| 摘要 |
PROBLEM TO BE SOLVED: To provide a fastener for a weed prevention sheet, excellent in durability and fixing strength with ground.SOLUTION: This fastener of a weed prevention sheet includes a head part fitting with a rotary tool, and a column like shaft part extending from the center of lower surface of the head part. The shaft part has a 5 to 15 mm diameter, a sharp tip end with 100 to 500 mm length in an axial direction, spiral screw threads formed at its outer circumference from the tip end of the shaft part to the position at or more than 1/2 of shaft directional length, and a part where the screw threads are not formed from the lower surface of the head part up to a position apart by ≥5 mm from the head part. A diameter (d1) of inscribed circle of the head part is larger than the diameter (d2) of the shaft part, the interval of the adjacent screw threads in the shaft direction is 3 to 10 mm. the height of the screw threads is 1 to 3 mm, the fastener is formed of iron, and a hot dipping plated layer of a metal having a larger ionization tendency than that of the iron is formed on the iron surface. |
