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The Getty Conservation Institute
Eric Hansen
Eilene Sadoff
Rosa Lowenger
Period of Activity: 1988-1990
Project Abstract
The purpose of this investigation was to review with conservators
methods and materials used in the consolidation of ethnographic
surfaces and surfaces with high pigment volume concentrations (PVC),
and to investigate alternate approaches to consolidation.
Primary Publications
Hansen, E., E. T. Sadoff, and R. Lowinger, "A Review of Problems
Encountered in the Consolidation of Paint on Ethnographic Wood Objects
and Potential Remedies," Proceedings of the ICOM 9th Triennial Meeting,
Dresden, Vol. 1, August 1990, pp. 163-168.
ABSTRACT-Problems encountered in the consolidation of paint on
ethnographic wood objectsare reviewed, based upon the literature
and surveys of North American ethnographic conservators. Significant
consolidation may require a large quantity of resin, which affects
the appearance of the paint. Changes in appearance may be minimized
by selecting either particular application procedures or resins
that are effective in lower concentrations. The solution properties
(volatility, viscosity, surface tension) may be as important as,
or more important than, the physical properties of the dried resin.
As removal of the resin used to consolidate a fragile deteriorated
paint is unlikely, the aging characteristics are of primary importance
in the choice of resins. Insoluble thermosetting resins (diisocyanates,
epoxies) are considered due to their high strength in low concentrations,
compared to thermoplastic resins.
Hansen, E., and E. Sadoff "The Use of Facsimiles in Research on
the Conservation of Painted Ethnographic Wood Objects," Paper presented
at the WAAC, Honolulu, Hawaii, October 1989.
ABSTRACT-Facsimiles produced in a laboratory can simulate, to certain
degrees, problematic painted wood surfaces of ethnographic objects.
Wood objects painted with clays or ochres bound with an insufficient
amount of binder or an ineffective binder often have surfaces of
loose, flaking, or powdering paint. Facsimiles are being used at
GCI to research new materials and methods for the conservation of
these objects, and also to determine the causes of deterioration.
The paint manufacturing technologies of cultures (Oceanic and African)
whose objects often exhibit problems with the painted surfaces are
being considered in the production of these facsimiles. The cracking
patterns and the flake morphology of the facsimiles are under study
to explore a possible relationship with the pigment and binder type,
the method of paint application, movement of the wood substrate
(resulting from fluctuations in relative humidity), or any possible
combination of these three. These patterns could then provide visual
clues to the underlying causes of deterioration. Strategies for
consolidating or readhering porous, flaking paint without affecting
a matte appearance are also presented.
Hansen, E., and R. Lowinger, "Materials and Methods for Consolidating
Paint on Ethnographic Objects," WAAC 1989 Conference, Catalina Island,
California, October 15-17.
ABSTRACT-This paper presents materials and methods for consolidating
paint typical of that found on ethnographic objects. Sources of
information include surveys of ethnographic conservators in the
United States, results of workshops conducted with the participants
of the Getty Conservation Institute (GCI) Training Course on the
Consolidation of Painted Ethnographic Objects (Conservation at the Getty)
Institute (GCI), questionnaires sent to selected ethnographic conservators
in the United States, Canada, and Australia, research conducted
in the Scientific Program of the GCI, and consultation with scientists
active in the fields of conservation or coatings. A major problem
encountered in the consolidation of paint on ethnographic objects
is the consolidation of flaking porous or crumbling paint, powdering
surfaces or multiple layers of paint without altering the appearance.
The following methods are reviewed in respect to specific problems
with a painted surface: different application procedures for solutions,
reforming of polymer films by heat or solvent, use of matting agents,
high-viscosity solutions, consolidation and adherence of paint in
separate steps, saturation of porous flakes with hydrophobic solvents
and adhering with aqueous emulsions, solutions with low-volatility
solvents, saturation of the working atmosphere with solvent fumes,
use of surfactants, prewetting of surfaces, multiple applications
of dilute solutions, relaxation of brittle surfaces with high humidity,
application of solutions through a permeable facing, adjusting solvent
polarity, subsequent surface matting, and methods for consolidation
of friable, flaking surfaces without forming a coherent film.
Hansen, E., and R. Lowinger, "Investigations into Techniques for
the Consolidation of High Pigment Volume Concentration Paint at
the Getty Conservation Institute," WAAC Newsletter, Vol. 12, Nš
3, September 1990, pp. 13-16.
