Optical film, polarization plate, and image display device

Patent metadata

Field	Value
Publication number	US-10908333-B2
Application number	US-201816482116-A
Country	US
Kind code	B2
Filing date	Jan 30, 2018
Priority date	Jan 31, 2017
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

Provided is an optical film 10 including a light-transmitting base material 11 and a light-transmitting functional layer 12 provided on one surface of the light-transmitting base material 11 , wherein the optical film 10 has a spectral transmittance of less than 1% at a wavelength of 380 nm, a spectral transmittance of 10% or more and less than 60% at a wavelength of 410 nm, and a spectral transmittance of 70% or more at a wavelength of 440 nm, and wherein the light-transmitting functional layer 12 has a film thickness of 9 μm or less.

First claim

The invention claimed is:

1. An optical film comprising a light-transmitting base material and a light-transmitting functional layer provided on one surface of the light-transmitting base material, wherein the optical film has
a spectral transmittance of less than 1% at a wavelength of 380 nm,
a spectral transmittance of more than 10% and less than 60% at a wavelength of 410 nm, and
a spectral transmittance of 70% or more at a wavelength of 440 nm, and
wherein the light-transmitting functional layer has a film thickness of 9 μm or less.

2. The optical film according to claim 1 , wherein the optical film has a yellow index of 1 or more and 12 or less.

3. The optical film according to claim 1 , wherein the optical film has a blue light shielding rate of 30% or more.

4. The optical film according to claim 1 , wherein a slope of the transmittance spectrum obtained by applying a least square method to the transmittance in the wavelength range from 410 nm to 420 nm is 2 or more.

5. The optical film according to claim 1 , wherein the light-transmitting functional layer comprises a spectral transmittance adjustment layer that contains a resin and a spectral transmittance modifier.

6. A polarizing plate comprising
the optical film according to claim 1 , and
a polarizer provided on one surface of the optical film.

7. An image display device comprising
a display element, and
the optical film according to claim 1 placed on the observer's side of the display element.

8. The image display device according to claim 7 , wherein the display element is an organic light-emitting diode display element.

9. An image display device comprising
a display element, and
the polarizing plate according to claim 6 placed on the observer's side of the display element.

10. The optical film according to claim 1 , wherein the optical film has the spectral transmittance of 13% or more and less than 60% at a wavelength of 410 nm.

11. The optical film according to claim 1 , wherein the optical film has a spectral transmittance of 45% or more and 70% or less at a wavelength of 420 nm.

Assignees

• Dainippon Printing Co Ltd

Inventors

• Nomura Takahisa
• Hamada Takanori
• Nakashima Masataka
• Hata Kentaro
• Nakamura Hiroshi
• Nakagawa Hiroki

Classifications

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• G02B5/208 Primary

  for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation · CPC title

• G02B1/14 Primary

  Protective coatings, e.g. hard coatings · CPC title

• G09F9/335

  being organic light emitting diodes [OLED] · CPC title

• G02B5/3033

  in the form of a thin sheet or foil, e.g. Polaroid · CPC title