Abstract: A polyimide precursor including at least one repeating unit represented by the following chemical formula (1): in which A is an arylene group; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, and a polyimide obtained from the polyimide precursor has a coefficient of linear thermal expansion from 50° C. to 400° C. of 100 ppm/K or less.

Abstract: A polyimide precursor comprising a repeating unit represented by the following chemical formula (1): in which A is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, wherein the polyimide precursor comprises at least one type of repeating unit represented by the chemical formula (1) in which A is a group represented by chemical formula (2) or (3): in which m independently represents 0 to 3 and n independently represents 0 to 3; Y1, Y2 and Y3 each independently represent at least one selected from the group consisting of hydrogen atom, methyl group and trifluoromethyl group; and Q and R each independently represent direct bond, or at least one of —NHCO—, —CONH—, —COO— and —OCO—, in which Z and W each independently represent a divalent aromatic group having 6 to 18 carbon atoms; and Y4 rep

Abstract: A polyimide precursor composition including a polyimide precursor, and a fine particle having an optical anisotropy; and a polyimide composition including a polyimide, and a fine particle having an optical anisotropy.

Abstract: The present invention relates to a polyimide film consisting essentially of a polyimide comprising a repeating unit represented by the following chemical formula (1): wherein the film has a YI (yellowness index) of 4 or less, a tensile modulus of elasticity of 4 GPa or more, and a load at break of 10 N or more.

Abstract: The present invention relates to a polyimide precursor comprising a repeating unit represented by the following chemical formula (1A) and a repeating unit represented by the following chemical formula (2A): wherein A1 is a divalent group having an aromatic ring; and R1 and R2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, wherein A2 is a divalent group having an aromatic ring; and R3 and R4 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

Abstract: A polyimide precursor comprising at least one repeating unit represented by the following chemical formula (5): in which A3 is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X3 and Y3 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, and/or at least one repeating unit represented by the following chemical formula (6): in which A3 is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X4 and Y4 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

Abstract: The present invention relates to a polyimide precursor comprising a repeating unit represented by the following chemical formula (1): wherein A is a tetravalent group having at least one aliphatic six membered ring and no aromatic ring in the chemical structure, and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the following chemical formula (2) in the chemical structure: and X1 and X2 are each independently hydrogen, a C1-6 alkyl group or a C3-9 alkylsilyl group.

Abstract: A polyimide precursor obtained from a tetracarboxylic acid component including norbornane-2-spiro-?-cyclopentanone-??-spiro-2?-norbornane-5,5?,6,6?-tetracarboxylic dianhydride, or a derivative thereof, and a diamine component including a diamine, or a derivative thereof, the norbornane-2-spiro-?-cyclopentanone-??-spiro-2?-norbornane-5,5?,6,6?-tetracarboxylic dianhydride characterized in that the ratio of the peak area of a certain peak is 60% or more in a gas chromatogram obtained by conducting gas chromatography analysis.

Abstract: A polyimide precursor consisting of a repeating unit represented by the following chemical formula (1): and a repeating unit represented by the following chemical formula (2): in which A is a tetravalent group of a tetracarboxylic acid, from which carboxyl groups have been removed; B is a divalent group of a diamine, from which amino groups have been removed; with the proviso that the A group and the B group contained in each repeating unit may be the same as, or different from each other; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, the amount of the repeating unit represented by the chemical formula (2) is 30 mol % or more and 90 mol % or less relative to the total repeating units, 50 mol % or more of the total amount of the B group in the chemical formula (1) and the chemical formula (2) is p-phenylene group and/or a specific divalent group containing two or more benzene rings, the polyimide pr

Abstract: The present invention relates to a polyimide precursor comprising a repeating unit represented by the following chemical formula (1): wherein A is a tetravalent group having at least one aliphatic six membered ring and no aromatic ring in the chemical structure, and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the following chemical formula (2) in the chemical structure: and X1 and X2 are each independently hydrogen, a C1-6 alkyl group or a C3-9 alkylsilyl group.

