| 摘要 |
PURPOSE:To obtain polyurethane foam slab with flat top surface by a method in which the polyurethane foaming stock solution agitated and mixed is poured in a foaming tank, and at the arbitrary position from the point where the foaming rise has attained to a specified rate to the point immediately before the finish of the foaming rise, the weight with flat rear surface is put on said foaming solution from above in the foaming tank, whereby the foaming rise is allowed to finish. CONSTITUTION:A foaming reaction of polyurethane stock solution and the foaming rise due to said reaction progress in a foaming tank 11. After a while, at the position where e.g. about 70% foaming rise progresses, a weight placed at upper part in the foaming tank 11 is dropped down. As the result, the rise of the foaming stock solution further advances, while said solution pushes up the weight 17, and the desired polyurethane foam slab 19 is obtained. Consequently, the polyurethane foam with flat top surface may be obtained whereby it is unnecessary to cut a protruded top part into a prescribed shape. Therefore, the yield of the slab is improved, and the cutting process may be omitted. |
