Polymide Films PWB

"Polymide Films absorb a great deal of moisture. Polymide laminates must be baked at more than 1 hour at 100'C or better for a double sided PWB prior to exposing the laminate to elevated temperatures such as that required for soldering. Moisture absorption is very rapid and the laminate should be stored under dry conditions if not ready for immediate production." - High Performance Printed Circuit Boards By: Charles Harper

Boards must be stored in a controlled environment, ANSI-J-STD-001: 18-30*C, 30-70% RH.

How rapid is the moisture absorption of this board? My PCB supplier gave me the Moisture Absorption Value which is 0.35 wt.%. And I'm not sure if it makes sense as I'm not good at this.

Can anyone help me and provide me good baking time & temp. I patterned our baking with my old experience which is 80'C -- 16 hours. Is is enough or too much? what is the bakeout time of Polymide Film PWB's?

Thanks and best regards,

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