Re: sodium perborate/ Carbonate / Tetraborate decahydrate VS. dry cleaning

[Jennifer Hein <jhein@xxxxxxxxxxxxx>]

To the general discussion about spot bleaching,
I am remined once again, why people do not openly discuss treatments as
I dislike being scolded by those in institutions.
Yes I am first an art major then a conservator, so that my chemistry is
slim.  That is why I appreciate this list with all of the chemist who
read this and help me out, Thanks.

I made the comment about a paste for spot bleaching because I have been
in the Midwest for over 10 years.   I left the more sheltered east
coast museum environment to work in a less supported area, re the
middle states anywhere between PA & CA.... ironically. I respond after
years of phone queries for a State Museum as the sole conservator for a
collection of 300, 000 cultural objects.
 I sometimes forget the readers of this list are not AIC members, but I
have always said do a 5, 15, 30 & 60 minute test... for any
treatment.   I am reminded I must type a disclaimer with any comment.

Many people will bring the object in question to a dry cleaners which
is far worse than the spot bleaching I had suggested. We had 6 weeks of
dry cleaning classes in NYC.
I was schooled in a technical program but have given up my
institutional sponsorship, since in the US it does not pay as well as
those European colleagues who respond to this list.

And yes I have even had superiors who are "museum" curators tell me I
must do "Whatever it takes" to get rid of the spots.  That is why I
eventually left... so don't feel bad if you are demanded to do the
same. They do not teach us how to deal with curators, well enough.

>Yes, I agree that " All the chemicals mentioned in the previous
postings are essentially
> oxidizing bleaches, meaning that a change (of colour and chemical
structure) is achieved on the textile fibre by further oxidizing
(damageing), in order to visually obtain a unstained textile. The other
bleaching option is reducing agents (like sodium borohydrate), which
transforms the brownish areas of plant fibres into colourless form and
subsequently can to be rinsed out,

 Bleaching is a process hardly ever (suggested to be) used anymore in
Textile Conservation. If so, reducing agents are a better choice after
 careful testing and preferably only on uncoloured areas on textiles.
(Best on white cotton grounds of tablecloths and bed covers)

I still stand by any spot cleaning that is possible to reduce the
overall wear of treating the entire object.

Note : OOPS  I mistakenly credited Betty Kirke with the spot paste our
chemistry teacher had suggested, which was Borax paste.

Betty had given us a recipe for sodium metasilicate, sodium hydroxide,
sodium bicarbonate (baking soda) hydrogen peroxide & H20.
PS CHEMISTS, How do all those ingredients translate??
Excuse me for any issues.
--Jennifer Hein
Preservation Consultant and
Historic Object Conservator of Textiles, Leather & Ethnography
PO Box 90379, Indianapolis, IN 46290
Toll free # 1-866-575-9296