Production method for separated fiber bundle, separated fiber bundle, fiber-reinforced resin molding material using separated fiber bundle, and production method for fiber-reinforced resin molding material using separated fiber bundle

Abstract

Provided is a production method for a separated fiber bundle. The production method is characterized by including at least [A] a partial separation step for obtaining a partially separated fiber bundle that comprises separation-processed parts and not-separation-processed parts that are alternately formed along the long direction of a fiber bundle that comprises a plurality of single threads, wherein the separation-processed parts comprise a plurality of separated bundles, and [B] a cutting step for cutting along the long direction of the fiber bundle at the not-separation-processed parts of the partially separated fiber bundle formed during step [A]. A separated fiber bundle produced by means of said method, a fiber-reinforced resin molding material that uses the separated fiber bundle, and a production method for the fiber-reinforced resin molding material that uses the separated fiber bundle. The present invention can keep cutting processing to a minimum during the cutting step [B]and, in comparison with conventional techniques in which separation processing is performed by using a slitter or the like to abruptly and continuously make vertical slits in a fiber bundle that comprises a large tow, can reduce the risk of process trouble and the frequency with which a cutting blade is replaced and greatly improve productivity.

Description

technical field [0001] The present invention relates to a method for producing a split fiber bundle and a split fiber bundle, and more specifically, the present invention relates to a method for manufacturing a split fiber bundle with high bundle shape retention and a split fiber bundle manufactured by the method, and A fiber-reinforced resin molding material using the split fiber bundle and a method for producing the split fiber bundle, which has high bundle shape retention, is capable of disentangling the previously unimagined fiber bundle without causing breakage. Inexpensive large tows that are thin and have a large number of filaments are subjected to partial fiber splitting that can be continuously split, and then the partially split fiber bundles are processed into split fiber bundles that are completely split. Background technique [0002] Molding in which a desired shape is produced by heating and press molding using a molding material formed of discontinuous reinfo...

AI Technical Summary

Problems solved by technology

However, this method involves forming a flow path in the fiber bundle to facilitate resin impregnation, and it is essentially a different technology from fiber splitting of fiber bundles such as large tows.

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