Provided is a polyamideimide film and an image display device including the same and a polyamideimide film which may satisfy a high light transmittance while maintaining mechanical properties to significantly improve viewing properties, and may satisfy all of a low refractive index, a low retardation in the unit thickness direction (R.sub.th), a low yellow index, a low haze, and the like to significantly improve optical properties such as transparency and visibility. An image display device including the same is also provided.

Provided is a polyamideimide film and an image display device including the same and a polyamideimide film which may satisfy a high light transmittance while maintaining mechanical properties to significantly improve viewing properties, and may satisfy all of a low refractive index, a low retardation in the unit thickness direction (R.sub.th), a low yellow index, a low haze, and the like to significantly improve optical properties such as transparency and visibility. An image display device including the same is also provided.

An amide compound and a nitrogen-containing heterocyclic ring-containing compound which have a specific repeating unit and a crosslinking site represented by Formula (2):

—C≡CX.sup.1

at a molecular end.

Provided is a compound that can be used as a base resin for a photosensitive resin composition. The photosensitive resin can form a fine pattern and can achieve high resolution without impairing mechanical strength and solubility. The compound is represented by the general formula (1): ##STR00001##
wherein Z represents a linear, branched or cyclic divalent hydrocarbon group having 2 to 30 carbon atoms; X.sup.1 to X.sup.3 represent any of —CO.sub.2—, —CONR.sup.X1—, —O—, —NR.sup.X1—, —S—, —SO.sub.2—, —SO.sub.3— and —SO.sub.2NR.sup.X1— and may be the same as or different from each other, provided that R.sup.X1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 30 carbon atoms; Ar represents a divalent aromatic group having 2 to 30 carbon atoms; L.sup.1 and L.sup.2 independently represent a divalent hydrocarbon group having 1 to 30 carbon atoms; and x and y are each independently 0 or 1.

Provided is a compound that can be used as a base resin for a photosensitive resin composition. The photosensitive resin can form a fine pattern and can achieve high resolution without impairing mechanical strength and solubility. The compound is represented by the general formula (1): ##STR00001##
wherein Z represents a linear, branched or cyclic divalent hydrocarbon group having 2 to 30 carbon atoms; X.sup.1 to X.sup.3 represent any of —CO.sub.2—, —CONR.sup.X1—, —O—, —NR.sup.X1—, —S—, —SO.sub.2—, —SO.sub.3— and —SO.sub.2NR.sup.X1— and may be the same as or different from each other, provided that R.sup.X1 is a hydrogen atom or a monovalent hydrocarbon group having 1 to 30 carbon atoms; Ar represents a divalent aromatic group having 2 to 30 carbon atoms; L.sup.1 and L.sup.2 independently represent a divalent hydrocarbon group having 1 to 30 carbon atoms; and x and y are each independently 0 or 1.

The embodiments provide a polyamide-imide-based film that comprises a polyamide-imide-based polymer and has an RC value of 0.96 to 1.03 as represented by the following Equation 1, whereby it is uniform in quality and excellent in mechanical properties and optical properties, a process for preparing the same, and a cover window and a display device comprising the same. <Equation 1>RC=CTE.sub.MD/CTE.sub.TD In Equation 1, CTE.sub.MD is an average value of the coefficients of thermal expansion (ppm/° C.) in the MD direction of the film, CTE.sub.TD is an average value of the coefficients of thermal expansion (ppm/° C.) in the TD direction of the film, and the average value is an average of the coefficients of thermal expansion measured at six points in total, in which two arbitrary points are selected in each of region N, region C, and region S partitioned in the TD direction of the film.

The embodiments provide a polyamide-imide-based film that comprises a polyamide-imide-based polymer and has an RC value of 0.96 to 1.03 as represented by the following Equation 1, whereby it is uniform in quality and excellent in mechanical properties and optical properties, a process for preparing the same, and a cover window and a display device comprising the same. <Equation 1>RC=CTE.sub.MD/CTE.sub.TD In Equation 1, CTE.sub.MD is an average value of the coefficients of thermal expansion (ppm/° C.) in the MD direction of the film, CTE.sub.TD is an average value of the coefficients of thermal expansion (ppm/° C.) in the TD direction of the film, and the average value is an average of the coefficients of thermal expansion measured at six points in total, in which two arbitrary points are selected in each of region N, region C, and region S partitioned in the TD direction of the film.

The embodiments provide a polyamide-imide-based film that comprises a polyamide-imide-based polymer and has an rSE value of 0.8 to 1.25 as represented by the following Equation 1, whereby it is excellent in adhesion to a hard coating layer and light resistance to a UV light source, a process for preparing the same, and a composite film and a display device comprising the same. <Equation 1> rSE=SE1/SE2 In Equation 1, SE1 is the surface energy (dyne) of a first side of the film, and SE2 is the surface energy (dyne) of a second side of the film.

The embodiments provide a polyamide-imide-based film that comprises a polyamide-imide-based polymer and has an rSE value of 0.8 to 1.25 as represented by the following Equation 1, whereby it is excellent in adhesion to a hard coating layer and light resistance to a UV light source, a process for preparing the same, and a composite film and a display device comprising the same. <Equation 1> rSE=SE1/SE2 In Equation 1, SE1 is the surface energy (dyne) of a first side of the film, and SE2 is the surface energy (dyne) of a second side of the film.

The present disclosure relates to a polyamideimide film-forming composition, a polyamideimide film, a method of preparing a polyamideimide film-forming composition, a method of producing a polyamideimide film, and uses of a polyamideimide film-forming composition and a polyamideimide film. The polyamideimide film according to one embodiment prevents deterioration of colorless and transparent optical properties, has excellent visibility with no optical stains, has excellent heat resistance, is flexible, and has excellent bending properties.