Random mat and fiber-reinforced composite material shaped product

A process for producing a random mat comprising a reinforcing-fiber mat and a thermoplastic resin, the process comprising:

• widening a reinforcing fiber strand;
• and the following steps (1) to (4):
• (1) cutting off reinforcing fibers from the reinforcing fiber strand;
• (2) introducing the cut reinforcing fibers into a tube, conveying the reinforcing fibers in the tube with air and spraying the reinforcing fibers from the tube;
• (3) fixing the sprayed reinforcing fibers to obtain a reinforcing-fiber mat;
• and
• (4) adding a thermoplastic resin to the reinforcing-fiber mat to obtain a random mat, wherein
• the reinforcing fibers have an average fiber length of 3 to 100 mm;
• the weight-average fiber thickness of the reinforcing fibers is 0.01 mm or more and 0.30 mm or less;
• fiber axes of the reinforcing fibers are substantially parallel to a plane of the random mat;
• the reinforcing fibers are randomly dispersed in the plane of the random mat;
• and
• the reinforcing fibers satisfy the following i) to iii):
• i) the reinforcing fibers have a weight-average fiber width (Ww) which satisfies the following equation (1):
• 0 mm<Ww<2.8 mm (1);
• ii) the reinforcing fibers have an average-fiber-width dispersion ratio (Ww/Wn), which is defined as a ratio of the weight-average fiber width (Ww) to a number-average fiber width (Wn), of more than 1.00 and 2.00 or less;
• and
• iii) the reinforcing fibers have a weight-average fiber thickness which is smaller than the weight-average fiber width (Ww).