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Zinc Soaps: An Overview of Zinc Oxide Reactivity and Consequences of Soap Formation in Oil-Based Paintings

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Metal Soaps in Art

Part of the book series: Cultural Heritage Science ((CUHESC))

Abstract

Zinc white – zinc oxide – is a prevalent industrial age pigment which readily reacts with fatty acids in oil-based paints to form zinc carboxylates (zinc soaps). Pigment properties, oil composition, paint additives and environmental conditions are all significant factors in this process. Release of fatty acids via hydrolysis is particularly implicated. Formation and crystallization of zinc soaps in paintings has serious visual and structural consequences. Fourier transform infrared spectroscopy (FTIR) is a highly sensitive technique for detection of metal carboxylates. Progression of soap formation and distributions are distinguishable in paint cross sections through correlation of microscopic images, elemental analysis and FTIR mapping. Aluminum stearate was found to strongly influence zinc stearate formation during investigations of naturally aged oil-based artists’ commercial and custom-produced reference paints containing zinc oxide in various oil and pigment combinations. Zinc soaps are implicated in deterioration of increasing numbers of paintings dating from the nineteenth century onward. They may manifest as disfiguring lumps or surface blooms resistant to removal. In other paintings, paint cleavage is associated with high concentrations of crystalline zinc soaps at unstable interfaces. The condition of paintings affected by zinc soaps is challenging conventional approaches to cleaning and consolidation and requires continuing research.

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Notes

  1. 1.

    Zinc concentrate is an intermediate product obtained from ore and used as raw material in the production of zinc metal and potentially, in turn, for French Process zinc oxide.

  2. 2.

    Reference spectra are shown in transmittance format where the logarithmic intensity scale assists visual representation of weak CH2 progression bands.

  3. 3.

    Aluminum stearate has its major carboxylate absorption at 1588 cm−1.

  4. 4.

    There is no corresponding indication of lead stearate formation (characterized by carboxylate peaks at 1513 and 1419 cm−1) in grounds with lead.

  5. 5.

    The small peak at 3027 cm−1 reflects aromatic bonding present in the embedding medium rather than unsaturation in the carboxylate chain. While undesirable, the minor penetration of embedding medium evident in spectra from the periphery of the sample does not interfere with the v as COO− absorption bands for zinc stearate.

  6. 6.

    Brucite group minerals have formula M2+ (OH)2 with hexagonal crystal system and a layered lattice structure (www.mindat.org/min-29278 accessed 15 March 2017).

References

  • Bertrand L, Refregiers M, Berrie B, Echard J-P, Thoury M (2013) A multiscalar photoluminescence approach to discriminate among semiconducting historical zinc white pigments. Analyst 138:4463–4469. https://doi.org/10.1039/c3an36874b

  • Bomford D, Kirby J, Leighton J, Roy A (1990) Art in the making: impressionism. National Gallery Publications Limited, London

    Google Scholar 

  • Boon JJ, Hoogland FG (2014) Investigating fluidizing dripping pink commercial paint on van Hemert’s Seven-series works from 1990–1995. In: Van den Berg KJ, Burnstock A, de Tagle A, de Keijzer M, Heydenreich G, Krueger J, Learner T (eds) Issues in contemporary oil paints. Springer, Cham, pp 227–246

    Google Scholar 

  • Bordignon F, Postorino P, Dore P, Tabasso ML (2008) The formation of metal oxalates in the painted layers of a medieval polychrome on stone, as revealed by micro-Raman spectroscopy. Stud Conserv 53(3):158–169

    Article  CAS  Google Scholar 

  • Bronken IAT, Boon JJ (2014) Hard dry paint, softening tacky paint, and exuding drips on Composition (1952) by Jean-Paul Riopelle. In: Van den Berg KJ, Burnstock A, de Tagle A, de Keijzer M, Heydenreich G, Krueger J, Learner T (eds) Issues in contemporary oil paints. Springer, Cham, pp 247–262

