Re: removal of oil and soot

[jscheer <jscheer@xxxxxxxxxx>]

Joanne Hackett's advice provides an excellent primer for the removal of
sooty, oily stains.  I would add that when considering dry-cleaning as an
option for textiles sturdy enough to withstand the process, one should
consider both the polarity and the aggressiveness of the solvent (generally
measured by its kb value). The dry cleaning industry has recently become
more interested in testing an array of new solvents - and machinery -
designed to replace the class of chlorinated organic solvents (particularly
perchloroethylene) that has dominated commercial use since before WW II.
Because the cost of new machinery is very expensive, however,  most
dry-cleaners will have access to only one of several commercially available
solvents.  Conservators interested in working with a dry-cleaner who is
interested in conservation cleaning should ask about the type of solvent
used and inquire about less aggressive alternatives for dry-cleaning
delicate and historic textiles when that methodology is called for.

Jonathan Scheer
J. Scheer & Co. conservation dry-cleaners

Joanne Hackett wrote:

> Generally speaking, the problem with smoke damaged textiles is that what
> we think of as soot is really only about 50% particulate matter, the
> rest of the soot is of an oily nature, especially so in the case of an
> electrical fire where the products of the fire include plastics etc.
> The approach to try when dealing with soot damaged objects is to start
> with particulate soot removal and then to move to solvent cleaning of
> the underlying 'oily' stains, and then on to wet-cleaning if necessary.
> In removing particulate soot the vacuum is the first tool of choice.
> Try to vacuum away as much of the loose soot as possible without
> touching the textile surface.  (Wherever the soot has been touched it
> tends to become more ingrained and bonded with the fabric below.)  Very
> oily soot may not respond well to vacuuming, but it's the best place to
> start.  I found that the soot damaged objects that I cleaned responded
> well to 'dry-chem' sponges, these are the vulcanized rubber sponges sold
> by many conservation supply houses and hardware stores.  Brands include
> 'Dirt Eraser' and 'Wonder Sponge'.  These sponges are used widely by
> commercial fire salvage companies for general clean up.  Tentative
> testing suggests that these sponges are harmless to sturdy textiles,
> especially if any possible residue is vacuumed away after treatment.
>     The underlying oily stains are probably best dealt with by
> dry-cleaning by a trusted and experienced dry-cleaner.  I found that the
> oily stains below the soot on smoke damaged cellulosic textiles
> responded well to a series of solvents starting with relatively
> non-polar solvents, moving to more polar solvents and finally
> wet-cleaning.  (Historic textiles may not be able to stand this amount
> of cleaning!)  The single Nylon object I treated did not respond well,
> and given the similarities in the structure of silk and Nylon, I suspect
> that silk will not respond well either.
>     One thing is certain, time is of the essence.  The soot will be much
> more difficult to remove the longer it is allowed to remain on the
> textiles.
>
>     Try the following articles:
>
>     Spafford, S.  and F.  Graham.  1993.  Fire Recovery at the
> Saskatchewan Museum of Natural History.  Part 1, Description of Events
> and Analysis of Recovery.  And, Part 2, Post-Disaster Cleanup and Soot
> Removal.  ICOM-CC postprints, Tenth Triennial Meeting, Washington DC.
>
>     Gray Armstrong, J. D.  et al.  1981.  A Furnace Puff-back:  The
> Unique Problem of Soot on Objects and Costumes.  AIC Preprints, Ninth
> Annual Meeting, Philadelphia, PA.
>
>     Hackett, J.  1998.  Observations on Soot Removal from Textiles.  The
> Textile Specialty Group Postprints Volume 8.  AIC Twenty-Sixth Annual
> Meeting, Arlington, VA.
>
> I hope this is helpful.
> Joanne Hackett
> Fine Arts Museums of San Francisco.