Thomas P. Flanagan was a research chemist with National Starch and Chemical Company in Bridgewater, NJ. He is the holder of 20 US and 40 international patents for glues and adhesives designed between 1965-1990. Flanagan is the author of Hot-Melt Adhesives, a chapter in The Handbook of Adhesive Bonding (Macmillan, 1973) and was recognized for his scientific achievement at the 1988 meeting of the Technical Association of the Pulp and Paper Industry (TAPPI). I interviewed him by phone at his home in Venice, Florida in April 2010.
EB: Tell me a bit about how hot melt adhesive changed book publishing.
TF: Hot melt glue replaced water based glues and allowed book and magazine printers to increase production–by 100 to 200 percent–and cut costs at the same time.
EB: How so?
TF: The hot melt glue solidifies right away, so publishers could make more books faster. With water-based glues you had to wait for the glue to dry. It also allowed what’s called perfect binding—where the signatures are guillotined and glued rather than sewn. Sewing signatures was very time consuming. Before long hot melt glue was used for paperbacks, hardbacks, and magazines—not all, but lots of them.
EB: When did printers start using hot melt adhesive?
TF: It started in about 1955 or so, with the Readers Digest. That had been a stapled magazine but by using glue, the publisher could print is faster and cut back on the size of the magazine to save on paper costs. TV Guide was a big early adopter and they had about seven processing plants around the country for different television markets. Playboy was also a customer and when they sent copies of their magazine for glue testing I kept them in the cabinet so no one would be offended. But one day they all disappeared from the lab.
EB: Were lots of companies making hot melt adhesive?
TF: National Starch was the leader. But others followed. Manufacturers were interested in having more than one supplier.
EB: Were there any big problems in the switch from water-based glue to hot melt?
TF: One big complication was that some bookbinders stopped drying the ink during the printing process. They put the books right into the binding machine. But the problem was that after about three month the ink solvent bled into the glue and ruined the backbone of the book. The bindings would crack and fall apart.
Some publishers were suing us for defective glue, so I researched the problem and ran some test runs. The test proved that the run of books with the ink fully dried were fine and the run of books with the ink still wet cracked. So the lawsuit was dropped.
EB: How was the hot melt glue applied to a binding?
TF: The glue was in a heated tray and applied by rollers that went over the cut edges of the pages. Usually the first rolling would set the places in places and a second rolling would reinforce the binding and apply glue to hold the cover.
EB: I’ve got a paperback book here that has a little hinge on the cover. What’s that for?
TF: The hinge is a matter of supporting the cover–hard cover books typically have a gutter and hinge. On paperbacks often the cover would be folded over and hinged to let the glue attach the first and last pages as well.
EB: What the difference between a perfect binding and a burst binding?
TF: With a perfect binding the pages are cut and glues. With a burst binding the signatures were scored so that glue could penetrate the individual signatures. Burst binding came later as a means to preserve as much of the look of traditional hardbound books as possible. And it made for a much nicer book. Some bookbinders also used headbands to make glued books look better.
EB: I see that you have almost two dozen patents. How did the patent process work?
TF: I have 20 US patents, patents for everything from paperback glue to disposable diapers.
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