Mitsubishi Denki Kabushiki Kaisha

Tuguo Kurisu

Katsunori Ochi

Syojiro Kodai

Osamu Murakami

Seiji Takemura

Makoto Kobayashi

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.

Method of making IC card

A thin IC card includes a circuit board on which functional parts are mounted and a through-hole defining an edge of a battery lodging section in which a battery is disposed, the circuit board being embedded in a molding-resin section with the reverse surface of the board exposed. The battery lodging section is aligned with the through-hole of the circuit board. Electrical connections between the circuit board and the battery are effected in a recess or cutouts in the circuit board. The battery is embedded in the lodging section using an expandable resin to make the card surface flat.

Thin IC card

A method for producing an IC card including filling a confined space with a mixture including a foaming resin, the mixture having not been foamed yet, the space being confined by a frame having cut-out portions on inner edges and at least one through-hole passing through the frame in the lateral direction between the inside and the outside of the frame, a circuit board on which functional components are mounted and having edges fitted to one of the cut-out portions of the frame so that the surface of the circuit board on which functional components are mounted faces inward, the frame and the circuit board forming a substantially flat outer surface, and a thin plate having edges fitted to another of the cut-out portions of the frame with the thin plate opposing the circuit board, the frame and the thin plate forming a substantially flat outer surface; foaming the mixture at a predetermined temperature for a predetermined time, thus filling the confined space with foamed resin, and thus making the foamed resin a structural member having mechanical strength, molding the frame, the circuit board, and the thin plate into one body; and removing excess foamed resin from the through-hole in the frame.

An IC card includes: a circuit board on which functional components are mounted; and a frame covered with a thin plate, the circuit board being disposed in the frame, the inside of the frame being filled with a foamed resin. As a result of the above arrangement, an IC card having a strong resistance to various external forces is produced. Furthermore, because it is possible to incorporate a surface material with a design in an integrally molded device, thus it is also possible to produce an IC card device having an excellent appearance.

Growing community of inventors

Sanda, Japan

Tuguo Kurisu