Abstract: A double-sided flexible circuit board with enhanced rigidity of terminals by using copper foil on an opposite side of the circuit board is provided. The flexible circuit board having wiring patterns P for connecting terminals on each of a front surface A and a back surface B of its periphery, includes: terminal patterns with linear-planar-shaped traces, the traces of which are equally spaced and disposed on the peripheries of each of the front surface and the back surface of the board; and backing patterns with planar-shaped traces, the traces of which are combined with the terminal patterns and bent so that the central portion of the backing pattern is offset from that of the terminal pattern, wherein the traces of the backing patterns are disposed on the corresponding opposite side of the traces of the terminal patterns on the board so as to be positioned overlapping with the traces of the terminal patterns.

Abstract: It is an object of the present invention to provide a printed circuit board and an inspection method therefor capable of electrically inspecting misregistration of a solder resist and a display by silk printing with respect to a wiring pattern on a printed circuit board. The present invention provides a printed circuit board provided with a conductive layer for electromagnetic shielding including at least two targets 11, 12 formed as conductive patterns of the same shape on the printed circuit board, insulating layers 21, 22, 23, 4 greater than the targets and analogous to the targets provided in such a way as to be overlaid on the targets and an electromagnetic shielding layer 3 provided on the insulating layers, and an inspection method using the printed circuit board.

Abstract: The invention is directed toward a method of manufacturing a flexure blank whereby an opening portion is provided in a in a connecting portion of a flexure blank, an opening end portion of an insulating base layer is coated with a conductive member without exposing the opening end portion of the insulating base layer in the connecting portion, and a lower surface of the conductive member of the opening portion in the connecting portion of the flexure blank is structured such as to form the same surface as the lower surface of the insulating base layer.

Abstract: A multilayered circuit board has good imbedding properties for circuit patterns, and an interlayer insulating material having superior adhesive force and interlayer insulating properties. In a multilayered circuit board wherein interlayer connection is achieved by the contact of minute pointed protrusions, provided on a first conductive circuit layer, with a second conductive circuit layer, interlayer insulation is achieved by a film having a three-layer structure, comprising a thermoplastic film inserted between a pair of thermosetting adhesive layers.

Abstract: A multilayered circuit board has good imbedding properties for circuit patterns, and an interlayer insulating material having superior adhesive force and interlayer insulating properties. In a multilayered circuit board wherein interlayer connection is achieved by the contact of minute pointed protrusions, provided on a first conductive circuit layer, with a second conductive circuit layer, interlayer insulation is achieved by a film having a three-layer structure, comprising a thermoplastic film inserted between a pair of thermosetting adhesive layers.

Abstract: In case of manufacturing a flexible multilayer circuit board which comprises an internal layer circuit board which can be a cable portion and an external layer circuit board which can be a component mounting portion laminated on one side or both sides of the internal layer circuit board at a predetermined position and which has a through hole plated conduction portion 12 formed at predetermined positions of the internal layer circuit board and the external layer circuit board, surface protection layers 3 and 5 formed on external surfaces of wiring patterns 1 and 4 of the internal layer circuit board are formed in a region retreated toward the outside from a position of a through hole 13 for a through hole plated conduction portion 12.

Abstract: An internal layer circuit board to which an opening portion 14 is provided at a predetermined position and a required wiring pattern 1 is formed so as to expose a terminal portion 1A to the opening portion 14 is manufactured. Subsequently, single-sided copper-clad laminates are superimposed on both sides of the internal layer circuit board through interlayer adhesive layers 6 and 7 to which another opening portion 14 is provided at a position corresponding to the opening portion 14, and two piercing slits S are previously formed to the single-sided copper-clad laminate at corresponding positions placed outside from edges of the opening portion 14 by a predetermined distance in accordance with two opposed sides of the opening portion 14.

Abstract: A required interlayer circuit board 1 is constituted so as to provide a punched portion in which only a collapsible cable portion 2 for connecting a plurality of component mounting portions to each other is exposed. An external layer board 6 is superimposed on at least one side of the internal layer circuit board 1 through an adhesive member 4 to which an opening portion 5 is formed at a position corresponding to the cable portion 2, the external layer substrate 6 having an opening portion 7 at a similar position. Thereafter, a wiring pattern for the component mounting portions is formed on the external layer board 6, and a blank and pierce process of the respective component mounting portions except the cable portion is carried out, thereby integrally connecting a plurality of the component mounting portions to each other through the collapsible cable portion.

Abstract: A flexible printed circuit board including a component mount section, which an electronic component is mounted on, and a cable section, which connects to the component mount section; circuit patterns being provided on the cable section, and covered by a soft laminated adhesive.

Abstract: A fluoroelastomer composition comprising (1) a fluoroelastomer consisting essentially of tetrafluoroethylene units, perfluoro(alkyl vinyl ether) units and cyano group containing perfluorovinyl ether units; (2) a specified silane coupling agent; (3) a crosslinking agent and (4) an inorganic filler. This fluoroelastomer composition enables improving the moldability of a crosslinkable composition containing an inorganic filler other than carbon black.

