Tatsuta Electric Wire & Cable Co., Ltd.

Yuusuke Haruna

Hiroshi Tajima

Takahiko Katsuki

Sougo Ishioka

Yoshihiro Hosoya

Masahiro Watanabe

Kenji Kamino

Yoshihiko Aoyagi

Sirou Yamauchi

Tsuyoshi Hasegawa

Yukari Kobayashi

Kiyoharu Sekiguchi

Shirou Yamauchi

Kenji Aoki

Provided is a conductive adhesive sheet that has excellent connection stability even containing conductive particles in a small proportion. The inventive conductive adhesive sheet contains a binder component and conductive particles. The conductive particles are distributively arranged. Assume that all the conductive particles are regularly arranged; and that an optional region of the conductive adhesive sheet is viewed in plan view so that a distribution number Np of the distributed conductive particles be 9 to 25, a condition: 1.5X≤Y≤100X is met, where X represents the average of equivalent circle diameters of the distributed conductive particles; and Y represents the center-to-center distance between adjacent two of the distributed conductive particles, which are regularly arranged in the plan view. The ratio N/Np is 1.0 to 100.0, where N represents the number of the primary particles in the optional region. When optional three unique regions including the optional region are viewed in plan view so that the distribution number Np in each region be 9 to 25, the ratio Ng/Np is 0.8 to 1.0, where Ng represents the distribution number of conductive particles present in two or more of the three regions.

Conductive adhesive sheet

A shielded printed wiring board with electromagnetic wave shielding film on both sides thereof is produced by placing electromagnetic wave shielding films on the two sides of the printed wiring board, with ends thereof protruding past an end of the printed wiring board. The protruding ends of the electromagnetic wave shielding films are brought together, with an air gap therebetween, and an initial application of heat and pressure causes the ends of the electromagnetic wave shielding film to adhere to each other, but without completely curing adhesive resin components of the electromagnetic wave shielding films. Protective film layers are removed from the electromagnetic wave shielding films, followed by subsequent application of heat and pressure to complete cure of the adhesive resin and to remove the air gap.

Method for manufacturing shielded printed wiring board and shielded printed wiring board

A shielded printed wiring board with a ground member wherein even though a thermal load is applied, the connection stability between the electroconductive particles of a ground member and the shielding layer of a shielding film is hardly deteriorated is provided. A shielded printed wiring board with a ground member of the present invention is a shielded printed wiring board with a ground member, including: a substrate film formed by sequentially stacking a base film, a printed circuit including a ground circuit, and an insulating film; a shielding film including a shielding layer and a protective layer laminated on the shielding layer, the shielding film covering the substrate film such that the shielding layer is closer to the substrate film than the protective layer is; and a ground member arranged on the protective layer of the shielding film, the ground member including an external connection member having a first main surface and a second main surface opposite to the first main surface, and having electroconductivity, electroconductive particles disposed on the first main surface side, and an adhesive resin for fixing the electroconductive particles to the first main surface, wherein circularity of the cross sections of the electroconductive particles in the cross section of the ground member is 0.35 or more, and the electroconductive particles are penetrating the protective layer of the shielding film and connected to the shielding layer of the shielding film, and the external connection member of the ground member is electrically connectable to an external ground.

Shield printed wiring board with ground member and ground member

A shielded printed wiring board includes a substrate film including a base film and printed circuits including a ground circuit formed on the base film; an electromagnetic wave shielding film including a shielding layer and an insulating layer; and a reinforcing member including a conductive adhesive layer and a metal reinforcing plate, wherein the ground circuit of the substrate film is sufficiently electrically connected to the metal reinforcing plate of the reinforcing member. The shielded printed wiring board of the present invention includes a substrate film including a base film and printed circuits including a ground circuit formed on the base film; an electromagnetic wave shielding film including a shielding layer and an insulating layer; a connecting member including a metal foil and a conductive filler fixed to the metal foil with an adhesive resin; and a reinforcing member including a conductive adhesive layer and a metal reinforcing plate, wherein the electromagnetic wave shielding film is arranged on the substrate film in such a manner that the insulating layer of the electromagnetic wave shielding film is located on the shielding layer of the electromagnetic wave shielding film, the connecting member is arranged on the electromagnetic wave shielding film in such a manner that the conductive filler of the connecting member penetrates the insulating layer of the electromagnetic wave shielding film and that the conductive filler of the connecting member is in contact with the shielding layer of the electromagnetic wave shielding film, the reinforcing member is arranged on the electromagnetic wave shielding film and the connecting member in such a manner that the conductive adhesive layer of the reinforcing member is in contact with the insulating layer of the electromagnetic wave shielding film and the metal foil of the connecting member, and the ground circuit of the substrate film is electrically connected to the metal reinforcing plate of the reinforcing member.

