PROBLEM TO BE SOLVED: To provide a nonwoven fabric that has at least a certain level of weather resistance, is hardly deteriorated with moisture and heat, and can be suitably used in an agricultural field or a civil engineering field.SOLUTION: The continuous fiber nonwoven fabric is a nonwoven fabric composed of a core-sheath type composite continuous fiber. The fiber has a core part made from a polylactic acid-based polymer and a sheath part made from a polyolefin-based polymer. The melting point of the polymer in the sheath part is lower than the melting point of the polymer in the core part by 30°C or more. The fiber has a single fiber fineness of 13-20 decitex. The nonwoven fabric has a thermocompression bonded part formed therein. Fibers of the nonwoven fabric are mutually integrated with the thermocompression bonded part. The nonwoven fabric has a strength retention of 50% or more after a wet heat resistance test (400 hours) both in a machine direction and in a direction orthogonal to the machine direction, and a strength retention of 50% or more after a weather resistance test (300 hours) both in a machine direction and in a direction orthogonal to the machine direction.SELECTED DRAWING: NoneCOPYRIGHT: (C)2017,JPO&INPIT【課題】一定以上の耐候性を有し、かつ湿熱劣化しにくく、農業分野や土木分野に好適に用いることができる不織布を提供する。【解決手段】 芯鞘型複合連続繊維により構成される不織布であり、該繊維は、芯部がポリ乳酸系重合体、鞘部がポリオレフィン系重合体からなり、鞘部の重合体の融点が芯部の重合体の融点よりも30℃以上低く、該繊維の単繊維繊度が13~20デシテックスであり、不織布に熱圧着部が形成されてなり、不織布の繊維同士は熱圧着部により一体化しており、不織布は、耐湿熱試験(400時間)における強力保持率が機械方向および機械方向に直交する方向ともに50%以上、かつ耐候性試験(300時間)における強力保持率が機械方向および機械方向に直交する方向ともに50%以上である連続繊維不織布。【選択図】なし
