CN-121995553-A - Antireflection film

CN121995553ACN 121995553 ACN121995553 ACN 121995553ACN-121995553-A

Abstract

The present invention relates to an antireflection film. The antireflection film (1) is provided with a transparent base film (2), an intermediate layer (3), and an antireflection layer (4) in this order on one side in the thickness direction. The refractive index when light with a wavelength of 550nm is incident on the intermediate layer (3) is 1.7-1.9. The antireflection layer (4) comprises a laminate (10) comprising two or more layers (41) having a high refractive index and layers (42) having a low refractive index. When light with a wavelength of 550nm is incident on the high refractive index layer (41), the refractive index is greater than 2.50 and less than 2.80.

Inventors

WATANABE YASUNORI
Lin Xiongerlang
MIYAMOTO YUKIO

Assignees

日东电工株式会社

Dates

Publication Date: 20260508
Application Date: 20251107
Priority Date: 20241108

Claims (4)

1. An antireflection film comprising, in order from one side in the thickness direction, a transparent base film, an intermediate layer, and an antireflection layer, The refractive index of the intermediate layer when light with a wavelength of 550nm is incident thereon is 1.7 to 1.9, The antireflection layer includes a laminate of two or more layers having a high refractive index and a low refractive index, The refractive index when light with the wavelength of 550nm is made incident on the high refractive index layer is more than 2.50 and less than 2.80.
2. The antireflection film according to claim 1, wherein, The high refractive index layer contains crystals in which a diffraction spot group of Ti 2 O 3 appears in an electron beam diffraction image observed with a transmission electron microscope.
3. The antireflection film according to claim 1, wherein, The intermediate layer comprises an inorganic oxide.
4. The antireflection film according to any one of claims 1 to 3, wherein, When light having a wavelength of 380 to 780nm is incident on the antireflection film, the reflectance Y in the CIE-XYZ color system of the reflected light is 0.4% or less, The wavelength band with a spectral reflectance of 1% or less is 280nm or more.

Description

Antireflection film Technical Field The present invention relates to an antireflection film. Background In order to prevent reflection glare of external light, in image display devices such as liquid crystal displays and organic EL displays, an antireflection film is disposed on the outermost surface of a display screen. The antireflection film includes a transparent base film and an antireflection layer including a high refractive index layer and a low refractive index layer. As such an antireflection film, it has been proposed to achieve high antireflection performance in a wide wavelength band from the ultraviolet region to the infrared region by forming a film of an intermediate refractive index material between a transparent base film and an antireflection layer (for example, refer to patent document 1). Prior art literature Patent literature Patent document 1 Japanese patent laid-open publication No. 2003-248103 However, the average reflectance (reflectance Y) of the antireflection film in the wavelength range of 350 to 800nm is about 0.5%, and reflection glare of external light cannot be sufficiently prevented in image display devices such as liquid crystal displays and organic EL displays. On the other hand, in the antireflection film, the reflectance Y is desired to be further low in a wide wavelength band. Disclosure of Invention The invention provides an antireflection film with a wide wavelength band and low reflectivity. The invention [1] comprises an antireflection film comprising, in order on one side in the thickness direction, a transparent base film, an intermediate layer, and an antireflection layer, wherein the refractive index of the antireflection layer is 1.7 to 1.9 when light having a wavelength of 550nm is incident on the intermediate layer, and the antireflection layer comprises a laminate comprising two or more layers having a high refractive index and a low refractive index, and the refractive index of the antireflection layer when light having a wavelength of 550nm is incident on the high refractive index layer is greater than 2.50 and 2.80 or less. The invention [2] includes the antireflection film of [1], wherein the high refractive index layer contains crystals in which a diffraction spot group of Ti 2O3 appears in an electron beam diffraction image observed by a transmission electron microscope. The invention [3] includes the antireflection film of [1], wherein the intermediate layer contains an inorganic oxide. The invention [4] includes the antireflection film according to any one of [1] to [3], wherein a reflectance Y in a CIE-XYZ color system of reflected light when light having a wavelength of 380 to 780nm is made incident on the antireflection film is 0.4% or less, and a wavelength band having a spectral reflectance of 1% or less is 280nm or more. Effects of the invention The antireflection film of the present invention comprises, in order on one side in the thickness direction, a transparent base film, an intermediate layer, and an antireflection layer, wherein the refractive index of the antireflection layer is 1.7 to 1.9 inclusive when light having a wavelength of 550nm is incident on the intermediate layer, and the antireflection layer comprises a laminate of two or more high refractive index layers and low refractive index layers, and the refractive index of the antireflection layer when light having a wavelength of 550nm is incident on the high refractive index layers is greater than 2.50 and 2.80 inclusive. Therefore, the reflectance Y of the antireflection film can be reduced in a wide wavelength band. Drawings Fig. 1 is a cross-sectional view of an embodiment of the antireflection film of the present invention. Fig. 2A to 2E illustrate a method for manufacturing the antireflection film shown in fig. 1. Fig. 2A shows a step of preparing a transparent resin film, fig. 2B shows a step of forming a cured resin layer on the transparent resin film, fig. 2C shows a step of forming an intermediate layer on the cured resin layer, fig. 2D shows a step of forming an antireflection layer on the intermediate layer, and fig. 2E shows a step of forming an antifouling layer on the antireflection layer. Fig. 3 is a cross-sectional view showing an embodiment of a modified example of the antireflection film shown in fig. 1. Description of the reference numerals 1, Antireflection film, 2, transparent base film, 3, intermediate layer, 4, antireflection layer, 5, antifouling layer, 10, laminate, 10a, first laminate, 10b, second laminate, 21, transparent resin film, 22, cured resin layer, 41, high refractive index layer, 41a, first high refractive index layer, 41b, second high refractive index layer, 42, low refractive index layer, 42a, first low refractive index layer, 42b, second low refractive index layer. Detailed Description 1. Antireflection film An embodiment of the antireflection film of the present invention will be described with reference to fig. 1. As shown in fig. 1, th