Abstract: A method of manufacturing a printed circuit board is disclosed. The method comprises steps of providing a substrate for the printed circuit board, forming circuit patterns on one or both sides of the substrate, and shielding the whole or a required part of the circuit patterns by using a shield layer in such a manner that the shield layer and a grounding circuit of the circuit patterns are connected through a resistor. This method of manufacturing a printed circuit board is improved so that adhesion between the shield layer and the junction land of the grounding circuit is enhanced by the joining of the shield layer to the junction land of the grounding circuit through the resistor, and that the noise preventive action of the shield layer is improved by the attenuating of electromagnetic-wave energy received by the shield layer which is to be discharged as electrical current to the grounding circuit.

Abstract: A method of manufacturing a printed circuit board for use in an electronic circuit is disclosed. The method comprises steps of forming a printed circuit on an insulating base board, of forming a circuit portion to be connected to the printed circuit by adhering a conductive ink on the base board, and of adhering the conductive ink through an uneven surface formed on a terminal portion to be connected to the printed circuit.

Abstract: An automatic silk stretching apparatus for stretching silk on a silk screen printing frame is provided. At first silk is stretched to four sides by first stage stretching by cramp table and second stage stretching by stretchers on the cramp table. From lower side of the cramped silk, a printing frame on an elevator table is lifted and urges the silk. Adhesive is applied on the frame, and is forcibly dried. Then, the excess silk surrounding the frame is cut. The silk stretched frame is discharged, an empty frame is fed and further new silk is cramped.

Abstract: A process of forming solder lands in a printed wiring board manufacturing method is disclosed. The process comprises a step of forming a wiring circuit of a required pattern by a copper foil provided on an electrical insulating sheet, a step of forming required solder resists on the wiring circuit, a preprinting step for leveling the surface of the wiring circuit and a step of printing required solder resist on the wiring circuit.

Abstract: A printed wiring board for use in an integrated circuit is disclosed. The printed wiring board comprises an insulating sheet having a connecting through hole portion including a possible plated through hole, a printed wiring circuit provided on one or both surface of the insulating sheet, an insulating layer provided on a part of the printed wiring circuit, an electromagnetic wave shielding layer provided on the insulating layer and a part of the printed wiring circuit, a solder resist provided on the electromagnetic wave shielding layer and a sealing member of heat-resistant material or weather-resistant material which is filled or packed in the connecting through hole portion.

Abstract: A double sided or multi-layered printed circuit board comprises an insulating substrate having conductors on opposed major surfaces thereof which are electrically connected together via a through-hole. A sealing member composed of conductive resin fills the through-hole. An insulating layer covers the conductors and sealing member, and an electronic wave-shielding layer covers the insulating layer.

Abstract: A printed wiring board having electromagnetic wave shielding layer for use in the integrated semiconductor circuit is disclosed. The printed wiring board comprises an insulating sheet, printed wiring circuits and grounded wiring circuit which are provided on one surface of the insulating sheet, an insulating layer provided on the surface of the insulating sheet, the printed wiring circuit and the grounded wiring circuit, an electromagnetic wave shielding layer provided on the insulating layer and having a portion contacted to the ground wiring circuit directly, and an over-coating layer provided on the electromagnetic wave shielding layer and having exposed portions placed over the contacted portion of the shielding layer.

Abstract: An automatic silk stretching apparatus for stretching silk on a silk screen printing frame is provided. At first silk is stretched to four sides by first stage stretching by cramp table and second stage stretching by stretchers on the cramp table. From lower side of the cramped silk, a printing frame on an elevator table is lifted and urges the silk. Adhesive is applied on the frame, and is forcibly dried. Then, the excess silk surrounding the frame is cut. The silk stretched frame is discharged, an empty frame is fed and further new silk is cramped.

Abstract: An apparatus for chamfering the outer edges of stacked printed circuit boards comprises a detecting device for detecting the boundary between two adjacent boards, and a chamfering tool positionable adjacent to the opposed outer edges of respective ones of the two adjacent boards in response to detection of the boundary and movable along the board outer edges to simultaneously chamfer both outer edges. The chamfering tool successively chamfers pairs of opposed outer edges in the upward direction on one side of the stack, and then the stack is turned so that the chamfering tool chamfers the outer edges on a different side of the stack printed circuit boards.

