Reinforced substrate for composite material, composite material, and method for manufacturing reinforced substrate for composite material

1. A reinforced substrate used for molding a composite material, the reinforced substrate comprising:

a first region including reinforcing fibers extending in a fiber direction that is aligned in a single direction;

a second region including the reinforcing fibers aligned in the same direction as the fiber direction and being thinner than the first region;

auxiliary fibers laminated on the reinforcing fibers so as to extend in a direction that intersects the fiber direction, and joined to at least a portion of the reinforcing fibers to hold the reinforcing fibers; and

a stitching yarn that stitches and joins the laminated auxiliary and reinforcing fibers together;

the first region and the second region being lined up in alternating fashion in a plane along a direction intersecting the fiber direction, the reinforcing fibers of the first region have a first tow, and the reinforcing fibers of the second region have a second tow, the first tow having a fiber count of 40,000 or more and the second tow having a fiber count of 24,000 or less.

2. The reinforced substrate according to claim 1 , wherein

the second tow of the second region has a fiber count of 12,000 to 24,000.

3. The reinforced substrate according to claim 1 , wherein

the first region and the second region are formed so that one surface of each of the first and second regions is orthogonal to a thickness direction and both surfaces lie in the same plane.

4. The reinforced substrate according to claim 1 , wherein

the auxiliary fibers have a lower modulus of elasticity than do the reinforcing fibers.

5. The reinforced substrate according to claim 1 , wherein

the auxiliary fibers have a higher tensile elongation at break than do the reinforcing fibers.