Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
112 words
A sintered body of aluminum nitride produced by adding, as a sintering aid, an oxide mixture consisting essentially of calcium oxide, yttrium oxide and one or more oxides of tungsten oxide and molybdenum oxide or a mixture of compounds (precursors) capable of being converted into said oxide mixture by firing to aluminum nitride as a main component in such proportions that total amounts of said sintering aid is in the range 0.1 to 20% by weight (calculated as oxides of CaO, Y₂O₃, WO₃ and MoO₃) based on the sum of the weight as said oxides of the sintering aid and said aluminum nitride, molding the resulting composition and sintering the molded composition.
Claim 2
Dependent Claim
112 words
A sintered body of aluminum nitride produced by adding, as a sintering aid, an oxide mixture consisting essentially of calcium oxide, yttrium oxide and one or more oxides of tungsten oxide and molybdenum oxide or a mixture of compounds (precursors) capable of being converted into said oxide mixture by firing to aluminum nitride as a main component in such proportions that total amounts of said sintering aid is in the range 0.1 to 20% by weight (calculated as oxides of CaO, Y₂O₃, WO₃ and MoO₃) based on the sum of the weight as said oxides of the sintering aid and said aluminum nitride, molding the resulting composition and sintering the molded composition.
Claim 3
Dependent Claim
27 words
A sintered body of aluminum nitride as claimed in Claim 1 in which said mixture of said compounds contains one or more of CaWO₄, Ca₃WO₆ and CaMoO₄.
Claim 4
Dependent Claim
57 words
A sintered body of aluminum nitride as claimed in Claim 1 in which the total amount of said sintering aid is in the range of 0.2 to 15% by weight (calculated as said oxides of CaO, Y₂O₃, WO₃ and MoO₃) based on the sum of the weight as said oxides of said sintering aid and aluminum nitride.
Claim 5
Dependent Claim
37 words
A sintered body of aluminum nitride as claimed in Claim 1 in which the minimum amounts of said sintering aids are 0.03% for Y₂O₃, 0.02% for CaO and 0.05% for one or more of WO₃ and MoO₃.
Claim 6
Dependent Claim
37 words
A sintered body of aluminum nitride as claimed in Claim 3 in which the minimum amounts of said sintering aids are 0.5% for Y₂O₃, 0.05% for CaO and 0.3% for one or more of WO₃ and MoO₃.
Claim 7
Dependent Claim
30 words
A sintered body of aluminum nitride as claimed in Claim 4 in which the total amount of one or more of WO₃ and MoO₃ is at least 0.1% by weight.
Claim 8
Dependent Claim
30 words
A sintered body of aluminum nitride as claimed in Claim 4 in which the total amount of one or more of WO₃ and MoO₃ is at least 0.3% by weight.
Claim 9
Dependent Claim
24 words
A sintered body of aluminum nitride as claimed in Claim 4 in which Y₂O₃ is in the range of 0.5 to 7% by weight.
Claim 10
Dependent Claim
24 words
A sintered body of aluminum nitride as claimed in Claim 4 in which Y₂O₃ is in the range of 1 to 5% by weight.