Abstract:
A production method for a copper-clad laminated sheet, which can eliminate defective dents occurring when an outer-layer copper foil layer is pasted, by using a build-up construction, to an inner-layer substrate provided with through holes or recesses serving as inter-layer conducting means such as interstitial via holes (IVH) and blind via holes (BVH), the method characterized by using, as outer-layer copper foil, (1) resin-carrying copper foil having a resin layer formed on one surface of copper foil having a bulge-test rupture strength after heating of at least 275 KN/m2 and a thickness of at least 15 νm, (2) an etchable type carrier-foil-carrying copper foil having a total thickness of the carrier foil layer and the copper foil layer of at least 20 νm, or (3) peelable carrier-foil-carrying copper foil having a total thickness of the carrier foil layer and the copper foil layer of at least 20 νm and a peeling strength after heating of 5 gf/cm to 300 gf/cm at the joint interface between the two layers, to thereby obtain the copper-clad laminated sheet.
Abstract:
Method and apparatus of fabricating a core laminate Printed Circuit Board structure with highly planar external surfaces is provided. A pre-formed flat material including a first resinous sub-material and a second carrier sub-material is used to planarize external surfaces. During lamination, uniform pressure is applied to the pre-formed flat sheet which covers the upper surface of the printed circuit. The resinous material of the first sub-material flows to fill the crevices, vias, etc. of the upper surface of the PCB. Moreover, due to the uniform pressure on the pre-formed flat sheet, the resinous first sub-material is planarized. This planarized surface provides a suitable base substrate for a thin film multilayer build-up structure and that provides electrical connections between the thin film top layers and the Printed Circuit Board - style core layers.
Abstract:
A resin-coated copper foil for multilayer printed wiring boards characterized by having a resin composition applied to one side thereof, wherein the composition comprises 50-90 wt.% of an epoxy resin, 5-20 wt.% of a polyvinyl acetal resin and 0.1-20 wt.% of a urethane resin, and wherein a rubber-modified epoxy resin accounts for 0.5-40 wt.% of the whole epoxy resin.
Abstract:
An adhesive for copper foils comprises (I) 60 to 100 parts by weight of the whole epoxy resin including 0.5 to 20 parts by weight of a rubber-modified epoxy resin, and (II) 5 to 30 parts by weight of a polyvinyl acetal resin; and an adhesive-backed copper foil has the adhesive coated on its one surface.
Abstract:
A process for producing a multilayer printed circuit board, which comprises: laminating an interlayer plate having conductor circuits thereon with a thermosetting copper-clad adhesive resin sheet having a copper foil on one side, so as to make the resin side of the sheet contact with the interlayer plate, followed by curing the resin to give an integrated laminate, the thermosetting copper-clad adhesive resin sheet being obtainable by integrating a copper foil with a thermosetting epoxy resin composition comprising (a) an epoxy polymer having a weight-average molecular weight of 100,000 or more, obtainable by polymerizing a bifunctional epoxy resin and a bifunctional halogenated phenol in an equivalent weight ratio of epoxy group:phenolic hydroxyl group of from 1:0.9 to 1:1.1, (b) a crosslinking agent, and (c) a polyfunctional epoxy resin; forming an etching resist on the copper foil of the integrated laminate, followed by formation of fine holes in the copper foil surface by selective etching; removing the remaining etching resist, removing the cured resin layer under the fine holes by etching using an etching solution comprising (A) an amide as a solvent, (B) an alkali metal compound, and (C) an alcohol as a solvent to form via holes and expose parts of the conductor circuits; plating a metal layer or coating an electroconductive paste so as to electrically connect the conductor circuits of the interlayer plate and the outer layer copper foil; forming an etching resist on the outer layer copper foil, followed by formation of wiring circuits on the copper foil by selective etching; and removing the remaining etching resist.
Abstract:
A resin composition comprising (a) an epoxy resin having a number average molecular weight of 1200 or less, (b) a carboxylic acid-containing acrylic or acrylonitrile-butadiene rubber, (c) a curing agent for the epoxy resin, and (d) a curing accelerator is easily chemically etched and suitable as an insulating adhesive for producing multilayer printed circuit boards.
Abstract:
This invention relates to an adhesive composition, comprising: (A) at least one phenolic resole resin; and (B) the product made by reacting (B-1) at least one difunctional epoxy resin, with (B-2) at least one compound represented by the formula
wherein in Formulae (I) and (II): G, T and Q are each independently functional groups selected from the group consisting of COOH, OH, SH, NH₂, NHR¹, (NHC(=NH)) m NH₂, RCOOH, NR¹₂, C(O)NHR¹, RNR¹₂, ROH, RSH, RNH₂ and RNHR¹, wherein R¹ is a hydrocarbon group, R is an alkylene or alkylidene group and m is a number in the range of 1 to about 4; T can also be R¹, OR¹ or SO₂C₆H₄-NH₂; and Q can also be H. The invention also relates to copper foils having the foregoing adhesive composition adhered to at least one side thereof to enhance the adhesion between said foils and dielectric substrates. The invention also relates to laminates comprising copper foil, a dielectric substrate, and an adhesion-promoting layer comprising the foregoing adhesive composition disposed between and adhered to the foil and the substrate.
Abstract:
A heat resistant adhesive composition comprising a specific polyamic acid solution and a bis-maleimide compound exhibits flexibility and excellent heat resistance after bonding two material bodies, and therefore, it can be suitably used for producing of flexible metal-clad laminates, double-sided flexible metal-clad laminates, and multilayer printed circuit boards, and for attaching coverlay films to printed circuit boards.