Despite its image as a high-tech country, a lot of Japan’s government paperwork still takes the form of bound collection of hard copies of legal documents. The National Diet Library has the responsibility of housing countless numbers of these collections.
However, like a fiery balrog, water is the bane of physical printed documents (which admittedly have a bit of a problem with fire, too). The National Diet Library occasionally has to deal with restoring books that have become wet before water damage sets in. Recently, the library revealed its simple, easy to copy technique for properly drying out a soggy book.
The library’s website lists spilled cups of water, ruptured pipes, leaky roofs, and malfunctioning sprinklers as probable causes of water damage, confirming our theory that the building does not, in fact, operate as a venue for raging after-hours keggers for Japanese politicians.
▼ A book, damaged by water or perhaps that blue liquid from diaper and tampon commercials

The procedure doesn’t call for any equipment you’re unlikely to have laying around you home or office, nor does it require any special training.
You’ll need:
– Cloth towel, preferably made of absorbent material
– Roll of paper towels or stack of printer paper
– Electric fan or hair dryer
– A few hard flat surfaces (cutting boards will do the trick)
– Paperweight or something similarly small and heavy

Start by pressing the towel onto the wettest parts of the page, to soak up as much of the liquid as initially possible.

Next, place paper towels or printer paper between the pages of the book that are still wet, being carful not to jam so much in as to distort the shape of the book itself.
▼ Although, if the National Diet Library has talking books, as shown here, we really wonder why it matters if the pages are legible or not

If the book’s cover is stiff enough to support its weight, stand the book on edge, with the wet portion at the top. If the cover is too soft for this, lay the book flat on the table. Turn on the fan or dryer and aim it at the book. Make sure the air flow is not so strong as to knock any standing books, and if using a dryer use only cold air, not hot.

As they become damp, periodically replace the paper towels or printer paper inside the book as needed, until the moist portions of its pages no longer feel cold to the touch.

Once that happens, remove the drying papers, and place the book or books on a hard, flat surface to finish drying. Alternate layers of boards and books, with a single sheet of paper above and below each book to prevent sticking. To keep the books from warping, place the paperweight on top of the entire stack.

If complete drying takes more than a day, remove the books from the stack at least once every 24 hours and flip through the pages to make sure they’re not fusing together.

The library’s website goes on to list a few other points of advice. If, as a result of the moisture, mold has started to develop, the book should be isolated from other materials and the affected areas cleaned with an ethanol solution.
Photos tend to be printed on paper with a special coating, which is particularly prone to sticking to other similarly-coated surfaces. Should this occur, the pages can be separated using a spatula, although this also carries a risk of damaging the surfaces, and should be done with caution, if at all.
Finally, the National Diet Library, and we here at RocketNews24, take no responsibility for any problems that may occur with the above process, and stress that it is not to be used with materials that are delicate or have already reached an advanced stage of degradation.
In other words, this technique isn’t so much for your copy of the magna carta stained with fine port on as it is the 100 yen comic you spilled some canned beer on.
Sources: National Diet Library, Net Lab
Insert images: National Diet Library

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