Professional Art Conservation
Our conservation team can restore nearly any work of art
About our Services
Joel Oppenheimer, Inc., a nationally renowned art facility, was founded in 1969 by the conservator for the Department of Prints and Drawings of the Art Institute of Chicago to fulfill a need for professional conservation services in the private sector. We maintain an apprenticeship program and train our own staff, all of whom hold degrees in fine art and art history. Our staff can analyze and perform corrective treatments for anything on paper or canvas. This includes drawings, prints, maps, photographs, documents, paintings and Asian screens. Our laboratories have developed and perfected techniques for restoration of paper, canvas and photographs that enable us to retain delicate pigments, signatures and hand coloring.
With our expertise in both art and science, Joel Oppenheimer, Inc. employs the attention to detail of old world craftsmanship while utilizing state-of-the-art technology. Each piece and problem is treated with singular care. Our clients include major museums that require our particular expertise, smaller museums that do not have their own conservation facilities, galleries, institutions and private collectors nationwide.
Conservation and Restoration
Art conservation and restoration involves the preservation of works of art, arresting progressive deterioration that causes damage, and correcting damage that has previously occurred. Fine art restoration is divided into specific areas of expertise. Restoring a painting, photograph or drawing, for instance, is in essence solving a problem related to the substrate, or material on which the piece is executed, as well as the medium or emulsion layer that is applied to that substrate.
What is the Difference between Conservation and Restoration?
In art conservation, the objective is to arrest any progressive deterioration that is occurring so that the piece in question will remain intact, as it is, for as long as possible given what we know today. An example of conservation would be mending a tear using mulberry tissue and a neutral-pH, starch-based adhesive to prevent the tear from enlarging due to the natural expansion and contraction that occurs from variations in temperature and humidity levels in a sheet of paper. Another example of conservation would be deacidification, a chemical stabilization process. Restoration involves a cosmetic treatment that is intended to return the object to its original appearance, while retaining any patina of age that is considered an attribute. For instance, if a tear has progressed in a manner that detracts from the composition of the piece, we can graft new paper fibers into the tear, rendering it nearly invisible, thus restoring the object. An example of painting restoration would be replacing pigment losses to match the original as closely as possible. Restoration of a photograph may include a chemical bleaching and redevelopment process, as well as simulating a new emulsion surface.
What causes damage to works of art and how can they be properly conserved or restored?
The causes of damage to works on paper, paintings and photographs may often be the same, but the resulting problems can vary due to the relationship between the pigment layer and the substrate, and when present, the ground layer. Many of these conditions that threaten preservation or cause deterioration are not obvious.
To uncover a few of the hidden enemies of family heirlooms and works of art of all mediums one has only to look around their home. Each of us is familiar with one or more of these detrimental circumstances: pictures stored in a hot, dry attic, or in a basement with its inherent dampness; improperly framed pictures; family photographs mounted in acidic albums with damaging adhesives; heirloom letters and documents, folded, torn and stained from exposure to moisture, relegated to a dresser drawer.
When properly made and cared for paper, canvas or linen can last for centuries. However, they are extremely vulnerable to damage caused by improper storage and environmental factors.
Humidity: Exposure to excessive humidity can allow mold to form. Mold forms when humidity levels are sustained above 70%. Appropriate air conditioning or dehumidification will help prevent the formation of mold. Foxing, a brownish speckling that is caused by the chemical action of mold on colorless iron salts present in most paper, is an obvious sign of mold. The mold not only discolors the paper, but also feeds on sizing and paper fibers, thereby weakening the molecular structure of the sheet. Also, mold can penetrate the pigment layer of a painting and feed on the sizing in the canvas from the verso.
Moisture: Since most materials expand with moisture, a severe waviness or rolling of paper, called cockling, may occur when it is exposed to excessive humidity or moisture. When cockling is severe or mold is observed, the piece should be given to a conservator for flattening and thymolization, an anti-fungus vapor treatment. Trapped moisture between varnish and pigment layers of a painting can result in blooming, a whitish-gray film, and greatly reduce the aesthetic quality of a piece.
Light: Ultraviolet light causes fading, yellowing and embrittlement. It also greatly accelerates the effects of an acidic content. Fluorescent and sun light are the most harmful. Care should be taken where a piece is placed so that direct natural light is avoided. Ask your framer about using ultraviolet filtering glass or Plexiglas to limit exposure to ultraviolet light. While opaque pigments in paintings are less susceptible to fading, transparent glazes and varnish layers may be affected by ultraviolet exposure.
Heat: High temperatures accelerate deterioration of paper and embrittlement of paint layers. Works of art should not be stored or exhibited near a heat source. Heat also accelerates the damaging effects of an acidic content.
