Durable anti-reflective articles

Patent metadata

Field	Value
Publication number	US-2025382473-A1
Application number	US-202519315994-A
Country	US
Kind code	A1
Filing date	Sep 2, 2025
Priority date	May 12, 2014
Publication date	Dec 18, 2025
Grant date	—

Abstract

Embodiments of durable, anti-reflective articles are described. In one or more embodiments, the article includes a substrate and an anti-reflective coating disposed on the major surface. The article exhibits an average light transmittance of about 94% or greater over an optical wavelength regime and/or an average light reflectance of about 2% or less over the optical wavelength regime, as measured from an anti-reflective surface. In some embodiments, the article exhibits a maximum hardness of about 8 GPa or greater as measured by a Berkovich Indenter Hardness Test along an indentation depth of about 50 nm or greater and a b* value, in reflectance, in the range from about −5 to about 1 as measured on the anti-reflective surface only at all incidence illumination angles in the range from about 0 degrees to about 60 degrees under an International Commission on Illumination illuminant.

First claim

What is claimed is:

1 . An article comprising:
a substrate having a major surface; and an anti-reflective coating having a thickness of about 0.2 μm to about 1 μm disposed on the major surface, the anti-reflective coating comprising an anti-reflective surface, wherein the anti-reflective coating comprises a plurality of layers, the plurality of layers comprising at least one low refractive index (RI) layer and at least one high RI layer, wherein the article exhibits a maximum hardness of about 8 GPa or greater as measured by a Berkovich Indenter Hardness Test along an indentation depth of about 50 nm or greater, wherein the article exhibits an average light reflectance of 2% or less over an optical wavelength regime in a range from about 400 nm to about 800 nm; wherein the article exhibits either one or both:
article transmittance color coordinates in the (L*, a*, b*) colorimetry system at normal incidence the D65 or F2 illuminant exhibiting a reference point color shift of less than about 2 from a reference point as measured at the anti-reflective surface, the reference point comprising at least one of the color coordinates (a*=0, b*=0) and the transmittance color coordinates of the substrate, and
article reflectance color coordinates in the (L*, a*, b*) colorimetry system at normal incidence exhibiting a color shift of less than about 5 from a reference point as measured at the anti-reflective surface, the reference point comprising at least one of the color coordinates (a*=0, b*=0), the coordinates (a*=−2, b*=−2), and the reflectance color coordinates of the substrate,
wherein, when the reference point is the color coordinates (a*=0, b*=0), the color shift is defined by √((a* article ) 2 +(b* article ) 2 ),
wherein, when the reference point is the color coordinates (a*=−2, b*=−2), the color shift is defined by √((a* article +2) 2 +(b* article +2) 2 ), and
wherein, when the reference point is the color coordinates of the substrate, the color shift is defined by √((a* article −a* substrate ) 2 +(b* article −b* substrate ) 2 ).

2 . The article of claim 1 , wherein the at least one low RI layer includes one low RI layer disposed on the major surface of the substrate, the one low RI layer has a physical thickness of greater than 10 nm to less than 150 nm.

3 . The article of claim 1 , wherein the substrate comprises an amorphous substrate, wherein the amorphous substrate comprises a glass selected from the group consisting of soda lime glass, alkali aluminosilicate glass, alkali containing borosilicate glass and alkali aluminoborosilicate glass, and wherein the glass is optionally chemically strengthened and comprises a compressive stress (CS) layer with a surface CS of at least 250 MPa extending within the chemically strengthened glass from a surface of the chemically strengthened glass to a depth of layer (DOL) of at least 10 μm.

4 . The article of claim 1 , wherein the article comprises one or more of following:
each high RI layer comprises Si 3 N 4 , SiN x , SiO x N y , or Si u Al y O x N y , a total physical thickness of the high RI layers is greater than 30% of the total physical thickness of the anti-reflective coating, and a total physical thickness of the high RI layers is ≥200 nm.

5 . The article of claim 1 , wherein the substrate is a crystalline substrate or a glass ceramic substrate.

