Abstract: A silica sol-gel fabrication process is provided which allows improved control of the shrinkage that takes place during the drying of a gel body. In particular, the invention makes it possible to attain extremely low shrinkage through the completion of the drying stage, e.g., below 1% linear shrinkage, in relatively large sol-gel bodies of (dry weight) 1 kg or more, typically 10 kg or more, or even 40 kg or more, compared to the much higher shrinkages typically encountered. Specifically, use of a particular polymeric additive makes it possible for a gel body to experience linear shrinkage at least 55% less than an identical process without the polymeric additive.

Abstract: A method is provided for manufacturing a synthetic silica glass. The method includes the steps of maintaining a silica glass member, which is formed using a flame hydrolysis method and having an OH group concentration of about 500 ppm to about 1300 ppm, at a predetermined holding temperature for a predetermined period of time so as to substantially relax the structure of the silica glass member. The method further includes the step of subsequently cooling the silica glass member to a first predetermined temperature at a cooling rate of about 10 K/hour or less, and thereafter, cooling the silica glass member to a second predetermined temperature at a cooling rate of about 1 K/hour or less. The method further includes the step of further cooling the silica glass member to a third predetermined temperature at a cooling rate of about 10 K/hour or less.

Abstract: A system and method of cooling glassware molds by directing liquid coolant to the blank or blow mold halves of a glassware forming machine through an enclosed pivotal rotary union-type structure. A coolant manifold is carried by each pivotal mold arm, and communicates with coolant inlet and outlet ports at the lower end of each mold part. The manifold is connected by a floating shaft seal and a rotary union assembly and a crank arm to a coolant source and coolant return in the section box of the associated machine section. Each pivotal connection—i.e., between the section box and the crank arm, between the crank arm and the rotary union assembly, and between the rotary union assembly and the floating shaft seal—comprises a bi-directional rotary union for feeding liquid coolant to the manifold and mold parts, and returning coolant from the manifold and mold parts.

Abstract: A sol-gel process for fabricating bulk, germanium-doped silica bodies useful for a variety of applications, including core rods, substrate tubes, immediate overcladding, pumped fiber lasers, and planar waveguides, is provided. The process involves the steps of providing a dispersion of silica particles in an aqueous quaternary ammonium germanate solution—typically tetramethylammonium germanate, gelling the dispersion to provide a gel body, and drying, heat treating, and sintering the body to provide the germanium-doped silica glass.

Abstract: In a method of elongating a glass preform comprising the steps of holding both ends of the glass preform 1a with a first holding section 2 and a second holding section 3, respectively; moving the first holding section 2 and the second holding section 3 in a longitudinal direction of the glass preform 1a with the moving speed of the first holding section 2 faster than that of the second holding section 3 and, at the same time, heating and softening the glass preform 1a by a heating section 4 successively; and elongating the glass preform 1a by a tensile force applied thereto, so as to form an elongated body 1c; an electric furnace is employed in the heating section 4; and said method further comprising the steps of setting a reference value R1 with respect to an outside diameter at a specific position 1d in a tapered region 1b in the glass preform 1a in the process of elongating; acquiring an actually measured value R2 at the specific position 1d; and controlling the moving speed of the first holding section 2

Abstract: A manufacturing method for a glass product not having a rotatively symmetric body like an optical fiber fixing member but having a fine structure as of optical fiber engagement portions, to transfer the fine structure with a high precision without creating molding burrs, includes the steps of placing a glass material in a cavity defined by a lower mold, an upper mold, and a side mold, molding the glass material in the cavity with pressure into the glass product in so controlling that the glass material has a viscosity range of 106.5 to 109.

Abstract: The invention relates to a method for heating glass sheets to be tempered or heat-strengthened, in which method glass sheets are heated in a preheating furnace (1) by applying a hot-air blast and convection heating produced thereby to the opposite sides of a glass sheet and the preheated glass sheet is transferred from the preheating furnace (1) into a radiation heating furnace (2) for heating the glass sheet to a tempering temperature. During the convection heating of a glass sheet, the rotating speed of a hot-air fan (5) is increased while adjusting the heating effect of heating resistances (6) so as to maintain the temperature of blasted air substantially constant. Thus, the diminishing temperature difference between glass and air is compensated for by controlling the coefficient of heat transfer.

