I found the old Kodak paper envelopes deteriorate with use and start shedding white flakes. If I want to continue using the envelopes for loading exposed film, I put black photo tape over the torn paper edges.
Newer films seem to have better, plastic envelopes. I wish someone sold plastic envelopes as well as new, empty 4x5, 5x7 and 8x10 film boxes.
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