Tape-shaped prepreg and a method for production thereof

A tape-shaped prepreg comprising unidirectionally oriented reinforcing fibers and a thermoplastic resin composition, wherein the tape-shaped prepreg has

• an arithmetic average roughness (Ra) of 0.1 to 10 μm in a direction perpendicular to the orientation direction of the reinforcing fibers, as measured according to JIS B 0601:
• 2013, and
• a warpage rate of 5% or less as determined by the procedure specified in (i) to (iii) below:
• (i) a test piece of the above tape-shaped prepreg having a length of 100 mm is placed in the fiber orientation direction on a plane in such manner that the end portions curl upward,
• (ii) the vertical distance from the highest position at the right end of the curled tape to the plane, which is denoted by a, and the vertical distance from the highest position at the left end to the plane, which is denoted by b, are measured and the arithmetic average of a and b is calculated, which is defined as the warpage distance, and
• (iii) the warpage rate is calculated based on the following equation:
• warpage rate (%)=warpage distance (mm)/100 (mm)×100,
• wherein
• the tape-shaped prepreg has a thickness of 0.20 to 15 mm and
• the tape-shaped prepreg exhibits a waviness curve having a maximum cross-sectional height (Wt) of 80 μm or less in a direction perpendicular to the orientation direction of the reinforcing fibers, as measured according to JIS B 0601:
• 2013.