Ultraviolet light-resistant articles and methods for making the same

Abstract

An ultraviolet light-resistant article that includes: a substrate having a glass or glass-ceramic composition and first and second primary surfaces; an ultraviolet light-absorbing element having a an absorptivity greater than 50% at wavelengths from about 100 nm to about 380 nm and a thickness between about 10 nm and about 100 nm; and a dielectric stack formed with a plasma-enhanced process. Further, the light-absorbing element is between the substrate and the dielectric stack. Alternatively, the light-absorbing element can include one or more ultraviolet light-resistant layers disposed within the dielectric stack over the first primary surface.

We claim: 
     
         1 . An article, comprising:
 an assembly, comprising:
 at least one dielectric layer; 
 at least one first ultraviolet light-absorbing layer comprising a nitride; and 
 at least one second ultraviolet light-absorbing layer comprising at least one of Nb 2 O 5  or TiO 2 ; 
   wherein the assembly has a maximum hardness of 8 GPa or greater, as measured by the Berkovich Indenter Hardness Test.   
     
     
         2 . The article of  claim 1 , wherein total thickness of the at least one first ultraviolet light-absorbing layer comprising a nitride is larger than total thickness of the at least one second ultraviolet light-absorbing layer comprising at least one of Nb 2 O 5  or TiO 2 . 
     
     
         3 . The article of  claim 1 , wherein the nitride is an aluminum oxynitride. 
     
     
         4 . The article of  claim 1 , wherein the nitride is an aluminum silicon oxynitride. 
     
     
         5 . The article of  claim 1 , wherein the at least one second ultraviolet light-absorbing layer comprises Nb 2 O 5 . 
     
     
         6 . The article of  claim 1 , wherein the at least one second ultraviolet light-absorbing layer comprises TiO 2 . 
     
     
         7 . The article of  claim 1 , wherein the at least one second ultraviolet light-absorbing layer comprises an ultraviolet light-absorbing layer comprising Nb 2 O 5  and an ultraviolet light-absorbing layer comprising TiO 2 . 
     
     
         8 . The article of  claim 1 , wherein the at least one dielectric layer comprises SiO 2 . 
     
     
         9 . The article of  claim 1 , wherein the at least one dielectric layer comprises first and second dielectric layers characterized by differing refractive index values. 
     
     
         10 . The article of  claim 1 , comprising an alternating sequence of the at least one dielectric layer with at least one of the first and second ultraviolet light-absorbing layers located therebetween. 
     
     
         11 . The article of  claim 1 , wherein the at least one dielectric layer comprises three or more dielectric layers. 
     
     
         12 . The article of  claim 1 , wherein the assembly has a maximum indentation hardness of 8 GPa or greater, as measured by the Berkovich Indenter Hardness Test along an indentation depth of about 50 nm or greater. 
     
     
         13 . The article of  claim 1 , wherein the at least one first ultraviolet light-absorbing layer or the at least one second ultraviolet light-absorbing layer has a maximum indentation hardness, as measured by the Berkovich Indenter Hardness Test, within about ±50% of the maximum indentation hardness of the assembly. 
     
     
         14 . The article of  claim 1 , wherein a total thickness of the at least one dielectric layer, the at least one first ultraviolet light-absorbing layer, and the at least one second ultraviolet light-absorbing layer is between about 10 nm and about 2000 nm. 
     
     
         15 . The article of  claim 1 , wherein the first and second ultraviolet light-absorbing layers each have a thickness between 10 nm and 500 nm. 
     
     
         16 . The article of  claim 1 , further comprising at least one third ultraviolet light-absorbing layer comprising at least one of Ta 2 O 5 , SnO 2  or ZnO, 
     
     
         17 . The article of  claim 1 , wherein at least one of the first and second ultraviolet light-absorbing layers has at least one of:
 an extinction coefficient (k) of ≤5×10-4 at wavelengths from about 400 nm to about 700 nm;   an absorption of greater than 75% at wavelengths from about 100 nm to about 380 nm.   
     
     
         18 . The article of  claim 1 , further comprising a substrate comprising a glass or glass-ceramic having first and second primary surfaces, wherein the assembly is disposed on the first primary surface. 
     
     
         19 . The article of  claim 18 , wherein the substrate has a composition comprising SiO 2 , Al 2 O 3  and at least two oxides selected from the group consisting of B 2 O 3 , P 2 O 5 , MgO, CaO, SrO, BaO, ZnO, Na 2 O, K 2 O, and Li 2 O. 
     
     
         20 . A device comprising:
 a housing having a front surface, a back surface and side surfaces;   electrical components provided at least partially inside the housing;   a display at or adjacent the front surface of the housing; and   a cover substrate disposed over the display, wherein the cover substrate comprises the article of  claim 1 .