First Insights into the Formation of Metal Soaps in Alkyd-Based Paints: A Proof-of-Concept Investigation Using FTIR...

Area of Science:

• Art Conservation Science
• Materials Science
• Chemistry

Background:

• Metal soap formation is a known phenomenon in oil paintings.
• Alkyd paints, prevalent in modern and contemporary art, possess unique chemical properties compared to traditional drying oils.
• Understanding alkyd paint degradation is crucial for artwork preservation.

Purpose of the Study:

• To investigate the formation of metal soaps specifically within alkyd-based paint media.
• To compare metal soap formation in mock-up alkyd paints versus real-world contemporary artworks.
• To provide insights for the conservation of modern and contemporary art.

Main Methods:

• Preparation of mock-up alkyd paints using an alkyd binder, potassium hydroxide, and pigments (smalt, zinc white, lead white).
• Analysis of mock-up samples under ambient conditions and after artificial aging.
• Investigation of paint samples from two contemporary artworks by Italian artists.

Main Results:

• Confirmation of metal soap (metal carboxylate) formation in alkyd paint systems.
• Observed differences in metal soap formation kinetics compared to drying oils due to alkyd binder properties.
• Consistent findings of metal soap presence in both experimentally prepared and artist-created paint samples.

Conclusions:

• Metal soap formation occurs in alkyd-based paints, impacting their long-term stability.
• The study validates the occurrence of these degradation processes in actual artworks.
• Findings have significant implications for developing targeted conservation strategies for modern and contemporary art.