A reinforcing material is disclosed that includes coated glass flakes and coated glass strands. When the total amount of a glycidyl group-including resin and aminosilane contained in the coatings of the coated glass flakes corresponds to 100% by mass, the amount of the resin is 30% to 95% by mass. When the total amount of a glycidyl group-including resin, aminosilane, and a urethane resin contained in the coatings of the coated glass strands corresponds to 100% by mass, the amount of the glycidyl group-including resin is 10% to 90% by mass, the amount of the aminosilane is 0.1% to 40% by mass, and the amount of the urethane resin is 1% to 50% by mass. Both the coated glass flakes and the coated glass strands have an ignition loss of 0.1% to 2.0% by mass measured pursuant to JIS R3420 (2013).

A resin composition for the secondary coating of an optical fiber is a resin composition containing a non-reactive urethane compound having a number average molecular weight of 10000 or more and 50000 or less, a photopolymerizable compound, and a photopolymerization initiator, the content of the non-reactive urethane compound is 0.05 parts by mass or more and 5 parts by mass or less based on the total amount of the resin composition, and the non-reactive urethane compound is a reaction product of a polyol having a number average molecular weight of 8000 or more and 20000 or less, a diisocyanate, and a compound having active hydrogen.

A resin composition for the secondary coating of an optical fiber is a resin composition containing a non-reactive urethane compound having a number average molecular weight of 10000 or more and 50000 or less, a photopolymerizable compound, and a photopolymerization initiator, the content of the non-reactive urethane compound is 0.05 parts by mass or more and 5 parts by mass or less based on the total amount of the resin composition, and the non-reactive urethane compound is a reaction product of a polyol having a number average molecular weight of 8000 or more and 20000 or less, a diisocyanate, and a compound having active hydrogen.

A filament winding method and system without needing a resin dip bath are disclosed. The method comprises feeding a fiber band of a plurality of fibers onto a mandrel without dipping the fibers in a resin bath, and applying a resin onto the fiber band at or about where the fiber band contacts the mandrel or applied directly to the fiber band and then wound onto the mandrel so that the resin is between the mandrel and the fiber band at the point of contact. In some embodiments, the resin can be sprayed onto the fibers and in other embodiments, the resin can be delivered in at least one layer onto the fiber band that is then impregnated into the fiber band as the fiber band wraps around the mandrel. The fiber can comprise carbon fiber, basalt fiber, glass fibers, Kevlar fiber, polyester fiber, other fibers, or a combination thereof.

The present invention relates to storage-stable prepregs (preimpregnated fibers) on the basis of lightfast, low-viscous polyurethane systems with an increased characteristic number and flat fiber composite components (molded bodies; composite compounds) produced therefrom, which can be obtained by methods of impregnation of, for example, woven fabrics and laid scrims, and to a method for the production thereof.

A method for manufacturing an optical fiber ribbon includes: forming a colored layer on to each of a plurality of optical fibers and forming an optical fiber ribbon by curing a connecting material applied to a surface of the colored layer of each of the optical fibers to form connection parts that connect adjacent ones of the optical fibers. Forming the colored layer further includes: applying a coloring agent to the optical fibers and curing the coloring agent such that uncured resin remains on the surface of the colored layer. Forming the optical fiber ribbon further includes: applying the connecting material to the surface with the uncured resin and curing the connecting material and the uncured resin on the surface of the colored layer.

A method for manufacturing an optical fiber ribbon includes: forming a colored layer on to each of a plurality of optical fibers and forming an optical fiber ribbon by curing a connecting material applied to a surface of the colored layer of each of the optical fibers to form connection parts that connect adjacent ones of the optical fibers. Forming the colored layer further includes: applying a coloring agent to the optical fibers and curing the coloring agent such that uncured resin remains on the surface of the colored layer. Forming the optical fiber ribbon further includes: applying the connecting material to the surface with the uncured resin and curing the connecting material and the uncured resin on the surface of the colored layer.

An optical fiber includes a glass fiber and a coating resin layer with which the glass fiber is covered, wherein the coating resin layer includes tin and a cured ultraviolet curable resin composition containing 2,4,6-trimethylbenzoyldiphenyl phosphine as a photoinitiator, a percentage of uncured components having a molecular weight of 1000 or less included in the coating resin layer is 15% by mass or less, and a fraction of an amount of a phosphorus-tin complex with respect to an amount of hydrocarbon on the surface of coating resin layer is 1000 ppm or less.

A method for manufacturing an optical fiber is a method for manufacturing an optical fiber including a glass fiber, and a coating resin layer that coats the glass fiber by being in contact with the glass fiber. The method includes a step of increasing a dissolved oxygen concentration in an ultraviolet ray curable resin composition, a step of applying the ultraviolet ray curable resin composition, in which the dissolved oxygen concentration is increased, onto the glass fiber, and a step of curing the ultraviolet ray curable resin composition by irradiating the ultraviolet ray curable resin composition that is applied onto the glass fiber with an ultraviolet ray.

A method for manufacturing an optical fiber is a method for manufacturing an optical fiber including a glass fiber, and a coating resin layer that coats the glass fiber by being in contact with the glass fiber. The method includes a step of increasing a dissolved oxygen concentration in an ultraviolet ray curable resin composition, a step of applying the ultraviolet ray curable resin composition, in which the dissolved oxygen concentration is increased, onto the glass fiber, and a step of curing the ultraviolet ray curable resin composition by irradiating the ultraviolet ray curable resin composition that is applied onto the glass fiber with an ultraviolet ray.