Ed #8 Digital Variables

Having the right paper is important too. Papers used with digital printing should be engineered to work well with toners and stand up to the heat that can be generated during the image fusion process. A strong surface helps to protect against the picking sometimes caused by tackier, waterless inks. A smooth surface helps to hold the toner evenly.

It’s especially important to control the moisture content of the paper, before and during printing. A digital paper typically contains less moisture than conventional offset papers, so there’s less moisture to evaporate through the printed image when the toners are fused by heat. And both temperature and moisture content are critical for the paper to receive the correct electrostatic charge during digital printing.

The paper should be acclimatized in the press room for at least 24 hours prior to printing, and the humidity should be low. In addition to affecting print quality by causing the toner to cake, high humidity can also cause the paper to jam the press. If a ream of paper is opened and not used immediately, it should be re-wrapped to keep it from absorbing moisture. And while some types of equipment can handle it, in general it’s best to avoid papers with heavy textures, since the toner may not adhere evenly or might rub off on the high spots. Always make sure that the paper’s basis weight matches the specifications of the equipment that will be used to print the project.