: Conserving Government Propaganda prints from the Great War

Welcome again!

We are in the final stretch of concluding this interesting and amazing project. We have been working hard during the last few weeks mounting and framing the 66 lithograph prints to have them ready for the exhibition The Great War: Britain’s Efforts and Ideals on the 2^nd August at National Museum Cardiff.

In the following video you will enjoy the framing process carried out by our colleague Richard. As you can see it is a delicate procedure and the framer needs to be really clean and gentile with the work of art.

We have had the 66 frames specially made and stained by a local frame maker. The scratch resistant Perspex* we have used had to be washed with soap and water to remove all traces of adhesive before being taped into the frame. Conservation framing is about making a sealed package to protect the work of art from the outside environment whilst making sure that the content of the package are all up to conservation standards.

Once the Perspex is fitted in the frame, we clean it very well with glass cleaner and anti-static cloth being sure that is completely clean and we don’t want to scratch the Perspex. Then we put the mount with the work which is already free of any fluff over the surface in the frame. After that, we put in the backboard and keep it all together using a framer’s gun. Lastly we seal the frame with gum brown paper tape.

Don’t forget to join us next Saturday 2^nd August for the opening of the show!

*Perspex: acrylic material is useful because it is light and unlikely to break on impact. However, these materials do scratch more easily and because of static, should never be used to glaze pastels, charcoal, chalks, or friable material

Now it is time to research the fibres used during the paper making process in the different papers of ‘Effort and Ideals’ lithograph prints.

There are several methods to identify fibres such as the staining technique. The most common is Hertzberg’s Reagent which is used for paper fibres are based on iodine and zinc chloride. This type of stain is formulated to dye different groups of fibres differing colours. However, there are many disadvantages using this system because the specific colours stated for particular fibres are difficult to reproduce.

So, in this case we decided to take some samples of fibres of the prints and identify them under the polarising microscope.

In the first image, we are taking a small sample of fibres from one of the prints. We are using an invasive and destructive technique for that reason we have to be extremely careful taking the sample. Just shaving a little bit the very bottom edge we will be able to get enough fibres to analyse in the microscope.

In the third picture we are leaving the fibre sample on the microscope slide. After that, we will cover the sample with a cover slip and sealing with Meltmount (is a thermoplastic: it is fluid when heated and functionally a solid at room temperature; the appearance of the prepared slide will remain unchanged after the slide is returned to room temperature).

Once the sample is ready, we will work with it in the microscope. We took photos applying different magnifications.

In the fifth image, you can observe a detail of a linen fibre through the microscope. The term ‘linen’ covers a wide variety of material described as flax or linen. In both Europe and China flax has been used as a textile material since at least 4,500 BC.

The raw material after cutting and removing the seed head is retted in still or slow running water to slow process of bacterial decomposition. In some areas the process is carried out in a damp atmosphere only.

Linen is a bast fiber. Flax fibers vary in length from about 25 to 150 mm (1 to 6 in) and average 12-16 micrometers in diameter. Flax fibers can usually be identified by their “nodes” which add to the flexibility and texture of the fabric.

Other samples taken from the thinner prints revealed cotton as a main material. So in both cases we are talking about good quality paper fibres.

Here we are again with more news about the lithograph prints conservation process. Now is time for mounting each print in its own conservation mount to be ready for the exhibition opening 2^nd August in gallery 18 at the National Museum Cardiff.

Preparing the mounts where the prints will be housed for the next 100 years hopefully! The mounts are cut to the museum standard size, using 100% cotton alkaline buffered museum board (the most expensive available – but the highest quality). The back board is hinged to the mount using water based adhesive tape.

In the following photos you will be able to see how I attach the print to the backing of the mount. First of all, we attached the hinge to the back of the print on the top edge. The hinge is made with Japanese tissue. (Second Photo)

Then, in third photo  I am applying an adhesive over the surface of the hinge. This then folds back over and stick to the back board of the mount.

To reinforce the hinge we will glue another hinge over the top, creating a T hinge. This then allows the print to hang within the mount.

After one week making mounts for the prints we have already done 30 mounts.

Another 36 more to do and just 7 weeks to go… But we still need to make the frames and put them in…

Do you want to know what happened after washing one of the lithograph prints??

So here you are, the before and after washing treatment where you can see that the foxing spots have disappeared completely over the paper surface.

As we said before, the foxing reddish-brown spots can appear in the paper surface due to different causes. For example, the print has been exposed to relative humidity and temperature fluctuations for a long period of time creating an environment for the growing of mould or another possibility, could be that during the paper making process were used raw materials infested with mould.

These micro-organisms can remain latent for months or years awaiting for the appropriate conditions for growth and there are a wide range of colour stains. In some of the lithograph prints we found basically small yellow spots in different areas of the paper surface.

Hello again!

This week we are going to talk about the watermark found on the lithograph prints.

Do you know what a watermark is? Well, the watermark is a design or a pattern which is made during the paper production by the paper makers. The first paper mill which introduced a watermark in its papers was Fabriano, Italy in 1282. A watermark is made by attaching wire in a shape or letters to the mould, the sieve which catches the fibres making a sheet of paper. This then causes the paper to be thinner in this areas. Another way to make a watermark is impressing a water-coated metal stamp or dandy roll onto the paper during manufacturing. Watermarks can show us the manufacturer’s name, an animal, geometric designs, etc.

If you hold a bank note against the light you will be able to see a watermark!

During the lithograph prints conservation process we found in many thinner papers a Holbein watermark. After some research, we discovered that Holbein paper was a handmade printing paper sold by Spalding & Hodge, 145-7 Drury Lane, London WC. At the end of nineteenth century Spalding & Hodge were the owners of paper mills at East Malling in Kent also they bought Horton Kirby Mill, South Darenth, Kent in 1872.