In one embodiment, a filament can comprise a thermoplastic polyimide, wherein the filament is adapted for use in a fused filament fabrication process and the thermoplastic polyimide may have a glass transition temperature not greater than 215° C. Three-dimensional bodies can be printed with the filament, wherein the three-dimensional bodies can have high strength values with even mechanical properties in printing direction and orthogonal to the printing direction.

An embodiment can provide a polyamide-imide film, which has particular punching properties, is colorless and transparent and has excellent mechanical properties and optical properties, and a method for preparing same. The polyamide-imide film comprises a polyamide-imide polymer, which is formed by means of polymerizing an aromatic diamine compound, an aromatic dianhydride compound and a dicarbonyl compound, and satisfies the condition of general formula (1) below. General formula (1) 4≤X/Y≤12 X: the maximum hole diameter (mm) comprising cracks when the film is punched at 10 mm/min using a 2.5 mm spherical tip by means of a UTM compression mode Y: the modulus (GPa) of the film.

A polymer being a product of reactants including a diamine and a monomer represented by Chemical Formula 1: ##STR00001##
wherein, in Chemical Formula 1, R.sup.1, R.sup.2, o, p, L.sup.1, A.sup.1, R.sup.a, m, and n are the same as defined in the detailed description.

A polyimide copolymer according to an embodiment of the present disclosure includes a plurality of structural units. The plurality of structural units include a structural unit derived from dianhydride having an alicyclic structure and a structural unit derived from aromatic diamine including an ether group, thereby mechanical properties, thermal stability and optical characteristics of the polyimide film may be improved.

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.

Provided is a layered product that uses a high temperature-resistant transparent film having sufficient heat resistance, and that is capable of being mechanically released from an inorganic substrate after various processes are performed on the inorganic substrate since the adhesive strength between the high temperature-resistant transparent film and the inorganic substrate is appropriately weak, and that is less warped along with the inorganic substrate. In this layered product, no adhesive is used between the high temperature-resistant transparent film and the inorganic substrate, the release strength between the high temperature-resistant transparent film and the inorganic substrate is at most 0.3 N/cm, and the warpage amount of the layered product when heated at 300° C. is at most 400 .Math.m.

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.

The present disclosure is directed to systems and methods for providing a dielectric layer on a semiconductor substrate capable of supporting very high density interconnects (i.e., ≥100 IO/mm). The dielectric layer includes a maleimide polymer in which a thiol-terminated functional group crosslinks with an epoxy resin. The resultant dielectric material provides a dielectric constant of less than 3 and a dissipation factor of less than 0.001. Additionally, the thiol functional group forms coordination complexes with noble metals present in the conductive structures, thus by controlling the stoichiometry of epoxy to polyimide, the thiol-polyimide may beneficially provide an adhesion enhancer between the dielectric and noble metal conductive structures.

To provide an optical film having excellent visibility in the wide angle direction. An optical film including at least one resin selected from the group consisting of a polyimide-based resin and a polyamide-based resin, wherein the optical film satisfies Formula (1):
0≤Ts≤0.35  (1)
wherein Ts represents a scattered light ratio (%) and is defined as Ts=Td/Tt×100, Td and Tt represent a diffuse light transmittance (%) and a total light transmittance (%), measured in accordance with JIS K-7136, respectively.

An embodiment relates to a polyimide based film for a cover window that may satisfy required performance of an advanced cover window, and a use thereof, and the polyimide based film for a cover window according to the embodiment has excellent visibility without optical stains without deterioration in colorless and transparent optical physical properties, and excellent heat resistance and mechanical physical properties, and thus, may be usefully used for optical applications or the purpose of replacing existing tempered glass. In addition, the polyimide based film for a cover window according to an embodiment may be usefully used in a multilayer structure and a display device.