Making Solvent Set Tissue

Today was the final lecture from our visiting tutor who has been teaching us board reattachment. For her final instalment, we looked at solvent set tissue, which is not completely dissimilar to gelatine set tissue, and can also cross over into the heat set tissue theme as well – a multifunctional tool!

The reasons for using solvent set tissue, are twofold, the first being to be used when a book has such sensative leather that to get any paste or anything containing water would cause darkening – this form of paper repair is completely water free and therefore at no threat of causing this. The second key use is speed, as once set up, the process can be much quicker than using paste and tissue. It does have its downfalls as well, which is why it might not be used all the time – it is more permanent than wheat starch paste, if it gets erectly onto the leather rather than the repair tissue, it cannot be removed.

So the technique is as follows:

  • Initially tone some tissue in preparation for it to be pasted onto
  • Get the equipment ready, including a squeegee, a small screen print tray and a water trough to cover them both once used – the adhesive is extremely quick to dry and will not come off once stuck.
  • Humidify the toned tissue.
  • Lay the frame onto a sheet of melinex – this is what the adhesive will end up on.
  • Paste out small batches of adhesive along one edge of the screen and squeegee evenly over the rest of the frame.
  • Once evenly spread, remove the frame and lay out the toned tissue, ensuring a flat surface.
  • Allow to dry.
  • This can then be stored for future use.
  • When using, reactivate with solvent.

The adhesive used is called Lascoux and is an Acrylic glue. It is of the same family as PVA, though unlike PVA, it is completely non-reversable once dried. It is possible to reactivate the adhesive with solvent once dried, though it will not remove it, just make it sticky again. It is this method that is used to reactivate the adhesive on the tissue when you want to use the tissue on a book.

Making Toned Tissue for Paper Repairs

Tissue toning is something I have only done briefly before this lecture, and not one I had had any instruction in. Having previously had a thorough introduction into pulp repairs with Alan Buchanan, this particular process of toning tissue seemed to make a lot more sense than perhaps it had done previously.

It was necessary to learn to and tone tissue in order to move ahead with our board attachment lectures. The use of japanese tissue is now essential in the repair of books and paper, and has more strength than one might imagine, indeed a hinge repair in japanese tissue is often enough to hold a board onto a book for the foreseeable future, though to look at it, it almost seems impossible.

20111122-162150.jpg

The technique for this tissue toning, was to create a colour pallet similar to the colours of the book cover in question. This was done using different acrylic colours, such as burnt umber and ocre, these can be mixed on a sheet of melinex as an artists pallet is. Once the desired colour is reached, the pigment is then dabbed onto the tissue using a damp piece of cotton wool. This means that it is possible to get a meddly of colours on the tissue.

Personally I was not so enamoured with this particular method. I found both the cotton wool and the tissue would soak up the pigment too quickly to get good coverage, and the tissue ended up looking too patchy and the fibres of the tissue would become damaged and fragile.

20111122-162202.jpg

An alternative method, which I personally prefer, is to make up a pallet of liquid colour in a relatively large quantity. Then the tissue is dipped into the liquid pigment. This way the colour is more consistent and will cover a larger area. It also does not put any strain on the tissue fibres, meaning they retain their strength. Once one tissue is toned, it is possible to add water to the pallet and get a lower percentage of pigment on another sheet, and so on until the pigment is gone and the tissue toning is quite pale.

20111122-162223.jpg

The negative is that it is important to get the right colour before you go ahead and tone the sheet, whereas in the former method, more colour can be added to get the toning correct. In both methods, colour can be added to the tissue once it has been added to the book to blend in the tissue. This is often done with black.

An alternative method, which I have yet to test, is using a spray gun to cover the tissue in the pigment. This should get a maximum coverage of pigment onto the tissue with a minimum effect or damage to the tissue.