Conservation Prof.Martens Flashcards
What is varnish damage and how do you remove it?
Varnish damage: oxidation - turning yellow, running blue, blinded varnish, excrement of flies, test window removal varnish central panel.
Varnish removal: Dry mechanical cleaning with eraser (or by rotating movements with fingers), overcleaned varnish, mechanical removal with scalpel, varnish removal with solvent.
Why is magnification useful when looking at paintings?
You are able to see small details the naked eye cannot pick up
What are some risks of degradation for supports?
Fungi
Insects
Worm holes
Climate
What are the types of retouching?
-oil retouching
-resin retouching
-resin-oil retouching
retouching with aqueous solutions
- Aquarel retouching
- Gouache retouching
- Egg tempera retouching
retouching with synthetic media
-acrylic resin retouching (e.g. Paraloïd B72 dissolved in toluene or xylene)
- Polyvinyl acetate retouching (PVAc) (e.g. Mowilith dissolved in ethanol)
-polyvinyl alcohol retouching (PVAl) (e.g. Mowiol dissolved in water)
- Keton-resin retouching
What are blisters?
Paint layer lifts forming air bubbles
What are some flaking in paintings?
Flaking types: On panel and canvas, disintegration of binding medium, cupping (migration of moisture from exterior wall through canvas and paint layers), blisters on transferred canvas, heat damage, chemical damage.
What do conservators not do?
Conservators do not create new cultural or historical goods, other professions do replicas of objects that have been lost.
What does the training and education of a conservator-restorer include?
Knowledge of history of art and civilizations, methods of research and documentation, knowledge of technology and materials, conservation theory and ethics, conservation-restoration history and technology, chemistry, biology and physics of deterioration processes and of conservation methods
What is cupping?
Migration of moisture from exterior wall through canvas and paint layers
Part of paint layer becomes concave
What causes delaminating?
-Movement in support by fluctuating RH
-Movement in support by fluctuating temperature
-Wrong painterly structure
-Colouring layers getting brittle by ageing
-Decreasing adhesion of medium by ageing through
micro-organisms
-Wrong treatment (e.g. wrong lining)
-Mechanical impact
What is the cleaning controversy in conservation?
Removing varnish is considered problematic (mostly in Italian school) as it can remove top layers of paint.
What are the limits of a conservator’s expertise?
Conservator must work within the limit of their expertise and seek help from others when they lack knowledge
How far does different imaging techniques penetrate?
How to clean loosely hanging canvases?
Cleaning reverse: cleaning under air pressure, deformation caused by textile patches, removing old lining, facing, vacuum hot-table, treatment of wrinkles, treatment of tears (textile patch with starch or wax), gluing fibre under microscope.
What are some types of retouching?
- Oil retouching
- Resin retouching
- Resin-oil retouching
- Retouching with aqueous solutions
Aquarelle retouching
Gouache retouching
Egg tempera retouching - Retouching with synthetic media
Acrylic resin retouching (e.g., Paraloïd B72 dissolved in toluene or xylene)
Polyvinyl acetate retouching (PVAc) (e.g., Mowilith dissolved in ethanol)
Polyvinyl alcohol retouching (PVAl) (e.g., Mowiol dissolved in water)
Keton-resin retouching
What are some forms of degradation?
Rimpling
Discolouring
Increasing transparency through formation of led soaps
Bleeding
Bleaching
Darkening
Waning
Premature cracks
Age cracks
Cracks caused by stretcher
Spiral cracks from bumping into canvas
Fake cracks - incisions
Fake cracks - paint baked in hot heat to make it look older
What is a textile patch on a canvas?
Repair damaged canvas with a textile patch
How can you repair wormholes in a wooden panel?
Fill holes with epoxy resin
It does discolour the wood
What is filler made from?
Glue based filler (e.g. glutine glue and chalk)
Emulsion filler (glue – oil - chalk)
Oil filler (oil – leadwhite or chalk = mastic)
Wax-resin filler
Beva 371-chalk filler
Contains synthetic resin and paraffine desolved in tolueen and gazoline
synthetic resin filler
What are some types of reinforcements for wooden panels?
