The paper is acid free to help prevent yellowing and ensure that documents still look good after long term storage. At staples you can sometimes get a ream of copy paper for 1 cent.

Costco Copy Paper Letter 20lb 92 Bright 10 Reams Of 500 Sheets
White copy paper pallet letter size 8 12 x 11 20 lb ream of 500 sheets 10 reams per carton pallet of 40 cartons 172999 pallet reg 115960 sale save 570.