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The characteristics of armour paints, historically used to protect ferrous industrial heritage, are explored. Amour paints contain lamellar and highly reflexive pigments of micaceous iron oxide (MIO) and metallic, leafing aluminium, bound in linseed oil and linseed oil–tung oil mixtures, on an inhibitive and soap-forming linseed oil primer (red lead). It is the first study of the binding media used for historical armour paints and investigates the chemical and physical ageing of armour paints using a multianalytical approach. Naturally aged examples are compared to accelerated aged replica armour paint, and to historical paints. The ageing and degradation reactions are assessed by complementary GC–MS and FTIR, together with measurements of wettability, hardness and surface colour. The historical paint formulations include linseed oils and alkyd binders. The results confirm that the leafing effect of aluminium pigments results in only a small concentration of binder at the surface: the paints studied reflect light and form a strong chemical and physical barrier. Linseed oils and tung oil mixtures have been proven to be suitable for the production of armour paints, but the evaluation of ageing and assessment of physical changes will require further investigation.

International audience; This study focuses on the short-term reactivity of zinc oxide with different types of drying oils. Chemical grade zinc oxide (with diameter

Thermogravimetry coupled with differential scanning calorimetry (TG–DSC) has been commonly used in the field of conservation of Cultural Heritage for the study of art objects, especially for the characterisation of inorganic matrixes. In recent years, thermal analyses have been applied to the study of organic painting materials. The advantages of performing TG–DSC are linked to the fact that it is micro-destructive technique which does not require any treatment prior the analysis and provide useful information in relatively short time. The aim of this study is to describe the application of TG–DSC on the study of oil binders used in contemporary paints. Even if synthetic binders have become increasingly popular in the 20th century, many contemporary artists still prefer the more traditional media: drying oils. Although the wish of recalling traditional methods, much practical knowledge in paint preparation by mixing drying oil and pigments and in the behaviour of the mixture has been lost. This is mainly due to the different composition of contemporary materials in comparison with the traditional ones and may sometimes lead to different drying properties of the oil paint formulations and consequent problems in the art creation and conservation. For answer to this artistic need and in particular to the difficulties outlined by artists themselves in producing and employing oil paints, unpigmented and pigmented oil films were studied after a week, 1 and 2 years of natural drying under laboratory conditions. Thermal analyses were performed in air flow: the focus of this research was, in fact, to study the thermal and oxidative behaviours of young films for better understanding the very first processes leading to the formation of the film.