Nitto-denko Corporation

Nitto Electric Industrial Co., Ltd.

Shunichi Hayashi

Hirofumi Fujii

Amane Mochizuki

Takahiro Fukuoka

Kazunori Mune

Kazumi Higashi

Yutaka Yamamura

Ryusuke Naitou

Takahiro Yoshioka

Tomomichi Kaneko

Hideto Suzuki

A photosensitive polyimide resin precursor composition capable of providing a polyimide resin that is not substantially colored, is transparent and has heat resistance, an optical polyimide resin obtained from the composition, and an optical waveguide using the polyimide resin. The photosensitive polyimide resin precursor composition contains (a) 100 parts by weight of a polyamic acid obtained from a tetracarboxylic acid dianhydride and a diamine, (b) 0.01 parts by weight or more and less than 5 parts by weight of a 1,4-dihydropyridine derivative, (c) 5&#x2013;50 parts by weight of a glycol (ether). The optical polyimide resin is obtained by irradiating the photosensitive resin precursor composition with UV light, followed by exposure, heating, development, and then heating. The optical waveguide comprises a core layer comprising the optical polyimide resin, and a cladding layer thereof.

Photosensitive polyimide resin precursor composition, optical polyimide obtained from the composition, optical waveguide using the polyimide, and process for producing the optical waveguide

A method for manufacturing wired circuit board that enables a wired circuit board of high quality to be manufactured without changing in dimension of the wired circuit board substantially. In this method, the wired circuit board is wound in layers in the winding process in such a manner that after an uncured thermosetting resin layer is formed on the wired circuit board in the resin layer forming process, a right-side spacer and a left-side spacer are disposed on the already wound wired circuit board at both widthwise ends thereof and also an upper spacer is disposed on the right-side spacer and the left-side spacer so as to cover a widthwise area of the wired circuit board, so that the right-side spacer, the left-side spacer and the upper spacer are positioned between the layers of the wired circuit board when wound. Thereafter, the wired circuit board wound in the rolled state is heated as it is, to cure the uncured thermosetting resin layer in the curing process.

Method for manufacturing wired circuit board

A photosensitive resin composition which is excellent in both sensitivity and resolution, can be rapidly developed with an aqueous alkali solution alone, further has excellent adhesion to substrates, and can give through imidization a light-colored polyimide resin film; and a circuit board having an insulating layer obtained from the photosensitive resin composition. The photosensitive resin composition comprises a poly(amic acid) resin, a 1,4-dihydropyridine derivative and a polyethylene glycol, and may optionally further contain a polyhydric phenol compound. This photosensitive resin composition can be developed at a high rate with a developing solution consisting only of an aqueous alkali solution. As a result, a satisfactory negative-pattern film which is a light-colored film can be formed with high sensitivity, high resolution, and a reduced film loss while preventing film coloration.

Photosensitive resin composition and circuit board

The present invention provides a resin composition for a wiring circuit board; a substrate for a wiring circuit board in which a base insulating layer has been formed from the resin composition for a wiring circuit board; and a wiring circuit board having insulating layers including a cover insulating layer formed from the resin composition for a wiring circuit board. The resin composition for a wiring circuit board, the substrate for a wiring circuit board, and the wiring circuit board can prevent warpage and curling, increase adhesion between the insulating layer and the conductor layer, and enhance the durability and reliability of the wiring circuit board. The resin composition for a wiring circuit board contains a polyimide resin precursor, and a polyhydric phenol compound.

Resin composition for wiring circuit board, substrate for wiring circuit board, and wiring circuit board

A negative photoresist composition is disclosed which is excellent in sensitivity and resolution, tenaciously adheres to substrates, and can be advantageously used in practical production processes. Two 1,4-dihydropyridine derivatives each having a specific structure are incorporated as photosensitizers into a polyamic acid to obtain the negative photoresist composition.

Negative photoresist composition

Negative-working photoresist compositions and and use thereof

A method of peel development comprising laminating an image-forming material comprising a transparent support and a photopolymerizable composition layer on the surface of a substrate on which an image is formed, imagewise exposing the image-forming material, and peeling the support from the substrate together with the unexposed areas of the photopolymerizable composition layer while leaving the exposed areas thereof on the substrate, wherein the cohesive strength of the photopolymerizable composition layer is set such that the force required to separate the unexposed areas from the exposed areas is at least 1.0 kg/mm.sup.2 and the peeling operation is performed while maintaining a peel angle (.alpha.) of the support to the substrate within the range of 0.degree.&lt;.alpha..ltoreq.90.degree.. This method enables the formation of sharp images on the substrate while allowing for the easy separation of the unexposed areas from the exposed areas.

Method of peel development

In an epoxy resin composition for sealing a semiconductor element containing about 50 to 85% by weight of an inorganic filler, the improvement wherein the inorganic filler comprises at least a silica powder and a calcium silicate powder, and the amount of said calcium silicate powder is about 20 to 75% by weight and the amount of the silica powder is about 25 to 80% by weight based on the total weight of the silica powder and calcium silicate powder.

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Osaka, Japan

Shunichi Hayashi