Patent EP0260893A2 successfully refreshed from Google Patents.
EP0260893A2
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EP
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Heat resisting low expansion zirconyl phosphate-zircon composite bodies and process for producing the same
Assignee: NGK Insulators Ltd
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Filing: 1987-09-11
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Granted: —
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Expires: 2007-09-11
Abstract
Abstract Heat resisting low expansion zirconyl phosphate-zircon composite bodies are disclosed, which contain zirconyl phosphate and zircon as a main crystalline phase and a secondary crystalline phase, respectively. The heat resisting low expansion zirconyl phosphate-zircon composite bodies have a coefficient of thermal expansion in a temperature range from room temperature to 1,400°C being not more than 30×10⁻⁷/°C and a melting point being not less than 1,600°C. The composite bodies have a chemical composition essentially consisting of 58.2 to 65.4% by weight of ZrO₂, 17.4 to 37.1% by weight of P₂O₅, and 1.5 to 19.0% by weight of SiO₂. The heat resisting low expansion zirconyl phosphate-zircon composite bodies optionally contain MgO and Aℓ₂O₃ in a total amount of not more than 2.5% by weight or 0.1 to 4% by weight of Nb₂O₅. A process for producing such zirconyl phosphate-zircon composite bodies is also disclosed.
Inventors
- 👤 Keiichiro 4E Co.Nakanomachi House Watanabe
- 👤 Tsuneaki Ngk Takemi-Ryo Ohashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 15:38
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/48; C04B35/481; C04B35/447
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
55 words
A heat resisting low expansion zirconyl phosphate-zircon composite body which contains zirconyl phosphate and zircon as a main crystalline phase and a secondary crystalline phase, respectively, wherein a coefficient of thermal expansion in a temperature range from room temperature to 1,400°C is not more than 30×10⁻⁷/°C and a melting point is not less than 1,600°C.
Claim 2
Dependent Claim
55 words
A heat resisting low expansion zirconyl phosphate-zircon composite body which contains zirconyl phosphate and zircon as a main crystalline phase and a secondary crystalline phase, respectively, wherein a coefficient of thermal expansion in a temperature range from room temperature to 1,400°C is not more than 30×10⁻⁷/°C and a melting point is not less than 1,600°C.
Claim 3
Dependent Claim
41 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which contains 58.2 to 65.4% by weight of ZrO₂, 17.4 to 37.1% by weight of P₂O₅ and 1.5 to 19.0% by weight of SiO₂ in the chemical composition.
Claim 4
Dependent Claim
78 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which contains 58.2 to 64.8% by weight of ZrO₂, 22.5 to 37.1% by weight of P₂O₅ and 1.5 to 14.1% by weight of SiO₂ in the chemical composition and contains zirconyl phosphate and zircon as the main crystalline phase and the secondary crystalline phase, respectively, wherein the coefficient of thermal expansion in the temperature range from room temperature to 1,400°C is not more than 20×10⁻⁷°C.
Claim 5
Dependent Claim
43 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which has a chemical composition essentially consisting of 61.3 to 65.4% by weight of ZrO₂, 18.3 to 37.1% by weight of P₂O₅, and 1.6 to 16.4% by weight of SiO₂.
Claim 6
Dependent Claim
78 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which contains 61.3 to 64.8% by weight of ZrO₂, 23.7 to 37.1% by weight of P₂O₅ and 1.6 to 11.5% by weight of SiO₂ in the chemical composition and contains zirconyl phosphate and zircon as the main crystalline phase and the secondary crystalline phase, respectively, wherein the coefficient of thermal expansion in the temperature range from room temperature to 1,400°C is not more than 20×10⁻⁷/°C.
Claim 7
Dependent Claim
35 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, wherein a total amount of oxides of an alkali metal and an alkaline earth metal is not more than 0.5% by weight.
Claim 8
Dependent Claim
54 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which comprises 58.2 to 65.3% by weight of ZrO₂, 17.4 to 37.1% by weight of P₂O₅, 1.6 to 19.0% by weight of SiO₂, and the balance being MgO and Aℓ₂O₃ in a total amount of not more than 2.5% by weight.
