Provided are a polyimide-based film, a window cover film, and a display device including the same. More specifically, a polyimide-based film having different surface energies from each other on both surfaces, a window cover film having excellent optical properties such as a visibility, and a display panel including the same are provided.

The present invention relates to a cross-linking agent compound of which end functional group is substituted with a protection group of a specific structure, a liquid crystal alignment composition comprising the cross-linking agent compound and polymer containing repeat units of polyimide or a precursor thereof, a method of preparing liquid crystal alignment film, a liquid crystal alignment film, and a liquid crystal display using the same.

The present invention relates to a polyimide-based film, a window cover film, and a display panel including the same. More specifically, the present invention relates to a polyimide-based film having a difference (ΔI) between the maximum and minimum values of intensity in a thickness direction of 0.6 or less, when an aromatic ring peak of 1610 to 1630 cm.sup.−1 was measured by Raman spectroscopy in which an excitation wavelength is 532 nm, a laser spot is 1 to 2 μm, and a thickness direction measurement interval is 1 μm.

An LED filament and an LED light bulb applying the same are provided. The LED filament includes a at least one LED section, wherein the at least one LED section comprises at least two LED chips electrically connected to each other through a first wire, and at least two conductive electrodes, wherein each of the at least two conductive electrodes is electrically connected to corresponding one of the at least one LED section; and a light conversion layer, covering the at least one LED section and a portion of each of the at least two conductive electrodes, a portion of the first wire is exposed outside the light conversion layer.

Provided is a porous polyimide composition having low colorability and high light transmittability. Provided is a porous polyimide composition, in which an average pore size (L) obtained by the following expression based on a pore volume (V) and a BET specific surface area (A) determined by a gas adsorption method: L = 4V/A; is 5 nm or more and 500 nm or less, a light transmittance at 450 nm at a film thickness of 1 mm is 10% or more and 100% or less, and a degree of polymerization (n) is 5 or more and less than 40. [Selected Drawing] None

The present invention relates to a polyimide-based film, a window cover film, and a display panel including the same. More specifically, the present invention relates to a polyimide-based film having a difference (ΔI) between the maximum and minimum values of intensity in a thickness direction of 0.6 or less, when an aromatic ring peak of 1610 to 1630 cm.sup.−1 was measured by Raman spectroscopy in which an excitation wavelength is 532 nm, a laser spot is 1 to 2 μm, and a thickness direction measurement interval is 1 μm.

The present invention relates to a crosslinking agent compound in which a terminal crosslinkable functional group is capped with a silane-based protecting group, a photosensitive composition including the same, and a photosensitive material using the same.

A polyimide precursor composition according to an exemplary embodiment includes an imide precursor having an organic group derived from a cyclic ether group-containing compound. A polyimide film formed using the polyimide precursor composition has improved heat resistance and mechanical properties, and has high absorbance in a wavelength range in an ultraviolet region.

A method of manufacturing a bump structure includes forming a passivation layer over a substrate. A metal pad structure is formed over the substrate, wherein the passivation layer surrounds the metal pad structure. A polyimide layer including a polyimide is formed over the passivation layer and the metal pad structure. A metal bump is formed over the metal pad structure and the polyimide layer. The polyimide is a reaction product of a dianhydride and a diamine, wherein at least one of the dianhydride and the diamine comprises one selected from the group consisting of a cycloalkane, a fused ring, a bicycloalkane, a tricycloalkane, a bicycloalkene, a tricycloalkene, a spiroalkane, and a heterocyclic ring.

Disclosed herein is a high thermal resistant polyolefin-based separator including a coating layer containing polyamic acid. Specifically, the separator includes a polyolefin-based substrate film, and a coating layer containing polyamic acid formed on one or both surfaces of the polyolefin-based substrate film, wherein the polyamic acid contains one or more functional groups selected from the group consisting of a sulfone group, a trifluoromethyl group, an alkyl group, and a phenyl ether group. Also, disclosed herein is an electrochemical battery having improved thermal stability by using the separator including a coating layer containing polyamic acid.