ABSTRACT-The problems encountered in the consolidation of painted
ethnographic objects were reviewed in preparation for an advanced
training course for ethnographic conservators conducted at the Getty
Conservation Institute, June 11 to June 29, 1990, "The Consolidation
of Painted Ethnographic Objects." The course was developed under
the direction of Sue Walston, coordinator for the ICOM Ethnographic
Objects Working Group and previously Head of Materials Conservation
at the Australian Museum. This article describes the specific problems
encountered.
Hansen, E. F., E. T. Sadoff, and R. Lowinger, "A Review of Problems
Encountered in the Consolidation of Paint on Ethnographic Wood Objects
and Potential Remedies," Preprints, ICOM 9th Triennial Meeting,
Dresden, Vol. 1, August 26-31, 1990, pp. 163-168.
ABSTRACT-Problems encountered in the consolidation of paint on
ethnographic wood objects are reviewed, based upon the literature
and surveys of North American ethnographic conservators. Significant
consolidation may require a large quantity of resin which will affect
the appearance of the paint. Changes in appearance may be minimized
by selecting either particular application procedures or resins
that are effective in lower concentrations. The solution properties
(volatility, viscosity, surface tension) may be as important as,
or more important than, the physical properties of the dried resin.
As removal of a resin used to consolidate a fragile deteriorated
paint is unlikely, the aging characteristics are of primary importance
in the choice of a resin. Insoluble thermosetting resins (diisocyanates,
epoxies) are considered due to their high strength in low concentrations,
compared to thermoplastic resins.
Hansen, E., R. Lowinger, and E. Sadoff, "Consolidation of Objects
in a Solvent Vapor Saturated Atmosphere: A New Technique for Minimizing
Changes in Appearance," Paper presented to the Objects Specialty
Group, American Institute for Conservation Annual Meeting, Richmond,
Virginia, 1990.
ABSTRACT-Changes in appearance of a matte powdering clay or ochre
paint which results from consolidation with a solution of a thermoplastic
resin include darkening, discoloration, or increased glass. These
may be minimized by applying the consolidant in an atmosphere saturated
with vapors of the solvent used to dissolve the resin. In addition
to maintaining the original appearance of the object, other benefits
include the absence of a tide line and greater penetration of the
solution for improved adhesion of the consolidated paint to the
substrate. The low cost of the plastic glove bag used to maintain
the vapor saturated atmosphere and the portability of the system
make it easy and inexpensive to use.
At the present time, we are limiting the use of this technique
to objects, or areas of objects, which are not sensitive to solvent
vapors. Five percent solutions in acetone of Acryloid B72 and poly(vinyl
acetates) yield results as effective as those found with diethylbenzene,
without the problems associated with DEB. These include long-term
solvent retention and noxious properties, among others. We believe
this technique is considerably promising for two areas of materials:
clay, ochre, ceramic, terracotta, brick, or other powdering and/or
crumbling inorganic surfaces with little potential for solvent interaction;
and flexible objects such as baskets, painted wood, etc., where
a more flexible polymer than B72 is desired. The theoretical basis
for the observed phenomena is presented along with the results of
consolidating ochre or clay with B72 or PVAC in solutions of acetone,
toluene, and ethanol.
Hansen, E., R. Lowinger, and E. Sadoff, "Consolidation of Porous
Paint in a Vapor Saturated Atmosphere: A Technique for Minimizing
Changes in the Appearance of Matte, Powdering Surfaces," Journal
of the American Institute for Conservation, Vol. 32, 1993, pp. 1-14.
ABSTRACT-A technique is described for consolidating matte, low-gloss,
powdery surfaces without darkening the colors. When resins are applied
for consolidation of such matte surfaces, darkening of the colors
may occur because of an increase in the gloss of the surface, due
to the formation of a film over the surface to be protected. The
technique outlined involves the application of a stable thermoplastic
resin solution in an atmosphere containing a very high concentration
of the solvent used to dissolve the resin, thus slowing solvent
evaporation and allowing the resin to penetrate into and around
the exposed pigment particles. In addition to retaining the matte
appearance of the object, "tide lines" are prevented and adhesion
of the pigment may be improved.
Hansen, E. F., P. Volent, M. H. Bishop, and R. Lowinger, "The Consolidation
of Matte, Porous Paint: Examples from Ethnographic Objects and Contemporary
Works of Art," AIC Paintings Specialty Group Postprints, Presented
at the 21st Annual Meeting of the American Institute for Conservation
of Historic and Artistic Works, Denver, Colorado, June 5, 1993,
pp. 67-71.