    Google Scholar 

  • Brown HE (1957) Zinc oxide rediscovered. New Jersey Zinc Company, New York

    Google Scholar 

  • Clementi C, Rosi F, Romani A, Vivani R, Brunetti B, Miliani C (2012) Photoluminescence properties of zinc oxide in paints: a study of the effect of self-absorption and passivation. Appl Spectrosc 66(10):1233–1241

    Article  CAS  Google Scholar 

  • Cocks EJ, Walters B (1968) A history of the zinc smelting industry in Britain. George G. Harrap & Co. Ltd, London

    Google Scholar 

  • Dredge P, Schilling MR, Gautier G, Mazurek J, Learner T, Wuhrer R (2013) Lifting the lids off Ripolin: a collection of paint from Sidney Nolan’s studio. J Am Inst Conserv 52(4):213–226

    Article  Google Scholar 

  • Ebert B, MacMillan Armstrong S, Singer B, Grimaldi N (2011) Analysis and conservation treatment of Vietnamese paintings. In: Bridgland J, Antomarchi C (eds) Preprints of the ICOM committee for conservation 16th triennial meeting. ICOM-CC, Lisbon, p 1305

    Google Scholar 

  • Erhardt D, Tumosa CS, Mecklenburg MF (2005) Long-term chemical and physical processes in oil paint films. Stud Conserv 50(2):143–150

    Article  Google Scholar 

  • Gardner HA (1917) Paint researches and their practical application. Press of Judd and Detweiler, Inc, Washington, DC

    Google Scholar 

  • Gautier G, Bezur A, Muir K, Casadio F, Fiedler I (2009) Chemical fingerprinting of ready-mixed house paints of relevance to artistic production in the first half of the twentieth century. Part I: inorganic and organic pigments. Appl Spectrosc 63(6):597–603

    Article  CAS  Google Scholar 

  • Hansen CM, Klauss HC (1971) Mechanism of paint seeding. Ind Eng Chem Prod Res Dev 10(2):189–192

    Article  CAS  Google Scholar 

  • Helwig K, Poulin J, Corbeil M-C, Moffatt E, Duguay D (2014) Conservation issues in several 20th-century Canadian oil paintings: the role of zinc carboxylate reaction products. In: Van den Berg KJ, Burnstock A, de Tagle A, de Keijzer M, Heydenreich G, Krueger J, Learner T (eds) Issues in contemporary oil paints. Springer, Cham, pp 167–184

    Google Scholar 

  • Hermans JJ, Keune K, Van Loon A, Corkery RW, Iedema PD (2014) The molecular structure of three types of long-chain zinc(II) alkanoates for the study of oil paint degradation. Poyhedron 81:335–340

    Article  CAS  Google Scholar 

  • Hermans JJ, Keune K, Van Loon A, Iedema PD (2015) An infrared spectroscopic study of the nature of zinc carboxylates in oil paintings. J Anal At Spectrom 30:1600–1608

    Article  CAS  Google Scholar 

  • Hermans JJ, Keune K, Van Loon A, Corkery RW, Iedema PD (2016) Ionomer-like structure in mature oil paint binding media. RSC Adv 6:93363–93369

    Article  CAS  Google Scholar 

  • Higgitt C, Spring M, Saunders D (2003) Pigment-medium interactions in oil paint films containing red lead or lead-tin yellow. Natl Gallery Tech Bull 24:75–95

    Google Scholar 

  • Hofmeister W, Platen HV (1992) Crystal chemistry and atomic order in Brucite-related double-layer structures. Crystallogr Rev 3(1):3–26

    Article  Google Scholar 

  • Keune K (2005) Binding medium, pigments and metal soaps characterised and localised in paint cross-sections. Ph.D. thesis, University of Amsterdam, Amsterdam

    Google Scholar 

  • Keune K, Boon JJ (2007) Analytical imaging studies of cross-sections of paintings affected by lead soap aggregate formation. Stud Conserv 52(3):161–176

