Abstract: The invention provides a nozzle tip for manufacturing a glass fiber having a deformed cross-section which is of a large deformation ratio in the cross-section. A plurality of projected edges are provided to extend downwardly from the distal end of a nozzle tip at its outer periphery. Molten glass coming out of an orifice is separated at an outlet of the orifice into a flow descending from the orifice center and flows descending along inner walls of the projected edges, and the flow descending from the orifice center is attracted toward the flows descending along the inner walls of the projected edges. As a result, a glass fiber having a deformed cross-section is produced which is protruding in its portions corresponding to the projected edges. The cross-section of the glass fiber produced by using the present nozzle tip has a deformation ratio not less than 2.3.

Abstract: A nozzle plate for spinning glass fiber including a flat plate portion and a multiplicity of nozzles projecting from the flat plate portion. Each of the nozzles comprises a greater diameter portion located at its flat plate portion side and a smaller diameter portion located at its tip side. The smaller diameter portion has an inner diameter of 0.3 mm to 1.0 mm and a length of 0.5 mm to 2.0 mm, and the greater diameter portion has an inner diameter of 1.1 mm to 2.5 mm, and the length of the nozzle projecting from the flat plate portion is in range of 4.0 mm to 6.0 mm. By use of this nozzle plate for spining glass fiber, a fine glass fiber having a diameter smaller than 3 .mu.m can be manufactured in a stable manner.

Abstract: A flat glass fiber strand comprises a multiplicity of glass filaments having a non-circular cross-sectional shape with the ratio between its maximum and minimum dimensions being between 1.2:1 and 3:1, and which are gathered in such a manner that one dimension of the cross-section of each extends in parallel with the same dimension of the other filaments. This flat glass fiber strand is manufactured by discharging molten glass under high pressure from a multiplicity of nozzles which are shaped in the form of bores having non-circular cross-sectional shape with the ratio between its maximum and minimum dimensions being between 1.5:1 and 6:1 so as to form a multiplicity of filaments of non-circular cross-sectional shape which are then gathered and wound.

Abstract: A method of producing a glass fiber strand in which a plurality of molten glass filaments spun from adjacent nozzle ports in a nozzle plate are adjoined to one another so as to form a single glass fiber having a non-circular cross-sectional shapes such as oval, elliptic, cocoon-shaped and polygonal shapes. The method can employ a nozzle plate provided in the underside thereof with a plurality of recesses in each of which a plurality of nozzle ports are opened, so that the molten glass filaments from these nozzle ports are adjoined to each other so as to form the single glass fiber having a non-circular cross-section.