Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
118 words
A transparent, translucent, or opaque glass-ceramic article exhibiting colors ranging from black to brown to red and containing β-quartz solid solution as the predominant crystal phase, said glass-ceramic article being essentially free from MgO and consisting essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________
SiO.sub.2
63.5-69 BaO 0-5
Al.sub.2 O.sub.3
15-25 TiO.sub.2
>2.5-6
Li.sub.2 O
2.5-4 ZrO.sub.2
0-2
Na.sub.2 O
0.1-0.6 As.sub.2 O.sub.3
0.4-0.8
K.sub.2 O
0.1-0.6 Fe.sub.2 O.sub.3
0.05-0.2
ZnO 0-2
______________________________________ and 0.3-3% total of at least two oxides in the indicated proportions selected from the group of 0-2% CaO, 0-3% CeO 2 , 0-1% NiO, 0-1.5% SnO 2 , 0-0.3% V 2 O 5 , and 0-1% WO 3 .
Claim 2
Dependent Claim
118 words
A transparent, translucent, or opaque glass-ceramic article exhibiting colors ranging from black to brown to red and containing β-quartz solid solution as the predominant crystal phase, said glass-ceramic article being essentially free from MgO and consisting essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________
SiO.sub.2
63.5-69 BaO 0-5
Al.sub.2 O.sub.3
15-25 TiO.sub.2
>2.5-6
Li.sub.2 O
2.5-4 ZrO.sub.2
0-2
Na.sub.2 O
0.1-0.6 As.sub.2 O.sub.3
0.4-0.8
K.sub.2 O
0.1-0.6 Fe.sub.2 O.sub.3
0.05-0.2
ZnO 0-2
______________________________________ and 0.3-3% total of at least two oxides in the indicated proportions selected from the group of 0-2% CaO, 0-3% CeO 2 , 0-1% NiO, 0-1.5% SnO 2 , 0-0.3% V 2 O 5 , and 0-1% WO 3 .
Claim 3
Dependent Claim
61 words
A glass-ceramic article according to claim 1 also containing up to 3% total of at least one oxide selected from the group of B 2 O 3 , Cr 2 O 3 , Cs 2 O, Cu 2 O, La 2 O 3 , MnO, and Nb 2 O 5 , wherein the individual value of each oxide is below 1%.
Claim 4
Dependent Claim
119 words
An opaque glass-ceramic article exhibiting colors ranging from gray to brown to almond to beige to yellow to blue and containing β-spodumene as the predominant crystal phase, said glass-ceramic article being essentially free from MgO and consisting essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________
SiO.sub.2
63.5-69 BaO 0-5
Al.sub.2 O.sub.3
15-25 TiO.sub.2
>2.5-6
Li.sub.2 O
2.5-4 ZrO.sub.2
0-2
Na.sub.2 O
0.1-0.6 As.sub.2 O.sub.3
0.4-0.8
K.sub.2 O
0.1-0.6 Fe.sub.2 O.sub.3
0.05-0.2
ZnO 0-2
______________________________________ and 0.3-3% total of at least two oxides in the indicated proportions selected from the group of 0-2% CaO, 0-3% CeO 2 , 0-1% NiO, 0-1.5% SnO 2 , 0-0.3% V 2 O 5 , and 0-1% WO 3 .
Claim 5
Dependent Claim
119 words
An opaque glass-ceramic article exhibiting colors ranging from gray to brown to almond to beige to yellow to blue and containing β-spodumene as the predominant crystal phase, said glass-ceramic article being essentially free from MgO and consisting essentially, expressed in terms of weight percent on the oxide basis, of: ______________________________________
SiO.sub.2
63.5-69 BaO 0-5
Al.sub.2 O.sub.3
15-25 TiO.sub.2
>2.5-6
Li.sub.2 O
2.5-4 ZrO.sub.2
0-2
Na.sub.2 O
0.1-0.6 As.sub.2 O.sub.3
0.4-0.8
K.sub.2 O
0.1-0.6 Fe.sub.2 O.sub.3
0.05-0.2
ZnO 0-2
______________________________________ and 0.3-3% total of at least two oxides in the indicated proportions selected from the group of 0-2% CaO, 0-3% CeO 2 , 0-1% NiO, 0-1.5% SnO 2 , 0-0.3% V 2 O 5 , and 0-1% WO 3 .
Claim 6
Dependent Claim
61 words
A glass-ceramic article according to claim 3 also containing up to 3% total of at least one oxide selected from the group of B 2 O 3 , Cr 2 O 3 , Cs 2 O, Cu 2 O, La 2 O 3 , MnO, and Nb 2 O 5 , wherein the individual value of each oxide is below 1%.