Sustainable <scp>3D</scp> Printing of Antifouling and Antibacterial Pet Products With Zwitterion/Lignin–Modified Composite Resins

ABSTRACT The growing population of “pet parents” has fueled the rapid expansion of the global pet product industry, while surface biofouling poses significant risks to both animal and human health. In this study, we developed a novel series of photocurable composite resins incorporating gradient concentrations of sulfobetaine methacrylate (SBMA) and partially methacrylated lignin (PML) through vat photopolymerization 3D printing technology. The zwitterionic SBMA component endowed the resin surface with enhanced hydrophilicity owing to its robust hydration capacity, effectively preventing protein adsorption and bacterial attachment, thereby achieving superior antifouling performance. The antibacterial efficacy progressively improved with increasing PML content, with the optimal 20% PML formulation achieving outstanding inhibition rates of 97.3% ± 2.6% and 96.8% ± 2.4% against S. aureus and E. coli , respectively. Furthermore, all composite resins exhibited excellent biocompatibility, sustaining cell viability above 90% for 7 days. We used this approach to design and prototype various pet products with the zwitterion/lignin–modified composite resins, which demonstrated simultaneous and durable resistance to both protein adhesion and bacterial colonization while maintaining exceptional biocompatibility. These findings strongly validate the practicality and effectiveness of our dual‐functional resin strategy for next‐generation pet product applications, offering promising solutions to address current challenges in combating biofouling.