To enhance the whole strength of a core material by enhancing the shear strength thereof and to also flexibly correspond to the formation of a curved surface by a slit.
This laminated material has a three-layered structure consisting of a core material 2 and the hand lay-up plate materials 3A, 3B bonded to the upper and rear surfaces of the core material 2 and the core material 2 is formed by bonding blocks 4 made of a foamed resin having the same thickness and cut into a predetermined size through bonding glass cloths 7 and a resin putty material and a plurality of slits 5a, 5b formed to the blocks 4 made of the foamed resin in the thickness direction thereof at a constant interval are filled with a resin putty agent and the hand lay-up plate materials 3A, 3B are formed by laminating a plurality of resin impregnated glass cloths to mold them.
HAMADA KENICHI
IWATA SETSUO
