Barbáchano
& Beny, experts in the conservation and restoration
of works of art on paper and parchment, explain the technical aspects of properly
framing a work of art in order to guarantee its proper conservation..
Basic
Terminology By
"conservation materials," we
mean those which are indicated for the job at hand and for which we have the necessary
trustworthy scientific and technical data, recommended and approved by institutions
with the capacity to study and homologate them.
Stable
or stability,these terms indicate that a given product or material is not
degradable, that it maintains its characteristics and qualities unalterable. Regarding
challenging climactic conditions, we require that the material not suffer alterations,
or that those which take place are within predictable parameters.
Degradation,
aging, when this occurs in products or materials, normally refers to changes
or losses of flexibility, color, generally darkening or yellowing. Some framing
products can liberate acids or other, unknown, volatile elements which can be
damaging in themselves or when combined with other substances, and in general
lose their specific characters.
Microorganisms,
we are referring to fungus (mold) and bacteria.
Wood,
we include in this chapter both natural woods (oak, pine, beech, etc.) and artificial
woods such as chip boards, plywoods, DM, etc. All of them are very hygroscopic,
capturing and retaining a humidity and dust. They all transmit acidity through
contact and emanations, as well as insects, naturally attracted to wood. The artificial
woods release gases which are dangerous for works of art or can react with the
content of adhesive products or varnishes, generating volatile compounds which
are harmful for the works, not only paper and parchment.
Ignifugous,
which indicates that a given product can burn but not flame up, and can withstand
high temperatures.
Inhibit, protect, in this
case, the damaging effect of light or biological activity.
Lucíphobes,
we refer to the aversion to light which is experienced by most microorganisms
and some insects. In the presence of light the microorganisms do not develop and
insects are repelled.
Hidrofugue, does not
absorb water, rather tends to reject it.
Higroscopic,
more or less, an indicator of a greater or lesser capacity for retaining water.
U.V.,
ultraviolet radiation, Electromagnetic radiation emitted
by light which provokes chemical reactions in the products and materiales which
we use.
Antistatic, the quality
of impeding the formation of static electricity, not attracting dust nor colors,
when they are not fixed, as in the case of pastels, chalks, charcoals, graphites
and crayons. By using antistatic materials the artworks which utilize these techniques
suffer no deterioration due to static electricity which can be generated in glass
or perspex merely by rubbing it with a cleaning cloth. Nowadays there are materials
which have antistatic protection incorporated, and other products which can be
applied which will achieve the same effect in glass and plastics.
Abrasion,
effect which is produced when two surfaces rub together. Abrasives are materials
which we use to produce this effect. We use this term to refer to all the products
and treatments which are used for superficial erasures on paper and parchment
supports.
Reversible, we use this term to
indicate the quality of a product, material or technique which permits reversal
without leaving residues and without causing damage or alterations, whether visible
or not. The following are not considered reversible: all types of silicone whether
applied hot or cold, polivinilic glues, contact adhesives, all auto-adhesive tapes
whether one or two sided, except those which make specific mention of their composition,
indicating their pH grade, as well as the stability of the support and the adhesive.
It should even indicate the reversal system. It can depend upon where or how we
apply an adhesive whether it is reversible or not.
State
of conservation
This is an important chapter, as artworks can arrive
in deteriorated conditions and, depending upon the type of damage
they present, by means of proper framing we can stop, slow or aggravate the process
of degradation. Logically this can condition the type of mounting and for this
reason a framer should have a basic knowledge to permit him to identify different
types of damage, their severity and, if their condition is not good, whether we
should not try to restore the work. A
restoration carried out with the best of intentions but without the necessary
technical knowledge can cause irreversible damage. In these cases it is more professional
to recommend that the client consult a professional restorer.
Intrinsic,
interior, intimate, we use in the description of the causes of deterioration,
when these are originated by internal factors, inherent in the materials from
the moment of their fabrication.
Density,
magnitude which expresses the relation between the mass and the volume of a body.
In the case of framing we can use it when referring to a variety of materials
or products and in the description of tapes and adhesives. Permanent,
the quality of maintaining a given condition without mutation, change, state or
quality, a condition which all the materials used in framing, conservation and
restoration should manifest.
Materials Mylar,
commercial name of polythene teleftalate. Its principal characteristics are: stable
transparent film, antistatic and an inhibitor of ultraviolet radiation and heat
resistent, applied through ultrasound and contact. Linen,
vegetable fiber rich in minimally-hygroscopic cellulose, used for the fabrication
of high quality papers and cardboards.
