The acids migrate or transfer into the photograph and cause it to become brittle and to change color. The sticky surface of tapes eats into a photograph, hardens and leaves a residue that marks the photo. Do not use albums with adhesive pages for important photos and souvenirs. Avoid inks and markers. Inks contain acids that can eat into a photograph.
Inks can also bleed through photographs and onto adjoining photos.
Make notes on the edge of the photo, use pencil if possible. Most albums use an unstable, acidic plastic which contributes to the deterioration of photos. Acceptable stable plastics are polypropylene or polyethylene. Photo fronts should never directly touch each other. Spacers built into the bindings keep the album from fanning at the outer edge.