Abstract: A method for forming glass sheets is performed by a system (10) that includes a furnace (12) having a heating chamber (14) in which a topside transfer device (20) has a downwardly facing surface (22) to which vacuum and pressurized air are supplied to receive and support a heated glass sheet from a conveyor (16) without any direct contact. A forming station (24) located externally of the furnace has a vertically movable upper mold (28) whose temperature is not greater than 500° C. The upper mold (28) cooperates with a horizontally movable lower ring (34) that transfers the heated glass sheet from the topside transfer device (20) to the forming station under the control of a first actuator (40). A second actuator (42) moves the upper mold (28) downwardly to cooperate with the lower ring (34) in forming the glass sheet. The external forming station (24) includes heat loss reducing apparatus (43) for reducing heat loss of the hot glass sheet during the forming.

Abstract: A method of treating tobacco to reduce the content of, or prevent formation of, harmful nitrosamines which are normally found in tobacco is disclosed. The method includes the step of subjecting at least a portion of the plant, while the portion is uncured and in a state susceptible to having the amount of nitrosamines reduced or formation of nitrosamines arrested, to a controlled environment capable of providing a reduction in the amount of nitrosamines or prevention of the formation of nitrosamines, for a time sufficient to reduce the amount of or substantially prevent the formation of at least one nitrosamine, wherein the controlled environment is provided by controlling at least one of humidity, rate of temperature change, temperature, airflow, CO level, CO2 level, O2 level, and arrangement of the tobacco plant. Tobacco products and an apparatus for producing such tobacco products are also disclosed.

Abstract: A method for forming glass sheets is performed by a system (10) that includes a furnace (12) having a heating chamber (14) in which a vacuum platen (20) has a downwardly facing surface (22) to which a vacuum is supplied to support a heated glass sheet received from a conveyor (16). A forming station (24) located externally of the furnace has a vertically movable upper mold (28) whose temperature is not greater than 500° C. The upper mold (28) cooperates with a horizontally movable lower ring (34). A first actuator (39) moves the vacuum platen (20) vertically to transfer a heated glass sheet from the conveyor (16) to the lower ring (34) which is then moved by a second actuator (40) to the forming station (24). A third actuator (42) then moves the upper mold (28) downwardly to cooperate with the lower ring (34) in forming the glass sheet. The forming station (24) includes apparatus (43) for reducing heat loss of the glass sheet during the forming.

Abstract: A system for melting and delivering glass to a work area such as spinners for making fiberglass includes a melter with heaters so arranged that the “hot spot” in the molten glass is located away from the walls and corrosion sensitive parts so that the various elements of the melter wear out at substantially the same time. The system is further provided with a dual exhaust arrangement when the melter, conditioner and forehearth are located on the same floor of the plant, the first exhaust being at the juncture of the melter and conditioner, and the second being an alternating replacement for one of the heating/cooling orifices and mechanisms in the conditioner, so as to effectively limit the amount of corrosive volatiles reaching the forehearth.

Abstract: A method and apparatus are described for making an article such as the body of a needleless injector capsule, from a formable material, such as glass, the article having a cavity communicating with the exterior via an orifice. A blank having an open end is mounted on a first forming tool, and the open end is engaged by a second forming tool while an end region of the blank adjacent the open end is in a condition to permit it to be formed. One of the tools has a pin extending therefrom, and when the tools are brought together to form the end region into the desired shape the pin defines the orifice.

Abstract: A glassware forming mold that includes a body of heat conductive construction having a central portion with a forming surface for shaping molten glass and a peripheral portion spaced radially outwardly of the central portion. A plurality of coolant passages extend in a spaced array through the peripheral portion of the mold body, and liquid coolant is directed through such passages for extracting heat from the body by conduction from the forming surface. A plurality of openings extend axially into the body radially between at least some of the liquid coolant passages and the forming surface for retarding heat transfer from the forming surface to liquid coolant in the passages.

