Minimizing the formation of crystalline rhodium-platinum defects in glass manufactured within a precious metal system.

Abstract

A method for minimizing the formation of rhodium-platinum defects in a glass or glass-ceramic material or melt thereof is provided. The method includes providing a container made of a platinum-rhodium alloy for use in a manufacturing process to obtain the material, wherein an interface exists between the container and the melt. The method may include providing a sufficient partial pressure of hydrogen on the outside or inside of the container to control the partial pressure of oxygen in a region of the melt adjacent the interface. Also provided is a method for minimizing the formation of, or negating the effects of, localized thermal, electrical, or compositional cells in the melt during the manufacturing process. The method may include adding a polyvalent compound to the melt, adding a mixer to the finer tube, adding a mixing step to the manufacturing process, or amplifying the mixing.

Claims

1. In a method for minimizing the formation of rhodium-platinum defects in glass or glass-ceramic materials, A step of providing a container made of a platinum-rhodium alloy for use in a manufacturing process for obtaining the aforementioned material, wherein an interface exists between the container and the molten material. A step of providing the partial pressure of hydrogen outside the container to the partial pressure of hydrogen inside the container in an amount sufficient to control the partial pressure of oxygen in the region of the molten material adjacent to the interface, %O in the gas atmosphere outside the container ２ and a process of providing the partial pressure of hydrogen outside the container by controlling the dew point. Including, here, The rhodium-platinum defect is rhodium-rich, and the platinum-rhodium alloy in the container is platinum-rich. When the molten material is at a temperature in the range of 1000°C to 1300°C, the partial pressure of hydrogen outside the container is less than the partial pressure of hydrogen inside the container. The partial pressure of the oxygen increases in the region of the molten material adjacent to the interface. method.

2. The method according to claim 1, wherein the rhodium-platinum defect comprises a substantially planar geometric shape having a cross-sectional thickness of less than 3 μm and a diameter of 2 μm to 150 μm.

3. The method according to claim 2, wherein the rhodium-platinum defect comprises 80% rhodium and 20% platinum, and the platinum-rhodium alloy in the container comprises 80% platinum and 20% rhodium.

4. The method according to claim 3, wherein the material contains the rhodium-platinum defect if it does not provide a sufficient amount of hydrogen outside the container to control the partial pressure of oxygen in the region of the molten material adjacent to the interface, relative to the partial pressure of hydrogen inside the container.

5. When the molten material is at a temperature in the range of 1400°C to 1600°C, the partial pressure of hydrogen outside the container is greater than the partial pressure of hydrogen inside the container, and The partial pressure of the oxygen decreases within the region of the molten material adjacent to the interface. The method according to any one of claims 1 to 4.

6. The method according to any one of claims 1 to 4, comprising the step of adding water or a hydroxide-containing compound to the molten material to increase the partial pressure of hydrogen inside the container.

7. The method according to any one of claims 1 to 4, further comprising the step of bubbling a wet gas into the molten material to increase the partial pressure of hydrogen inside the container.

8. The method according to any one of claims 1 to 7, wherein the material comprises more than 0.1% by mass of a combination of tin oxide, iron oxide, manganese oxide, and cerium oxide, or at least 0.05% by mass of a combination of antimony oxide and arsenic oxide.

9. A method for minimizing the formation of rhodium-platinum defects in glass or glass-ceramic materials during a manufacturing process using a platinum-rhodium (PtRh) alloy in a manufacturing process vessel, wherein an interface exists between the vessel and the molten material, A step of providing the partial pressure of hydrogen outside the container to the partial pressure of hydrogen inside the container in an amount sufficient to control the partial pressure of oxygen in the region of the molten material adjacent to the interface, %O in the gas atmosphere outside the container ２ and a process of providing the partial pressure of hydrogen outside the container by controlling the dew point. Including, here, The rhodium-platinum defect is rhodium-rich, and the platinum-rhodium alloy in the container is platinum-rich. When the molten material is at a temperature in the range of 1000°C to 1300°C, the partial pressure of hydrogen outside the container is less than the partial pressure of hydrogen inside the container. The partial pressure of the oxygen increases in the region of the molten material adjacent to the interface. method.

10. The method according to claim 9, wherein the rhodium-platinum defect comprises a substantially planar geometric shape having a cross-sectional thickness of less than 3 μm and a diameter of 2 μm to 150 μm.

11. The method according to claim 10, wherein the rhodium-platinum defect comprises 80% rhodium and 20% platinum, and the platinum-rhodium alloy in the container comprises 80% platinum and 20% rhodium.

12. The method according to claim 11, wherein the material contains the rhodium-platinum defect if it does not provide a partial pressure of hydrogen outside the container to the partial pressure of hydrogen inside the container in an amount sufficient to control the partial pressure of oxygen in the region of the molten material adjacent to the interface.

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