Abstract: Disclosed are a method of filler taping a screen frame and a method of filling a screen frame. The screen frame is held in such a manner as to be indexable 90 degrees, a tape is attached simultaneously on opposing two sides of the screen frame through linear motion. At the same time, a filling liquid is applied simultaneously on opposing two sides of the screen frame on the rear surface thereof. Subsequently, the screen is rotated 90 degrees, and taping and filling are similarly effected with respect to the remaining two sides.

Abstract: A planar surface of an article is ground smooth by a two-stage grinding head having an upstream-stage grinding brush and a downstream-stage grinding stone. The article is advanced past the grinding head while the grinding head is eccentrically driven so that the grinding brush coarsely grinds the planar surface and forms therein spiral brush traces and the grinding stone finely grinds the coarsely ground planar surface to smoothen the brush traces.

Abstract: An apparatus for surface grinding a planar surface of an article comprises a two-stage grinding head having an upstream-stage grinding brush and a downstream-stage grinding stone. The article is advanced past the grinding head while the grinding head is eccentrically driven so that the grinding brush coarsely grinds the planar surface and forms therein spiral brush traces and the grinding stone finely grinds the coarsely ground planar surface to smoothen the brush traces.

Abstract: The present invention relates to a printed wiring board, and more particularly to a solder resist film applied on the printed wiring board, and to solder resist printing ink utilized to form such solder resist film.

Abstract: A method of chamfering the outer peripheral edges of plate members comprises stacking the plate members in face-to-face vertically aligned relation so that for each two adjacent plate members the upper outer peripheral edge of the lower plate member opposes the lower outer peripheral edge of the upper plate member, detecting the boundary between two adjacent plate members in the stack, positioning a rotary chamfering tool in response to detection of the boundary, and moving the rotary chamfering tool relative to the outer peripheral edges of the two adjacent plate members to simultaneously chamfer the upper edge of the lower plate member and the lower edge of the upper plate member. The detecting, positioning and chamfering steps are repeated for each two adjacent plate members in the stack to thereby chamfer both the upper and lower edges of the stacked plate members.

Abstract: The invention relates to a printed wiring board (7) which includes at least one carbon resistor (3) formed across terminals (2a, 2b) of printed wiring circuit (2). A heat dissipating film layer (4) is formed at least on the carbon resistor (3). Thus, heat produced in the resistor (3) is effectively dissipated.

Abstract: Outer surface of a printed circuit board having circuit conductors on one or both surfaces may be covered by shield film or layer to shield outer noise from reaching the circuit conductors. To shield cross talk and noise from reaching each other, all electrically exposed surfaces of the circuit conductors are covered also by shield film.

Abstract: A printed circuit board comprises a base plate and a circuit conductor formed on at least one of the opposed surfaces of the base plate. A heat-radiating film is formed on at least a portion of the surface of the circuit conductor, and an insulating film is formed over the exposed surfaces of the heat-radiating film and the circuit conductor. At least one opening is formed in the insulating film, and the opening overlies the heat-radiating film thereby directly exposing the heat-radiating film to ambient atmosphere so as to promote dissipation of heat from the circuit conductor during use of the printed circuit board. The opening in the insulating film may be in the form of a slot or may comprise a pattern of circular or oval openings. The heat-radiating film may be copper or nickel paste, or non-organic material such as aluminum oxide.

Abstract: A printed wiring board includes a dielectric base plate, a circuit pattern at least on one surface of the base plate, and a solder resist film containing silicon series and/or fluorine series and covering the base plate except a desired soldering area of the circuit pattern. The solder resist film has solder repelling property to prevent bridging of solder across adjacent circuits. However, the solder repelling property apts to form dots on the solder resist film. Accordingly, at least one flux accumulating portion is formed on said one surface of the base plate to accumulate flux repelled by the solder resist film. The flux accumulating portion may be a recess and/or through-hole arranged on the surface of the solder resist film.