| 摘要 |
PROBLEM TO BE SOLVED: To provide a wood screw capable of preventing a raised part from being generated on a surface of a molded product when the screw is screwed in the molded product of a mixture of a plastic waste and a wooden chip. SOLUTION: A tapered shaft part 3 of <=30 deg. in taper angle is provided on a tip of a straight shaft part 1. The lead angle of a preceding thread 4 provided over the tip of the straight shaft part 1 from the tip of the tapered shaft part 3 is set to be larger than the lead angle of a succeeding thread 5 provided on the straight shaft part 1, the thread angle of the preceding thread 4 is set to be smaller than that of the succeeding thread 5, and a raised part is prevented from being generated on a surface of a molded product in which the screw is screwed by the difference in the lead angle and the thread angle between the preceding thread 4 and the succeeding thread 5. |
