The current owner of an item is only its temporary caretaker, with the obligation to see that it leaves their possession in the same condition as when it arrived. In other words, it's our responsibility to protect our newspapers, documents, postcards, comic books, stock certificates, etc. If that sounds overwhelming, rest assured that it's not as hard as you might think, using a few simple and easily remembered techniques. This means the paper itself, without any regard to its surroundings.
Rag paper is very easy.
The paper was manufactured using materials that should last for centuries. In most cases rag paper needs nothing done to it. Acid was used in the manufacture of woodpulp paper and no matter how much the paper was washed after it was made, or whether the paper is a year old or a century old, some of that acid is still in there breaking down the fibers of that paper. We see this as the browning, brittleness and chipping that affects newsprint. For long-term preservation of newspapers printed on woodpulp paper it is necessary to deacidify them.