A method for producing a phase difference film is provided. The phase difference film includes an orientation layer formed of a resin C having a negative intrinsic birefringence value. The resin C contains a block copolymer having a block (A) including as a main component a polymerization unit A having a negative intrinsic birefringence value and a block (B) including as a main component a polymerization unit B, and a weight fraction of the block (A) therein being 50% by weight or more and 90% by weight or less. The phase difference film has an NZ factor of greater than 0 and smaller than 1. The method comprising: forming a single layer film of the resin C; and causing phase separation of the resin C in the film, which includes a step of applying to the film a stress along a thickness direction thereof.

The present disclosure relates to a polyester film and a preparation method of the same. Since the polyester film includes a resin layer formed from a polyester resin including a first diol moiety derived from isosorbide and a second diol moiety derived from cyclohexanedimethanol in a controlled ratio on at least one surface of a base layer, it is possible to exhibit excellent heat resistance and adhesion.

The present disclosure relates to a polyester film and a preparation method of the same. Since the polyester film includes a resin layer formed from a mixture comprising a polyester resin, which includes a first diol moiety derived from isosorbide and a second diol moiety derived from cyclohexanedimethanol in a controlled ratio, and polyethylene terephthalate in a specific ratio, it is possible to exhibit improved heat resistance and adhesion with excellent light transmittance.

The present disclosure relates to a polyester film and a preparation method of the same. Since the polyester film includes a resin layer formed from a mixture comprising a polyester resin, which includes a first diol moiety derived from isosorbide and a second diol moiety derived from cyclohexanedimethanol in a controlled ratio, and polyethylene terephthalate in a specific ratio, it is possible to exhibit improved heat resistance and adhesion with excellent light transmittance.

The present invention is to provide a method for producing a biaxially oriented polyester film that is superior in mechanical properties, transparency, and heat resistance, and at the same time, superior in secondary processing suitability and printing appearance. Disclosed is a biaxially oriented polyester film, having at least one surface satisfying the following requirements (1) and (2), and the film satisfying the following requirements (3) and (4). (1) A maximum peak height roughness (SRp) is 1.2 μm to 1.6 μm. (2) An arithmetic average roughness (SRa) is 0.024 μm to 0.045 μm. (3) A tensile strength in a longitudinal direction and a width direction is 180 MPa to 300 MPa. (4) A haze is 7% or less.

The present invention is to provide a method for producing a biaxially oriented polyester film that is superior in mechanical properties, transparency, and heat resistance, and at the same time, superior in secondary processing suitability and printing appearance. Disclosed is a biaxially oriented polyester film, having at least one surface satisfying the following requirements (1) and (2), and the film satisfying the following requirements (3) and (4). (1) A maximum peak height roughness (SRp) is 1.2 μm to 1.6 μm. (2) An arithmetic average roughness (SRa) is 0.024 μm to 0.045 μm. (3) A tensile strength in a longitudinal direction and a width direction is 180 MPa to 300 MPa. (4) A haze is 7% or less.

A polyolefin porous separator includes a first surface and a second surface corresponding to the first surface. The surfaces of the polyolefin porous separator contain dendritic crystals and micropores, the dendritic crystals intersect with the micropores on the first surface or/and the second surface, and the dendritic crystals penetrate through the second surface from the first surface. A preparation method of the polyolefin porous separator includes: (1) a mixed melting of polyethylene resin and a mineral oil; (2) an extrusion of the mineral oil/polyethylene resin molten mixture; (3) a stretching of a thick sheet in a machine direction (MD); (4) a stretching of the separator in a transverse direction (TD); (5) immersing the separator into a solvent to extract the mineral oil; (6) a secondary stretching of the separator in the TD; and (7) subjecting the separator having the longitudinal crystals to a heat-setting treatment and then rolling up.

A processing method for the dazzling colored base layer includes: outputting first materials and second materials alternately, a refractive index of the first materials being different from a refractive index of the second materials; obtaining a film by carrying out tape casting on the first materials and the second materials that are alternately arranged; and obtaining, by extending the film, the dazzling colored base layer having first material layers and second material layers that are alternately arranged, a thickness of the dazzling colored base layer being less than a thickness of the film.

To provide a gas barrier biaxially oriented polyamide film and a polyamide film mill roll, even as a product that is close to an end of a mill roll, having favorable mechanical characteristics, thermal characteristics, and few S-shape curling due to moisture absorption after being made into a bag. A biaxially oriented polyamide film having at least one layer formed of a polyamide resin containing not lower than 60% by mass of poly(m-xylylene adipamide), wherein a molecular orientation angle of the film is not smaller than 20°, a strain at moisture absorption of the film is not higher than 1.3%, an impact strength of the film is not lower than 0.7 J/15 μm, and a heat shrinkage rate, after heating for ten minutes at 160° C., of the film is 0.6 to 3.0% in both an MD direction and a TD direction.

To provide a gas barrier biaxially oriented polyamide film and a polyamide film mill roll, even as a product that is close to an end of a mill roll, having favorable mechanical characteristics, thermal characteristics, and few S-shape curling due to moisture absorption after being made into a bag. A biaxially oriented polyamide film having at least one layer formed of a polyamide resin containing not lower than 60% by mass of poly(m-xylylene adipamide), wherein a molecular orientation angle of the film is not smaller than 20°, a strain at moisture absorption of the film is not higher than 1.3%, an impact strength of the film is not lower than 0.7 J/15 μm, and a heat shrinkage rate, after heating for ten minutes at 160° C., of the film is 0.6 to 3.0% in both an MD direction and a TD direction.