Abstract: A polyimide precursor comprising a repeating unit represented by the following chemical formula (1): in which A is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, wherein the polyimide precursor comprises at least one type of repeating unit represented by the chemical formula (1) in which A is a group represented by chemical formula (2) or (3): in which m independently represents 0 to 3 and n independently represents 0 to 3; Y1, Y2 and Y3 each independently represent at least one selected from the group consisting of hydrogen atom, methyl group and trifluoromethyl group; and Q and R each independently represent direct bond, or at least one of —NHCO—, —CONH—, —COO— and —OCO—, in which Z and W each independently represent a divalent aromatic group having 6 to 18 carbon atoms; and Y4 repre

Abstract: A polyimide precursor comprising at least one repeating unit represented by the following chemical formula (5): in which A3 is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X3 and Y3 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, and/or at least one repeating unit represented by the following chemical formula (6): in which A3 is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X4 and Y4 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

Abstract: A polyimide comprising a repeating unit represented by the following chemical formula in which A is a divalent group of an aromatic diamine or an aliphatic diamine, from which amino groups have been removed; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, wherein the polyimide precursor comprises at least two types of repeating units represented by the chemical formula (1) in which A is a group represented by any one of the following chemical formulas (2-1), (2-2), (3) and (4): in which a polyimide obtained from the polyimide precursor has a coefficient of linear thermal expansion from 50° C. to 200° C. of 50 ppm/K or less and a transmittance at 400 nm of 75% or more in the form of a polyimide film having a thickness of 10 ?m.

Abstract: A polyimide precursor including at least one repeating unit represented by the following chemical formula (1): in which A is an arylene group; and X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms, and a polyimide obtained from the polyimide precursor has a coefficient of linear thermal expansion from 50° C. to 400° C. of 100 ppm/K or less.

Abstract: A polyimide precursor comprising a repeating unit represented by the following chemical formula (1): in which A is a tetravalent group having at least one aliphatic six-membered ring and no aromatic ring in the chemical structure, and B is a divalent group having at least one amide bond and an aromatic ring in the chemical structure; or A is an aliphatic tetravalent group and B is a divalent group having at least one chemical structure represented by the following chemical formula (2) in the chemical structure: and X1 and X2 are each independently hydrogen, a C1-6 alkyl group or a C3-9 alkylsilyl group.

Abstract: Disclosed is a novel co-polyimide precursor for producing a polyimide having high transparency.

Abstract: A flexible wiring board for a tape carrier package with reduced tackiness and a tape carrier package formed by using the flexible wiring board is disclosed. The flexible wiring board for a tape carrier package has an insulating film 1, a wiring pattern 3 formed on a surface of the insulating film, and an overcoat layer 9 containing a resin cured material and a porous fine particle, and protecting at least a region of said wiring pattern.

Abstract: A polyimide film having enhanced surface activity and improved surface adhesion, and a polyimide film having a metal film in which the metal film is bonded to the polyimide film with practically accepted high bonding strength are provided by a polyimide film having, at least on one surface, a coated particle layer comprising inorganic particles having a mean particle size of 1,000 nm or less which are coated with a metal oxide layer via an intervening layer comprising a mixture of the same metal oxide as above and polyimide, and the polyimide film having a metal film placed on the coated particle layer.

Abstract: A polyimide complex sheet is composed of an aromatic polyimide film, an intervening layer and a thin metal oxide layer in which the intervening layer is formed of a mixture of the metal oxide and the aromatic polyimide under such condition that a ratio of the metal oxide to the aromatic polyimide increases from a side facing the polyimide film to a side facing the metal oxide layer and the intervening layer is united to the polyimide film and the metal oxide layer under such condition that the metal oxide layer is not peelable from the polyimide film without breakage of the metal oxide layer.

Abstract: An improved injection blow molding machine has an melt accumulator or melt metering chamber and a vertically extending oval type die communicating therewith for injecting an elliptical annular parison through the die, which is to be blow molded to produce a hollow double wall type article. The oval type die includes a die housing and a mandrel mounted therein to define a melt passage therebetween having a die lip or opening of a four sided elliptical annular profile at a free lower end of the die. The accumulator is in direct contact with the mandrel, and/or the die housing is enlarged in a horizontal direction at a lower end portion thereof. Preferably the enlarged lower end portion is formed by a plate part fixed to a block part forming an upper portion of the die housing.