Method of making IC card

• US 5,735,040 A
• Filed: 09/19/1996
• Issued: 04/07/1998
• Est. Priority Date: 12/26/1991
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Takemura, Seiji, Ochi, Katsunori, Kurisu, Tuguo, Kodai, Syojiro
• Primary Examiner(s): VO, PETER DUNG BA
• Application Number:
  US08/716,540
• Time in Patent Office: 565 Days
• Field of Search: 29/841, 29/837, 29/855, 29/856, 156/291, 156/293, 156/295, 264/272.13, 264/272.14, 264/272.17, 264/272.21, 174/52.3, 235/488, 235/492, 257/679, 257/788, 361/737, 361/764, 437/219
• US Class Current: 29/841
• CPC Class Codes: B29L 2017/006 Memory cards, chip cards
• CPC Class Codes: G06K 19/0702 the arrangement including a battery
• CPC Class Codes: G06K 19/0706 the battery being replaceable
• CPC Class Codes: G06K 19/077 Constructional details, e.g. mounting of circuits in the carrier
• CPC Class Codes: G06K 19/07745 Mounting details of integrated circuit chips
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01M 50/216 adapted for button or coin cells
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 1/183 Components mounted in and supported by recessed areas of the printed circuit board
• CPC Class Codes: H05K 2203/1316 Moulded encapsulation of mounted components
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49139 by inserting component lead or terminal into base aperture
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.
• CPC Class Codes: Y10T 29/49171 with encapsulating

Abstract

A method of producing a thin IC card having a built-in battery includes forming a through-hole including an edge in a circuit board having obverse and reverse main surfaces, a circuit pattern being present on a first of the main surfaces of the circuit board; mounting a functional part on the first of the main surfaces of the circuit board; molding said circuit board and said functional part in a resin with a second main surface of said circuit exposed and forming a battery lodging section in the resin molding defined by the through-hole; and mounting a battery in said battery lodging section and electrically connecting the circuit pattern to the battery.

Claims

1. A method of producing a thin IC card having a built-in battery comprising:

forming a through-hole including an edge, in a circuit board, the circuit board having first and second main surfaces, a circuit pattern being present on the first main surface;

mounting a functional part on the first main surface;

forming a card-shaped section including;

inserting the circuit board with the functional part into a mold, the mold including a first protrusion extending through the through-hole in the circuit board; and

injecting a resin into the mold to form the card-shaped section including a battery lodging section at the through hole, the resin covering the first main surface but not the second main surface; and

mounting a battery in the battery lodging section and electrically connecting the circuit pattern to the battery.

2. The method of producing a thin IC card according to claim 1 comprising:

in forming the card-shaped section, forming a recess in the card-shaped section at the second main surface, adjacent to the through-hole and to the circuit board;

forming at least a pair of battery-connection electrodes in the recess; and

in mounting the battery, connecting the battery-connection electrodes in the recess to respective connection terminals of the battery.

3. The method of producing a thin IC card according to claim 2 wherein forming the recess comprises forming at least one slit in the circuit board adjacent to the through-hole.

4. The method of producing a thin IC card according to claim 1 including:

forming in the circuit board at least a pair of cutouts extending from the first main surface to the second main surface at the edge of the through-hole; and

connecting at least a pair of battery-connection electrodes to the circuit pattern on the first main surface of the circuit board, the battery connection electrodes covering the cutouts, wherein

forming the card-shaped section includes inserting the circuit board including the cutouts and the battery-connection electrodes into the mold, the mold including at least a pair of second protrusions, the second protrusions preventing intrusion of the resin into the cutouts, and

mounting the battery includes inserting a pair of connection terminals of the battery into the cutouts from the second main surface and connecting the connection terminals to the battery-connection electrodes covering the cutouts.

5. The method of producing a IC card according to claim 4 wherein the battery-connection electrodes covering the cutouts are dome-shaped electrodes indented toward the card-shaped section.

6. The method of producing a thin IC card according to claim 1 including:

forming at least a pair of projections of the circuit board extending toward the center of the through-hole; and

attaching at least a pair of battery-connection electrodes to the projections, wherein forming the card-shaped section includes inserting the circuit board into the mold, the first protrusion bending the projections away from the through-hole to form the battery lodging section.

7. The method of producing a thin IC card according to claim 1 comprising, after forming the card-shaped section, placing an unexpanded expandable resin in the battery lodging section and, after mounting the battery, while holding the card between dies, expanding the expandable resin to fill the battery lodging section and to form a flat surface flush with the second surface.

8. The method of producing a thin IC card according to claim 1 including, in forming the card-shaped section, forming a decorative-sheet fitting section having a depth equal to a thickness of a decorative sheet in the card-shaped section, and fitting the decorative sheet into the decorative-sheet fitting section.