I got a box of 100 sheets of 8x10 fiber based black and white paper. The box showed no signs of bad handling. All prints made using this paper consistently show a very thin black band on one of the eight inch sides. The density of the band is uniform along its length. Prints made using different developers show the band. I developed and processed an unexposed sheet straight from the box. It shows the band. This to me rules out any kind of light leak in the darkroom being the cause of the density on the prints. I removed a sheet from the box and exposed the sheet to household light for hours. That sheet DOES NOT show the band. Sheets from both the top and bottom of the stack of paper show the band. That makes it likely all the sheets are similarly affected. Somehow the sheets have received exposure. But how? Is this paper defective?

