PURPOSE: To continuously obtain a uniform foam body at high yield by covering polyimide precursor with covering cloth which is substantially steam- impermeable and microwave-compatible, and radiating microwave radiation.
CONSTITUTION: A polyimide precursor body, and a foam structure body generated from this are covered with covering cloth which is substantially steam- impermeable and microwave-compatible, and exposing microwave radiation to upper parts of a top part, side surfaces, and end parts of the polyimide precursor body and the foam structure body generated from this in such a way that an upwardly invading degree of the radiation to a bottom part of the precursor body and the foam structure body is reduced. A temperature of at least a lower part of the polyimide precursor body is risen to a proper temperature in a range of 50-200°C in exposure.
HENRII YUUJIN BUREMERUJIIKU
REIMONDO RII
| JPH0241333A | 1990-02-09 | |||
| JPH0238433A | 1990-02-07 |