    Article  CAS  Google Scholar 

  • Keune K, Hoogland F, Boon JJ, Peggie D, Higgitt C (2009) Evaluation of the added value of SIMS: a mass spectrometric and spectroscopic study of an unusual Naples yellow oil paint reconstruction. Int J Mass Spectrom 284(1–3):22–34

    Article  CAS  Google Scholar 

  • Kühn H (1986) Zinc white. In: Feller RL (ed) Artists’ pigments, vol 1. Cambridge University Press, Cambridge/New York, pp 169–186

    Google Scholar 

  • Maines CA, Rogala D, Lake S, Mecklenburg MF (2011) Deterioration in abstract expressionist paintings: analysis of zinc oxide paint layers in works from the collection of the Hirshhorn Museum and Sculpture Garden, Smithsonian Institution. Mater Res Soc Proc 1319:275–284

    Article  Google Scholar 

  • Mills JS, White R (1987) The organic chemistry of museum objects. Butterworths, London

    Google Scholar 

  • Monico L, Rosi F, Miliani C, Daveri A, Brunetti BG (2013) Non-invasive identification of metal-oxalate complexes on polychrome artwork surfaces by reflection mid-infrared spectroscopy. Spectrochim Acta A Mol Biomol Spectrosc 116:270–280

    Article  CAS  Google Scholar 

  • Morley-Smith CT (1950) The development of anti-chalking French process zinc oxides. J Oil Colour Chem Assoc 33:484–501

    CAS  Google Scholar 

  • Morley-Smith CT (1958) Zinc oxide – a reactive pigment. J Oil Colour Chem Assoc 41:85–97

    CAS  Google Scholar 

  • O’Donoghue E, Johnson AM, Mazurek J, Preusser FD, Schilling MR, Walton MS (2006) Dictated by media: conservation and technical analysis of a 1938 Joan Miró canvas painting. In: Saunders D, Townsend J, Woodcock S (eds) The object in context: crossing conservation boundaries: contributions to the Munich congress, 28 Aug–1 Sept 2006. IIC, London, pp 62–68

    Google Scholar 

  • Osmond G (2012) Zinc white: a review of zinc oxide pigment properties and implications for stability in oil-based paintings. AICCM Bulletin 33:20–29

    Article  Google Scholar 

  • Osmond G (2014a) Zinc oxide-centred deterioration of modern artists’ oil paint and implications for the conservation of twentieth century paintings. Ph.D. thesis, University of Queensland, Brisbane

    Google Scholar 

  • Osmond G (2014b) Zinc white and the influence of paint composition for stability in oil based paints. In: Van den Berg KJ, Burnstock A, de Tagle A, de Keijzer M, Heydenreich G, Krueger J, Learner T (eds) Issues in contemporary oil paints. Springer, Cham, pp 263–281

    Google Scholar 

  • Osmond G, Keune K, Boon J (2005) A study of zinc soap aggregates in a late 19th century painting by R.G. Rivers at the Queensland Art Gallery. AICCM Bull 29:37–46

    Article  Google Scholar 

  • Osmond G, Boon JJ, Puskar L, Drennan J (2012) Metal stearate distributions in modern artists’ oil paints: surface and cross-sectional investigation of reference paint films using conventional and synchrotron infrared microspectroscopy. Appl Spectrosc 66(10):1136–1144

    Article  CAS  Google Scholar 

  • Osmond G, Ives S, Dredge P, Drennan J, Puskar L (2013) From porcelain to pimples: a study of synchrotron sourced infrared spectroscopy for understanding the localised aggregation of zinc soaps in a painting by Sir Frederick Leighton. Poster presented at the 7th international workshop on infrared microscopy and spectroscopy with accelerator based sources, Lorne, 10–14 Nov 2013

    Google Scholar 

  • Osmond G, Ebert B, Drennan J (2014) Zinc oxide-centred deterioration in 20th century Vietnamese paintings by Nguyễn Trọng Kiệm. AICCM Bull 34:4–14

