 90%, Si and B, which will be described later, are insufficient, and it is industrially difficult to obtain an amorphous metal ribbon. In the range where the Fe amount a is 50 atomic% or more, 10% or less of the Fe amount may be substituted with one or two of Co and Ni. Co and Ni are more preferably 5% or less of the amount of Fe.
The Si amount b is essential as an element contributing to the amorphous forming ability, and is added by 5% or more. However, in order to improve the saturation magnetic flux density, it is necessary to be 30% or less.
The B amount c is essential as an element most contributing to the amorphous forming ability. If it is less than 2%, the thermal stability is lowered, and if it is more than 15%, even if it is added, an improvement effect such as an amorphous forming ability is not seen.
M is an element effective for improving soft magnetic properties. On the other hand, if it exceeds 10%, the saturation magnetic flux density is lowered. Preferably it is 8% or less.
Since C is effective in improving the squareness and saturation magnetic flux density, it may be included as long as it is 3 atomic% or less as a whole. When it exceeds 3 atomic%, embrittlement and thermal stability are deteriorated. Moreover, you may contain 0.50% or less of at least 1 or more types of elements from S, P, Sn, Cu, Al, and Ti as an unavoidable impurity.

When used as an antenna magnetic core, magnetic anisotropy can be imparted in the short side direction of the antenna, in other words, in the width direction or thickness direction. By providing magnetic anisotropy, the antenna characteristic Q is enhanced.
As a method for imparting induced magnetic anisotropy, heat treatment is performed at a Curie temperature or lower while applying a magnetic field. For antennas, for example, a method of heat-treating in a magnetic field at a relatively low temperature of 300 ° C. or lower is preferable because embrittlement does not progress and characteristics are improved. If the relative initial permeability of the material is not so high, there is an effect in improving the Q value of 100 kHz to 150 kHz, and it may be appropriately selected depending on the intended use.
Further, when used as an antenna magnetic core, the metal ribbon preferably has a thickness of 30 μm or less. This is because if it exceeds 30 μm, the Q value is remarkably lowered, the sensitivity as an antenna is lowered, the level of the output signal is lowered, and the like, which is not practical.

In order to install in a limited space, when using the laminate as an antenna core, a hard resin with a recess formed in advance so as to have a predetermined curvature after winding the conductor wire around the antenna core It can be used by fitting it in a case of non-magnetic material such as a product. Or it may be fixed by three or more fixed non-magnetic pins. The larger the refractable curvature is, the more the laminated body can be placed in a narrow space. However, when the function as an antenna and the reliability as a laminated body are taken into consideration, there is a possibility that the average curvature radius is less than 100 mm and the laminated body does not function stably. Considering the stability of the antenna, the average radius of curvature is preferably 120 mm or more. However, if the average radius of curvature exceeds 200 mm, there is almost no merit that it can be installed in a limited space.
It functions as an antenna by winding a conducting wire around the antenna magnetic core. The number of windings and the diameter of the conducting wire are optimized depending on the frequency range to be used, the design specifications of the transmission / reception high-frequency circuit, transmission power, and reception sensitivity.

Hereinafter, the present invention will be described in detail based on examples.
Example 1
As the Fe-based amorphous metal ribbon, 2605SA1 made by Metglas having an average thickness of 25 μm, a width of 170 mm, and a length of 1000 m was used. The Fe-based amorphous metal ribbon was slit into three strips having a width of 50 mm, and each was wound into a paper roll having an inner diameter of 3 inches to form a roll.
As a polyamideimide solution of the adhesive, 3 liters of HPC-5000-30 (glass transition point 270 ° C.) manufactured by Hitachi Chemical Co., Ltd. diluted 1.5 times with a mixed solvent of NMP and xylene were prepared. The solid content ratio after dilution was 20% by weight. Next, the previously prepared polyamideimide solution was poured into the resin liquid reservoir of the gravure roll coating apparatus. Thereafter, the roll-shaped amorphous metal ribbon was set in the gravure roll coating apparatus, and the polyamideimide solution was continuously applied while drawing the amorphous metal ribbon. The gravure roll used was 85 mesh and a depth of 150 μm, and the coating speed was 10 m / min. The roll was rotated at the same peripheral speed as the coating speed with respect to the amorphous metal ribbon, and the polyamideimide solution was transferred and applied.
After the polyamideimide solution was applied, the amorphous metal ribbon was continuously passed through a drying furnace connected to a gravure roll coating apparatus to dry the polyamideimide solution. The drying furnace length was 2 m, and the furnace temperature was 150 ° C. Part of the air inside the furnace is discharged to the outside, and the other internal atmosphere is circulated. The amorphous metal ribbon coated with the polyamideimide solution passed through the drying furnace in about 20 seconds. The amorphous metal ribbon coming out of the drying furnace was not sticky, and it was confirmed that the solvent in the polyamideimide solution was sufficiently dry.
Thus, the polyamideimide solution was continuously applied to an amorphous metal ribbon having a total length of 1000 m and dried. Thereafter, the polyamideimide solution was similarly applied to the opposite surface of the amorphous metal ribbon and dried. When the thickness of the polyamideimide resin after drying was confirmed with a micrometer, the average coating thickness was 4 μm, and the coating thickness variation was within 0.5 μm.

