Abstract: An insulating material comprising a cycloolefin polymer, specifically, an interlayer insulating material for a high-density assembly board having interlayer-connecting via holes at most 200 &mgr;m in diameter, comprising a cycloolefin polymer containing at least 50 mol % of a repeating unit derived from a cycloolefin monomer; a dry film formed from a curable resin composition comprising a polymer having a number average molecular weight within a range of 1,000 to 1,000,000 as measured by gel permeation chromatography, and a hardener; and a resin-attached metal foil obtained by forming a film of a cycloolefin polymer on one side of a metal foil. Laminates, multi-layer laminates and build-up multi-layer laminates making use of these materials, and production processes thereof.

Abstract: A curable composition comprises an insulating resin and a halogen-free flame retardant. The halogen-free flame retardant has a particulate form, and whose primary particles have an average major axis from 0.01 to 5 &mgr;m, an aspect ratio of 5 or less, and the proportion of a major axis of more than 10 &mgr;m being at most 10% by number. A varnish comprises an insulating resin, a curing agent, a flame retardant and an organic solvent. The flame retardant is a flame retardant in particulate form surface-treated with a coupling agent, and the flame retardant particles present in the varnish have a secondary particle diameter of 30 &mgr;m or less.

Abstract: A curable composition contains an insulating resin such as an alicyclic olefin polymer or an aromatic polyether polymer, a nitrogen-type curing agent such as a 1,3-diallyl-5-glycidylisocyanurate, and an ultraviolet-ray absorbing agent such as a 2-[2-hydroxy-3,5-bis(&agr;,&agr;-dimethylbenzyl)phenyl]benzotriazole. A film is obtained from the curable composition by a solution casting method, is laminated on an inner-layer board and is cured to obtain a multi-layer circuit board.

Abstract: This invention provides a multi-layer circuit board excellent in flame resistance, insulating property and adhesion and not generating detrimental substances when burnt, and a curable composition suitable for obtaining the multi-layer circuit board. The curable composition contains an insulating resin such as an alicyclic olefin polymer or an aromatic polyether polymer, a nitrogen-type curing agent such as 1,3-diallyl-5-glycidyl isocyanurate and a phosphorus-type flame retardant such as phosphoric acid ester amide, and is molded into a film by a solution casting method. The film so formed is laminated on an internal layer board and is cured to give the multi-layer circuit substrate.

Abstract: A method for manufacturing a multilayer circuit board, in which adhesion between electrical insulating layer and a conductive layer is high and the patternability is also excellent, is provided. The method for manufacturing the multilayer circuit board comprises a step of; 1) bringing the surface of the electrical insulating layer produced by setting a setting resin composition containing an alicyclic olefin polymer or an aromatic polyether polymer into contact with a permanganic acid compound or a plasma, 2) dry-plating the surface and then wet- or dry-plating the surface, 3) dry-plating the surface several times and then wet-plating the surface, or 4) plating the surface and then annealing it, so as to form a conductive layer.

Abstract: A norbornene resin composition comprising 100 parts by weight of a thermoplastic norbornene polymer and 1 to 150 parts by weight of a thermosetting resin.

Abstract: A curable resin composition comprising a modified cycloolefin addition polymer (A) obtained by introducing a functional group into a cycloolefin addition polymer containing a repeating unit (a) derived from a cycloolefin monomer having an organic group having at least 4 carbon atoms at its side chain at a rate of introduction of the functional group of 0.1 to 50 mol % based on the whole repeating unit of the cycloolefin addition polymer, and a hardening agent (B), and a modified cycloolefin addition polymer (A) obtained by introducing a functional group into a cycloolefin addition polymer containing a repeating unit (a) derived from a cycloolefin monomer having an organic group having at least 4 carbon atoms at its side chain at a rate of introduction of the functional group of 0.1 to 50 mol % based on the whole repeating unit of the cycloolefin addition polymer, and having a weight average molecular weight (Mw) of 1,000 to 1,000,000.

Abstract: A composite film having a layer structure of at least two layers, wherein a film (A) formed from a ring structure-containing polymer comprising a repeating unit derived from ring-opening or addition polymerization of a monomer having a ring structure, and a film (B) formed from a polycondensation polymer adjoin each other directly or through an adhesive layer.