In a first aspect, a polyimide film includes a polyimide derived from a dianhydride and a diamine. The dianhydride, the diamine or both the dianhydride and the diamine include an alicyclic monomer, an aliphatic monomer or both an alicyclic monomer and an aliphatic monomer. The polyimide film has an L* of at least 90, a b* of 1.25 or less, a yellowness index of 2.25 or less and a haze of less than 1% for a film thickness of 50 μm. In a second aspect, an electronic device includes the polyimide film of the first aspect.

A polyimide and a method for manufacturing the polyimide are provided. The method for manufacturing the polyimide includes: mixing a diamine compound with a substance and an organic solvent, wherein the diamine compound includes an amide bond, and a molecular structure of the substance includes an ether dianhydride; and forming the polyimide by a cross-linking and curing process. A regular molecular chain arrangement, wherein the regular molecular chain arrangement has highly oriented in-plane crystallization and low free volume; a simple rigid planar structure; and intramolecular hydrogen bonds are introduced to prepare the polyimide that has high barrier performance, excellent heat resistance, and a low thermal expansion coefficient.

Provided are a polyamic acid solution that can be formed into a film without peeling even when the film is thick and can be stably stored at room temperature, and a laminate that can be suitably used for production of a flexible device. In the alkoxysilane-modified polyamic acid solution according to the present invention, an additive amount of an alkoxysilane compound that contains an amino group is more than 0.050 parts by weight and less than 0.100 parts by weight.

The present application relates to a polyamic acid composition, a method for preparing the polyamic acid composition, a polyimide comprising the same, and a coating material comprising the same, which provides a polyamic acid composition capable of implementing a low permittivity and heat resistance, and insulation properties and mechanical properties in a harsh condition such as a high temperature simultaneously, a method for preparing the polyamic acid composition, a polyimide comprising the same and a coating material comprising the same.

A method for coating a glass article includes obtaining a glass article; selecting a coating including a fluorinated polyimide, and coating the glass article with the selected coating including the fluorinated polyimide. The fluorinated polyimide having a cohesive energy density less than or equal to 300 KJ/mol, and a glass transition temperature (T.sub.g) less than or equal to 625 K.

A dual-cure method for forming a solid polymeric structure is provided. An end-capped, imide-terminated prepolymer is combined with at least one photopolymerizable olefinic monomer, at least one photoinitiator, and a diamine, to form a curable resin composition, which, in a first step, is irradiated under conditions effective to polymerize the at least one olefinic monomer, thus forming a scaffold composed of the prepolymer and the polyolefin with the diamine trapped therein. The irradiated composition is then thermally treated at a temperature effective to cause a transimidization reaction to occur between the prepolymer and the diamine, thereby releasing the end caps of the prepolymer and providing the solid polymeric structure. A curable resin composition comprising an end-capped, imide-terminated prepolymer, at least one photopolymerizable olefinic monomer, at least one photoinitiator, and a diamine, is also provided, as are related methods of use.

Provided are a polyimide film, preparation method, and application thereof. The polyimide film is a colorless transparent film with low thermal expansion. The polyimide film is obtained by taking a mixture of rigid aromatic diamine and fluorine-containing aromatic diamine, a mixture of rigid aromatic tetracarboxylic dianhydride and fluorine-containing aromatic tetracarboxylic dianhydride as raw materials, mixing the raw materials to obtain a resin solution, and then conducting imidizing and post-treating. The polyimide film not only has excellent transparency, but also has the advantages of low thermal expansion, high modulus, high glass transition temperature, and so on, and can be well applied to a flexible optoelectronic display substrate, a flexible printed circuit board, or an electronic packaging substrate.

A transparent polyimide mixture is disclosed. The transparent polyimide mixture includes a transparent polyimide, an additive, and a solvent. A molecular chain of the transparent polyimide includes an active hydrogen atom. The additive includes a carbodiimide group. An equivalent ratio of the active hydrogen atom and the carbodiimide group is in a range of 1:0.8 to 1:1.2. A method for preparing the transparent polyimide mixture, a transparent polyimide film, and a method for preparing a transparent polyimide film are also disclosed.

A polyimide precursor solution contains a polyimide precursor, wherein in the case where the polyimide precursor is analyzed by gel permeation chromatography, the elution curve of the polyimide precursor has a region A including a higher-molecular-weight peak and a region B including a lower-molecular-weight peak; a weight average molecular weight determined from the region A in terms of polystyrene is approximately 10,000 or more, and a weight average molecular weight determined from the region B in terms of polystyrene is approximately less than 10,000; and when the area of the region A is a and the area of the region B is b, the polyimide precursor satisfies Equation (1)
a/(a+b)=approximately from 0.70 to 0.98.  Equation 1:

A method for manufacturing a thick polyimide film includes providing a first and second laminated structures. The first and second laminated structures are heated, and the heated first and second laminated structures are wound together to form a third laminated structure. The first polyamic acid gel film of the heated first laminated structure and the second polyamic acid gel film of the heated second laminated structure are overlapped and bonded together to form a third polyamic acid gel film. Two third laminated structures are wound together to form a fourth polyamic acid gel film. A dehydration ring-closure imidization reaction is applied to the fourth polyamic acid gel film by heating to obtain the thick polyimide film. A thick polyimide film manufactured by the method is also disclosed.