Scalable Water-Based Organosilane–Lubricant Coatings for Pharmaceutical Glass Packaging with Enhanced Scratch Resistance and Reduced Friction

This study explores the development of low-friction, water-based coatings tailored for industrial applications in pharmaceutical glass packaging. The study focuses on scalable deposition strategies to obtain durable low-friction coatings suitable for industrial implementation. To balance mechanical performance and application efficiency, two different application approaches based on a two-component coating (aminosilane primer and lubricant) were investigated. In the first case, the coating is deposited in two steps, while in the second, a single deposition step is used. Characterization through contact-angle measurements and X-ray photoelectron spectroscopy confirmed successful deposition of the primer on the glass surface. Scratch resistance tests revealed an increase in the critical load for fracture initiation from 4.5 N for uncoated glass to 6.5 N for the best-performing coating, indicating improved resistance to surface damage. Friction performance was assessed via tribological tests, which demonstrated that the primer–lubricant coatings achieved the lowest coefficient of friction (approximately 0.2), compared with uncoated glass (stabilizing at approximately 0.3 after an initial value of 0.5) and lubricant-only coatings (approximately 0.4–0.5), confirming the beneficial role of the primer in the coating system. Representative profilometry measurements indicated sub-micrometric coating thicknesses, while UV–Vis measurements confirmed that the coatings preserved the high optical transparency of the glass substrate, with average visible transmittance values above 90%. Furthermore, the successful implementation of the coating using an automated spray system demonstrates its potential for scalable industrial production. These findings support the potential of environmentally sustainable water-based coatings for pharmaceutical glass packaging by combining improved mechanical performance with preserved optical transparency and compatibility with scalable spray deposition.