Today's new word is LIGNIN

Yes, another one I should have remembered, but didn't. Lignin is an organic bonding material found in the wood fiber of untreated papers. The acidic properties of lignin have a deteriorative effect on paper and photographs. When buying a scrapbook or photo album makes sure they are lignin free.

At How Stuff Works: "Lignin makes wood stiff and trees stand upright. You could say it acts as a glue to bind the cellulose fibers together. It is a polymer, a substance that is formed by the joining of simpler molecules into giant molecules that act differently than the smaller molecules did. Dr. Hou-Min Chang, a professor of wood and paper science at N.C. State University in Raleigh, N.C., compares lignin to the concrete used in buildings, with cellulose as the steel frame. Without lignin, Chang says, a tree could only grow to be about 6 feet tall. Lignin also helps protect the wood from pests and other damage. Newsprint, which must be produced as economically as possible, has more lignin in it than finer papers. At the mill, the wood that will be turned into newsprint is ground up, lignin and all." That's why old newspapers turn yellow very quickly.

About 30 years ago I moved these photos of my 12 year old classmates from a scrapbook that was crumbling to a cheap photo album, and now it's starting to go. Fortunately, black and white photos are a lot more permanent than color.

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