Taiyo Ink Manufacturing Co., Ltd.

Masao Arima

Akio Sekimoto

Kyoichi Yoda

Shigeru Komori

Norio Kimura

Masashi Sugita

Kazuo Suda

Miyako Juni

A liquid thermosetting filling composition comprising (A) an epoxy resin assuming a liquid state at room temperature, (B) a phenolic resin assuming a liquid state at room temperature, (C) a curing catalyst, and (D) an inorganic filler is useful as an ink for permanently filling such holes as via holes and through holes in printed circuit boards of a multilayer board or a double-sided board, a sealing compound for IC packages, and the like. This composition is a two-stage thermally curing type. In a method for permanently filling holes in a printed circuit board, the composition is applied to the board so as to fill the holes in the printed circuit board and precured by application of heat. The parts of the precured composition protruding from a surface defining the holes is removed by polishing and then the precured composition is further heated to cause final curing thereof.

Liquid thermosetting filling composition and method for permanently filling holes in printed circuit board by the use thereof

A photocurable and thermosetting resin composition developable with an aqueous alkali solution is disclosed. The composition comprises in combination: (A) a photosensitive prepolymer soluble in a dilute aqueous alkali solution obtained by esterifying an epoxy resin represented by the following general formula (1) with (meth)acrylic acid and further adding an acid anhydride thereto until an acid value reaches a level in the range of 60 to 120 mg KOH/g, (B) a diglycidyl ether type epoxy compound containing two epoxy groups in the molecular unit thereof, (C) a photopolymerization initiator, and (D) a diluent at such ratios of combination that said epoxy compound (B) accounts for a proportion in the range of 5 to 120 parts by weight and said photopolymerization initiator (C) for a proportion in the range of 0.1 to 30 parts by weight, based on 100 parts by weight of said photosensitive prepolymer (A): ##STR1## wherein X represents CH.sub.2, C(CH.sub.3).sub.2, or SO.sub.2, n is an average value in the range of 1 to 12, and Y represents a hydrogen atom or a glycidyl group, providing that Y is a glycidyl group where n is 1 and at least one of the plurality of Y's is a glycidyl group where n is 2 or more.

Photocurable thermosettting resin composition developable with aqueous

A one-package type photosolder resist developable with an aqueous alkali solution and suitable for use as a solder resist for a printed circuit board is disclosed. The composition comprises (A) a copolymeric macromolecular compound containing at least one free carboxyl group in the molecular unit thereof or (A') a copolymeric macromolecular compound containing at least one free carboxyl group and at least one photoreactive unsaturated group in the molecular unit thereof and assuming a solid state at normal room temperature, (B) a diluent including a polyfunctional unsaturated compound assuming a liquid state at normal room temperature and/or an organic solvent, (C) a photopolymerization initiator, (D) a vinyltriazine compound or a derivative thereof, and (E) an inorganic filler. A process for forming a solder resist on a printed circuit board having a circuit preparatorily formed thereon comprises the steps of applying to the surface of said printed circuit board the one-package type photosolder resist composition mentioned above, drying the applied layer of said composition, selectively exposing the dried layer to actinic radiation according to a prescribed pattern, developing the unexposed area of said layer with an aqueous alkali solution thereby forming a solder resist pattern, and finally curing said resist pattern by exposure to actinic radiation.

One-package photosolder resist composition developable with aqueous

Growing community of inventors

Sakado, Japan

Masao Arima