    Article  Google Scholar 

  • Poli T, Piccirillo A, Nervo M, Chiantore O (2019) Aging of natural resins in presence of pigments: metal soaps and oxalates formation. In: Casadio F, Keune K, Noble P, Van Loon A, Hendriks E, Centeno S, Osmond G (eds) Metal soaps in art: conservation and research. Springer, Cham, pp 143–154

    Google Scholar 

  • Raven L, Bisschoff M, Leeuwestein M, Geldof M, Hermans JJ, Stols-Witlox M, Keune K (2019) Delamination due to zinc soap formation in an oil painting by Piet Mondrian (1872–1944). In: Casadio F, Keune K, Noble P, Van Loon A, Hendriks E, Centeno S, Osmond G (eds) Metal soaps in art: conservation and research. Springer, Cham, pp 345–357

    Google Scholar 

  • Robinet L, Corbeil MC (2003) The characterization of metal soaps. Stud Conserv 48(1):23–40

    Article  CAS  Google Scholar 

  • Rogala D, Lake S, Maines C, Mecklenburg M (2010) Condition problems related to zinc oxide underlayers: examination of selected abstract expressionist paintings from the collection of the Hirschhorn Museum and Sculpture Garden, Smithsonian Institution. J Am Inst Conserv 49(2):96–113

    Article  Google Scholar 

  • Rosi F, Cartechini L, Monico L, Gabrieli F, Vagnini M, Buti D, Doherty B, Anselmi C, Brunetti BG, Miliani C (2019) Tracking metal oxalates and carboxylates on painting surfaces by non-invasive reflection mid-FTIR spectroscopy. In: Casadio F, Keune K, Noble P, Van Loon A, Hendriks E, Centeno S, Osmond G (eds) Metal soaps in art: conservation and research. Springer, Cham, pp 175–192

    Google Scholar 

  • Saunders D, Kirby J (2004) The effect of relative humidity on artists’ pigments. Natl Gallery Tech Bull 25:62–72

    Google Scholar 

  • Schilling MR, Carson DM, Khanjian HP (1999) Gas chromatographic determination of the fatty acid and glycerol content of lipids. IV. Evaporation of fatty acids and the formation of ghost images by framed oil paintings. In: Bridgland J, Brown J (eds) Preprints of the ICOM committee for conservation12th triennial meeting, Lyon, 1999. James and James, London, pp 242–247

    Google Scholar 

  • Schilling MR, Mazurek J, Learner TJS (2007) Studies of modern oil-based artists’ paint media by gas chromatography/mass spectrometry. In: Learner TJS, Smithen P, Krueger JW, Schilling MR (eds) Modern paints uncovered, Tate Modern, London, 16–19 May 2006. The Getty Conservation Institute, pp 129–139

    Google Scholar 

  • Shimadzu Y, van den Berg KJ (2006) On metal soap related colour and transparency changes in a 19th century painting by Millais. In: Boon JJ, ESB F (eds) Reporting highlights of the de Mayerne Programme. Netherlands Organisation for Scientific Research (NWO), The Hague, pp 43–52

    Google Scholar 

  • Shimadzu Y, Keune K, van den Berg KJ (2008) The effects of lead and zinc white saponification on surface appearance of paint. In: Bridgland J (ed) Preprints of the ICOM committee for conservation: preprints of the 15th triennial meeting, New Delhi, 22–26 Sept 2008. Allied Publishers Pvt Ltd, pp 626–632

    Google Scholar 

  • Standeven H (2011) House paints, 1900–1960: history and use. Getty Conservation Institute, Los Angeles

    Google Scholar 

  • Suryanarayana NP (1970) Critical pigment volume concentration of some oxide pigments. J Colour Soc 9(2):2–6

