Water-based poly(2-ethylhexyl acrylate-itaconic acid) removable adhesives with frost resistance for digital inkjet printing

Adhesives are nonmetallic materials used to bond each layer in many applications for its flexibility. For digital inkjet printing, the requirements of adhesives performance are demanding as they must be able to adhere well to adherend, be removable without leaving adhesive residue, or even causing any damage. Water-based polyacrylates have been widely used for backing adhesive layer in application of digital inkjet printing, due to their various advantages. While the application has been limited on account of the weak frost resistance of common polyacrylates, which could not be used directly under low temperature storage. To improve the weak frost resistance, water-based poly(2-ethylhexyl acrylate-itaconic acid) was synthesized. Itaconic acid (ITA) could be greatly beneficial to improve the frost resistance. The polyacrylates could still be used directly, even after being frozen below at −18°C for 16 hr. The adhesion properties of polyacrylates could also be enhanced by moderate ITA. The results show that the optimal amount of ITA was 2 mass%. The overall properties of the resulting polyacrylates with the 180° peel strength of 2.73 N/25 mm, the tack of 23 #, and the shear holding power of more than 24 hr are suitable for practical applications on removable adhesives for digital inkjet printing.