Abstract: A white polyester film has a high level of whiteness, reflectivity, lightness, or thermal dimensional stability, and a surface light source that is produced with the white polyester film and has a high level of brightness characteristics. The white polyester film includes a white polyester layer (W layer) containing a polyester resin component (A) and a component (B) incompatible with the resin component (A) and having voids inside, wherein the incompatible component (B) is a cyclic-olefin resin (b) having a glass transition temperature of 110° C. or more, and the content Z of the cyclic-olefin resin (b) in the white polyester layer (W layer) is from 5% by weight to 50% by weight, based on the amount of the white polyester layer (W layer). The surface light source is produced therewith.

Abstract: A polyester film includes a polyester layer (W layer) containing an aromatic polyester resin (A) and a component (B) incompatible with the polyester resin (A), wherein the incompatible component (B) contains an acid-denaturated polyolefin resin (b2) and is dispersed as dispersion pieces with a flatness of 10 or higher in the polyester layer (W layer), and wherein volume occupancy of the dispersion pieces in the polyester layer (W layer) is 3 vol % to less than 50 vol %, and volume occupancy of voids in the polyester layer (W layer) is less than 3 vol %.

Abstract: A polyester film includes a polyester layer (W layer) containing an aromatic polyester resin (A) and a component (B) incompatible with the polyester resin (A), wherein the incompatible component (B) contains an acid-denaturated polyolefin resin (b2) and is dispersed as dispersion pieces with a flatness of 10 or higher in the polyester layer (W layer), and wherein volume occupancy of the dispersion pieces in the polyester layer (W layer) is 3 vol % to less than 50 vol %, and volume occupancy of voids in the polyester layer (W layer) is less than 3 vol %.

Abstract: [Object] In light of the problems in the prior art, an object of the invention is to provide a white laminated polyester film for a reflective plate sheet, which has a high reflectance and a high concealing property compatible with each other, and is not easily broken and is high in productivity. [Solving means] A white laminated polyester film for a reflecting sheet, including a polyester layer (B) containing voids therein, and a polyester layer (A) laminated at least on one surface side of the layer (B), the laminated polyester film satisfying the following (1) to (5): (1) the thickness of the polyester layer (A) laminated at least on one surface side is from 5 to 15 ?m; (2) the polyester layer (A) contains therein particles having a refractive index of 2.0 or more in an amount of 3 to 15% by weight of the polyester layer (A); (3) the thickness of the polyester layer (B) is 150 ?m or more; (4) the amount of particles having a refractive index of 2.

Abstract: A white film includes therein resin particles and voids formed around the resin particles, the film having a layer (S layer), wherein the number-average particle size Dn of the resin particles is 1.5 ?m or less, the resin particles are contained in a number of 0.05 or more particles/?m2, and a proportion of the number of resin particles having a particle diameter of 2 ?m or more is 15% or less.

Abstract: [Problems] To provide: a white polyester film excellent in whiteness, reflecting properties, lightweight properties, and dimensional stability to heat; and a surface light source employing the film and having excellent luminance characteristics. [Means for Solving Problems] The white polyester film comprises a white polyester layer (layer W) which comprises a polyester resin ingredient (A) and an ingredient (B) incompatible with the resin ingredient (A) and has bubbles therein. The incompatible ingredient (B) is a cycloolefin resin (b) having a glass transition temperature of 110° C. or higher, and the content (Z) of the cycloolefin resin (b) in the white polyester layer (layer W) is 5-50 wt. % based on the white polyester layer (layer W).

Abstract: An anisotropic diffusion film has a high brightness, high luminance uniformity ratio and a high productivity, and is suitable essentially for a surface light source of planar display devices for liquid crystal display devices and the like, such as a direct backlight. In the anisotropic diffusion film, a stripe-shaped convex lens is formed on one surface of a substrate film. The cross-sectional shape of a plane vertical to the stripe direction satisfies the following conditions that (A-C) and the whole of light transmittance of the anisotropic diffusion film is 70% or more: A: the contour of the projecting part of the cross-sectional shape is a curved line; B: the aspect ratio of the projecting part of the cross-sectional shape is 1 or more but not more than 3; and C: the distance between the apexes of the adjacent projecting parts of the cross-sectional shape is 10 ?m or more but not more than 100 ?m.