The Abbey pH Pen tests the pH of paper, mat board, folders and envelopes. Simply mark an inconspicuous spot on the material and check the color as soon as the indicator fluid dries. Purple indicates a pH of 7.0 or above, yellow indicates a pH below 6.5. Paper often requires an alkaline reserve and a pH of 7.0 or higher in order to last a hundred years or more.
YourStory™ Collection: This product has been handpicked to help with your personal preservation projects. What's Your Story? >