Methods for preventing blisters in laminated glass articles and laminated glass articles formed therefrom

Abstract

A method for forming a laminated glass article may include flowing a molten first glass composition having a first R2O concentration and a first fining agent with a first fining agent concentration. The method may also include flowing a molten second glass composition having a second R2O concentration less than the first R2O concentration of the first glass composition and a second fining agent with a second fining agent concentration that is greater than or equal to the first fining agent concentration of the first glass composition. The molten first glass composition may be contacted with the molten second glass composition to form an interface between the molten first glass composition and the molten second glass composition.

What is claimed is: 
     
         1 . A laminated glass article comprising:
 a first glass layer formed from a first glass composition comprising a first R 2 O concentration and a first fining agent with a first fining agent concentration, wherein R is an element from Group I of the periodic table; and   a second glass layer fused to the first glass layer, the second glass layer formed from a second glass composition comprising a second R 2 O concentration less than the first R 2 O concentration of the first glass composition and a second fining agent with a second fining agent concentration that is greater than or equal to the first fining agent concentration of the first glass composition   wherein the first fining agent and the second fining agent are oxides of Sn, and a ratio of Sn +2  ions to a total concentration of Sn in the first molten glass composition is greater than or equal to about 0.15.   
     
     
         2 . The laminated glass article of  claim 1 , wherein a difference between the first R 2 O concentration and the second R 2 O concentration is at least 3 mol %. 
     
     
         3 . The laminated glass article of  claim 1 , wherein the laminated glass article comprises less than 1 blister defect/lb of the laminated glass article. 
     
     
         4 . The laminated glass article of  claim 1 , wherein the first glass composition comprising a first R 2 O, and wherein R comprises at least one of K, Na, and Li. 
     
     
         5 . The laminated glass article of  claim 1 , the second glass composition comprising a second R 2 O concentration that is less than the first R 2 O concentration of the first glass composition. 
     
     
         6 . The laminated glass article of  claim 1 , wherein a first glass composition corresponds to a core layer, the second glass composition corresponds to a cladding layer. 
     
     
         7 . The laminated glass article of  claim 1 , wherein a first glass composition corresponds to a cladding layer, the second glass composition corresponds to the core layer.