The present invention relates to polyetherimide polymers which can for example be used in lithographic processes for the photofabrication of three-dimensional (3D) articles. The invention further relates to compositions including these polyetherimide polymers. Still further, the invention relates to lithographic methods to form 3D articles or objects that incorporate the aforementioned polymer compositions.

A liquid crystal light control element that controls a light absorption state by voltage application, the liquid crystal light control element including: a liquid crystal layer containing a liquid crystal composition between a pair of substrates each having an electrode; and a liquid crystal alignment film that is provided on at least one of the substrates and aligns a liquid crystal vertically, wherein the liquid crystal composition contains a liquid crystal and a dichroic dye, the liquid crystal alignment film is obtained from a liquid crystal aligning agent containing a polyimide precursor in which a diamine having a specific side chain is used as a part of the raw material or a polyimide obtained by imidizing the polyimide precursor, and the proportion of the diamine used is 50 to 100 mol % based on the entire diamine component.

The present disclosure relates to a polyimide precursor and flexible polyimide obtained by imidization of the polyimide precursor and having high transparency, high glass transition temperature and low coefficient of thermal expansion.

A polyimide film contains fluorinated substituents and cardo structures. The polyimide film exhibits excellent heat-resistance, transparency and mechanical properties. The polyimide film has a glass-transition temperature (Tg) of at least 360° C., a coefficient of thermal expansion (CTE) of 50 ppm/° C. or lower, a modulus of at least 4.0 Gpa, a b* value of 5 or lower and yellowness index of 8 or less. The polyimide film can be used as a display substrate or an optical film in a liquid crystal display (LCD), an organic light-emitting diode (OLED) and in other fields where the characteristic features are required.

A polyimide copolymer according to the present invention has a particular structure in which siloxane structures are distributed in a nanosize in a polymer and thus enables excellent transparency, heat resistance, mechanical strength and flexibility and effective reduction of residual stress, and thus can be used in various fields such as a substrate for a device, a cover substrate for a display, an optical film, an integrated circuit (IC) package, an adhesive film, a multi-layer flexible printed circuit (FPC), tape, a touch panel and a protective film for an optical disk.

A solar cell including a semiconductor substrate having a first conductivity type an emitter region, having a second conductivity type opposite to the first conductivity type, on a first main surface of the semiconductor substrate an emitter electrode which is in contact with the emitter region a base region having the first conductivity type a base electrode which is in contact with the base region and an insulator film for preventing an electrical short-circuit between the emitter region and the base region, wherein the insulator film is made of a polyimide, and the insulator film has a C.sub.6H.sub.11O.sub.2 detection count number of 100 or less when the insulator film is irradiated with Bi.sub.5.sup.++ ions with an acceleration voltage of 30 kV and an ion current of 0.2 pA by a TOF-SIMS method. The solar cell can have excellent weather resistance and high photoelectric conversion characteristics.

A polyimide luminescent material, a preparation method, and a used thereof are disclosed; the polyimide luminescent material includes a polyimide resin and a rare earth complex distributed in the polyimide resin, wherein the polyimide resin is a condensation polymer of an aromatic diamine containing a bidentate chelate ligand and an aromatic dianhydride, and the rare earth complex and the bidentate chelate ligand are connected by a chemical bond. The luminescent material has enhanced fluorescence intensity, thermal stability, and mechanical properties. The preparation method is simple and easy, and is suitable for industrial production.

Provided are a composition for forming a polyimide film for a cover window which may satisfy performance required for an advanced cover window, a method for preparing the same, and a use thereof. According to an implementation, a polyimide film for a cover window, which has excellent visibility without optical stain while colorless and transparent optical properties were not deteriorated and has excellent heat resistance and mechanical properties, and thus, is for use in optical applications, may be provided. In addition, a polyimide film for a cover window according to an implementation may be useful in various display devices.

Provided are a composition for forming a polyimide film, a method for preparing the same, and a use thereof. According to an implementation, a polyimide film which has excellent heat resistance, is flexible, and has excellent bending properties, without deteriorating colorless and transparent optical properties may be provided. In addition, the polyimide film according to an implementation may be useful for various flexible display devices.

The present invention provides an electrochromic polyamic acid material, a preparation method thereof and a display device, wherein the molecular structure of the electrochromic polyamic acid material includes oligoaniline and carbazolyl triphenylamine. The oligoaniline serves as an electrochemically sensitive group, and the carbazolyl triphenylamine serves as a fluorescence emitting group. The electrochromic polyamic acid material is an electrically controlled fluorescent polymer. Fluorescence intensity of the electrochromic polyamic acid material undergoes reversible fluorescence conversion with a change of an applied voltage, due to a redox reaction of the oligoaniline at different voltages, resulting in an interchange between a benzene ring and an anthracene ring in a molecular structure, and an electron/energy transfer path with the fluorescence emitting group are generated or eliminated, thereby realizing the electrically controlled fluorescent properties of the electrochromic polyamic acid material.