At 01:02 PM 10/5/1998 GMT, you wrote:
>Does anyone had problems with silk conservation ?
>The fact is that some silks get broked after some years while other qualities
>remain fine with no problems. I wonder if it is simply low quality or the
silk
>or is from colouring materials used on it ?
>Apparently fibres gets too dry and starts collapsing easily.
>Is there any "treatment" to be done before it starts breaking ?
>
>Thanks for the attention
>
>Emanuel
>

Emanuel,

Everyone has problems with silk conservation.  As Hodcarry mentioned, the
dyes and mordants (solutions used to fix colors) often caused long term
problems with silk, and, although less frequently, with cotton.  Silk,
however, has some unique sources of degradation.

Silk quilts of the 1820's and 30's usually seem to be in better condition
than those of the later 1880's and 1890's. In order to stiffen the silk and
give it a a more substantial "hand", manufacturers of clothing would soak
the cloth in solutions of metal salts.  When dry the silk would hold the
billowy shapes desired at the time.  It also made the silk heavier.  This
became an important factor when the enormously popular fad for Crazy Quilts
started in 1884.

For the next ten years there were so many crazy quilts being made that the
traditional source of fabric for quilts, old but not worn out dresses and
suits, could not come close to satisfying the demand.  Clothing
manufacturers and cloth sellers stepped into the breech by supplying bags
of scrap silk sold by the pound.  Anything that would add to the weight of
the silk would add to the profits of the merchants and less scupulous
purveyers even added iron filings  from the machine shop next door.

Over the next hundred years the protein in the silk contributed electrons
to the slow oxidation reactions which changed the chemical and physical
properties of the fibers.  As a result the silk threads became brittle and
lost their tensile strength.  The process did not affect all silk fibers
consistantly: often the warp of the cloth is gone but the woof remains as a
feathery ghost of the original fabric.

The first "treatment" is to avoid bending or rubbing any of the aflicted
silk.  A fine nylon netting is often sewn over deteriorated pieces to hold
them in place and limit further movement.  I do not know if there is a way
to remove the inherent vice of the chemical additives without severely
damaging the silk.  If anyone on the list knows how to do it, I would love
to hear about it.

David Hupert