Preservation: Paper Conservation

Tools of the trade

Unrolling and documenting

A Technician documents an items to be exhibited.

One of the first jobs a conservator has to do once they receive an artifact is to document its current state.  It isn't unusual to spend the entire day going through the pieces delivered for documentation purposes. This is also a really nice way to familiarise myself with the objects prior to taking them to the conservation lab.

There could be as many as 30 pieces to go through and document these in one day! Prior to starting to unroll the objects, it is essential to make sure there is table space large enough to do this in comfortably and that the surfaces are thoroughly cleaned. The documentation requires cross-referencing the numbering system created by the collection owners to make sure that the pieces are named properly. Then measure and date (where known) them, after which each of the items are examined carefully to document any issues with the paper and/or the inks and other media used in them.

example of a part of a documentation sheet (work in progress).

Diagrams and photography are also used support these notes. This is to make sure the condition of each individual object is documented thoroughly before any conservation and framing takes place. It is also important to document both the recto and verso of the piece.



There can be conditions on how much conservation actually takes place. These conditions can be dictated by owners of collections and even by the piece itself. As an example an object that has lived its life being folded, the folds become a part of its history. They might need to be strengthened by adding support to prevent any damage and tearing happening in the future but flattening the object entirely may not be the best treatment for it. Just as with surface cleaning pieces with pencil marks on them, great care needs to go into the planning of conservation treatments, which also emphasises the importance of thorough documentation.

selection of tools used in paper conservation.

The tools that a paper conservator needs to do their job are numerous but at the very top of that list should be patience. All of the physical tools required are the trade-off for the patience as a conservator gets to work with fairly random things at times. Conservators need to stay inventive; dentists tools become irreplaceable and making small saw-blades into scraping tools or suddenly possessing a vast collection of small jam jars that fill up your toolbox is not unheard of.



The conservator has to remember that the job isn't always a rush of repair work. Not only does everything generally take a long time, the paperwork and other forms of documentation - sketches, maps and photography - are absolutely essential to the conservation process. But more usually you need to research what it is you are working on to gain an understanding to any issues related to it. This is not unlike the museum sector, where knowing the history of 'the stuff' enables you to treat it with sensitivity to the traditions of another culture or religion, for example. Of course the variety of areas in which to specialise in within the conservation umbrella are numerous - many similar issues surrounding paper conservation.

selection of tools used in paper conservation.

The significant difference between conservation issues in archives and museums are that archive materials are generally handled, and the ability to do so becomes a part of the research process. Yet museum objects are there to be looked at and admired, most of the time behind a glass and out of reach.



A conservator doesn't only need to know what to do with the vast selection of tools of the trade, but I think also needs to be part artist, part photographer, part chemist and part researcher - and have the patience of a saint.

Detail from a poster

When there is the proposed of an exhibition of some work, an conservator has the opportunity to visit the archive and have a look through some of the materials which may be used. The majority of the objects are hopefully in great condition. Usually a lot of the work has been 'spared' by the fact that items have been stored correctly, say posters are rolled up in tubes and not handled much in the past and has also been very well looked after by the holders of the collection.



At first assessment, the rolled up pieces propose an issue for not only any conservation work, but also for mounting and framing for the exhibition. Most of the pieces that are currently of interest for the exhibition planning team will usually need conservation treatments such as surface cleaning, some possible aqueous washing, certainly flattening and even minor repairs to be done. There are also issues to consider in regards to storage post-exhibition, as once flattened it would be best the chosen objects stayed that way. However, more often than not, a lack of storage space dictates the terms.



To figure out the best way forward with a collection's conservation processes, the holders usually deliver a 'sample poster' to work on. The purpose of this is to not only try and estimate the time for conservation needs for budgetary reasons, but to also test out a possibility of using facsimiles in the exhibition to spare some of the more delicate originals the exposure. This suggestion is often made in cases when an exhibition is to tour other venues after the Local Gallery.