Cotton,
vegetable fiber also rich in cellulose, more hygroscopic than linen, also used
for the fabrication of high-quality papers and cardboards.
Cardboard,
a product generally high in acidity, a fact which no manufacturer specifies. The
acidity can be transferred by contact or by emanations of gases and is very damaging
to paper and fabric supports and other materials in general. Cardboard designated
"pH neutral" means that both the surface and the interior of the material
have a pH close to 7. Cardboard with an alcaline reserve should have a pH of 7.2
or more, and be clearly marked as to the exact level or reserve which it has.
"Museum-quality cardboards" are made to very high standards, normally
of cotton or linen, with a neutral pH or alcaline reserve and light-and-humidity
stability. Low hygroscopy.
Silica gel, humidity
absorbent material material in the form of pink pebbles which, when saturated
with humidity, change to purple. They can be dried and reused.
Sepiolite,
humidity absorbent material in the form of pebbles. They can also be dried and
reused.
Art-sorb, cardboard support with special
properties for regulating the degree of humidity inside a frame or other closed
construction.
Ageless, oxygen absorber. With
special properties for retaining or absorbing oxygen. Placed inside a frame or
closed construction it diminishes the volume of oxygen, which retards the growth
of microorganisms and insects. Adhesives,
if placed in contact with works of art, or very close to them, should have the
following characteristics: be stable,acid free, permanent, reversible and of low
or medium density. In the case of adhesive tapes the support must meet the same
standards. | |
The
stains on this etching by Chillida were caused by the acidity of the wood used
as backing in the framing process, even though there was a sheet of cardboard
between the wood and the paper and the two never came into physical contact.
The
Changing Framing Tradition
Traditionally
picture framing has only covered two very basic requirements:
- hanging
the artwork on the wall
- enhancing
the esthetic qualities of the picture
The only variable in play was the question of price. In recent years, however,
this concept has been changing due to greater concern on the part of clients,
framers and frame manufacturers for conserving the works of art they are called
upon to frame. This has given rise to the term "Framing for Conservation,"
a concept which has become increasingly important and today has become essential.
Today the owners or people responsible for works of art do not put them into the
hands of just any old framer. They have learned the hard way, through experience,
to demand the highest qualities in handling, products and materials. Control,
Control, Control
In order to do a professional job, we must control
three well-defined aspects: - The
handling, mounting and dismounting of the piece. All of our actions must guarantee
its security and integrity at all times, controlling even the actions of other
technicians who may be involved in the process.
- The
mounting of the frame itself. Our philosophy has as its principal objective the
conservation of the work of art in question, in second place the esthetic aspects
and finally the budget. The basic objectives of a professional framing job are
to not damage the work, to anticipate and prevent those damages which can occur,
and finally to eradicate or minimize the intrinsic deterioration due to the makeup
of the work or its poor state of conservation.
- The
prevention of accidents, both passive and active. This means providing our frames
with defenses against damage from fires, floods, impacts or other causes. To achieve
this it is also necessary to advise clients in matters of transport, placement
and hanging.
There
are no ready-made formulas for framing for conservation, since each work of art
is a world unto itself. What we do have is a methodology based on sound technical
and scientific knowledge of all the elements which intervene in the process: first
of all the work itself, then the materials and products we use, and lastly the
ambiental factors, working procedures and handling.
The
framer who wants to do a correct job needs to know the different types of paper
and parchment, and the characteristics which differentiate them. He also needs
to take into consideration the variety of pictorical techniques, etching and printing
techniques, characteristics of photographs, as well as the characteristics of
inks and pigments and their applications. Only in this way is it possible to predict
the reactions of the materials and products used in the framing process, and their
interrelation with other factors such as humidity, temperture, light and contamination.
"...a
paper's quality is directly related to its date of manufacture; the finest papers
are those of the XVIIIth century..."
Paper
is a substrate generally composed of cellulose fibers (though there are synthetic
papers) the quality of
which is directly related to its date of manufacture; the finest papers are those
of the XVIIIth century, which are referred to as "rag papers." Their
fibers are rich in linen or hemp cellulose, and the adhesives used are usually
of animal origen. Most modern papers are made from cellulose obtained from wood
by chemical procedures,
incorporating synthetic adhesives and other noxious substances. They are generally
of such low quality that some of them self destruct with the mere passage of time.
Though
there are also special modern papers and cardboards made from cotton or linen,
acid free or with an alcaline reserve, which are of excellent quality, some of
them called "permanent," as an indication of their stability and durability. Parchment,
A Special Case
Parchment is a substrate of animal origen, a hide
(though there are imitations in cellulose or synthetic materials) which is treated
to adapt it for writing or coloring. It was used till the XVIth century. Though
it is no longer used, there remain many historic documents, many of them with
rich polychrome illustrations.
