| 摘要 |
PURPOSE: To obtain a transom board with an enhanced durability by the use of core material being hardened and foamed with foamable polyurethane resin liquid impregnated into glass fiber oriented in a constant direction. superimposing the core materials in a parallel crossed relationship in the fiber direction, and then integrating them under compression with synthetic resin impregnated-mats lying among respective core materials. CONSTITUTION: Core material l is cut into a transom shape. and the fiber direction of the core material l is put into a lateral direction for applying a treatment liquid over the entire surface, then glass mats 4.6 with polyester resin impregnated therein are press-bonded on both surfaces. An intermediate core material 2 is put thereon in a manner such that the fiber direction is in the longitudinal direction, and they are stuck with each other through the application of the same liquid on the surface being in contact with the mat 4. The same liquid is applied on the upper surface of the core material 2, and a glass fiber mat 5 is put thereon, and after the application of the same liquid is done on the upper surface, the same liquid is applied on the lower surface of a core material 3 for the upper surface and it is put in such a manner that the fiber direction is in a lateral direction, following this, a glass fiber mat 7 is placed on the upper surface of the core material 3 to subsequently be stuck with each other. The rear and front surfaces of a plywood obtained in this manner is coated with gel coat resin 8, 9, and they are subjected heat press-bonding process to thereby be integrated in use of a mold. |
