| 摘要 |
PURPOSE:To provide the surface of the board with compactness and improve the mechanical strength of the board itself by a method wherein fine fibers are distributed in the front and rear layers of the board while bulk fibers, whose particle size is increased toward the center layer of the same board, are distributed in the center layer. CONSTITUTION:The fibers, coated with adhesive, are thrown into a hopper 3 and are passed through the clearances of fluffers 4 of several stages to prevent re- entanglement of the fibers after separating them into fiber units mechanically, then, are dropped and suspended. Thereafter, the suspended fibers are blown by horizontal ventilating airflow from a fan 5, then, the bulk fibers (b) collide against nearer buffle plates 6 before the fan and the kinetic energy of horizontal plane is absorbed, then, they drop naturally while fine fibers (a) are generated by the effect of absorbers 7. The fine fibers are ascended by ascending airflow between respective buffle plates, the finer fibers pass between the upper buffle plates and are sent to farer distance, thereafter, are dropped on a conveyer. In this case, a mat (m), in which the fine fibers (a) are located at the lowest layer and the particle size is increased gradually toward the upper surface while the bulk fibers (b) are distributed in the uppermost layer, may be obtained and the mat is provided with the specified particle size gradient in the direction of the thickness thereof. |
