A printing defect characterized by the printing of ink that is to all appearances dry, but which rubs off easily. Rub-off is commonly caused by an inadequate binder formation, or an inadequate quantity of binder present in the ink, both of which impede the adhesion of the pigment particles to the substrate. It can also be caused by excessive or premature absorption of the ink vehicle into the substrate. Rub-off can be compensated for by mixing a varnish, a heavier resin, or wax with the ink prior to printing. If rub-off is a problem after printing, an overprint varnish may alleviate the problem. Also known as scuffing.
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