| abstract |
A liquid polymer plane layer (38) is produced which is mechanically quasi-isotropic, by superposing two biaxially oriented layers. This gives a laminate with two thin parts with an external surface oriented in the same direction, and a relatively thick internal part. Said layer is produced by passing a polymer through a series of three tubular rotors (30). Said rotors are concentric and have surfaces defining internal and external annular polymer flow channels. The rotors can rotate either in the direction of flow or in the opposite direction. In another embodiment, the layer is obtained by using a matrix of the groove type (90) through which the polymer flows, in one of the possible directions, while a moving strip (91) passes continuously in a transverse direction. . Said ordered polymer layers are useful for the manufacture of printed circuit boards. |