Air Pollution: Pollutants in the atmosphere can cause discoloration, embrittlement and eventual disintegration of paper fibers. More commonly, however, solid matter (dust and soot) present in the air will penetrate the paper’s surface or accumulate on a paint surface.
Insects: Silverfish, termites and wood worms can cause considerable damage to paper and canvas.
Varnish: Older paintings, and many modern ones are coated with natural resin varnishes as a protective layer. While the varnish served a purpose, the resin darkens with age and exposure, sometimes significantly altering and obscuring the appearance of the original work.
Acid: The Enemy Inside Paper
Certain elements that cause damage are inherent in paper. Consequently, dangers may come from within. Early papers were produced primarily from pulp made of rag (cotton fiber). It wasn’t until the latter half of the nineteenth century that wood-pulp fibers were introduced to commercially produced papers. Lignin, a natural element which bonds the cellular structure in a living tree, becomes an unstable component in ground or emulsified wood pulp, causing an acidic reaction.
Envision the strands of paper fibers as links in a chain. Acidic paper loses its strength and the links begin to break down. It becomes brittle and unable to support itself. In addition, wood-pulp paper fibers are short, producing a weaker sheet. Alum-rosin sizing, sometimes added during the paper making process, also is an acid producer. All acidic paper eventually will deteriorate if untreated.
Use of acid-free (100% rag) paper by publishers and artists is part of the solution. Collectors also should ensure that acid-free mats and papers are used in framing their pictures. If you have an object or collectible made of acidic paper, such as baseball cards, the deterioration usually can be arrested or significantly reduced by the conservation process of deacidification. Also, when paintings are framed to the edge in a wooden frame, the rabbet of the frame that is in contact with the canvas should be lined with an acid-free barrier.
What kinds of problems can be rectified and how successful can treatments be?
At times, our conservation lab parallels a hospital emergency room. We treat pictures that have suffered everything from floods to bullet holes. The problems we encounter and the dramatic results we can achieve are often impressive.
Embrittled paper can be re-hydrated and supported with special tissues.
Fragmenting and tears can be effectively repaired.
Stains resulting from water, pressure-sensitive tapes, glues, mold or mildew (foxing) and rust can be eradicated or significantly reduced.
Pieces that have been improperly mounted or glued down to boards can usually be removed from mounts and all glue residue eliminated.
Pigments that are cupping or flaking off can be consolidated and stabilized.
Varnish, lacquers and shellac can be removed from most surfaces.
Folds can be reversed or significantly reduced with controlled humidification and drying procedures.
Cockling or waviness from exposure to excessive water or humidity can be reversed.
Severely deteriorated canvases can be relined adding support to the canvas and pigment layer.
Trimmed canvases can be strip lined making it possible properly re-stretch them.
Torn or punctured paintings can be “rewoven” and pigment losses can be replaced.
The anticipated results are discussed with the client before proceeding with any treatment. Our vast experience with works of art and family heirlooms allows us to accurately predict the degree of success we can achieve. For additional assurance, we frequently secure permission to test a piece before proceeding with any work.
Tips for Handling Works of Art
Always use clean hands to handle books and pictures.
When lifting a matted or unmatted picture, use two hands to prevent bending, creasing or tearing.
Unmatted pictures should never be stacked directly on top of each other, but should be separated by a smooth, acid-free interleaf.
Never use pressure-sensitive tapes, cellophane tape, masking tape, rubber cement, synthetic glues, or heat-sealing mounting tissues on any picture that is to be preserved. A starch-based adhesive is best. It is non-acidic, non-yellowing, and easily reversed.
Paper should be stored flat, never rolled. Stretched canvases should be stored vertically.
Cleaning agents should never be sprayed directly onto the glazing material of a framed print or painting. The liquid can seep into the rabbet of the frame causing moisture damage.
Our Philosophy Rests on the Basic Principles of Art Conservation
The Principle of Discretion
The first task after examination is to decide whether the object will benefit from active treatment. A vast majority of cases do warrant treatment. There are instances, however, when a passive treatment such as proper archival storage or limiting exposure to ultraviolet light, is the only recommended solution. It is important for a conservator to know when to proceed, and to advise their client accordingly.
The Principle of Original Integrity and Allegiance
A conservator’s primary allegiance is to the integrity of the object or work of art and its preservation. An object should not be “over restored”. The artist’s intent, when applicable, should be respected.
The Principle of Reversibility
Technology will change and the knowledge base will undoubtedly grow, therefore all materials and techniques used in the restoration process should be reversible. A future conservator should be able to undo anything that is done today so that the object may benefit from any advancement in the field.