ANTENNA CIRCUIT CONSTITUENT BODY FOR IC CARD/TAG AND IC CARD

• US 20110036914A1
• Filed: 04/28/2009
• Published: 02/17/2011
• Est. Priority Date: 05/09/2008
• Status: Active Grant

• Current Assignee: Toyo Aluminium Kabushiki Kaisha (Nippon Light Metal Holdings Co., Ltd.)
• Original Assignee: Toyo Aluminium Kabushiki Kaisha (Nippon Light Metal Holdings Co., Ltd.)
• Inventors: Egashira, Kiyoji, Shingu, Akira
• Granted Patent: US 8,297,517 B2
• Time in Patent Office: Days
• US Class Current: 235/492
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H05K 1/162 incorporating printed capacitors
• CPC Class Codes: H05K 1/165 incorporating printed inductors
• CPC Class Codes: H05K 2201/0116 Porous, e.g. foam
• CPC Class Codes: H05K 2201/0355 Metal foils
• CPC Class Codes: H05K 2201/0382 Continuously deformed conductors
• CPC Class Codes: H05K 3/4685 Manufacturing of cross-over conductors

Abstract

Provided are an antenna circuit constituent body for an IC card/tag, which is capable of enhancing a Q value by reducing a permittivity of a resin film of which a base material is made; and an IC card. The antenna circuit constituent body (10) for an IC card/tag comprises: the base material (11) made of the resin film; and circuit pattern layers (131 and 132) each formed on each of both sides of the base material (11) and made of aluminum foil. The circuit pattern layer (131) includes a coiled pattern layer. Parts of the circuit pattern layers (131 and 132), which mutually face each other; and a part of the base material (11), which is interposed between the parts of the circuit pattern layers (131 and 132), constitute a capacitor. The circuit pattern layers (131 and 132) are electrically connected by means of crimping parts (13a and 13b). The base material (11) includes a plurality of void-state-air layers. A relative density of the base material (11) with respect to a density of a resin is less than or equal to 0.9. An average volume of the void-state-air layers is greater than or equal to 2 μm³ and less than or equal to 90 μm³.

Claims

1. An antenna circuit constituent body (10) for an IC card/tag, comprising:

a base material (11) made of a resin film;

a first circuit pattern layer (131) formed on one of surfaces of the base material (11) and made of an electrically conductive body including metal as a main component; and

a second circuit pattern layer (132) formed on the other of the surfaces of the base material (11) and made of an electrically conductive body including metal as a main component, wherein

at least either of the first circuit pattern layer and the second circuit pattern layer (131 and 132) includes a coiled pattern layer,

a part of the first circuit pattern layer (131);

a part of the second circuit pattern layer (132), the part thereof facing the part of the first circuit pattern layer (131) with the base material (11) interposed; and

a part of the base material (11), the part thereof interposed between the parts of the first circuit pattern layer and the second circuit pattern layer (131 and 132) constitute a capacitor,

the first circuit pattern layer (131) and the second circuit pattern layer (132) are electrically connected so as to allow electrical continuity therebetween, and

the base material (11) includes a plurality of void-state-air layers, a relative density of the base material (11) with respect to a density of the resin is less than or equal to 0.9, an average volume of the void-state-air layers is greater than or equal to 2 μ

m³ and less than or equal to 90 μ

m³.

2. The antenna circuit constituent body (10) for an IC card/tag, according to claim 1, wherein the resin film is made of polyethylene terephthalate.

3. The antenna circuit constituent body (10) for an IC card/tag, according to claim 1, wherein the resin film is a biaxially-drawn film.

4. The antenna circuit constituent body (10) for an IC card/tag, according to claim 1, wherein the first circuit pattern layer and the second circuit pattern layer (131 and 132) are made of aluminum foil.

5. The antenna circuit constituent body (10) for an IC card/tag, according to claim 1, wherein each of the first circuit pattern layer and the second circuit pattern layer (131 and 132) and the base material (11) are thermally bonded with each adhesive layer (12) interposed therebetween, respectively.

6. An IC card (100), comprising:

the antenna circuit constituent body (10) for an IC card/tag, according to claim 5; and

cover materials (20) each bonded through thermal compression on each of both sides of the antenna circuit constituent body (10) for an IC card/tag with said each adhesive layer (12) interposed therebetween, respectively.

7. The IC card (100) according to claim 6, wherein a peel strength between the antenna circuit constituent body (10) for an IC card/tag and the cover materials (20) is greater than or equal to 6 N/10 mm.