Method for removing ink or other foreign materials from the surface of an article

A method for removing ink and/or a foreign material different from ink from the surface of an article, wherein at least a part of the surface of the article comprises a polymer selected from the group consisting of polyolefins, polystyrene, melamine polymers, polyvinyl chloride, polyethylene terephthalate, polyamides and mixtures thereof, the method comprises the following steps:

• i) providing an ink imprinted article and/or an article having a surface covered at least partly by a foreign material different from ink;
• ii) contacting the article provided in step i) with an acid having a pKa in the range from −10 to 7 having a minimum concentration of 1 wt.-% for solving the ink and/or the foreign material different from ink or their degradation products in the acid;
• iii) separating the acid and the therein dissolved ink- and/or foreign material different from ink or their degradation products from the article to obtain a deinked article and/or an article with a surface free from foreign material.