East German artists' materials

Sabine Cotte <sabinec [at] ozemail__com__au> writes

>Does anyone know about the type of paint used by artists in East
>Germany and Russia in the late 1970s? I am conserving a 1978
>painting by a North Vietnamese artist and I've been told that he
>used East German paint, mixed sometimes with Russian paint. ...

In collaboration with Bettina Ebert, Senior Paintings Conservator at
Asiarta Foundation in Kuala Lumpur, I have recently been
investigating samples from North Vietnamese paintings by Nguyen
Trong Kiem from the late 1970s - 1980. These belong to the Witness
Collection, currently based in Malaysia.

Substantial research into two earlier paintings by this artist has
also occurred within the conservation training program at University
of Northumbria by Sally MacMillan (2007) and Bettina Ebert (2008).
Sally's research included an investigation of Soviet and East German
tube paints obtained from contemporaries of Kiem, as examples of
typical Government-issue paints used by North Vietnamese artists
during this period.

Analysis showed the paints to be (raw) linseed oil based with
traditional and modern mineral pigmentation and some organic
pigments typically consistent with labelling on the tubes.  Fillers
were typically barium sulfate and sometimes aluminium silicates or
quartz.  This analysis is supported by what has been observed in
paintings.

Although not mentioned specifically in the analysis of the tube
paints (no white paints were included), the defining feature of
virtually every paint layer in 5 of Kiem's paintings dated 1963-1980
is the predominance of zinc oxide.  The zinc oxide is present in a
variety of grades and also variously in combination with lead white,
barium sulphate, chalk or alone.  Titanium white is occasionally
present as a minor component.

The reactivity of zinc oxide in oil based media in combination with
severe exposure related hydrolysis of the paintings has resulted in
extensive zinc soap formation.  It is possible that zinc stearate
may also have been used in some paint formulations, however it is
clear substantial zinc stearate and other zinc carboxylates have
formed in situ.

One of Kiem's paintings (from 1963) also includes large masses of a
hydrated zinc sulphate which have been described in

    Bettina Ebert, Sally MacMillan Armstrong, Brian Singer and Nicky
    Grimaldi. "Analysis and Conservation Treatment of Vietnamese
    Paintings". Preprints of ICOM-CC Lisbon 2011

Assuming the painting you describe is also based on zinc white, the
granular texture may relate to similar zinc sulphate masses (which
would be water soluble) but could equally reflect aggregated masses
of zinc stearate with or without remineralised centres, typically
zinc carbonates or sulfates.  My analysis of zinc oxide centred
deterioration in these 5 paintings by Kiem was recently presented at
the 2012 AICCM Paintings Group + 20th Century in Paint Symposium
"The meaning of materials in modern and contemporary art" (Brisbane
10-11 December 2012), and will be published with co-authors Bettina
Ebert and John Drennan in the Postprints intended for publication
during 2013.

Gillian Osmond
Conservator Paintings
Queensland Art Gallery/Gallery of Modern Art
PO Box 3686
South Brisbane
Queensland 4101 Australia


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                  Conservation DistList Instance 26:30
                 Distributed: Monday, December 17, 2012
                       Message Id: cdl-26-30-002
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