| 摘要 |
<p>Method includes holding a layer of polyurethane foam against the heated plate of a press to form a skin for applying an adhesive coating for abrasive powder. The adhesive is mixed with an acetone base and allowed to stand for about twelve hours before being applied. The layer is passed through an adhesive applicator machine, and the powder is distributed from a vibratory hopper. The layer is suspended to eliminate excess powder and it is dried, then passed through another applicator machine to receive a second adhesive coating. It is dried against and allowed to stand before being out into sections. Black smoke can be used during the first adhesive coating for obtaining a uniform colour.</p> |
