Polymers on cloth and shoes

Ingrid Neuman <berkart [at] earthlink__net> writes

>We have a Gianni Versace red sheath dress which is composed of 51%
>silk, 46% acetate and 3% polyurethane.  The top layer, the
>polyurethane, is cracking at this point on one shoulder although the
>dress has never been worn and has barely seen the light of day.  It
>is curious that only one of the top seams is deteriorating.  Does
>anyone else have any experience with this type of cloth from the
>1990's?  Can anyone point me in the direction of some written
>reference material regarding this polyurethane coating?

In the second half of the 1960s, furniture design, in particular in
Italy, increasingly started to utilize plastics. In particular
polyurethane, which could be produced in different modifications,
started its successful career in industrial appliance. Textile
carrier substrates coated with polyurethane are typical of this era.

Towards the end of the 1960s, new processing technologies and
products enabled the manufacture of micrometer-thin
polyester-polyurethane coatings for elastic fibers, knitwear and
non-woven fabrics made of artificial fibers. Their characteristics
led these textiles to be called "wet-look" or "crinkled patent". As
a result of the extreme thinness of the coatings and the sharp
decrease in hydrolytic stability with age, within just a few years,
these products became less resistant to cracks and their adhesive
qualities were greatly reduced. The degradation lead to such
phenomena as discoloring, brittleness, cracking, and detachment of
the coating.

The deteriorated material is highly susceptible to mechanical
stress. A possible way to consolidate these kind of coatings is the
treatment with a watery, fine dispersive anionic polyurethane
dispersion from Bayer AG called Isovin V. The consolidation
treatment was carried out in defined areas of a damaged cover of a
design chair 6 years ago. Till now the coating is stable and without
any undesirable aesthetic or mechanical change.

In 2002 I graduated with the diploma thesis on "Polyurethane in
1960's furniture design" with a special focus on polyurethane coated
textiles. This work is in part published in:

    Cordelia Rogerson
    "Garside Paul: The future of the 20th century"
    postprints from the AHRC Research Centre for Textile
    Conservation and Textile Studies
    2nd annual conference 26-28 July 2005.

If you do have special interests in degradation and consolidation of
flaking polyurethane coatings please don't hesitate to contact me.

Tim Bechthold (Dipl.Rest.Univ.)
Head of Conservation Department
Die Neue Sammlung
Staatliches Museum fur angewandte Kunst
Design in der Pinakothek der Moderne
Turkenstr. 15 - D
80333 Munchen
+49 89 27 27 25 0
Fax: +49 89 27 27 25 561


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                  Conservation DistList Instance 21:61
                  Distributed: Saturday, May 17, 2008
                       Message Id: cdl-21-61-004
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