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.