The 50 mm wide amorphous metal ribbon coated and dried with this polyamideimide solution is cut every 5 mm with a cutting machine manufactured by Zoken Co., Ltd., cut into a 50 mm × 5 mm rectangle, and made of stainless steel with a thickness of 2 mm. 20 sheets were stacked on the stacking jig. Prepare an amorphous metal ribbon with polyamideimide resin applied only on one side in the uppermost layer of the laminated amorphous metal ribbon, and do not apply the coated surface to the adjacent amorphous metal ribbon side. The faces were stacked so that they face outward.
Twenty sheets of amorphous metal ribbons were stacked in one layer, and five layers were stacked on the stacking jig.
The stacking jig in which the five layers of the laminate are set is set in a pot press set at a temperature of 300 ° C. (30 ° C. higher than the glass transition point of the resin). After setting, the temperature decreases due to the heat capacity of the stacking jig. After the temperature of the upper and lower presses again became 300 ° C., the pressure was maintained at 50 MPa for 10 minutes. Thereafter, the stacking jig was taken out and cooled to room temperature. From the lamination jig, 5 pressure-bonded laminated bodies were obtained. FIG. 1 shows a schematic diagram of a cross section in the short-side direction of the laminate. 1 is an amorphous metal ribbon, and 2 is a polyamideimide resin. FIG. 2 shows a perspective view of the laminate 3.
When the thickness of 5 pieces was measured, it was about 580 μm, and the thickness of the resin layer between each layer was 4 μm. Thickness after coating: 4 μm × 2 (adjacent metal ribbon single side × 2) = half the value of 8 μm, but by hot press, evaporation of the non-volatile solvent contained in the resin film after coating and drying This is presumably because the resin film was densified by temperature and pressure. In this case, since the thickness of the resin layer sandwiched between the metal ribbons is 4 μm with respect to the metal ribbon thickness of 25 μm, the resin thickness ratio to the metal ribbon thickness is 4/25 = 0.16 = 16. %.
When the appearance of these five laminates was observed with a 10-fold stereo microscope to confirm the presence or absence of swelling, no swelling was observed. Furthermore, when a peel test was conducted, it was confirmed that the peel strength was in a range of 20 to 30 g / mm, and it was firmly adhered.
When the laminate was bent to a radius of curvature of 100 mm with a jig as shown in FIGS. 3 and 4, no peeled portion was observed at the end of the laminate. Further, even after being left for 30 days in a bent state, no peeled portion was observed at the end of the laminate.

(Examples 2 to 4)
Except for the thermocompression bonding temperature, the thermocompression bonding temperature is 320 ° C. (50 ° C. higher than the glass transition point of the resin), 340 ° C. (also 70 ° C. higher), 360 ° C. (also 90 ° C. higher) under the same conditions as in Example 1. A laminate was prepared, and appearance observation and peel strength were measured. The results are shown in Table 1 including Example 1 (Example 1 corresponds to No. 1). In either case, good results have been obtained.
Further, when the laminate after the peel test was bent to a radius of curvature of 100 mm using a jig as shown in FIGS. 3 and 4, no peeled portion was observed at the end of the laminate. Further, even after being left for 30 days in a bent state, no peeled portion was observed at the end of the laminate.

