NOVELTY - A biaxially-stretched nylon coating film comprises a coating layer having thickness of 0.01-2 mu m on a biaxially-stretched nylon film (3) containing nylon resin as a raw material. The maximum refractive index value (Nx) of biaxially-stretched nylon-film surface, minimum refractive index value (Ny) of biaxially-stretched nylon-film surface, refractive index value (Nz) in the thickness direction of the biaxially-stretched nylon film, and degree of plane orientation (P) satisfy a specific relation.    USE - Biaxially-stretched nylon coating film is used for forming laminate film for cold molding and lamination wrapping material, and as cladding material of battery (all claimed). Uses include but are not limited to electric vehicle, tablet-type terminal device, smartphone, packaging for pharmaceuticals and foodstuffs, and refill wrapping material for liquid detergents.    ADVANTAGE - The biaxially-stretched nylon coating film has excellent deep-drawing moldability during cold molding.    DETAILED DESCRIPTION - A biaxially-stretched nylon coating film comprises a coating layer having thickness of 0.01-2 mu m on a biaxially-stretched nylon film containing nylon resin as a raw material. The maximum refractive index value (Nx) of biaxially-stretched nylon-film surface, minimum refractive index value (Ny) of biaxially-stretched nylon-film surface, refractive index value (Nz) in the thickness direction of the biaxially-stretched nylon film, and degree of plane orientation (P) satisfy the relation: P=(Nx+Ny)/2-Nz greater than or equal to 0.042. INDEPENDENT CLAIMS are included for the following:    (1) laminate film, which is obtained by laminating the biaxially-stretched nylon film; and    (2) manufacture of biaxially-stretched nylon coating film, which involves molding raw film from the raw material, biaxially stretching the raw film by tubular-type biaxially-stretching, heat-processing and heat-setting the film, and coating a sliding agent to the surface of the film.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the apparatus for manufacturing biaxially-stretched nylon film.    Biaxially-stretched nylon film (3)    Tubular stretching apparatus (10)    Extruder (91)    Circular dice (92)    Water-cooling ring (93)