    CAS  Google Scholar 

  • Sutherland K, Price BA, Lins B, Passeri I (2013) Oxalate-rich surface layers on paintings: implications for interpretation and cleaning. In: Mecklenburg MF, Charola EA, Koestler RJ (eds) New insights into the cleaning of paintings. Proceedings from the cleaning 2010 international conference Universidad Politecnica de Valencia and Museum Conservation Institute. Smithsonian Institution Scholarly Press, pp 85–87

    Google Scholar 

  • Theobald Clark S, Osmond G (2016) The materials and techniques of William Robinson. AICCM Bull 37(2):51–65

    Article  Google Scholar 

  • van den Berg J, van den Berg K, Boon J (1999) Chemical changes in curing and ageing oil paints. In: Bridgland J (ed) Preprints of the ICOM committee for conservation 12th triennial meeting, Lyon, pp 248–253

    Google Scholar 

  • van den Berg KJ, Burnstock A, Schilling M (2019) Notes on metal soap extenders in modern oil paints: history, use, degradation and analysis. In: Casadio F, Keune K, Noble P, Van Loon A, Hendriks E, Centeno S, Osmond G (eds) Metal soaps in art: conservation and research. Springer, Cham, pp 331–343

    Google Scholar 

  • van der Weerd J, Gelddof M, van der Loeff LS, Heeren R, Boon J (2003) Zinc soap aggregate formation in ‘Falling leaves (les Alyscamps)’ by Vincent van Gogh Zeitschrift für. Kunsttechnologie und Konservierung 17(2):407–416

    Google Scholar 

  • Van Gorkum R, Bouwman E (2005) The oxidative drying of alkyd paint catalysed by metal complexes. Coord Chem Rev 249:1709–1728

    Article  Google Scholar 

  • Winter G, Whittem RN (1950) Fluorescence and photo-chemical activity of zinc oxides. J Oil Colour Chem Assoc 33:477–483

    Google Scholar 

  • Wöll C (2007) The chemistry and physics of zinc oxide surfaces. Prog Surf Sci 82:55–120

    Article  Google Scholar 

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Acknowledgments

Sophie Theobald Clark, Marion Mecklenburg, Catherine Nunn, Bettina Ebert, Paula Dredge, Jaap Boon, Katrien Keune, Joen Hermans, Kate Helwig, Anne Carter, Amanda Pagliarino, Nicole Tse and John Drennan have all generously shared samples and information or otherwise supported my research over many years. I acknowledge the facilities and the scientific and technical assistance of the Australian Microscopy and Microanalysis Research Facility at the Centre for Microscopy and Microanalysis, University of Queensland, and at the Infrared Microspectroscopy Beamline at the Australian Synchrotron, Victoria, Australia. QUT facilitated the William Robinson Research Project. The continuing support of QAGOMA is gratefully acknowledged.

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Authors and Affiliations

  1. Queensland Art Gallery/Gallery of Modern Art, Brisbane, Australia

    Gillian Osmond

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  1. Gillian Osmond
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Correspondence to Gillian Osmond .

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Editors and Affiliations

  1. The Art Institute of Chicago, Chicago, IL, USA

    Francesca Casadio

  2. Conservation Department, Rijksmuseum, Van’t Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands

    Katrien Keune

  3. Conservation Department, Rijksmuseum, Amsterdam, The Netherlands

    Petria Noble

  4. Conservation Department, Rijksmuseum, Amsterdam, The Netherlands

    Annelies Van Loon

  5. Programme Conservation and Restoration of Cultural Heritage, University of Amsterdam, Amsterdam, The Netherlands

    Ella Hendriks

  6. Department of Scientific Research, The Metropolitan Museum of Art, New York, NY, USA

    Silvia A. Centeno

  7. Queensland Art Gallery/Gallery of Modern Art, Brisbane, Australia

    Gillian Osmond

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Osmond, G. (2019). Zinc Soaps: An Overview of Zinc Oxide Reactivity and Consequences of Soap Formation in Oil-Based Paintings. In: Casadio, F., et al. Metal Soaps in Art. Cultural Heritage Science. Springer, Cham. https://doi.org/10.1007/978-3-319-90617-1_2

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