When books wrinkle due to being wet, there is no guarantee that they will ever be less wrinkled. When inks and dyes bleed and run and when coated paper sticks together, that is irreversible. Freeze-drying will limit and often even eliminate these problems but will not reverse them if they have occurred before the materials are frozen.
When large numbers of books are water-damaged and mass replacement is not a feasible option, the objective becomes returning the books to a usable state. Such was the case with many of the books from the water incident at Kinsey Institute Library which were treated by the General Collections Conservation unit.
After freeze-drying, books are re-humidified under controlled conditions, then placed in a standing press. The actual labor of the flattening process requires relatively little time, but it takes rather a lot of time overall, due to two factors. First, our capacity for doing the work is small, re-humidification chamber space and press space both being quite limited. Second, the books must remain in the presses for 24 hours or more. So, the job takes considerably more time by the calendar than by the clock.
A few examples are shown above in before and after condition. These books were soaked the same as if they had been submerged, so their reaction was pretty extreme. For instance, the first book pictured isn’t fanned open; it wouldn’t close any further. As you can see in the after image, the books are not restored to as-new condition. They still have wrinkles and tide lines. But they are at least book-shaped and functional.