Abstract: 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. <1> A method for producing purified MI, comprising reducing an acid value of crude MI by 50% or more, by adding carbodiimide (CDI) to a solution comprising the crude MI to react an acid component in the crude MI with the CDI. <2> The method for producing purified MI, comprising adding 0.5% by mass or more and 8% by mass or less of the CDI with respect to a mass of the crude MI for reaction. <3> The method for producing purified MI, wherein the CDI is N,N?-diisopropyl carbodiimide (DIC). <4> The method for producing purified MI, comprising removing a urea derivative of the CDI (CDI-U) by-produced when reacting the acid component in the crude MI with the CDI.

Abstract: 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: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In 1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less.

Abstract: 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. <1> A method for producing purified MI, comprising reducing an acid value of crude MI by 50% or more, by adding carbodiimide (CDI) to a solution comprising the crude MI to react an acid component in the crude MI with the CDI. <2> The method for producing purified MI, comprising adding 0.5% by mass or more and 8% by mass or less of the CDI with respect to a mass of the crude MI for reaction. <3> The method for producing purified MI, wherein the CDI is N,N?-diisopropyl carbodiimide (DIC). <4> The method for producing purified MI, comprising removing a urea derivative of the CDI (CDI-U) by-produced when reacting the acid component in the crude MI with the CDI.

Abstract: 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. <1> A method for producing purified MI, comprising reducing an acid value of crude MI by 50% or more, by adding carbodiimide (CDI) to a solution comprising the crude MI to react an acid component in the crude MI with the CDI. <2> The method for producing purified MI, comprising adding 0.5% by mass or more and 8% by mass or less of the CDI with respect to a mass of the crude MI for reaction. <3> The method for producing purified MI, wherein the CDI is N,N?-diisopropyl carbodiimide (DIC). <4> The method for producing purified MI, comprising removing a urea derivative of the CDI (CDI-U) by-produced when reacting the acid component in the crude MI with the CDI.

Abstract: 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: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In 1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less.

Abstract: 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: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In 1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less.

Abstract: An object of the present invention is to provide a bismaleimide using an aliphatic diamine, in which acid components remaining as an impurity at a very small amount in the bismaleimide have been effectively removed, that is, a bismaleimide using an aliphatic diamine, an acid value of which has sufficiently been reduced, and a method for producing it. There are provided a bismaleimide using an aliphatic diamine as a diamine component, characterized in that an acid value thereof is 2 mg-KOH/g or less, and a method for producing the bismaleimide, comprising adding carbodiimide to a solution comprising a crude bismaleimide having an acid value of more than 2 mg-KOH/g, and reacting acid components in the crude bismaleimide with carbodiimide.

Abstract: 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. <1> A method for producing purified MI, comprising reducing an acid value of crude MI by 50% or more, by adding carbodiimide (CDI) to a solution comprising the crude MI to react an acid component in the crude MI with the CDI. <2> The method for producing purified MI, comprising adding 0.5% by mass or more and 8% by mass or less of the CDI with respect to a mass of the crude MI for reaction. <3> The method for producing purified MI, wherein the CDI is N,N?-diisopropyl carbodiimide (DIC). <4> The method for producing purified MI, comprising removing a urea derivative of the CDI (CDI-U) by-produced when reacting the acid component in the crude MI with the CDI.

Abstract: 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: <1> A bismaleimide (D-BMI) modified product in which an amino group of dimer diamine is maleimidized, the bismaleimide modified product having the following characteristics: 1) An acid value of the D-BMI modified product is 2 mg-KOH/g or less. 2) In 1H-NMR, when quantitative comparison is performed using an integrated value (A) of a peak corresponding to a proton of a methylene group directly bound to a nitrogen atom of a maleimide group and an integrated value (B) of a peak corresponding to a vinyl proton of a maleimide group, A/B is 1.25 or more and 2.00 or less.

Abstract: An object of the present invention is to provide a bismaleimide using an aliphatic diamine, in which acid components remaining as an impurity at a very small amount in the bismaleimide have been effectively removed, that is, a bismaleimide using an aliphatic diamine, an acid value of which has sufficiently been reduced, and a method for producing it. There are provided a bismaleimide using an aliphatic diamine as a diamine component, characterized in that an acid value thereof is 2 mg-KOH/g or less, and a method for producing the bismaleimide, comprising adding carbodiimide to a solution comprising a crude bismaleimide having an acid value of more than 2 mg-KOH/g, and reacting acid components in the crude bismaleimide with carbodiimide.

Abstract: The present invention provides fibrous copper microparticles suppressed in the occurrence of irregularities on the surface thereof and the aggregates of the fibrous copper microparticles having an average crystallite diameter controlled so as to fall within a specific range. In the fibrous copper microparticles of the present invention, the number of fibrous copper microparticles each including one or more irregularities each having a dimensional difference of 0.02 ?m or more, in a range of 1 ?m in the lengthwise direction of a fibrous body, between the maximum diameter portion of the fibrous body and the minimum diameter portion of the fibrous body falling in a diameter dimension range of 0.01 to 0.5 ?m, and each having a length of 1 ?m or more is 10 or less per 100 of the fibrous copper microparticles.

Abstract: Fibrous copper microparticles having a minor axis of 1 ?m or less and an aspect ratio of 10 or more, wherein the content of the copper particles having a minor axis of 0.3 ?m or more and an aspect ratio of 1.5 or less is 0.1 or less copper particle per one fibrous copper microparticle.

Abstract: The present invention provides coated fibrous copper microparticles, wherein the coated fibrous copper microparticles are fibrous copper microparticles each at least partially coated with a metal other than copper, and the length and the aspect ratio of the fibrous copper microparticles are 1 ?m or more and 10 or more, respectively.

Abstract: 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.

Abstract: 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.

Abstract: A metal conductor layer is provided on at least one surface of a heat resistant base. The heat resistant base is peelable from the metal conductor layer. The heat resistant base is preferably a metal foil or a non-thermoplastic polyimide resin film. The metal conductor layer preferably includes a vapor deposition metal layer and/or a plating metal layer. The metal conductor layer preferably includes a metal layer (I) formed in an interface with the heat resistant base by vapor deposition, and at least one metal layer (II) formed on the metal layer (I) by vapor deposition or electroplating. At least one insulative film layer of a non-thermoplastic polyimide resin may be provided on the metal conductor layer.

Abstract: 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 ?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.

Abstract: There is provided a flexible circuit board 22 that, when deposited on another flexible circuit board 40, causes no gap to occur between wiring films 4a, 4a, of the flexible circuit board 40. Moreover, a plurality of flexible circuit boards are deposited on one another to provide a flexible multi-layer wiring circuit board having no gaps between the flexible circuit boards and having less bowing. In the flexible circuit board 22, the thickness of a bonding layer 16, 16a, on the opposed side of a bowing metallic member 2, of an inter-layer insulating film 10 where which bumps 6 are formed is greater than the thickness of a bonding layer on the side of metallic member 2. When the flexible circuit board 22 is deposited on the other flexible circuit board 40 to form a flexible multi-layer wiring circuit board 50, the bonding layer 16, 16a can be filled between the wiring films 4a, 4a, so that the flexible multi-layer wiring circuit board 50 has no gaps and a less bowing.

Abstract: 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 ?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.

Abstract: 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.