Bond paper belongs to the class of paper called ‘writing’ paper. It is made of cotton rag pulp which gives it strength. It is also sized for opacity and toughness and the metallic sound. Bond paper is different in its non- absorbent qualities as it is well sized so as not to absorb water-based writing ink. It is also tough and strong due to rag content in the pulp.
The sizing may be animal or gelatin or tub sized as distinct from engine sizing used for printing paper. The word ‘bond’ owes its origin due to the fact that originally IOU’s or promissory notes (bonds) were widely using this rag content durable paper.
Smooth printing paper is used for photocopying to attract the toner powder. In the U.S, hardwood sulphite is beaten well and hydrated to produce bond paper. It produces crackle (sound) and results in a high mullen (tensile strength) bond paper which is water marked as ‘sunlit’, JK and ‘Executive’. They are used in making paper for insurance policies, stock certificates, bank notes and other important documents for longevity. There are machine dried and air dried bond papers.