What is the purpose of ICOM and ICOM CC?
Action aimed at protecting cultural heritage, ensuring expansibility for future generations, and clarification of language between conservator, restaurateur, and curator.
How can flaking paint be fixed to support?
Injecting glue behind paint layer and then pressing down paint layer to fasten
What is varnish cracking?
When the varnish layer cracks on top of the paint layer
There can be cracks in the paint layer and the varnish layer
How can a support be treated when infested with fungi or insects?
Inject with poison
How common is interdisciplinary work in conservation?
Interdisciplinary work with conservation has become more common in later years even though it has been common in other fields for many years.
What is a luxmeter?
Instrument that measures light
How can a canvas be repaired?
Sewing ripped part
Applying patch with starch of wax
Glueing fibres under stereo microscope
Woven in mending of hole
What are ideal properties of glue in conservation of supports?
- minimal negative ageing
- tensionless hardning
- insensitive to climate influence
- cold usage
- glued join cannot be stronger than the original panel
Different types
Glutine glue
Artificial glue (epoxy)
How is the document idealistic and vague?
The document says little about interventions itself, doesn’t talk about treatment matters, provides little protection for the conservator and doesn’t mention reversibility of conservation.
How can a counterfeit painting be spotted?
Fake cracks
Fake signature over cracks
What is heat damage?
When painting is heated over 75 C
How do you use preventative conservation?
By controlling humidity and temperature to stay the same
Packaging safely during trips
Registration, storage, handling, safety, environmental, emergency planning, public awareness
Aim to slow down decay
How can you counter UV?
UV absorbing glass, film or varnish
Curtains
Use Incandescent and halogen lights - no UV
What is structuring?
Creating texture on filler to mimic the texture of paint layer
What is disintegration of binding medium?
When parts of the paint layer falls off
What is the ideal climate for a wooden panel?
Humidity: RV 58%
Temperature: 18° C.
Hanging:
Careful against exterior walls
No direct sunlight
Not near heating
Adapted to weight
What are climate-boxes?
Box for object with controlled climate inside
What factors should you have in mind when handling art?
- Climate control
Ideal for wooden panels: RV 58%. Temperature 18C.
In practice: RV 50% á 60%. - Hanging
Careful against exterior walls
No direct sunlight
Not near heating
Adapted to weight - Properties of glue
Minimal negative ageing
Tensionless hardening
Insensitive to climate influence
Cold usage
Glued join cannot be stronger than the original panel - Glutine glue and artificial glue (epoxy)
- Impregnation, chemical flattering
- Mixture of chemical and shellac
Wood expends
Wood flattened under pressure
Hardens
Shellac: evaporates
What are the dangers of flies and paintings?
Fly excrement cause stains
What is delaminating?
Croissant effect
What are the risks of a textile patch?
It can deform the canvas when ageing
How often and why do you need to change varnish?
Every 60 years
Varnish oxidises - It becomes brownish yellowish
How do conservation practices differ between countries?
Different techniques work on different paintings and what works on Italian paintings may not work on Flemish paintings.
What is ICOM?
International council of museum, founded after WW2, in Paris
How can the reverse of a canvas be cleaned?
With air pressure
Using a scraper
Using a cloth
Using a feather/brush
What is non-integrated retouching?
When the new paint does not math in texture or cracks
What is an Electric thermos hydrographs
Measures temperature and humidity electrically
What is chemical damage?
When chemicals destroy painting
What is flaking?
Entire paint layer and ground lifts form support
What is restoration?
o If there is a hole in a painting and you repair it the painting is restored
o You add something to the painting that was not there before
Goal is to take object as close to the original state as possible
What is the goal of preventative conservation?
Goal is preventing future losses and disturbance of objects
What is blinded varnish?
When varnish cracks and the edges become white
What is the dangerous part of light?