Prior to getting the poster delivered, you would about the options for flattening processes and the large dimensions of any objects would also have to be taken into careful consideration when handling. The inks used on the 'sample poster' needed to be tested for fugitivity if any aqueous flattening methods were to be used. Fugitivity testing is required to determine if the inks on a piece of work are likely to run when in contact with water and is essential before deciding on any aqueous treatments. This testing is done by using a small brush dipped in water and wetting a very small spot on a piece of work, letting the water seep into the paper and pressing a piece of blotter on top to see if there is any ink transferral. The process of wetting a spot is usually repeated a few times to make sure the paper fibres have taken the water in sufficiently enough for the ink fugitivity test to be conclusive. Usually all colours also need to be tested separately, as two inks won't necessarily behave in a similar manner when wet.



Anytime any actual conservation takes place, a pre-conservation record is filled. In this, the most common points that are recorded are type of paper (machine or hand made, laid or wove), dimensions, gsm (the weight of the paper), tears, dirt, folds, holes, print type and other materials used on it. The item is also measured, sketched and photographed.



After this one begins the conservation of the poster.  The item comes rolled up and has not been seen prior to unrolling it at the conservation studios, and you can imagine the joy in seeing all these beautiful bright colours! Thankfully the poster itself was in very good condition - only the obvious flattening issues and minor surface dirt on both recto and verso of the piece.

corner prior to surface- and spot-cleaning.

Along one edge there were also areas of ingrained stains, where the dirt had embedded itself into the paper fibres. Since this poster was acting as the 'test piece', after a general surface cleaning with grated Mars Staedler rubber, an attempt is made to removing these stains.

corner after surface- and spot-cleaning.

With these stains only cold distilled water is used, a thin brush to wet the affected area and the capillary action of blotter with pressure from a bone folder to reduce the stain. Most of the stains along the edge were water soluble. The general misconception about washing items is that after washing the stains will have disappeared entirely. More often than not, this is not the case. Conservation is still a relatively young profession and in the past, bleaching has been used as a conservation treatment - thankfully these days this is not considered good practice.

Spot-cleaning an area of the stained edge of a poster, on this strip of blotter you can see the gradual process of the stain being lifted off.

After some satisfaction with the stain removal, it is decided that the paper and inks used were strong and stable for dry heat pressing to flatten it. This meant there was no need to wet the object but instead after placing it under silicone pieces, it was flattened in quarter sections under a heated press.

Mechanical surface cleaning

There are good reasons for mechanical surface cleaning. All of the Archive objects might not necessarily need a lot of work doing to them, but they will all need to be surface cleaned prior to framing, for example.



Surface cleaning materials is a very important first step in the chain of events that stabilise an item being conserved. Dirt on objects can be a source of deterioration and in worse cases can contain mould spores that flourish on nutrients found within the paper and any debris left on it. Water has a strong capillary ability and when paper gets wet, the fibres expand. They contract again when drying, and if surface cleaning hasn't been done, this action traps in any dirt or dust particles left on the paper.



Considering the safety of an object needs to be taken into account. The strength of the paper will determine how and if surface cleaning can be carried out. It is important to remember and know that pencil marks, cataloguing marks and random smudges on objects can play a historic part in the object's life and removing these marks will change the object drastically. I should also note that both recto and verso of the item need to be cleaned.



For the most fragile pieces, surface cleaning might take place by using only a brush - the size of the brush will be dependent on how fragile the paper in question is. Mechanical cleaning can also be done with the aid of chemical sponges, which are widely used in conservation. They are composed of rubber and are heavily filled with calcium carbonate and do not leave any residue on the paper's surface, but are very effective in picking up dirt.

example of how much dirt can be lifted off a print with a chemical sponge.

Rubbers are also commonly used, and the most widely used are Staedler Mars rubbers. This particular make is used for the same reason as the chemical sponges - research has shown that this rubber does not leave any residue on the paper's surface. On sturdier archival pieces, the rubber can be used as a block. For more delicate pieces and items with pencil marks, the rubber is grated and a piece of cotton wool is parcelled inside a piece of anti-static cloth and this is used to gently roll over the grated rubber, removing surface dirt as you go along.



Groomstick is another tacky substance that can be used when wanting to pick up larger bits of debris on an item - for example pieces of glass from a broken frame. Groomstick has a very tacky nature and is not recommended to be used directly on the paper as it can damage the fibres. Using a museum vacuum is also an option and is generally used with archives that are very dirty, for example objects that have not previously been stored correctly. Vacuums should have a filter at the tip to enable picking up any loose pieces that may come off in the process.



