CRT funnel glass capable of effectively recycling another glass member

Abstract

CRT funnel glass has a glass composition containing MgO, CaO, SrO, BaO and ZnO as essential components. Further, the total content of MgO, CaO, SrO, BaO and ZnO falls within a range of 5 to 13 mass %. As a glass material of the CRT funnel glass, CRT panel glass or CRT neck glass may be used.

What is claimed is:  
     
         1 . CRT funnel glass having a glass composition containing MgO, CaO, SrO, BaO and ZnO as essential components, the total content of MgO, CaO, SrO, BaO and ZnO falling within a range of 5 to 13 mass %.  
     
     
         2 . The CRT funnel glass according to  claim 1 , wherein a glass material of said CRT funnel glass is CRT panel glass.  
     
     
         3 . The CRT funnel glass according to  claim 1 , wherein a glass material of said CRT funnel glass is CRT neck glass.  
     
     
         4 . The CRT funnel glass according to  claim 1 , wherein the content of SrO and the content of BaO are each 1 mass % or greater.  
     
     
         5 . The CRT funnel glass according to  claim 1 , wherein an alkali elution amount of said CRT funnel glass is 0.4 mg or less.  
     
     
         6 . The CRT funnel glass according to  claim 1 , wherein a value of (MgO+CaO)/(SrO+BaO) is 0.47 or greater.  
     
     
         7 . The CRT funnel glass according to  claim 1 , wherein a thermal expansion coefficient of said glass at 30 to 380° C. falls within a range of 97×10 −7  to 104×10 −7 /° C., an annealing point of said glass falls within a range of 470 to 495° C., and a temperature corresponding to a viscosity of 10 4  dPa·s of said glass falls within a range of 940 to 990° C..  
     
     
         8 . The CRT funnel glass according to  claim 1 , wherein said CRT funnel glass has a glass composition containing, in mass %, 46 to 58% SiO 2 , 0.5 to 6% Al 2 O 3 , 10 to 30% PbO, 0.01 to 5% MgO, 0.01 to 6% CaO, 1 to 5% SrO, to 5% BaO, 0.01 to 5% ZnO, 5 to 13% MgO+CaO+SrO+BaO+ZnO, 3 to 9% Na 2 O, 4 to 11% K 2 O, and 0 to 2% Sb 2 O 3 .