Abstract: Novel aromatic diisocyanate and a method of producing the same. The method comprises reacting a diamine compound with a chloroformate to produce an urethane intermediate, and then reacting the urethane intermediate with a halogenated organosilicon compound or a halogenated organoboron compound, using an organic solvent capable of dissolving both the diamine compound and the urethane intermediate. This method enables to produce the aromatic diisocyanate by one-pot. The aromatic diisocyanate has excellent various properties such as high heat resistance and chemical resistance.

Abstract: A heat-resistant negative-working photoresist composition comprising a resin component having a carbodiimide unit in the molecule, and a compound capable of inducing a basic compound by irradiation with actinic rays. The photosensitive layer formed by the photoresist composition shows a sufficient sensitivity even by a lower irradiation energy and can give a sharp negative-type pattern by irradiation with actinic rays such as ultraviolet rays.

Abstract: A heat-resistant negative-working photoresist composition comprising a resin component having a carbodiimide unit in the molecule, and a compound capable of inducing a basic compound by irradiation with actinic rays. The photosensitive layer formed by the photoresist composition shows a sufficient sensitivity even by a lower irradiation energy and can give a sharp negative-type pattern by irradiation with actinic rays such as ultraviolet rays.

Abstract: A heat-resistant adhesive film, an adhesion structure obtained using the same, and an adhesion method using the same are disclosed, the film comprising a polyisoimide resin containing at least 40 mol % of an isoimide unit represented by formula (I): ##STR1## wherein R.sub.1 represents a tetravalent aromatic or aliphatic residue; R.sub.2 represents a divalent aromatic or aliphatic residue; and the arrow represents a bond replaceable on isomerization, in the molecule thereof. The isoimide unit of the polyisoimide resin is easily converted to an imide unit on heating, e.g., hot pressing with an adherend, to provide a cover-lay film or a single-sided or double-sided base for printed circuit boards having excellent adhesion, heat resistance, dimensional precision, and workability.

Abstract: An anisotropic electrically conductive adhesive film having fine through holes independently electroconductively passing through an insulating film in the thickness direction, at least one end portion of both the end portions of the each through hole on the front and back surfaces of said film being blocked with a bump-form metal projection having a larger base area than the area of the opening portion of the through hole, wherein the insulating film comprises a thermoplastic polyimide resin having a melt viscosity at 400.degree. C. of not higher than 1.times.10.sup.8 poise is disclosed. The film is interposed between materials to be connected to provide a connection structure.

Abstract: A method of mounting a semiconductor device including a film carrier having an insulating film having on one side thereof a connecting lead and a semiconductor element junctioned with the film carrier on an outer substrate, which includes forming an opening for adhesive forcing or adhesive injection in the insulating film within its bonding area to be in contact with a land part on the outer substrate and in an area near the bonding area, connecting the connecting lead to the land part on the outer substrate, and forcing or injecting an adhesive through the opening formed in the insulating film into the space between the film carrier and the outer substrate.

Abstract: A flexible printed substrate imparted with an adhesive property for loading on an external substrate, a double printed substrate having formed on both surfaces thereof a metal layer or a wiring circuit, and a multilayer substrate having a multilayer structure are disclosed. The flexible printed substrate comprises an insulating resin layer comprising a low-linear expansion polyimide resin layer and a thermoplastic polyimide resin layer, and a metal layer or a wiring circuit formed on the low-linear expansion polyimide resin layer of the insulating resin layer, wherein a mixed region of the polyimide resin components is formed in the interface between the low-linear expansion polyimide resin layer and the thermoplastic polyimide resin layer.

Abstract: An anisotropic conductive film is disclosed, comprising an insulating film having fine through-holes independently piercing the film in the thickness direction, each of the through-holes being filled with a metallic substance in such a manner that at least one end of each through-hole has a bump-like projection of said metallic substance having a bottom area larger than the opening of the through-hole. The metallic substance serving as a conducting path is prevented from falling off, and sufficient conductivity can be thus assured.

Abstract: An anisotropic conductive film is disclosed, comprising an insulating film having fine through-holes independently piercing the film in the thickness direction, each of the through-holes being filled with a metallic substance in such a manner that at least one end of each through-hole has a bump-like projection of said metallic substance having a bottom area larger than the opening of the through-hole. The metallic substance serving as a conducting path is prevented from falling off, and sufficient conductivity can be thus assured.

Abstract: The present invention provides a process for producing a metal/polyimide composite article such as high-density wiring boards. This metal/polyimide composite article is produced by a method which comprises coating a polyamic acid alkyl ester represented by the following formula on a metallic film and curing it: ##STR1## wherein R.sub.1 and R.sub.2 which may be identical or different each represents an organic group of 1 or more carbon atoms.

Abstract: A wiring substrate, a film carrier, a semiconductor device made by using the film carrier, and a mounting structure comprising the semiconductor device are disclosed.The wiring substrate comprises:a conductor pattern which has a bonding pad and is formed on the rear surface of an insulating support;at least one of minute through-holes which are provided in a region of the insulating support where the bonding pad is in contact therewith, or which are provided a region of the insulating support where the bonding pad is in contact therewith and in the vicinity of the region, the through-holes running in the direction of the thickness of the insulating support;a conductive passage which is made of a metal material and which is formed in the through-holes that are provided in a region of the insulating support where the bonding pad is in contact therewith; anda bump-like metal protrusion which is formed on the conductive passage and which is protruded from the front surface of the insulating support.

Abstract: A positively photosensitive polyimide composition is disclosed, which composition comprises polyimide having repeating unit represented by formula (I): ##STR1## wherein Ar.sup.1 represents a tetravalent aromatic hydrocarbon group; Ar.sup.2 represents a divalent aromatic hydrocarbon group having an acyloxy group at the ortho-position and/or the meta-position of the aromatic ring; Ar.sup.3 represents a divalent aromatic hydrocarbon group; and the subunit having an amount ratio of m in the repeating unit is present in an amount of at least 20% by weight based on the polyimide. The composition exhibits high photosensitivity in reproduction of a fine pattern and excellent dimensional stability.