Abstract: A method of producing glass fiber comprising: driving a bottomed hollow cylindrical rotor to rotate at high speed around a vertical rotary shaft, said rotor comprising a bottom, a peripheral wall and an annular flange, said peripheral wall being extended upwardly from an outer peripheral edge of the bottom and provided with a large number of fine holes, said annular flange extending inwardly from an upper edge of the peripheral wall; falling molten glass to the bottom of the rotor; and ejecting molten glass through said fine holes by centrifugal force generated by the high speed rotation of the rotor, to form the molten glass into filaments, and to produce glass fiber; characterized in that molten glass is made to fall at a position on the bottom, said position being apart from an inner edge of said annular flange by at least 10 mm or more, and apart from an inner surface of said peripheral wall by not more than 75 mm, the bottom having a large thickness at the position.

Abstract: It is therefore an object of the present invention to provide a method and an apparatus for continuously producing high quality glass fiber that shows excellent characteristics required to various glass fiber products in terms of fiber length, fiber quality and fiber distribution and, at the same time, that allows to prolong the service life of the rotating body, that improve the productivity, and that suppress any increase in the producing cost. An axial and/or circumferential rows of orificeless sections are provided in a peripheral wall of a hollow rotating body. Also, a gas flow is provided around a flame flow, and a compressed gas flow are also provided.

Abstract: A glass wool molded product comprising a layered body of glass wools is characterized in that the layered body does not contain any binder, the layered body is needle punched in a direction orthogonal to a longitudinal direction of the wools thereof, that the layered body is integrally formed, the wools have an average diameter of 3 to 7 ?m, and each of the wools has a length between 10 and 200 mm. Preferably, the molded product has a multilayer structure in a direction orthogonal to the longitudinal direction of the wools, and the average diameter of the fibers or wools of a first layer differ from each other. Preferably, a density of the second layer that of the second layer differ from each other.

Abstract: A glass composition improves the bio-solubility (solubility to physiological salt water), and is suitable for manufacturing inorganic fiber and a molded product of such inorganic fiber. The glass composition to be used for manufacturing inorganic fiber is characterized by containing SiO2 by 52 to 72 wt %, Al2O3 by less than 3 wt %, MgO by 0 to 7 wt %, CaO by 7.5 to 9.5 wt %, B2O3 by 0 to 12 wt, BaO by 0 to 4 wt %, SrO by 0 to 3.5 wt %, Na2O by 10 to 20.5 wt %, K2O by 0.5 to 4.0 wt % and P2O5 by 0 to 5 wt %. The raw material of the glass composition contains cathode ray tube glass and/or liquid crystal glass by 0 to 50 wt %.

Abstract: A mat-shaped thermal insulator made of inorganic fiber, wherein at least a part of inorganic fibers is built-up in a direction parallel to lateral surfaces of the insulator, and said insulator is formed by cutting a fibrous built-up article formed by building-up inorganic fibers, to form cut built-up articles, rotating at least one of the cut articles by an angle of 90 degrees in a direction perpendicular to a longitudinal direction, to form a rotated built-up article in which the inorganic fibers are built-up in a direction parallel to lateral sides of the cut article, and integrating the cut articles and/or the rotated article transversally in a direction perpendicular to cutting direction. Preferably, the lateral surfaces of the insulator are inclined. Still preferably, longitudinal cuts are formed on the lateral surfaces of the insulator so as to make the insulator partially compressible.

Abstract: A glass composition to be used for manufacturing inorganic fiber has a composition that entirely or partly eliminates the use of expensive boron oxide that is employed to lower the glass softening point and the viscosity. The glass composition contains 45 to 75 wt % of SiO2, 1 to 6 wt % of Al2O3, 0 to 4 wt % of MgO, 0 to 15 wt % of CaO, 0 to 6 wt % of B2O3, 0.1 to 10 wt % of BaO, 0.1 to 25 wt % of SrO, 5 to 17 wt % of Na2O, 0.5 to 10 wt % of K2O and 0 to 3.5 wt % of Fe2O3.

Abstract: A glass wool molded product comprising a layered body of glass wools is characterized in that the layered body does not contain any binder, the layered body is needle punched in a direction orthogonal to a longitudinal direction of the wools thereof, that the layered body is integrally formed, the wools have an average diameter of 3 to 7 ?m, and each of the wools has a length between 10 and 200 mm. Preferably, the molded product has a multilayer structure in a direction orthogonal to the longitudinal direction of the wools, and the average diameter of the fibers or wools of a first layer differ from each other. Preferably, a density of the second layer that of the second layer differ from each other.

Abstract: A method of producing glass fiber comprising: driving a bottomed hollow cylindrical rotor to rotate at high speed around a vertical rotary shaft, said rotor comprising a bottom, a peripheral wall and an annular flange, said peripheral wall being extended upwardly from an outer peripheral edge of the bottom and provided with a large number of fine holes, said annular flange extending inwardly from an upper edge of the peripheral wall; falling molten glass to the bottom of the rotor; and ejecting molten glass through said fine holes by centrifugal force generated by the high speed rotation of the rotor, to form the molten glass into filaments, and to produce glass fiber; characterized in that molten glass is made to fall at a position on the bottom, said position being apart from an inner edge of said annular flange by at least 10 mm or more, and apart from an inner surface of said peripheral wall by not more than 75 mm, the bottom having a large thickness at the position.

