Abstract: Provided is a thermal molding method for producing a thermally molded article having excellent abrasion resistance at its melt-fused part. Polyamide 6 and a copolyester are prepared separately. The copolyester contains terephthalic acid, ethylene glycol, and 1,4-butanediol as copolymerization units. The copolyester may further contain ?-caprolactone and/or diethylene glycol as a copolymerization unit. A multifilament yarn in which core-sheath type composite filaments each containing a core component and a sheath component at a ratio of 1 to 4:1 by mass are bundled is produced by a composite melt-spinning method using the polyamide 6 as the core component and the copolyester as the sheath component. Using the multifilament yarn, a product of filaments is produced by weaving, knitting, knitting and braiding, or braiding.