Unitika Ltd.

Nippon Kayaku Kabushiki Kaisha

Akira Shigeta

Yoshiaki Echigo

Takeshi Yoshida

Yuki Yamada

Tatsuya Morikita

Makoto Uchida

Makoto Nakai

Yumeto Fukubayashi

Munenori Yamada

Yosuke Sugimoto

Ryoichi Hasegawa

Shigeru Moteki

Minoru Noji

Jusirou Eguchi

Jun-ichi Mori

Seiichi Hayashi

An object is to provide a method for easily producing maleimide (MI) in which trace amounts of residual acid components as impurities in a crude MI are efficiently reduced, that is, the acid value is sufficiently reduced.

Production method of maleimide

An object of the present invention is to provide a bismaleimide (D-BMI) modified product in which an amino group of dimer diamine (DDA) is maleimidized, which has the good heat resistance, and has the sufficiently enhanced processability, and a method for producing the same. There are provided:

Bismaleimide modified product and method for producing the same

The present invention is to provide a polyamide-imide which has a high regularity of molecular structure and few branched structures, does not contain hydrogen halide, is not required to be separated and purified in post processes, and can be suitably used as a film, a varnish, or a molding material; raw material salt of polyamide-imide and production method thereof. The polyamide-imide has a repeating unit represented by the general formula (1): in which R, Rrepresent independently a divalent residue having an aromatic ring, an aliphatic ring or an aliphatic hydrocarbon; R, Rrepresent independently a trivalent residue having an aromatic ring or an aliphatic ring; and an hydrogen atom bonding to the respective rings may be replaced by another atom or an atomic group.

Polyamide-imide, raw material salt of polyamide-imide, and production method thereof

An object of the present invention is to provide an industrially advantageous method for producing a bisimide dicarboxylic acid, which uses substantially no solvent and requires no granulation after completion of the reaction. The above object can be achieved by a method for producing a bisimide dicarboxylic acid with a tricarboxylic acid anhydride and a diamine, including the following processes (i) and (ii):

Method for producing bisimide dicarboxylic acid

An object of the present invention, which was made to solve the problems above, is to provide a polyimide precursor resin composition superior in transparency allowing reduction of the residual volatile material rate during molding and giving a polyimide resin composition (e.g., polyimide film) superior in mechanical properties and transparency even when a cheaper polyamide-imide is used. The present invention relates to a polyimide precursor resin composition, comprising a polyamide-imide (A) containing a diamine monomer unit represented by the following formula (1) and a polyamic acid (B) containing at least one kind of monomer unit selected tetracarboxylic acid monomer units represented by the following formulae (2p) to (2r), wherein the haze of the film having a thickness of 40 &#x3bc;m obtained by imidation of the polyimide precursor resin composition is 4% or less: (wherein, R represents an alkylene group having 1 to 5 carbon atoms); 

Polyimide resin composition, polyimide precursor resin composition for the same, production method thereof, and polyimide film and production method thereof

The present invention provides a substrate for a flexible printed wiring board including an adhesive layer containing an epoxy resin composition, insulating layers respectively stacked on both sides of the adhesive layer and formed with a pair of films containing a nonthermoplastic polyimide resin, and conductor layers respectively disposed on the outer surfaces of the films. The total thickness of the insulating layers respectively stacked on both sides of the adhesive layer is 10 to 100 &#x3bc;m and 2 to 10 times the thickness of the adhesive layer. The mutual adhesion strength between the insulating layers through the intermediary of the adhesive layer is 7.0 N/cm or more.

Substrate for flexible printed wiring board and method for manufacturing the same

A method for preparing a substrate for a flexible print wiring board having a polyimide based resin layer wherein a solution of a polyimide based resin precursor is directly applied on an electrically conducting material to form a polyimide based resin precursor layer and then the precursor layer is cured by heating to prepare a polyimide based resin layer, characterized in that a solution of a polyimide based resin precursor B, which is one of solutions of two types of polyimide based resin precursors, is directly applied on an electrically conducting material and then, on the resultant layer is applied a solution of a polyimide based resin precursor A which allows resolving the residual strain generated in the polyimide based resin formed by the curing of the above polyimide based resin precursor B.

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Uji, Japan

Akira Shigeta