To provide a functional film (hard coat film) free from occurrence of interference spots under a three wavelength fluorescent lamp even if the refractive index of a primer layer is substantially different from that of a plastic film support in a constitution of the transparent plastic film support, the primer layer, and a functional layer (hard coat layer).
In the plastic film, the primer layer (B) having the film thickness of ≤1 μm and the functional layer (C) having the film thickness of ≥1 μm are laminated in this order at least at one surface at least of the transparent plastic film support (A), wherein the transparent plastic film support (A) and the functional layer (a hard coat layer, for example) (C) have no substantial difference in refractive index at a wavelength of 546 nm and also, the transparent plastic film support (A) and the primer layer (B) are substantially different in refractive index at a wavelength of 546 nm, and the film thickness dp of the primer layer (B) satisfies the formula, dp=(N×546±50)/(2np) nm, wherein np is the refractive index of the primer layer (B), N is a natural number.
Hironori Honda
Toshimitsu Ichikawa
Takeshi Takamatsu
Yuriko Hamada
Next Patent: RESIN PLATE END FACE TREATING DEVICE