ABSTRACT-Matte, porous paint, highly friable and difficult to consolidate
without darkening and discoloring, is found in a wide range of objects.
Some physical and optical properties of this type of paint, as a
result of high pigment volume concentration and diffuse surface
reflectance, are presented with a stress on ramifications for treatment
parameters. The problems encountered in transferring the results
of controlled laboratory studies into effective conservation treatment
procedures are also discussed in reference to painted ethnographic
wood objects and contemporary works of art on paper (with a cautionary
note on undesirable solvent sensitivity).
Hansen, E. F., and M. H. Bishop, "An Interdisciplinary Bibliographic
Approach to a Complex Conservation Problem: The Consolidation of
Matte Paint," Working Group 4, Preprints, Vol. 1, ICOM Committee
for Conservation 10th Triennial Meeting, Washington, D. C.,
August 22-27, 1993, pp. 189-194.
ABSTRACT-Describes a literature survey, occasioned by a research
project into the problems of consolidating matte, friable paint,
with an emphasis on ethnographic objects. Available bibliographies
and databases, such as BCIN, CAS, and Rapra, provided few references.
Although few references were initially located, isolating the problem's
physical nature and understanding its interdisciplinary aspects
aided in identifying and compiling a wide variety of literature
of direct relevance to the problem and useful to the conservator
in designing treatment strategies. Annotated references to this
literature have been gathered into a topical supplement to Art and
Archaeology Technical Abstracts (AATA), to be published autumn 1993.
The organization, sources, and unique aspects of this bibliography
are described in this paper, as is the research methodology used
to assemble the references.
Hansen, E., and M. Bishop, "The Conservation of Painted Archaeological
and Ethnographic Objects," The Getty Conservation Institute Newsletter,
Winter 1993, Vol 8, Nš 1, p. 14.
ABSTRACT-Discusses the relatively undeveloped state of conservation
for archaeological and ethnographic objects and the inherent fragility
of these objects. Continues to describe the course on the "Consolidation
of Painted Ethnographic Objects" given by the Training Program of
the GCI and the research and publications that resulted from the
course. Gives a brief description of the special supplement to AATA,
Matte Paint: Its History and Technology, Analysis, Properties, Deterioration
and Treatment, with Special Emphasis on Ethnographic Objects, as
an attempt to begin to address specific issues in this important
area.
Hansen, E. F., and P. Volent, "Technical Note on Solvent Sensitivity
Testing of Objects for Treatment in a Vapor-Saturated Atmosphere"
Journal of the American Institute for Conservation, 1994, 33:315-316.
ABSTRACT-None available.
Hansen, E. F., S. Walston and M. H. Bishop, "Matte Paint: Its Technology
and History, Analysis, Properties, Deterioration and Treatment with
Special Emphasis on Ethnographic Objects; a Critical, Annotated
Supplemental Bibliography to Art and Archaeology Technical Abstracts"
(Los Angeles, CA: The Getty Conservation Institute and the International
Institute for Conservation) 1994.
ABSTRACT-None available.
Hansen, E. F. and M. H. Bishop, "Factors Affecting the Retreatment
of Previously Consolidated Matte Painted Wooden Objects" in Painted
Wood: History and Conservation (Preprints of the November, 1994
Symposium at Colonial Williamsburg) in press.
ABSTRACT-None available.
Matte Paint: Its History and Technology, Analysis, Properties,
Deterioration, and Treatment, with Special Emphasis on Ethnographic
Objects, Hansen, E. F., S. Walston, and M. H. Bishop (eds.), In
Art and Archaeology Technical Abstracts, The (Conservation at the Getty)
Institute, Supplement 30, Nš 3, August, 1994.
ABSTRACT-Although the primary emphasis in this bibliography, a
supplement to Art and Archaeology Technical Abstracts, is on ethnographic
objects, it also includes information on the deterioration and conservation
of matte paint on immovable objects, including painted walls and
architectural ornamentation, and on the conservation of unpainted
matte areas, such as painted wall and architectural ornamentation.
The occurrence and treatment of architectural decoration of clay
or stucco in prehistoric Mesoamerica are also discussed.
This topical bibliography contains more than 1,500 abstracts of
periodical, monographic, and unpublished literature from the fields
of anthropology, conservation, ethnobotany, art history, and coatings
science. In addition, there are a number of abstracts of audiovisual
sources, particularly historic films from early anthropological
studies.
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