Ultra Violet radiation (UV)
How has the use of materials changed in conservation-restoration?
Until 1970s non-reversible materials were used, now materials that are reversible are used and everything that is added should be able to be removed.
What are some degradations and Damages in Paintings?
Degradation types: Rimpling, Discolouring, Bleeding, Bleaching, Darkening, Waning, Premature cracks (by walnut oil), age cracks, cracks caused by stretcher, spiral from cracks visible in raking light, incised, fake cracks, fake cracks - baked, delamination.
How can wrinkles be removed from canvas?
Vacuum hot table
Stretching (like parchment)
What is facing?
Glueing Japanese (washi) paper to paint layer to protect it when restoring the back
What is impregnation chemical flattening
Mixture of chemical and shellac
- Wood expands
- Wood flattened under pressure
- hardens
- shellac: evaporates
What are some types of fillers?
- Glue based filler (e.g., glutine glue and chalk)
- Emulsion filler (glue – oil – chalk)
- Oil filler (oil – lead white or chalk = mastic)
- Wax-resin filler
- Beva 371-chalk filler
Contains synthetic resin and paraffined dissolved in tolueen and gasoline synthetic resin filler - Polyvinylalkohol, polyvinylacetate and polyacryl
What are some different types of cradles?
How is the treatment of an object determined?
How much treatment is done is based on when the values of all previously mentioned factors are the highest. Make detailed reports and use the most appropriate technique.
What are some important properties of a canvas?
- Ageing by oxidation
- Sensitive to contact with metal
- Sensitive to drying oils
- Sensitive to UV-radiation
- Sensitive to some pigment and dyes
- Contains cellulosis: infection by micro-organisms
- Sensitive to acid
- Reacts strongly on mechanical tension
- Hygroscopic
What is neutral tone retouching?
Painting missing parts with one colour
What is ICOM CC?
Conservation part of ICOM, produced code of ethics in 1984 to establish rules for conservation and push for protecting the title of conservator
What methods can varnish be removed with?
Dry or wet method
Wet method – solvents dissolve varnish to remove it
What is thermal treatment?
Using heat to kill fungi and insects
What is silica gel?
Draws in moisture to prevent higher humidity around it
How do the conservation practices differ between museums and the art market?
Museums focus on preserving the object while art market focuses on making the object look better.
What are some measurement instruments?
Thermo-hydro meter
Electric thermos hydrographs
Climate-boxes
Condition showcases
What are some types if solvents?
Carbon compounds:
- White spirit
- Tolunene and xylone
- Turpentine
- Alcohol - ethanol, isopropanol
- Acetone
- Ethyl acetate
- Ethyl glycol, diethyl ether
Mixtures of carbon compounds
Bases and acids
Enzymes and resin soaps
What is filler?
Used to fill holes paint layer to create even surface
What is the role of conservators in preservation of objects?
Conservators see themselves as doctors of the objects. Diagnosis determines the best treatment, treat and work with art historians and scientific people in larger projects. A lot of documentation by imaging the objects.
What are condition showcases?
Box for object with controlled climate inside
What is varnish oxidisation?
When varnish become discoloured
Yellow or blue
Blue discolour: Presumably by air pollution
What treatment can be done on reverse of canvas?
Wax or oil
What values can an object have?
artistic, religious, historic, scientific, cultural, social, or economic value
THER IS NO HIERARCHY AMONG VALUES
What is ratteggio or rigatini technique
Retouching with multiple lines
What are the two methods for finding a useable solution to remove varnish?
o Empirical method – rub solvent on side of painting to see if it dissolves
o Scientific method – analyse sample of varnish in lab to see which solvent should be used
What is neutral retouching?
Make a color of the colour around the hole, fill in the hole with that color
Works for Italian paintings
How can varnish be removed?
Mechanically:
- With eraser
- With fingers
- With scalpel
With solvents:
- Carbon compounds
- Mixtures
- Bases and acids
- Enzymes and resin soaps
