| 摘要 |
PURPOSE:To obtain the titled prepreg that is very thin, contains a large quantity of resin, is provided with a flat surface and is suitable for multilayer printed wire board by impregnating the base material with varnish, heating, drying the resin and then cooling the base material. CONSTITUTION:Base material 1 (preferably, glass cloth) is dipped in a varnish tank 3 and is impregnated with the varnish 2 composed of thermosetting resin such as epoxy resin etc. Then, said base material 1 is sent from the inlet port 4a into a vertical dryer 4 and heated and dried at, for example, 130-150 deg.C. After breeze is given directly in front of the outlet 4b the base material is cooled gradually by the outlet roll 5 (set at the temperature 10 deg.C lower than the softening point of the resin to be impregnated), the draw dancer 6 (set at 30- 50 deg.C) and the draw roller 7 (set at 20-30 deg.C) to obtain the desired prepreg of 20-30mu thickness. |
