The aim of this study was to fabricate "flexible" composite materials. The materials used were 2.5 dimensinal warp knitted fabrics by aramid fiber and three kinds of resins. One was a conventional unsaturated polyester resin. The others were epoxy resin a conventional one and modified one which possess high flexibility.
　Three point bending test and vibration test were carried ont to evaluate mechanical and damping properties. Firstly basic mechanical properties of 2.5 D warp knitted fabric reinforced unsaturated poly-ester resin were presented.
　The bending strength of resin hybrid composites decreased up to 50% compared with, conventional epoxy composites nevertheless high flexibility materials were used.
　From the results of damping test resin hybrid composites possess extremly high loss factor. "Flexible" composites were able to fabri-cate by usiug knitted fabrics and resin hybrid lamination.

DESCENTE SPORTS SCIENCE Vol.14/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE