Introduction to Different Paper
The watermark is a sign of quality. It assures the user that the paper is a fine paper. The watermark generally will identify the manufacturer, the brand name and the amount of cotton fiber, if any, in the sheet. Through the use of a special roller called a "dandy roll", the watermark is impressed inside the paper early in the manufacturing process. A watermark is visible when the paper is held to the light. Many world currencies are watermarked with portraits of famous people.
In addition to its importance as a sign of quality, the watermark also helps the user identify the correct side and position of the paper on which to print. The proper side on which to print is the one from where the watermark can be read correctly while looking through the paper.
Cotton is a natural fiber and is one of the strongest and most durable fibers known to man. Papers manufactured of cotton fiber will last longer and hold up better under repeated handling and variant environmental conditions than paper made from wood pulp.
Acid Free Formulation:
Paper which has no acid or residual acid-producing chemicals is called "acid free". Papers that are "acid free" will resist yellowing and disintegration longer than sheets that are not acid free. This is particularly true as the percent of wood pulp in paper relative to the amount of cotton increases.
The term "bond" has no actual meaning in the manufacturing process. The term comes from WW I when war bonds were printed on cotton fiber papers that were extensively watermarked. The extensive watermark was used to protect buyers from bonds sold by counterfeiters (the first saafety paper).