The invention generally relates to polymer nanocomposite films that possess shape memory properties at elevated temperatures. Such films can absorb microwaves, are thermally conductive, are electrically conductive and have increased mechanical strength. In addition, the present invention relates to methods of fabricating such films into 3D objects. Due to the improved properties of such films more advanced sensors and microwave shields can be constructed.

The present invention provides a multilayer body of an inorganic substrate and a highly heat-resistant transparent film which has sufficient heat resistance and is able to be mechanically separated from the inorganic substrate after being subjected to various processes on the inorganic substrate since the adhesion between the highly heat-resistant transparent film and the inorganic substance is adequately weak. A multilayer body of a highly heat-resistant transparent film and an inorganic substrate, wherein: an adhesive is not substantially used; the peel strength between the highly heat-resistant transparent film and the inorganic substrate is 0.3 N/cm or less; and the CTE of the highly heat-resistant transparent film is 50 ppm/K or less.

The present invention discloses a novel diamine that has a structure bearing an intramolecular imide group and additionally an amide-substituted aromatic ring group at opposite sides of the imide group. The use of the novel diamine as a polymerization ingredient in polyimide production can provide a polyimide film which has remarkably improved mechanical and thermal properties while maintaining optical properties.

A polyamic acid according to an embodiment is formed by a polymerization reaction of a dianhydride compound, a first diamine compound represented by the following Formula 1, and a second diamine compound, which is different from the first diamine compound. A polyimide film derived from the polyamic acid may exhibit excellent heat resistance and improved optical properties: ##STR00001##

Phenolic-terminated and phenolic pendent curable polyimides with very good dielectric properties have been prepared. These materials in combination with epoxy resins and other co-curable resins are ideal for being transformed into flexible films that are ready to be laminated for example between copper foils for applications such as copper-clad laminates for a variety of electronics applications.

A simplified method for removing foreign matters formed on a substrate in a semiconductor device manufacturing process; and a composition for forming a coating film for foreign matter removal use, which can be used in the method. A coating film is formed on a semiconductor substrate using a composition preferably containing a polyamic acid produced from (a) a tetracarboxylic dianhydride compound and (b) a diamine compound having at least one carboxyl group or a polyamic acid produced from (a) a tetracarboxylic dianhydride compound, (b) a diamine compound having at least one carboxyl group and (c) a diamine compound, and then foreign matters occurring on the coating film are removed together with the coating film by the treatment with a developing solution.

The present disclosure relates to a polyimide-based polymer film comprising a polyimide-based polymer containing a polyimide repeating unit synthesized by the reaction of an acid anhydride compound having a specific structure and a diamine compound, wherein a glass transition temperature is 400° C. or more, and a thickness direction retardation value at a thickness of 10 μm is 150 nm or less, and a substrate for a display device and an optical device using the same.

A laminate includes a glass base, a silicone resin layer, and a polyimide resin layer. The polyimide resin layer includes a fluorine-atom-containing polyimide. When examined by infrared absorption, the polyimide resin layer gives a spectrum in which a ratio of an area of a peak appearing at 3,150 cm.sup.-1 to 3,750 cm.sup.-1 to an area of a peak appearing at 1,650 cm.sup.-1 to 1,750 cm.sup.-1 is 0.9 or less.

A polyimide-polybenzoxazole precursor solution, a polyimide-polybenzoxazole film, and a method of manufacturing the film are disclosed. A polyimide-polybenzoxazole film manufactured using the polyimide-polybenzoxazole precursor solution is formed by copolymerizing a unit structure of diamine and dianhydride and a unit structure of diaminophenol and dicarbonyl chloride in an organic solvent. The film is colorless and transparent, like conventional polyimide films, and can exhibit improved heat resistance and low birefringence.

A polyimide composite material, a manufacturing method thereof, and a display substrate are provided. Inorganic nanoparticles are connected with polyimide structural units by chemical bonds, thus enhancing compatibility of the inorganic nanoparticles and the polyimide structural units. Moreover, because of an enhancement effect of the inorganic nanoparticles, a mechanical property and thermal stability of the polyimide composite material may be effectively improved.