Patent ID: 7069746

Claim:
A method for producing a fused glass article comprising the steps of: a) compacting pyrogenically produced metaloxide or metalloidoxide to form granules having a mean particle size less than about one mm; b) forming a green body from the granules or mixture of the granules according to step a) using a technique selected from uniaxial, cold isostatic or hot isostatic powder pressing, slip casting, extrusion, moulding or injection moulding; c) drying the green body in a first chamber by raising the temperature of the first chamber to above about 1000° C.; and d) fully sintering the green body in a second chamber by raising the temperature of the second chamber within a temperature range from about 1,200° C. to a temperature above about 1,720° C.; and e) hot isostatic pressing the fully sintered green body in a third chamber by raising the temperature of the third chamber to above about 1,500° C. and introducing an inert gas into the third chamber at a pressure above about 100 psig (6.895 bar).