Abstract: Polyimide is produced by reacting two kinds of diamine compounds consisting of diaminopolysiloxane and a carboxyl group-containing diamine or three kinds of diamine compounds consisting of diaminopolysiloxane, a carboxyl group-containing diamine and an aromatic or alicyclic diamine with a dicarboxylic acid anhydride having a 2,5-dioxotetrahydrofuryl group as one acid anhydride group, thereby once forming a polyamic acid, and subjecting the polyamic acid to polyimidization reaction. The resulting polyimide itself is soluble in low boiling organic solvents for general purpose use, typically methyl ethyl ketone. A photosensitive composition comprising the polyimide, a photo crosslinking agent and a photo acid-generating agent forms a negative type polyimide pattern upon development with an aqueous alkali solution.

Abstract: In order to realize through hole conduction of an internal layer wiring pattern 4 and respective external layer conduction layers 2 and 5 on both sides, a through hole partially blocked is formed to the internal layer wiring pattern 4 from one external layer conduction layer 2 by laser means. Similarly, another through hole which is partially blocked and displaced from the former hole within an allowable range is formed to the internal layer wiring pattern 4 from the other external layer conduction layer 5 by the laser means, thereby forming a stepped through hole 6. At last, a through hole coating layer 7 is formed.

Abstract: An opening portion is provided in a connecting portion of a flexure blank, an opening end portion of an insulating base layer is coated with a conductive member without exposing the opening end portion of the insulating base layer in the connecting portion, and a lower surface of the conductive member of the opening portion in the connecting portion of the flexure blank is structured such as to form the same surface as the lower surface of the insulating base layer.

Abstract: The polymerization initiator-containing solution obtained by mixing a specific perfluorodicarboxylic acid fluoride (A) with CsF in an aprotic polar solvent with stirring to conduct reaction and thereby form a polymerization initiator (B) and then allowing the reaction solution to stand for not less than 72 hours at a temperature of 0 to 30° C. A polymerization initiator-containing solution comprises a specific polymerization initiator (B′) and an aprotic polar solvent. The process for preparing a perfluoropolyether comprises polymerizing hexafluoropropylene oxide in the presence of the polymerization initiator-containing solution.

Abstract: A flexible printed circuit board including a component mount section, which an electronic component is mounted on, and a cable section, which connects to the component mount section; circuit patterns being provided on the cable section, and covered by a soft laminated adhesive.

Abstract: A fluoroelastomer comprising constituent units derived from vinylidene fluoride (a) and constituent units derived from perfluoro(methoxypropyl vinyl ether) (b), optionally together with constituent units derived from tetrafluoroethylene (c) and/or constituent units derived from a perfluoroalkyl vinyl ether (d), wherein the constituent units (a) are contained in an amount of 65 to 85 mol %, the constituent units (b) in an amount of 0.5 to 30 mol %, the constituent units (c) in an amount of 0 to 10 mol % and the constituent units (d) in an amount of 0 to 25 mol %. The fluoroelastomer can be produced by a process comprising copolymerizing vinylidene fluoride and perfluoro(methoxypropyl vinyl ether), optionally together with tetrafluoroethylene and/or a perfluoroalkyl vinyl ether, in the presence of an iodated brominated compound represented by the general formula RBrnIm [I]. Further, there is provided a crosslinkable composition comprising the above fluoroelastomer and a peroxide crosslinking agent.

Abstract: Disclosed is a fluorocopolymer obtained by copolymerizing specific amounts of vinylidene fluoride, a perfluoro(lower alkyl vinyl ether), a specific fluorine compound represented by the following formula (I), a bromine-containing and/or iodine-containing vinyl monomer, and optionally, tetrafluoroethylene 1

Abstract: The polymerization initiator-containing solution of the first invention is obtained by mixing a specific perfluorodicarboxylic acid fluoride (A) with CsF in an aprotic polar solvent with stirring to conduct reaction and thereby form a polymerization initiator (B) and then allowing the reaction solution to stand for not less than 72 hours at a temperature of 0 to 30° C. The polymerization initiator-containing solution of the second invention comprises a specific polymerization initiator (B′) and an aprotic polar solvent. The process for preparing a perfluoropolyether according to the invention comprises polymerizing hexafluoropropylene oxide in the presence of the polymerization initiator-containing solution.

Abstract: Disclosed is a fluoroelastomer composition comprising (1) a fluoroelastomer which comprises (a) tetrafluoroethylene, (b) a perfluoro(C1-C5 alkyl vinyl ether) and/or a perfluoro(C3-C11 alkoxyalkyl vinyl ether) and (c) a cyano group-containing perfluorovinyl ether, (2) a hydrotalcite compound, (3) a crosslinking agent and (4) titanium dioxide (TiO2). The fluoroelastomer composition is capable of producing a fluoroelastomer molded product having excellent metal corrosion inhibition properties, and particularly, the fluoroelastomer composition is capable of producing a fluoroelastomer molded product which generates only small amount of a corrosive material when exposed to high temperature.

Abstract: Disclosed is a fluoroelastomer composition comprising (1) a fluoroelastomer which comprises tetrafluoroethylene, a perfluoro (C1-C5 alkyl vinyl ether) or a perfluoro (C3-C11 (alkoxyalkyl) vinyl ether) and a cyano group-containing perfluorovinyl ether, (2) a hydrotalcite compound, (3) a crosslinking agent and (4) carbon black. The fluoroelastomer composition has excellent metal corrosion inhibition properties, and particularly, this composition generates only small amount of a corrosive material when exposed to high temperatures.