Thank you Chris, Dominik and George.

If I understand correctly there is a protector layer for panchromatic emulsion and under these two layers there is another protector layer for starch grains. If we dip everything to alcohol , there is a risk to damage the starch layer when removing top three layers. I wish top protector layer and bottom protector layer have different formulas.
May be top protector layer could be removed with matchsticks and cotton balls slowly with least alcohol inside.

May be top layer could also removed slowly with 2000 or more grade sanding paper