Abstract: A mat-shaped thermal insulator made of inorganic fiber, wherein at least a part of inorganic fibers is built-up in a direction parallel to lateral surfaces of the insulator, and said insulator is formed by cutting a fibrous built-up article formed by building-up inorganic fibers, to form cut built-up articles, rotating at least one of the cut articles by an angle of 90 degrees in a direction perpendicular to a longitudinal direction, to form a rotated built-up article in which the inorganic fibers are built-up in a direction parallel to lateral sides of the cut article, and integrating the cut articles and/or the rotated article transversally in a direction perpendicular to cutting direction. Preferably, the lateral surfaces of the insulator are inclined. Still preferably, longitudinal cuts are formed on the lateral surfaces of the insulator so as to make the insulator partially compressible.

Abstract: It is therefore an object of the present invention to provide a method and an apparatus for continuously producing high quality glass fiber that shows excellent characteristics required to various glass fiber products in terms of fiber length, fiber quality and fiber distribution and, at the same time, that allows to prolong the service life of the rotating body, that improve the productivity, and that suppress any increase in the producing cost. An axial and/or circumferential rows of orificeless sections are provided in a peripheral wall of a hollow rotating body. Also, a gas flow is provided around a flame flow, and a compressed gas flow are also provided.

Abstract: A glass composition improves the bio-solubility (solubility to physiological salt water), and is suitable for manufacturing inorganic fiber and a molded product of such inorganic fiber. The glass composition to be used for manufacturing inorganic fiber is characterized by containing SiO2 by 52 to 72 wt %, Al2O3 by less than 3 wt %, MgO by 0 to 7 wt %, CaO by 7.5 to 9.5 wt %, B2O3 by 0 to 12 wt, BaO by 0 to 4 wt %, SrO by 0 to 3.5 wt %, Na2O by 10 to 20.5 wt %, K2O by 0.5 to 4.0 wt % and P2O5 by 0 to 5 wt %. The raw material of the glass composition contains cathode ray tube glass and/or liquid crystal glass by 0 to 50 wt %.

Abstract: A process and an apparatus for producing glass fibers by centrifugal force are provided. Molten glass is fed into a hollow cylinder of rotating member which rotates at high speed by means of a driving device and is heated. The molten glass is ejected to an outside of a peripheral wall by centrifugal force generated by high speed rotation of the rotating member through orifices, each of which has different diameter, and which are provided alternately in a circumferential direction of the peripheral wall. A primary steam of molten glass is ejected. The primary streams is introduced into flame flow ejecting from drawing burners located at outside of the peripheral wall to form secondary fibers. A compressed gas flow is ejected to a direction at an acute angle through an ejecting outlet of an ejecting nozzle to collide the compressed fluid with the secondary fibers to thereby produce glass fibers by continuously.

Abstract: A glass composition to be used for manufacturing inorganic fiber has a composition that entirely or partly eliminates the use of expensive boron oxide that is employed to lower the glass softening point and the viscosity. The glass composition contains 45 to 75 wt % of SiO2, 1 to 6 wt % of Al2O3, 0 to 4 wt % of MgO, 0 to 15 wt % of CaO, 0 to 6 wt % of B2O3, 0.1 to 10 wt % of BaO, 0.1 to 25 wt % of SrO, 5 to 17 wt % of Na2O, 0.5 to 10 wt % of K2O and 0 to 3.5 wt % of Fe2O3.

Abstract: A thermal insulating and sound absorbing mat a mat cut to a predetermined length, upper and lower films covering lateral surfaces and front and rear end surfaces of the mat with respective minimal required lengths. The films are not damaged during the compression and packaging process nor torn by the internal pressure of the mat during the unpacking operation. The produced thermal insulating article has a structure that meets the requirements of JIS. Such thermal insulating articles can be manufactured by a highly productive method. Mats cut to a predetermined length are transferred sequentially side by side with an interval between adjacent mats such that the films have respective minimal required lengths. Each mat is covered by the films at the upper and lower surfaces and the lateral surfaces. Then, adjacent mats are stopped at a predetermined position with the interval, and are pushed downwardly at the oppositely disposed end surfaces to a predetermined height.

Abstract: A process for forming glass filaments by utilizing centrifugal force, in which compressed gas is injected from a position near an interior of a flame port frame of a fiberizing burner toward a throat portion of a discharge port of the burner at an acute angle relative to the direction of discharge of a flame stream from the discharge port, so that the compressed gas is mixed with combustion exhaust gas at an inlet portion of the throat portion, and the mixed gas is injected from the discharge port of the burner in a direction generally parallel to the direction of the generatrix of the outer peripheral surface of the peripheral wall, thereby forming primary filaments into fine secondary filaments.

Abstract: In a glass fiber forming unit including a hollow-cylinder-shaped rotating spinner having (a) a bottom, (b) a surrounding wall with a number of molten glass projecting orifices, and (c) an upper annular flange extending inwardly from the upper edge of the surrounding wall; and an attenuating blast burner with jet flame orifices for attenuating primary filaments formed at the tips of transition cones of molten glass projecting from the rotating spinner into secondary filaments, the improvement comprising the jet flame orifices in the attenuating blast burner being so positioned that, for each jet flame from each jet flame orifice, only an outer cone of flame is in contact with the lower portion of the outer surface of the surrounding wall of the hollow-cylinder-shaped rotating spinner where the speed of the outer cone of flame is such as to not break the transition cone of molten glass, and a heating burner disposed inside the upper annular flange of the hollow-cylinder-shaped rotating spinner for jetting a fla