Chemical Damages
Chemical degradation
of the hide or paper produces a high acid level which provokes the destruction
of the molecular chains in the skin, increasing its fragility and eventually converting
it to ashes. Acidity is measured in pH degrees, with grades 1-6 being acid, 7
neutral and 8-14 alcaline. The origins of chemical damage can be congenital in
the paper itself when exposed to other factors such as humidity and light. Contaminants
can be transmitted by contact or through gaseous emanations liberated by acidic
materials or uncontrolled chemical reactions among the different elements which
are present: papers, adhesives, solvents, varnishes, cleaning products, cardboards,
woods, etc. Then there are the actions catalyzed by ultraviolet light (UV) in
the presence of ambiental unbalances. Temperature, humidity and contamination
all produce chemical reactions, generating acidity in papers and in colors regardless
of the type of inks or pigments employed. This degradation is often undetectable
during long periods of time: Only a rigorous control of pH level can detect the
level of acidity present. Sometimes the acid shows itself through darkening or
changing the colors of paper and colors, fading, transformation and even the total
disappearance of some colors.
How
Can We Combat Chemical Degradation Through Proper Framing?
- With
exhaustive and reliable information regarding the characteristics of all materials,
products and techniques used in the framing process.
- By
avoiding contact with and emanations from acid substances and hygroscopic materials.
- Utilizing
cardboards and conservation materials of cellulose or cotton of neutral pH or,
in some cases, with an alcaline reserve.
- Protecting
the work from the direct action of light and UV radiations, controlling the type
of light, its intensity, the position of the work with respect to the emission
plane of the light and the use of panels which inhibit radiations.
- Maintaining
a stable equilibrium of the interior humidity of the frame, mainly through the
use of hydrofuge products and humidity regulators.
Biological
Contamination
In general we find three kinds of contamination in
framed work:
- Funguses.
Their presence is detected mainly by the appearance of black, pink or violet stains,
though they can be of any color, and by the extreme fragility of the paper in
the affected zones.
- Insects.
These eat the paper, originating perforations or characteristic holes and furrows
which are harder to detect as they usually occur on the reverse side of the paper
without perforating it completely.
- Biochemical
contamination, called "foxing" manifests itself as sepia-colored stains
of greater or lesser intensity, without a central nucleus and irregular in form.
Foxing appears principally in papers, cardbards, in some colors and even in fabrics.
In order for foxing to develop it requires a propitious biochemical environment:
high humidity; warmth, lack of aeration and food, in this case paper; darkness
and poor hygiene.
How
can we combat foxing through proper framing?
We must create ambiental
conditions which are averse to the growth of foxing inside the frame and, if possible,
outside, as well. Using minimally absorbent materials which are both anti static
and smooth--that is lacking in pores so as to obviate the attraction, absorbence
or retention of dust. When we close the frame hermetically (which impedes access
to dust and atmospheric contamination) we should work in a clean, dust-free space.
If we seal the frame would should leave in its interior a product designed to
regulate the level of humidity. By thus limiting the water content of the interior
environment we can impede the development of microorganisms and insects. If we
also include a material which absorbs oxygen, even to a limited degree, we can
impede the development of all living things.
It
is very important to keep artwork from touching the glass or plexiglass surface.
We should always create an air chamber between the two. This chamber will act
as a regulator of small changes of humidity and temperature, avoiding the formation
of water condensations on the inside of the glass. If condensation should occur,
this chamber will obviate the possibility of stains, contamination by fungus or
damages due to the adhesion of paper, colors or photographic emulsions to the
glass.
Physical
Damage
This can be occasioned by incorrect handling, sometimes accidental,
during the framing process: deformations due to doubling or folding, wrinkles,
rips, perforations and stains. Other damages can be due to the use of products
or techniques which are irreversible , usually due to ignorance or the lack of
proper tools and working conditions.
A great deal of damage is done due to lack of knowledge on the part of the professional
framer who takes risks in carrying out treatments or constructions without the
necessary knowledge and technical resources, or through ignorance of the consequences
of using improvised materials and techniques which lack scientific validity. In
some cases the client himself requests a reduction in the size of the work of
art, either for reasons of economy or in order to make it fit into an existing
frame or space.
"Very
often framers resort to improvised 'restorations' the consequences of which are
very grave for the works of art in question."
