| 摘要 |
594,302. Plywood panels. BAILEY, W. C. Oct. 20, 1944, No. 20390. [Class 145 (ii)] In a plywood panel in which one face ply 1 has grooves or striations 5 lengthwise of the grain, each groove being of substantially the same depth throughout its length, but adjacent grooves being of different depth, as described in Specification 553,476, the face ply 1 before grooving is thicker than the opposite face ply 2 so that, when grooved, its average thickness indicated by the line 4 is substantially equal to that of the ungrooved face ply 2 whereby the stresses in the two face plies are equalized and the tendency of the panel to curl is eliminated. The core ply 3 is preferably thicker than either of the face plies 1, 2. |
