The poly lining lowers static electricity as it reduces wear and tear in the handling of the disc, as well as being resistant to solvents, bases, acids and oxidants.
The film has anti-static properties and contains no additives such as softeners or similar products that could react with the vinyl of the records.
Lined sleeves are much smoother on the inside than unlined paper sleeves, a difference you are sure to notice immediately. As non poly-lined sleeves may scratch your records when removing and inserting.
Copes well with high humidity and is stable in most heating conditions.