Materials and Methods for Surface Cleaning and Removal of Film-Forming Materials

Level 1 Base

Instructor: Paolo Cremonesi, an independent Conservation Scientist, Chemist and Biochemist, trained also in the conservation of paintings, active in research, development and training in several European countries.

Registration Fee

Course topic

The webinar consists of three sessions of 6-7 hours each, alternating between discussion of theoretical principles and demonstration of practical applications. It focuses mainly on the following types of artefacts: polychrome works such as paintings on movable supports and wooden sculptures, and paper limited to works of the “oil on paper” type. The specific characteristics of mineral/inorganic supports would require a separate discussion.

The level is deliberately ‘basic’, so no specific requirements are needed other than a basic knowledge of chemistry, materials and restoration operations. However, participation is limited to restorers, restoration assistants and students in conservation and restoration faculties and training centres. Other professionals are excluded.

Participants will be provided with notes in advance.

⇒Day 1 – Friday January 9, 2026

All times are expressed in Italian local time (Rome, GMT+1/GMT+2 depending on the season).

9:00 AM – 1:00 PM. Theory. The physical and chemical properties of water. From pure water to the aqueous environment. pH, Acids and Bases, buffers. Ion concentration and the tonicity of aqueous solutions. Adapting the medium conditions towards surface cleaning or removal of film-formers. Classification and properties of gelling materials. Aqueous rinsing procedures.

2:00 PM – 6:00 PM. Practical Applications. Preliminary visible, UV and microscope examination of the surface. Contact Angle. Dry Cleaning. Measuring surface pH and conductivity. Preparing and testing aqueous buffered solutions in free and gelled form.

⇒Day 2 – Friday February 6, 2026

9:00 AM – 1:00 PM. Theory. Classification and mode of action of complexants and chelators. Usefulness and limitation. Interactions. Classification and mode of action of surfactants. Usefulness and limitation. Interactions. Strategies for safer delivery of water to sensitive surfaces.

2:00 PM – 6:00 PM. Practical Applications. Preparing and testing aqueous buffered solutions containing surfactants and chelators, in free, gelled and rigid form, for surface cleaning and removal of film-formers. Application to water-sensitive surfaces.

⇒Day 3 – Friday March 6, 2026

9:00 AM – 1:00 PM. Theory. Organic Solvents. Classification, properties and mode of action of neutral and dipolar solvents. A safer approach to the use of solvents. The parametrization of organic solvents: usefulness and limitation. A gradual approach to the solubility of film-formers through solubility tests. Gelling organic solvents. Wolbers’ solvent-surfactant gels.

2:00 PM – 6:00 PM. Practical Applications. Conducting the solubility test for removal of organic film-formers. Preparing and testing solvents in gelled form and as Solvent-Surfactant Gels.