Abstract: A glass substrate for use in an information recording medium is manufactured by polishing a surface of a disc-shaped glass substrate and then performing texture processing on the surface. The texture processing includes the steps of forming lines of texture on the surface of the glass substrate extending along a circumferential direction of the glass substrate by performing a mechanical texture formation method in which the surface of the glass substrate is supplied with an abrasive slurry while an abrasive member slidably contacts the surface, and correcting the shape of the texture by removing burrs formed on the texture during the formation of the texture. The correction of the shape of the texture is performed by using a correcting pad made of foam of a synthetic resin having a 100% modulus of 3 to 40 MPa and scrubbing the surface of the glass substrate with the correcting pad in a direction intersecting the direction in which the texture extends.

Abstract: Provided is a process for bleaching pulp with ozone. The process involves preparing a slurry of cellulosic pulp having a consistency in fibers of from 1-5 weight %. Such a low consistency slurry is then mixed with ozone under high shear conditions. The ozone is then maintained in contact with the cellulosic fibers to effect bleaching of the fibers. The present process offers the advantages of bleaching using a low consistency slurry, with the added advantages of employing ozone.

Abstract: In order to avoid deposition of evaporating alkali compounds on an inner surface of a hollow glass body during thermal processing to form a glass container from the hollow glass body, an overpressure is provided in the hollow glass body during the thermal processing. Either rinsing the hollow glass body with a gas, such as air, or at least partially closing the glass body at one end so that sufficiently rapid pressure equilibration is avoided, can provide this overpressure. The glass containers made by these methods are especially suited for food or pharmaceuticals because they have a reduced alkali release from their inner surfaces, for example at most about 2.0 mg/l sodium oxide.

Abstract: A method of manufacturing a glass substrate for a magnetic disk. The method includes the step of scrub-etching the glass substrate using a pad in the presence of an acid treatment solution. As the acid treatment solution, hydrofluoric acid is used in a range of 0.01 to 1 wt %. The scrub-etching step is performed at temperatures ranging from 5 to 60° C. for 1 second to 300 seconds. The method produces a substrate that is substantially free of asperity.

Abstract: A process for the vertical drawing of glass tubes, optionally with safety strips, sealed bottoms, and, if desired, a pressure equalizing aperture wherein specific tube lengths are severed in succession from a continuous glass tube rod. The glass tube rod, closed at its beginning and exiting through a feeder head from a vessel which contains molten glass, is introduced, being under atmospheric pressure in the interior of the glass tube rod, in the still plastic condition into a pressure tank located downstream of the feeder head where the glass tube rod is exposed to a defined pressure and is conducted on a non-plastic condition out of the pressure tank by drawing. Thereafter, by heating the glass tube rod at an interval after leaving the pressure tank, a specific tube length is severed from the continuous glass tube rod essentially simultaneously with the formation of bottoms that seal the melted-off tube length and the continuous glass tube rod.

Abstract: A blow-pipe 1 with an upper end 2 shaped to retain a working amount of molten glass is vertically movable from beneath the surface of molten glass 9 in a furnace to an upper position within orifice 10a of cover plate 10 and just below a cylindrical guide tube 11. Upward movement brings the blow-pipe generally into a hotter environment, expands the internal air and thus provides an initial bubble at the blow-pipe end. This is progressively expanded into the guide tube, preferably by two-stage air supply at different pressures, to produce a constrained glass bubble, of a few microns thickness.

Abstract: The alkali content of the inner surface of glass tubing is reduced by introducing an acidic gas into the glass tubing at the hot draw stage to react with alkali ions on the inner surface of the glass.

Abstract: A continuous process for the manufacture of cellular ceramic product. Ceramic feed material is transported successively through a preheat kiln section, through a foaming section whereat foaming agent mixed with the ceramic feed material is activated, and into a drawing kiln section. An elongate hollow product can be formed by drawing the foamed ceramic while soft around and past a hollow mandrel to form an elongate hollow cylindrical member.

Abstract: A continuous process for the manufacture of cellular ceramic product. Ceramic feed material is transported successively through a preheat kiln section, through a foaming section whereat foaming agent mixed with the ceramic feed material is activated, and into a drawing kiln section. An elongate hollow product can be formed by drawing the foamed ceramic while soft around and past a hollow mandrel to form an elongate hollow cylindrical member.

Abstract: A method of making glass tubes in which forced cooling of the tube is effected from the inside thereof in an annealing section of a tube fabricating plant.