Abstract: A method of thermally treating a glass or glass-like material, preferably a glass sheet, without the use of conventional tunnel-type furnaces, to effect rapid heating of glass and glass-like materials from any initial temperature to any required temperature so that the glass sheet can be processed by shaping, bending, tempering, annealing, coating and floating of the glass sheet without cracking of the glass sheet is described. In the inventive method a microwave radiation with appropriate uniformity, frequency and power density is chosen so as to accomplish glass heating from any initial temperature to any required (e.g., softened) temperature in a selected short time while ensuring that the temperature distribution on the external surfaces and in the interior of the glass sheet that arises from microwave exposure is uniform enough to prevent the exposed glass sheet's internal thermal stress from exceeding its modulus of rupture, thereby avoiding glass breakage.

Abstract: The invention is a method of retaining selenium in a lass containing selenium by including a manganese compound and not including nitrates or nitrites routinely used in the industry to retain selenium. Particularly, a preferred embodiment involves manufacturing a gray soda-lime-silica glass composition including selenium as a colorant, the components of the gray soda-lime-silica glass have colorants consisting essentially of: greater than 0.9 to 1.9 wt. % total iron oxide as Fe2O3; 0.10 to 1.00 wt. % manganese compound as MnO2; 0.0010 to 0.0060 wt. % selenium as Se; 0.002 to 0.025 wt. % cobalt oxide as Co, and 0 to 1.0 wt. % titanium oxide as TiO2 which are combined and melted to make the glass composition. The glass composition has at 4.0 mm. thickness: 10 to 55% light transmittance using Illuminant A, less than 25% ultra violet transmittance, and less than 50% infra red transmittance.

Abstract: An apparatus and process for fabricating tubing used in the making of chalcogenide fibers. The apparatus features a three-sectioned melt/spin ampoule that allows for fabricating the chalcogenide tubing without introducing impurities and contaminants, in a self-contained apparatus.

Abstract: Apparatus for monitoring application of air through a dual-stage blowhead to blow mold a container includes a first solenoid valve for applying final blow air through the blowhead to a container in a mold and a second solenoid valve for applying finish cooling air through the blowhead around the finish of the container in the mold. Electronic circuitry is coupled to the first and second solenoid valves for detecting timing of application of first and second electrical valve control signals to the valves. Air pressure sensors are operatively coupled to the first and second solenoid valves for generating associated electrical signals indicative of timing of application of air by the first and second solenoid valves to the blowhead.

Abstract: A plurality of rollers provided at positions where a transferred glass plate is moved vertically to form a transferring plane formed by the primary rollers into a curved plane, and the curved plane is shifted in the transferring direction of the glass plate with the transfer of the glass plate to bend and shape the glass plate to have a predetermined curvature along the curved plane. Thus, there are obtainable a bending and shaping method and apparatus which does not require the exchanging of rollers in response to the type of glass plate being worked.

Abstract: A process for fabricating a face plate for a flat panel display such as a field emission cathode type display, the face plate having integral spacer support structures is disclosed. Also disclosed is a product made by the aforesaid process. The support structures are designed to be load bearing so as to prevent implosion of a planar, transparent face plate toward a parallel spaced-apart base plate when the space between the face plate and the base plate is sealed at the edges of the display to form a chamber, and the chamber is evacuated in the presence of atmospheric pressure outside the chamber. Unlike most spacer support structures proposed for such flat panel displays, the support structures are made from the same material as the substrate from which the face plate is fabricated. For a preferred embodiment of the process, a perforated laminar template is sealably sandwiched between a laminar silicate glass substrate and a manifold block to form a temporary sandwich assembly.

Abstract: The invention relates to an air output unit in connection with a tempering station in a tempering plant for glass panels, and to a method for manufacturing the unit. An equipment bay (3) has its walls (32), roof (33), and floor (31) designed and dimensioned as a shipping container, wherein air output equipment (4) is set up and secured prior to shipping to a working site. Since the fan room enclosing an air output unit functions at the same time as a shipping container for the air output unit, the repeated loading and unloading of air output equipment is avoided. The workload required for shipping and assembling is substantially reduced.