Treating PMMA: Filling Scratches and Chips Workshop

Since its introduction in the 20th century, poly (methyl methacrylate), or PMMA, has become increasingly popular with artists and designers for its versatility, transparency, and ability to be shaped and colored. Clear PMMA has been extensively used as an artistic medium to make sculptures and objects and, since the 1980s, to face-mount photographs. As PMMA is prone to surface damage, such as scratches and chips, this workshop focused on its treatment.

This mini online workshop offered in 2021 combined theory and practice. The theory portion highlighted the challenges that the conservation of PMMA poses and included discussion of the approach used to investigate the suitability of materials and methods for the development of successful and safe surface treatments for this plastic. Practice was dedicated to the preparation of resins and their use in the repair of scratches and chips on PMMA.

A presentation was followed by practical sessions including demonstrations, hands-on exercises, and group discussions. A kit with PMMA samples, a face-mounted photograph, brushes, steel pins, glass rods, mixing cups, and spectacle cloths was sent to each participant to support the hands-on exercises.

Additionally, each participant gained access to a course website, which included instructions for mixing resins and supporting literature, as well as videos demonstrating the treatment of scratches and chips.

The workshop aimed to provide conservators with the theoretical and practical tools to restore PMMA surfaces, including:

• a brief introduction to PMMA and the research study on developing filling treatments
• fill materials and their preparation, properties, advantages, and disadvantages
• gaining familiarity with various materials, tools, and application methods
• understanding the behavior of the selected resins during application
• assessing the quality of the repairs

Anna Laganà, Senior Research Specialist, Getty Conservation Institute