Abstract: Disclosed are apparatus and method for ultrasonically dispersing a silica sol such as is used in a process of manufacturing a silica glass by a sol-gel method. The apparatus includes a sol feeder for holding a sol to be dispersed, a sol container for containing the ultrasonically dispersed sol, a medium tank having a liquid-phase ultrasonic medium, an ultrasonic vibrator for generating ultrasonic waves within the tank, and a sol pipe for providing a sol feeding path connecting the sol feeder and the sol container to each other, the sol pipe having a portion submerged under the ultrasonic medium in the medium tank. The portion of the sol pipe submerged under the ultrasonic medium has a shape bent in a zigzagged fashion.

Abstract: A composition for production of silica glass using a sol-gel process is described, comprising silica particles, a dispersing agent, and a solution containing a polymerizable monomer for formation of acrylic resin and a crosslink agent dissolved in distilled water. The polymerizable monomer is n-methylol acrylamide or n-methylol methacrylamide. A method for production of silica glass is described, including the step of adding silica particles and a dispersing agent to a premix solution of the polymerizable monomer for formation of acrylic resin and the crosslink agent dissolved in distilled water.

Abstract: Disclosed is a method for fabricating high-purity silica glass using a sol-gel processing that includes the steps of: (a) mixing a deionized water with a fluorine compound and a dispersion agent to prepare an aqueous premix solution; (b) mixing the aqueous premix solution with a fumed silica; (c) mixing the resulting mixture to form a dispersed sol; (d) aging the sol at the ambient temperature to stabilize silica particles; and, (e) removing air voids from the sol and adding a gelation agent.

Abstract: Disclosed is a method for fabricating high-purity silica glass using a sol-gel processing that includes the steps of: (a) mixing deionized water with a monomer and a dimer to prepare an aqueous premix solution; (b) mixing the aqueous premix solution with a fused silica and a dispersion agent; (c) mixing the resulting mixture to form a dispersed sol; (d) aging the dispersed sol at the ambient temperature to stabilize silica particles, and removing air voids from the sol; and, (e) adding a polymerization initiator and a gelation agent to the aged sol.

Abstract: A method for fabricating a silica glass is provided. The method includes the steps of adding silica and a dispersant to a premix solution obtained by dissolving an acrylic resin monomer and a cross-linking agent in distilled water, dispersing the mixed solution and adjusting the pH of the mixture, to form a sol. Air bubbles are removed from the sol, and then the resultant sol is aged. A polymerization initiator and a catalyst are added to the aged sol, and the pH of the reaction mixture is adjusted. The reaction mixture is poured into a mold, and then the mixture is gelated, aged, demolded, dried, and then thermally treated to remove organic substances. Hydroxy groups are eliminated and the gel is sintered. A high purity silica glass tube, substantially free of cracking after drying and having a low shrinking ratio can be obtained. Also, a large silica glass tube can be manufactured by this fabrication method.