Cleaning any tears and around holes and other damaged areas can also propose a problem, as it is important to take care not to damage the object any further. For tears along edges of a piece, a piece of melinex can be used to slide into the tear - this way both sides of the tear can be gently cleaned with less risk of extending the tear.



Surface cleaning objects takes a considerable amount of time - especially cleaning larger pieces.



This worked wonderfully well and the final result is pleasing. A melinex sleeve was then made to size and the poster is being transported back to base for the next step in the process.

Digitisation

Now a days, more often than not, a conservator starts working at an Archives as a Digitisation Technician, since most Archives are constantly in the midst of a project.



But as they continue working in the Archives they will continue enhancing and refreshing their conservation skills by working with paper other Conservator Professionals, who have years of priceless experience in the field and have provided others with new challenges on a weekly basis.



Conservators are not generally involved with digitisation, but some have years of experience in digitisating archival materials, with a path to conservation fortunate enough to have the skills to both conserve an original archival object and to digitise it.  This is particularly important when there are only a handful of technicians in your Library/Archive/Museum.



The digitisation of materials is at the forefront for many collections, and plays a big part in not only extending the lives of materials by reducing handling but also by opening collections to wider audiences when a visit is not feasable - this is of course making a general assumption that access to the internet is available.



Increasingly many Archives have a long and successfull history in digitisation. Posters and larger materials that do not fit into most scanners so are photographed instead. To photograph large pieces, technicians use a photographic studio setup in a separate area. For acquiring the best possible results, we use a Mamiya RZ medium format camera with a digital Imacon back attached and a set of flashes for even lighting.



The issue with digital photography and scanning of materials is that despite the advances in digital equipment over the years, details can still get 'lost in translation'. With our 'sample poster', the issue became the finely detailed black ink images lined along one detail of the piece. The digital elements of the camera were not able to handle the thin black lines so close together and created a colour effect on the image that is not present in the original.

colour effect created where the digital camera wasn't able to properly register the fine black lines so close together.

The only way to get around this phenomenon was in the post-photography production of the image. By isolating the affected areas and adjusting colour casts and contrast in a 'photo editing application', to lessen the effect of the colour and bring the digitised version of the poster closer to what the original looks like.

colour effect controlled by digitally masking the area and adjusting contrast and colour casts.

Since the 'sample poster' was digitised with the goal of possibly creating a facsimile for the forthcoming exhibition, the file size, pixel count and focus needed extra attention. The plan is for the reproduction to be printed out the same size as the original. For optimising the results, this means that the pixel count needed to be high and the dimensions of the digital file the same as the original dimensions of the poster. Colour matching will also prove a challenge, as the way in which colours are represented are as numerous as there are computer screen calibrations in the world. For any final printing, the printers would ideally need access to the original to be able to match the facsimile colours as closely as possible with the original colours on the poster.

Facsimiles

original poster (left) with the two facsimiles.

There is a lot of debate about the use of facsimiles and replicas in the Library/Archive/Museum world.  But replicas have been used since the beginning and for good reason. Artefacts are replicated to allow for them to be displayed in multiple Museums around the world to give a much wider audience the opportunity to see 'the artefact' in the flesh.  Many people do not have the freedom to travel the globe to see a 'original'. The use of facsimiles can prevent both damage and loss of the original from events such as a natural disaster or theft.  There is even, now, the case of facsimile pyramid at Gaza designed to prevent further erosion and humidity damage from the millions of tourists they get each year.



For the facsimiles of documents, the digital master file is given to both the reprographics department and a local photographic printers. It has been very interesting to observe the differences between the two. The colour casts are subtly different and there appears to be a difference between the contrast settings. This is because neither department adjusted their settings prior to printing, so these differences will have occurred in the printing process. As the copies were made in the spirit of testing out the process, neither department had access to the colour and grayscale control patched photographs or original poster for reference so the colours were not as vibrant as on the original. There were also subtle differences between being able to see the pixels - one was a little bit softer compared to the other.



For the purposes of making a decision about whether to show facsimiles or not, we arranged for the copies to be magnetically hung on a wall for the collection owners to see what could be done. Although they were very impressed with the results, a decision has now been made in collaboration with the entire team that only originals will be exhibited.



The digital image can now also be used in the planned digital resource in support of the exhibition and shared online.