In an article published on June 2, 2017 by news provider Packaging News, author Waqas Qureshi reported on a new study by testing company Intertek that investigated the recyclability of standard paper cups. According to the study report, all types paper cups (e.g. compostable, biodegradable, coated) made on existing cup machines “have an internal exposed paper seam.” Therefore, the paper needs to be waterproof in order for the cup not to disintegrate when filled with (hot) liquid. Such paper is called ‘cup stock.’ The study showed that “cup stock is so waterproof that it won’t breakdown within the standard re-pulping times of a commercial mill,” Qureshi informed. The cup stock’s water resistance thus “prevents recycling in any normal recycling process,” stated Intertek. In addition to the cup stock’s waterproof properties, the commonly used inner plastic coating in paper cups is another barrier to recycling.
Waqas Qureshi (June 2, 2017). “Waterproofing chemicals ‘hindering paper cup recycling.’” Packaging News