US Patent 7674510 Fiber fabric and composite material

A fiber fabric includes a first fiber layer formed of a plurality of first fiber bundles, a second fiber layer formed of a plurality of second fiber bundles, a retaining thread group formed of a plurality of retaining threads, and a constraint thread group formed of a plurality of constraint threads. The first fiber layer is laminated in adjacent to the second fiber layer. The first fiber bundles diagonally intersect the second fiber bundles at an angle of 45 degrees. Accordingly, it is possible to improve a production efficiency of an overlapped sheet which gives excellent moldability and a strength, and has an increased thickness by overlapping the fiber fabrics.