6 . The article of claim 1 , wherein the article exhibits an abrasion resistance comprising any one of:
about 1% haze or less, as measured using a hazemeter having an aperture, wherein the aperture has a diameter of about 8 mm, an average roughness Ra, as measured by atomic force microscopy, of about 12 nm or less, a scattered light intensity of about 0.05 (in units of 1/steradian) or less, at a polar scattering angle of about 40 degrees or less, as measured at normal incidence in transmission using an imaging sphere for scatter measurements, with a 2 mm aperture at 600 nm wavelength, a scattered light intensity of about 0.1 (in units of 1/steradian) or less, at a polar scattering angle of about 20 degrees or less, as measured at normal incidence in transmission using an imaging sphere for scatter measurements, with a 2 mm aperture at 600 nm wavelength, wherein the abrasion resistance is measured after a 500-cycle abrasion using a Taber Test.

7 . The article of claim 1 , wherein the article exhibits a reflectance angular color shift of less than 5, as measured on the anti-reflective surface, at all angles from normal incidence to an incident illumination angle in the range from 0 degrees to 40 degrees under a F2 illuminant, and wherein angular color shift is calculated using the equation ((a* 2 −a* 1 ) 2 +(b* 2 −b* 1 ) 2 ), with a* 1 , and b* 1 representing the coordinates of the article when viewed at normal incidence and a* 2 , and b* 2 representing the coordinates of the article when viewed at the incident illumination angle.

8 . The article of claim 1 , wherein the anti-reflective coating has a physical thickness of from about 350 nm to about 1 μm.

9 . The article of claim 1 , wherein the anti-reflective coating has a physical thickness from about 0.2 m to about 325 nm.

10 . The article according of claim 1 , wherein the article is a cover article configured to: (a) protect devices within an electronic product, (b) provide a user interface for input to an electronic product, and/or (c) provide a display for an electronic product.

11 . An article comprising:
a substrate having a major surface; and an anti-reflective coating having a physical thickness of from about 0.2 m to about 1 μm disposed on the major surface, the anti-reflective coating comprising an anti-reflective surface, wherein the anti-reflective coating comprises a plurality of layers, the plurality of layers comprising at least one low refractive index (RI) layer and at least one high RI layer, wherein each low RI layer has a refractive index from about 1.3 to about 1.7 and each high RI layer has a refractive index of greater than about 1.7, wherein the article exhibits a maximum hardness of about 8 GPa or greater as measured by a Berkovich Indenter Hardness Test along an indentation depth of about 50 nm or greater, wherein the article exhibits an average light reflectance of 2% or less over an optical wavelength regime in a range from about 400 nm to about 800 nm, and wherein the article exhibits a reflectance angular color shift of less than 5, as measured on the anti-reflective surface, at all angles from normal incidence to an incident illumination angle in the range from 0 degrees to 40 degrees under a F2 illuminant, and wherein angular color shift is calculated using the equation ((a* 2 −a* 1 ) 2 +(b* 2 −b* 1 ) 2 ), with a* 1 , and b* 1 representing the coordinates of the article when viewed at normal incidence and a* 2 , and b* 2 representing the coordinates of the article when viewed at the incident illumination angle.

12 . The article of claim 11 , wherein the article exhibits a reflectance angular color shift of less than 5, as measured on the anti-reflective surface, at all angles from normal incidence to an incident illumination angle in the range from 0 degrees to 60 degrees under a F2 illuminant, and wherein angular color shift is calculated using the equation √((a* 2 −a* 1 ) 2 +(b* 2 −b* 1 ) 2 ), with a* 1 , and b* 1 representing the coordinates of the article when viewed at normal incidence and a* 2 , and b* 2 representing the coordinates of the article when viewed at the incident illumination angle.

13 . The article of claim 11 , wherein the article comprises one or more of following:
each high RI layer comprises Si 3 N 4 , SiN x

Assignees

• Corning Inc

Inventors

• Amin Jaymin
• Hart Shandon Dee
• Koch Iii Karl William
• Null Eric Louis
• Ouyang Xu
• Paulson Charles Andrew
• Price James Joseph

Classifications

• C03C21/002

  to perform ion-exchange between alkali ions (C03C21/005 takes precedence) · CPC title

• C03C17/3435 Primary

  comprising a nitride, oxynitride, boronitride or carbonitride · CPC title

• G02B1/115 Primary

  Multilayers · CPC title

• C03C17/3417 Primary

  all coatings being oxide coatings · CPC title

• C03C2217/734

  comprising an alternation of high and low refractive indexes · CPC title