Best Printing is at Comfortable Conditions
Of course now I know all about the issues of humidity and moisture content. The moisture content of a print shop is measured as relative humidity and it affects the amount of moisture in paper. Typical paper is produced to an absolute moisture content between 4.0 and 6.0%, meaning 4 to 6% of the paper’s total weight is made up of water. But once unpacked the paper can either absorb or dissipate moisture. In the best conditions the paper is designed to be stable in a 45-55% relative humidity (RH) at 72°F environment.
The key is making sure you purchase and use the right paper for the right use and maintain stable conditions which are close to those recommended. Different printing processes work best with certain amounts of moisture. In digital printing the moisture content can affect the toner adhesion, paper jams and the fuser roller temperature. In offset it can affect the interaction between the ink and the press, the paper and the press, and the ink and paper. Inkjet is affected by many of the same issues but is even more susceptible to dot gain or ink spreading, drying delays and ink show through.