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.

1 - 14 . (canceled) 
     
     
         14 . An ultraviolet light-resistant article, comprising:
 a substrate comprising a glass or glass-ceramic and first and second primary surfaces;   a dielectric layer stack disposed on the first primary surface; and   at least one ultraviolet light-absorbing layer having an absorption greater than 50% at wavelengths from about 100 nm to about 380 nm and a thickness between about 10 nm and about 200 nm,   wherein the at least one light-absorbing layer is within the dielectric layer stack.   
     
     
         15 . The article according to  claim 14 , wherein the dielectric layer stack comprises a first dielectric layer and a second dielectric layer, wherein the first dielectric layer and the second dielectric layer comprise differing refractive index values from one another. 
     
     
         16 . The article according to  claim 15 , wherein the at least one ultraviolet light-absorbing layer is a single ultraviolet light-absorbing layer. 
     
     
         17 . The article according to  claim 14 , wherein the dielectric layer stack comprises an alternating sequence of dielectric layers and ultraviolet-light absorbing layers. 
     
     
         18 . The article according to  claim 14 , wherein the at least one ultraviolet light-absorbing layer has an extinction coefficient (k) of ≤5×10 −4  at wavelengths from about 380 nm to about 700 nm. 
     
     
         19 . The article according to  claim 14 , wherein the ultraviolet light-absorbing element has an extinction coefficient (k) of ≥5×10 −4  at wavelengths greater than about 700 nm. 
     
     
         20 . The article according to  claim 14 , wherein the substrate has a glass 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. 
     
     
         21 . The article according to  claim 14 , wherein the at least one ultraviolet light-absorbing layer comprises at least one of AlSiO x N y , Nb 2 O 5 , Ta 2 O 5 , TiO 2 , SnO 2  and ZnO. 
     
     
         22 . The article according to  claim 14 , wherein the total thickness of the dielectric layer stack is between about 10 nm and about 5000 nm. 
     
     
         23 . The article according to  claim 14 , wherein the article 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. 
     
     
         24 . The article according to claim  12 , wherein the at least one ultraviolet light-absorbing layer has a maximum indentation hardness, as measured by the Berkovich Indenter Hardness Test along an indentation depth of about 50 nm or greater, within about ±50% of the maximum indentation hardness of the article. 
     
     
         25 . The article according to  claim 14 , wherein the article exhibits an a* parameter color shift and a b* parameter color shift of less than about 4 after exposure to visible light at a normal incidence angle. 
     
     
         26 . The article according to  claim 14 , wherein the at least one ultraviolet light-absorbing layer has an absorption of greater than 75% at wavelengths from about 100 nm to about 380 nm. 
     
     
         27 . The article according to  claim 14 , wherein the at least one ultraviolet light-absorbing light has an absorption of greater than 90% at wavelengths from about 100 nm to about 380 nm. 
     
     
         28 . A method of making an ultraviolet light-resistant article, comprising:
 providing a substrate comprising a glass or glass-ceramic and first and second primary surfaces;   forming at least one ultraviolet light-absorbing layer over a first primary surface, the light-absorbing layer having an absorption of about 50% or greater at wavelengths from about 100 nm to about 380 nm and a thickness between about 10 nm and about 1000 nm; and   forming a dielectric layer with a plasma-assisted deposition process,   wherein the light-absorbing layer is configured to inhibit damage to the first primary surface of the substrate from the step of forming the dielectric layer.   
     
     
         29 . The method according to  claim 28 , wherein forming a dielectric layer comprises forming an alternating sequence of first and second dielectric layers over the first primary surface, the first and second dielectric layers characterized by differing refractive index values. 
     
     
         30 . The method according to  claim 29 , wherein forming at least one ultraviolet light-absorbing layer and a dielectric layer are conducted such that the at least one light-absorbing layer is a single ultraviolet light-absorbing layer formed on the first primary surface and the dielectric layer is formed over the light-absorbing layer. 
     
     
         31 . The method according to  claim 29 , wherein forming at least one ultraviolet light-absorbing layer and a dielectric layer are conducted such that the at least one light-absorbing layer is a single ultraviolet light-absorbing layer formed within the dielectric layer. 
     
     
         32 . The method according to  claim 28 , wherein forming a dielectric layer and at least one ultraviolet light-absorbing layer are performed at substantially the same time to form an alternating sequence of dielectric and ultraviolet light-absorbing layers. 
     
     
         33 . The method according to  claim 28 , wherein forming an ultraviolet light-absorbing layer and a dielectric layer are both conducted in a single deposition chamber. 
     
     
         34 . The method according to  claim 28 , wherein the substrate comprises a glass having 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. 
     
     
         35 . The method according to  claim 28 , wherein the ultraviolet light-absorbing layer comprises at least one of AlSiO x N y , Nb 2 O 5 , Ta 2 O 5 , TiO 2 , SnO 2  and ZnO. 
     
     
         36 . The method according to  claim 28 , wherein the substrate exhibits an a* parameter color shift and a b* parameter color shift of less than about 4 upon exposure to visible light at a normal incidence angle after the step of forming the ultraviolet light-absorbing layer. 
     
     
         37 . The method according to  claim 28 , wherein forming the ultraviolet light-absorbing layer and the dielectric layer are conducted such that the light-absorbing layer is formed within the dielectric layer. 
     
     
         38 . The method according to  claim 28 , further comprising:
 annealing the substrate at a temperature between about 200° C. and about 300° C. for about 1 to about 24 hours after forming the dielectric layer.   
     
     
         39 . (canceled) 
     
     
         40 . 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 14 .