Shielded printed wiring board, method for manufacturing shielded printed wiring board, and connecting member

Provided is an electromagnetic wave shielding film capable of easily exhibiting excellent conductivity between a ground member and a shielding layer when the ground member is disposed on the electromagnetic wave shielding film. In the electromagnetic wave shielding film, the conductive adhesive layer, the shielding layer, and the insulating layerare laminated in this order, and a ratio [conductive adhesive layer/insulating layer] of Martens hardness of the conductive adhesive layerin accordance with ISO14577-1 to Martens hardness of the insulating layerin accordance with ISO14577-1 is 0.3 or more.

Electromagnetic wave shielding film

Provided is a ground member that can prevent damage to interlayer adhesion between a conductive layer and an adhesive layer of the ground member due to heating in producing a shielded printed wiring board or in mounting an electronic component on a shielded printed wiring board. The ground member of the present invention includes: a conductive layer; and an adhesive layer stacked on the conductive layer, the adhesive layer containing a binder component and hard particles, the adhesive layer having a thickness of 5 to 30 &#x3bc;m.

Ground member and shielded printed wiring board

There is provided a conductive adhesive with which the connection stability between objects that are conductive members is excellent, the connection stability is maintained even when the conductive adhesive is subjected to high temperature, and rising towards the back side of an object is less likely to occur. A conductive adhesiveincludes a binder component, and metal particles (A)having a 20% compressive strength of 25 MPa or less in a 170&#xb0; C. environment. The metal particlespreferably include a metal having a melting point of 280&#xb0; C. or less. The content of the metal having a melting point of 280&#xb0; C. or less in the metal particles (A)is preferably 80% by mass or more.

Conductive adhesive

Provided is a shielded printed wiring board that exhibits excellent connection stability even when having a through-hole with a small opening area, and enables a high degree of freedom in circuit design. The shielded printed wiring boardaccording to the present invention includes a printed wiring board, an insulating layer, and a conductive adhesive layerdisposed between the printed wiring boardand the insulating layer. The printed wiring boardincludes a base, a circuit patterndisposed on the base, and an insulating protective layercovering the circuit pattern. The shielded printed wiring board has a through-holefor external grounding that vertically penetrates the insulating layerand the conductive adhesive layer. The conductive adhesive layerhas an extensionextending toward the inside of the through-holeas compared with the insulating layer

Shield printed wiring board and method of manufacturing shield printed wiring board

The present invention aims to provide a ground member that can be mounted on any position, wherein misalignment is less likely to occur between conductive filler particles of the ground member and a shielding layer of a shielding film when a shielded printed wiring board including the ground member is repeatedly heated and cooled to mount components thereon. The ground member of the present invention includes: a conductive external connection member having a first main surface and a second main surface opposite to the first main surface; conductive filler particles disposed adjacent to the first main surface; and an adhesive resin for fixing the conductive filler particles to the first main surface, wherein each conductive filler particle includes a low-melting-point metal.

Ground member, shielded printed circuit board, and method for manufacturing shielded printed circuit board

A printed wiring board includes a base member that includes a ground wiring pattern and a printed wiring board reinforcing member bonded to the ground wiring pattern in a conductive state. The printed wiring board reinforcing member includes a metal base material layer and a nickel layer bonded to at least a surface on a side opposite to a side bonded to the ground wiring pattern of the metal base material layer by diffusion bonding.

Growing community of inventors

Kizugawa, Japan

Yuusuke Haruna