In the past week two students, using recenly purchased boxes of Multigrade IV, have had the emulsion start to separate from the paper base after a printing session. The lifting is along the long side of 8x10 sheets and are about 6mm diameter semi cricles. Has anyone else noticed this? In years of teaching this is the first time I've see it.
A couple of questions for you: Is this RC or fiber? How long was the paper wet in total? What is the batch number of the bottom of the box? Lastly, have you contacted Ilford about the problem? They are typicaly very responsive to problems like this, but they will almost certainly want to know the information printed on the bottom of the box.
Please let me know the batch number, and also the pack size 10 sheet, 25 sheet , 100 sheet box :
2.5 hours wet should not be an issue, delamination is incredibly rare, normally caused by damage in the dish ( tong scratch ) but obviously I will check it out.