Claim 9
Dependent Claim
74 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 7, which contains 58.2 to 64.7% by weight of ZrO₂, 22.5 to 37.1% by weight of P₂O₅, 1.6 to 14.1% by weight of SiO₂, and the balance being MgO and Aℓ₂O₃ in a total amount of not more than 2.5% by weight, wherein the coefficient of thermal expansion in the temperature range from room temperature to 1,400°C is not more than 20×10⁻⁷/°C.
Claim 10
Dependent Claim
37 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 7, wherein a total amount of oxides of an alkali metal and an alkaline earth metal excluding MgO is not more than 0.5% by weight.
Claim 11
Dependent Claim
50 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 1, which has a chemical composition essentially consisting of 58.8 to 65.3% by weight of ZrO₂, 17.6 to 37.1% by weight of P₂O₅, 1.5 to 16.4% by weight of SiO₂, and 0.1 to 7% by weight of Nb₂O₅.
Claim 12
Dependent Claim
70 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 10, which has the chemical composition essentially consisting of 58.8 to 64.7% by weight of ZrO₂, 22.7 to 37.1% by weight of P₂O₅, 1.5 to 11.5% by weight of SiO₂, and 0.1 to 4% by weight of Nb₂O₅, wherein the coefficient of thermal expansion at the temperature range from room temperature to 1,400°C is not more than 20×10⁻⁷/°C.
Claim 13
Dependent Claim
35 words
A heat resisting low expansion zirconyl phosphate-zircon composite body according to claim 10, wherein the total amount of oxides of an alkali metal and an alkaline earth metal is not more than 0.5% by weight.
Claim 14
Dependent Claim
79 words
A process for producing zirconyl phosphate-zircon composite body containing zirconyl phosphate and zircon as a main crystalline phase and a secondary crystalline phase, respectively, wherein a coefficient of thermal expansion in a temperature range from room temperature to 1,400°C is not more than 30×10⁻⁷/°C and a melting point is not less than 1,600°C, said process comprising adding 5 to 50% by weight of zircon (ZrSiO₄) to zirconyl phosphate [(ZrO)₂P₂O₇] to obtain a batch mixture and sintering the batch mixture.
Claim 15
Dependent Claim
79 words
A process for producing zirconyl phosphate-zircon composite body containing zirconyl phosphate and zircon as a main crystalline phase and a secondary crystalline phase, respectively, wherein a coefficient of thermal expansion in a temperature range from room temperature to 1,400°C is not more than 30×10⁻⁷/°C and a melting point is not less than 1,600°C, said process comprising adding 5 to 50% by weight of zircon (ZrSiO₄) to zirconyl phosphate [(ZrO)₂P₂O₇] to obtain a batch mixture and sintering the batch mixture.
Claim 16
Dependent Claim
46 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 13, wherein an addition amount of zircon is from 5 to 35% by weight and the coefficient of thermal expansion in the temperature range from room temperature to 1,400°C is not more than 20×10⁻⁷/°C.
Claim 17
Dependent Claim
40 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 13, wherein zirconyl phosphate and zircon which totally contain not more than 0.5% by weight of oxides of an alkali metal and an alkaline earth metal are used.
Claim 18
Dependent Claim
42 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 13, wherein 0.1 to 5 parts by weight of cordierite (2MgO·2Aℓ₂O₃.5SiO₂) is added to 100 parts by weight of the batch mixture, and a thus obtained mixture is then sintered.
Claim 19
Dependent Claim
44 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 16, wherein an Nb₂O₅ starting material containing not more than 0.5% by weight of the oxides of the alkali metal and the alkaline earth metal oxides in the total amount is used.
Claim 20
Dependent Claim
41 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 16, wherein 0.1 to 4 parts by weight of Nb₂O₅ is added to 100 parts by weight of the batch mixture, and then a thus obtained mixture is sintered.
Claim 21
Dependent Claim
41 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 18, wherein a cordierite starting material containing not more than 1% by weight of the oxides of the alkali metal and the alkaline earth metal excluding MgO is used.
Claim 22
Dependent Claim
29 words
A process for producing a zirconyl phosphate-zircon composite body according to claim 13, wherein a molar ratio of ZrO₂/P₂O₅ in a zirconyl phosphate starting material is 1.8 to 2.00.
References Cited (Backward Citations)
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