How to Teach the Use of Gels and Thickeners in Paper Conservation

This article presents a teaching concept for the application of gels and thickeners in paper conservation, implemented at the Technical University of Applied Sciences Cologne within a four-day course module. The course targets primarily bachelor’s level students, aiming to convey theoretical foundations alongside hands-on experience with various gels and thickeners. During the course, students prepare eight different materials—including cellulose ethers, gellan gum, laponite®, agarose, xanthan®, and advanced commercial products such as Nanorestore Gel® Peggy—and test them on water-sensitive substrates. Three kinds of coloured stamp ink and a copy pencil serve as a water sensitive media. Key parameters such as water absorption, moisture release, and residue formation are examined and documented. All recipes are given to prepare the gels and thickeners. The curriculum combines theoretical lectures, video tutorials in a flipped classroom format, and practical lab work, fostering active learning and technical confidence. Student evaluations include written and visual documentation of their observations as well as oral feedback. Results align with established literature, confirming distinct material behaviors and providing a comprehensive overview for students. The course also promotes technical, methodological, and social skills through collaborative group work and guided practice. By integrating blended learning elements that maximis e both contact time and independent study, the program offers an effective and modern educational approach. This teaching model contributes significantly to the professional training of future paper conservators by equipping them with essential knowledge and skills for the practical application of gels and thickeners in conservation interventions.