US 12,117,632 B2
Laminate film
Hisato Matsui, Otsu (JP); Yuji Matsuo, Otsu (JP); and Wataru Gouda, Otsu (JP)
Assigned to Toray Industries, Inc., Tokyo (JP)
Appl. No. 17/273,486
Filed by Toray Industries, Inc., Tokyo (JP)
PCT Filed Sep. 4, 2019, PCT No. PCT/JP2019/034733
§ 371(c)(1), (2) Date Mar. 4, 2021,
PCT Pub. No. WO2020/054529, PCT Pub. Date Mar. 19, 2020.
Claims priority of application No. 2018-170397 (JP), filed on Sep. 12, 2018.
Prior Publication US 2021/0341659 A1, Nov. 4, 2021
Int. Cl. G02B 5/26 (2006.01); B32B 7/023 (2019.01); B32B 27/08 (2006.01); B32B 27/36 (2006.01)
CPC G02B 5/26 (2013.01) [B32B 7/023 (2019.01); B32B 27/08 (2013.01); B32B 27/36 (2013.01); B32B 2250/05 (2013.01); B32B 2250/244 (2013.01); B32B 2270/00 (2013.01); B32B 2307/418 (2013.01); B32B 2307/516 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A laminate film comprising 51 or more layers including layers A each containing a thermoplastic resin A as primary component and layers B each containing a thermoplastic resin B, which is different from the thermoplastic resin A, as primary component that are stacked alternately, and
meeting the relation of 150≤Amax≤1,500 wherein Amax (nm·%) represents the area of the largest of the regions surrounded by a transmission spectrum X and a transmission spectrum Y, the transmission spectrum X being a transmission spectrum obtained on a graph with wavelength (nm) on the horizontal axis and transmittance (%) on the vertical axis showing plotted results of observation in which a linearly polarized light (X wave) vibrating in the orientation direction of the film is used for irradiation over the wavelength range of 300 nm or more and 900 nm or less and the transmission spectrum Y being a transmission spectrum obtained on the graph with wavelength (nm) on the horizontal axis and transmittance (%) on the vertical axis showing plotted results of observation in which a linearly polarized light (Y wave) vibrating in the direction perpendicular to the orientation direction of the film is used for irradiation over the wavelength range of 300 nm or more and 900 nm or less, and
Amax (nm %) is calculated by Equation (3) where T′n and Tn are the X wave transmittance and the Y wave transmittance, respectively, at a shorter wavelength (wavelength of n [nm]) and T′n+1 and Tn+1 are the X wave transmittance and the Y wave transmittance, respectively, at a longer wavelength (wavelength of n+1 [nm]), and a and b denote the wavelengths at the intersections of the transmission spectra and meet the relation of 300≤a<b≤900, and
an orientation angle, measured from the width direction of the film which is defined as 0° is 15° or less at all three points of the width-directional center of the film and the midpoints between the width-directional center and the width-directional ends according to Mathematical Formula 3:
Amax=∫ab{(Tn−T′n)+(Tn+1−T′n+1)}/2dn  (3)
(where a and b denote the wavelengths at the intersections of the transmission spectra and meet the relation of 300≤a<b≤900).