The aging and fragility of books lies not in the length of storage time, but in how to deal with the acidic substances contained in the pages. Paper documents have substances suitable for insect reproduction and growth because of the carrier itself. Books are easily stained by oil stains, ink, etc. Books are not mildew-proof, they become brittle after aging, they will turn black due to falling dust for a long time, and they are not easy to erase.
In ancient times, the ancients often needed to print books, and moths were a powerful killer of books. Ancient protection books are generally smoked with sandalwood, and the smoke produced by burning sandalwood can repel insects and prevent insects from eating. Bookcases are generally made of sandalwood or camphor wood.