Paper splitting

The paper splitting process is a system developed at the University of Jena in the 60s by the restorer Günter Müller method with the (eg by ink corrosion ) damaged paper can be restored. The paper-splitting method is used only in serious cases, as it consuming ( therefore expensive ), and the original is changed.

The procedure

This is to be restored sheet of paper is placed in a special bath, so that it swells and pollutants are washed out of the paper. Then the front and back are each provided with a glued behaftetem gelatin adhesive liner ( release paper ), wherein the pressing of the lining papers is done in a hydraulic press. The swelling of the sheet can this pull them apart, and cleaving to the paper in half. Now in between a thin, acid-free and buffered Japanese paper ( core sheet ) is glued under pressure and so the two original paper halves joined together again. Calcium carbonate in the Kernblattverklebung acts as a buffer against future emerging acids. In the last step, the lining papers are removed again in an immersion bath with enzymes to dissolve the gelatin Kleberes. The technological limitation of the method is to not always uniform splitting of original sheets, which lies in spite of careful and exact procedures in the great variety of countless papers. Each paper has, viewed over its cross-section, not a homogenous fiber structure and no uniform distribution of fillers. This internal structure is of great importance for the capillary and the gradiell distributed tensile properties in the blade cross-section. This applies to both handmade as well as machine-made papers in different specifics. Because of this inevitable and production-related property processors denote the two sides of a paper as recto and wire side. Consequently, these issues affect the technology of paper splitting process in a differentiated manner.

Alternatively, may be somewhat dampened the paper splitting process the lining papers, so that the moisture can penetrate into the work of art and it does not have to be placed in a bath.

History

• Cleavage of the paper already in 1901 published " Bookbinding and the care of Book " mentioned by Douglas Cockerell.
• This restoration method is known primarily for the conclusions drawn by ink corrosion affected handwritten sheet music of Johann Sebastian Bach.