Highly transparent, low haze and ultraviolet to blue light blocking cellulose films tailored by lutein as electronic screen protectors

Anti-blue light films with high transparency and low haze that completely originate from renewable and biodegradable biomass materials for eye protection is a growing trend with great demand in the near future. Therefore, in this study, a natural bioactive ingredient, lutein, was incorporated into the cellulose matrix via a green and facile adsorption strategy to prepare biodegradable ultraviolet (UV) and blue light filters. The lutein/carboxymethylated cellulose films (L-CCFs) displayed high anti-UV capacity, with UV-A and UV-B blocking ratios of 52.7 %-90.9 % and 44.1–85.2 %, respectively. The composite films could block 83.1–97.8 % of blue light in the 400−500 nm region while maintaining high transparency (86.6–89.3 %) and low haze (2.1–2.6 %). By light absorption, the films can effectively shield blue light emitted by light-emitting diodes, sunshine, lighting systems, mobile phone, and computer screens. Quite encouragingly, the addition of lutein significantly increased the water contact angle from 40.1 to 70.5° and the composite films have excellent liquid barrier properties. Meanwhile, these films exhibit higher light stability than lutein powders, thus greatly extending the service life of the film as a blue light shielding material. Moreover, the films have excellent mechanical strength (>110 MPa) and biodegradability. These films prepared entirely from natural resources offer great application value in the fields of electronic screen films and spectacle lenses.