CCI2014050714

-20-

The pil of the leather before treatment was 4,2 whIch is within the desired rangę.

After treatment the pH was 5,8 including 2% of buffering materiał. The iron and copper content were determined by means of atomie absorption spectrometry resulting in a percentage of 1,2 for iron and 0,007 for copper.

After treatment these percentages were gone down to 0,09% for iron and 0,004% for copper.

The oil used in the previous step was next removed with hexane. The object saturated with the oil was immersed in a bath, which was changed several times.

This treatment was continued for about 3 hours, until the bath liquor no longer madę one's fingers greasy. To ascer-tain that the oil had in fact been removed, the fat content of the object was determined.

After drying of the object, which took very little time, a dressing was applied to bring the fat content of the leather to 5%. This was done with a solution of 2 g of lanolin and 3 g of neafs-foot oil in 95 g good ąuality spirit free from any aromatic compounds. The dressing was applied in a single treatment. The oil was allowed to penetrate into the leather and the surface rubbed to remove the excess.

The restoration

We madę first a complete copy of the jerkin in new leather, following the drawing mentioned above.

Some modifications were necessary in order to get the shape right, to accomodate irregularities in the original.

From this copy we were able to determine exactly the shapes and size of the missing pieces; to make fills and replace-ments for the missing right sleave and back skirt.

For the fills and restorations we first treated new calf with Imidazol and then dyed the leather using the Stahl system. We dyed both sides, the flesh side with a spray and the grain side by hand.

The Imidazol pre-treatment madę the dyed leather color-fast, by preventing a drop in pH when the leather was exposed to daylight.

It is the changes in pH of the leather and not a change in the dye itself, that causes the color to change in dyed Leathers exposed to sunlight.

With the dyed leathoi w<‘ mp.il md first the tears, holes and weakened parts o! the origlnal. Por the tears and weak parts, we used very thin skived leather. When we filled holes we did not skive the origlnal, only the new leather. The new parts were attached with Mowilith polyvinyl acetate emulsion. When all the missing parts were filled in, we used a smali soldering iron to burn in the decorations on the new leather, and to integrate the fills with the original. When this was finished, finally we sewed all the pieces together using the original holes and the original stitching method, by means of the saddler maker's stitch.

Products used:

Oakite 131. (Rust Remover).

Castor oil.

Lanolin.

Neat's-Foot Oil.

White spirit.

Imidazol.

Polyyinyl acetate (Mowilith).

Jerkin from the 16th century