(Comparative Examples 1 and 2)
As a comparative example, when the thermocompression bonding temperature is low: 280 ° C. (10 ° C. higher than the glass transition temperature of the resin) and when the thermocompression bonding temperature is high: 370 ° C. (100 ° C. higher than the glass transition temperature of the resin) These are shown in Nos. 5 and 6 of Table 1, respectively.
When the thermocompression bonding temperature was low, the peel strength was as low as 5 to 10 g / mm. When the laminate after the peel test was bent to a curvature radius of 130 mm, a peeled portion was observed at the end of the laminate.
When the thermocompression bonding temperature was high, swollenness was observed by appearance observation with a stereomicroscope with a magnification of 10 times for all five. It is estimated that the peel strength varies greatly due to this swelling.
Furthermore, as in Examples 1 to 4, after leaving for 30 days in a bent state, when evaluated, a peeled portion was observed at the end of the laminate.

(Comparative Example 3)
As Comparative Example 3, as a polyimide resin, U-Varnish A manufactured by Ube Industries, Ltd. (resin solid content ratio: 18% by weight, glass transition point: 280 ° C.) was used, and the thermocompression bonding temperature was 290 ° C. (from the glass transition point of the resin). Other than that, a laminated body was produced under the same conditions as in Example 1, and the evaluation results are shown in No. 7 of Table 1. The peel strength was a very low result of 3 to 5 g / mm. Although swelling was not recognized, peeling was remarkable.

(Examples 5 and 6)
Of the conditions in Example 1, as shown in Nos. 8 and 9 in Table 2, in order to change the resin thickness, the specifications of the gravure roll and the resin solid content ratio of the polyimide resin solution were changed to produce a laminate. A laminate having a resin thickness ratio of 8% and 4% to the metal ribbon thickness was prepared, and the peel strength was measured. In either case, good results have been obtained.
Further, as in Examples 1 to 4, the film was allowed to stand for 30 days in a bent state and then evaluated, but no peeled portion was observed at the end of the laminate.

(Comparative Examples 4 and 5)
Similarly, as indicated by N10 and 11 in Table 2, a laminate having a resin thickness ratio of 3% and 22% was prepared as a comparative example, and the peel strength was measured.
A 3% laminate had a low peel strength of 5 g / mm. Further, after being allowed to stand for 30 days in a bent state, a peeled portion was observed at the end of the laminate.
The peel strength of the 22% laminate was good, but when observed after standing for 30 days, interfacial peeling was observed.

(Example 7)
As shown in FIG. 5, a 100-turn antenna was produced by winding a conductive wire on the laminate produced under the same conditions as in Example 1, and it was confirmed that the function as an RFID transceiver antenna was satisfied at a frequency of 100 kHz.

(Example 8)
The antenna of Example 5 was bent into a hard resin case having a recess having a curvature radius of 120 mm. Also in this case, the function as an antenna was confirmed.

Example 9
Instead of the Fe-based amorphous metal ribbon of Example 1, a Co-based amorphous metal ribbon was used to produce a laminate under the same conditions. As the Co-based amorphous metal ribbon, an ACO5 material manufactured by Hitachi Metals, Ltd. having an average thickness of 15 μm, a width of 20 mm, and a length of 1000 m was used.
A conductor was wound around the laminate to form a 100-turn antenna, and it was confirmed that it fulfilled the function as a transmission / reception antenna for RFID at a frequency of 100 kHz. In the thermal history in Example 1, the magnetic characteristics of the ACO5 material were not maximized, but the function as an antenna was satisfactory.
However, the material price of the Co-based amorphous metal ribbon was about 100 times as high as that of the Fe-based material.

Laminate cross-sectional schematic diagram of the present invention The perspective view of the laminated body of this invention The figure which shows embodiment of the bent laminated body of this invention The figure which shows other embodiment of the bending laminated body of this invention The perspective view of the antenna of this invention

Explanation of symbols

1 Amorphous metal ribbon 2 Polyamideimide resin 3 Laminate 4 Hard resin case 5 Nonmagnetic pin 6 Conductor

Claims (3)

It is a laminate in which Fe-based amorphous metal ribbons with Fe of 50 atomic% or more are thermocompression bonded via a polyamideimide resin, and the temperature for thermocompression bonding is 30 ° C. or more of the glass transition point of the polyamideimide resin A laminate having a temperature of 90 ° C. or lower. 2. The laminate according to claim 1, wherein a thickness of the polyamideimide resin obtained by thermocompression bonding of the amorphous metal ribbons is 4 to 16% with respect to the metal ribbon thickness . An RFID antenna using the laminate according to claim 1 .

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