How
to Reduce Damage
Due to Improper Handling
Handling damages can
be erradicated almost completely if framers observe conscientious working methods:
well-planned work spaces, well-trained personnell and the necessary technical
resources to assure quality work. Never
Carry Out Work Without
Proper Knowledge and Resources
Proper
conservation criteria require maximum respect for the work of art; it should be
conserved exactly as it was created by the artist. The short, medium and long-term
alterations which we occasion a piece, although a result of ignorance, can impair
a work of art, not only from the esthetic point of view, but in terms of durability.
They can cause irreversible damage in the long run
.
Many clients are utterly
ignorant when it comes to the conservation of their artworks. It is up to the
well-informed professional framer to advise them as to the best way to conserve
them, regardelss of their intrinsic value, whether artistic, documental or simply
sentimental. In the final analysis, the work of professional framers around the
world is of inestimable value in the conservation of the artistic patrimony of
their respective countries. When
we think it necessary to manipulate a work of art to repair damage, however small
it may be, we should turn to a specialist. This specialist can advise us or carry
out the necessary repair with solid guarantees of success. Many damages can be
avoided by keeping in mind the basic principles of conservation. That is to say,
that all the materials and techniques which we use are of consevation quality.
We can resume these factors in four main points. All materials employed should
be: - Stable
(not degradable)
- Acid
free,
- Reversible
- Inocuous
for the work
In
order to insure these conditions we must be well informed as to the technical
characteristics of all the materials and products used in the process of framing. Considerations
Which Should Be Kept
in Mind for the Conservation Framing of Any Type of Work The
work should never enter in contact, front or back, with degradable materials or
acids, such as cardboards, woods, metals, plastics, fabrics or adhesives. All
materials should be anti static (so as not to attract dust) and non porous and
non absorbent so as to prevent water damage. The presence of a high degree of
humidity potentiates the development of chemical and biological processes in paper
and other cellulose-based materials which enter into the framintg process.
We
should never exhibit a work on paper or parchment without the protection of glass
or a similar material which protects it by insulating it from the environment.
Paper and parchment have generally porous surfaces, sometimes very porous, and
the dust which enters their pores can be difficult if not impossible to remove.
Dust carries microscopic grease particles of diverse origin which, in conjunction
with a degree of heat (sometimes simply from our fingers), are fixed on the surface.
The
glass or plexiglass should never touch the work; they should always be separated
by an air chamber which assures the following functions: - It
minimizes and slows exterior changes in temperature and humidity, thus obviating
risk of deformations in the work and possible saturations of humidity on the inside
of the glass.
- It
prevents static electricity from being generated when the glass is rubbed in cleaning,
thus attracting part of the pigments of the work of art and sticking to the inside
surface of the glass.
- It
protects the artworks from the products used for cleaning the glass.
- It
reduces possible impacts and breakages in the case of broken glass.
The
matting of a work of art not only has the function of beautifying the work. Its
main function, from the point of view of conservation is to create the aforementioned
air chamber between the work and the glass.
It is advisable to introduce
into the construction of the frame the necessary regulators of humidity and oxygen,
this when the construction is closed hermetically. The
form of hanging a work of art can also influence a correct conservation. We should
always hang the frame providing it with a slight separation from the wall, sticking
some spacers on the lower part of the frame so as to maintain it separated from
the wall. This permits the circulation of air behind the frame, thus obviating,
especially in humid conditions, the formation of microclimes which facilitate
the development of fungus or the activity of insects.
"If
we add a slight inclination, separating the top of the frame from the wall a bit
more than the bottom, we change the angle of incidence of the light which hits
the work. This not only minimizes the noxious effects of light on the work, but
also reduces annoying reflections when viewing."
More
information from:
Barbáchano
& Beny, S.A.
San Sebastián, 2
28470 Cercedilla (Madrid)
Tel/Fax.: (+ 34) 918 525 550
www.barbachano-beny.com
Our
thanks to Artecuadro magazine (www.artecuadro.com)
for permission
to publish this article. | |
by
Ana Beny & Pedro Barbáchano
Photographs:
Pedro Barbáchano
Click
on the images
to see them enlarged
In quality framing
you
can't go half way. This is the
back side of a drawing
fixed to an acid-free matt
with adhesive tape. The damage
done is irreversible.
Foxing
Another sample of the
careless use of inappropriate
adhesives, in this case
contact glue. The glue aged,
darkened and lost its
adherence, damaging the work of art irreversibly.
A work on paper badly
damaged by framing
and the materials used
Another case of foxing
Here we can see the
damage caused by light
(darkening of the image)
and by the matting.
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