A vacuum insulated structure for use in an appliance includes an inner liner and an outer wrapper coupled to the inner liner. A vacuum insulated cavity is defined therebetween. An insulation material is disposed in the vacuum insulated cavity. The insulation material includes porous glass flakes.

A vacuum insulated structure for use in an appliance includes an inner liner and an outer wrapper coupled to the inner liner. A vacuum insulated cavity is defined therebetween. An insulation material is disposed in the vacuum insulated cavity. The insulation material includes porous glass flakes.

A method of forming an insulation material for a vacuum insulated structure includes heating glass flakes to at least a glass transition temperature of the glass flakes to induce a phase separation of the glass into an acid insoluble silica phase and an acid soluble phase. The glass flakes can be derived from a glass composition containing (by weight): SiO.sub.2 from about 40% to about 80%, B.sub.2O.sub.3 from about 10% to about 40%, Na.sub.2O from about 1% to about 10%, Li.sub.2O from about 0% to about 3%, CaO from about 0% to about 10%, ZnO from about 0% to about 5%, P.sub.2O.sub.5 from about 0% to about 10%, and Al.sub.2O.sub.3 from about 0% to about 10%. The method also includes a step of etching the glass flakes to dissolve the acid soluble phase to form porous glass flakes.

A resin composition for inorganic molded article production use, which is provided with inorganic particles each containing amorphous SiO.sub.2 and a photocurable resin composition, in which the photocurable resin composition contains a photocurable resin precursor and a photopolymerization initiator, the content of the inorganic particles is 60% by mass or more with respect to the total amount of the photocurable resin composition and the inorganic particles and is 60% by mass or more with respect to the entire amount of the resin composition for inorganic molded article production use, and the viscosity of the composition for inorganic molded article production use is 10000 mPa.Math.s or less.

A processing technique for production of fused silica for radomes and like elements is described. The processing technique includes forming a mixture of milled silica having an average particle size of about 1 to 5 microns, and a colloidal silica. This mixture is processed to form fused silica having substantially high strength.

A resin composition for inorganic molded article production use, which is provided with inorganic particles each containing amorphous SiO.sub.2 and a photocurable resin composition, in which the photocurable resin composition contains a photocurable resin precursor and a photopolymerization initiator, the content of the inorganic particles is 60% by mass or more with respect to the total amount of the photocurable resin composition and the inorganic particles and is 60% by mass or more with respect to the entire amount of the resin composition for inorganic molded article production use, and the viscosity of the composition for inorganic molded article production use is 10000 mPa.Math.s or less.

The invention relates to a continuous sol-gel method for producing quartz glass, comprising the following steps: (a) continuously metering a silicon alkoxide into a first reactor (R1) and carrying out an at least partial hydrolysis process by adding an aqueous mineral acid, thereby obtaining a first product flow (A); (b) continuously producing an aqueous silicic acid dispersion by continuously mixing water and silicic acid in a second reactor, thereby obtaining a second product flow (B); (c) continuously mixing the product flows (A) and (B) in a third reactor (R3) in order to produce a pre-sol, thereby obtaining a third product flow (C); (d) continuously adding an aqueous base to the product flow (C), thereby obtaining a sol; (e) continuously filling the exiting sol into moulds, thereby obtaining an aquagel; (f) drying the aquagel, thereby obtaining xerogels; and (g) sintering the xerogels, thereby obtaining quartz glass, with the proviso that at least one of the steps (a) to (e) additionally includes a degassing process of at least one feed material used in the step.