PROBLEM TO BE SOLVED: To provide a weed-preventing sheet with light-shielding property having superior weather-resistant property, mechanical property, impermeability, and penetration preventing property for preventing hard and acute shoots of weeds from penetrating the weed-preventing sheet.SOLUTION: The weed-preventing sheet comprises at least 5 layers of a surface layer (a) containing inorganic particles or a synthetic resin containing the inorganic particles, an improved asphalt layer (b), a base material layer (c), the improved asphalt layer (d), and a rear surface layer (e) containing a synthetic resin or the synthetic resin containing the inorganic particles, in this order. The base material layer (c) includes a base material A which is at least one material selected from a group consisting of an woven fabric, a knitted fabric and an unwoven fabric, and a base material B having scrim. The woven fabric, the knitted fabric, and the unwoven fabric of the base material A include a fiber having a core-in-sheath structure including a core part and a sheath part of which (1) the core part is a fiber having a melting point of 200°C or above, and (2) the sheath part is a resin having a melting point of 200°C or above. The synthetic resin of the rear surface layer (e) is a hard synthetic resin.COPYRIGHT: (C)2009,JPO&INPIT【課題】遮光性を有し、耐候性、機械的特性、不透水性に優れ、さらに硬く鋭い雑草の芽の防草シートに対する貫通防止性に優れる防草シートを提供する。【解決手段】(a)無機質粒子または無機質粒子を含有する合成樹脂を含む表面層、(b)改質アスファルト層、(c)基材層、(d)改質アスファルト層および(e)合成樹脂または無機質粒子を含有する合成樹脂を含む裏面層の少なくとも5層をこの順で積層した防草シートであって、(c)基材層が、織布、編み布および不織布からなる群より選ばれる少なくとも一つである基材Aと、スクリムを有する基材Bとを含み、基材Aの織布、編み布および不織布が、芯部と鞘部とを有する芯鞘構造の繊維を含み、(1)芯部が融点200℃以上の繊維および(2)鞘部が融点200℃以上の樹脂であり、(e)裏面層の合成樹脂が硬質合成樹脂である防草シートである。【選択図】図1
