| 摘要 |
<p>Uniaxially-oriented polymer film is passed across a driven roller whose surface has a series of offset sharp stiff protrusions arranged in a uniform pattern. The film is pressed into contact with the protrusions so that they penetrate it and the surface speed of the driven roller is arranged at 1.5 to 20 times the speed of the film. Comprises an extruder to produce the film which is stretched at a draw ratio of between 6 and 10 to 1 and then passed over the roller with the protrusion, which may be formed by winding card clothing with stiff sharp points about a drum. The film may be pressed onto the protusion by a dtiff bristled roller brush.</p> |
