Schwan-Stabilo marking pencils

Karin von Lerber <karin.vonlerber<-at->prevart<.>ch> writes

>Helen Privett <hprivett<-at->museum<.>vic<.>gov<.>au> writes
>
>>One of our collection managers has recently proposed using
>>Schwan-Stabilo Marking Pencils for use on plastic objects.  I wonder
>>whether anyone has experience with using these pencils for this
>>purpose and if they'd like to share their thoughts?
>
>I am not sure, if a permanent marker is what you want to use
>directly on plastic objects. But if you decide to do so: I tested
>several permanent markers back in 1999. Stabilo was not the worst,
>but also not the best.

The other concern with plastics is not just the permanence of the
ink, but also the solvents, the binding media, and the hardness of
marking tip.

Many plastics are soft enough that even felt tip markers can leave
visible scratches.

Many plastics have some degree of solubility in the kinds of
solvents found in markers. One the other hand, if the plastic is
completely insoluble to the inks and binders, plasticiser migration
can make it easy for the markings to be wiped off. Many adhesives
won't stick to plastic for such reasons.

You also have to be careful that the inks contain no dyes, as the
plasticisers and solvents can cause the dyes to bleed into the
plastic and become non-reversible.

Whatever system you try, I'd recommend getting samples of the types
of plastics you want to mark and test them to see: does the marker
scratch this plastic? Does the ink wipe off too easily when dry?
Does the ink migrate into the plastic with ageing?

If the plastics are not affected by ethanol I might try testing B72
in ethanol to adhere small paper labels (printed on archival paper
in carbon based ink). There you'd be testing to see if the adhesive
actually bonded the label to the plastic without the solvent
affecting the plastic (it's essentially the same problem: getting
something to stick to plastic without dissolving the plastic, but
you don't have to worry about any scratching this way).

I haven't researched this topic thoroughly, but these are just some
random thoughts on the topic.

Valerie Tomlinson
Conservator
Auckland War Memorial Museum
Tamaki Paenga Hira
The Domain, Private Bag 92018
Victoria Street West
Auckland 1142
New Zealand
+64 9 306 7070 ext 7304


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                  Conservation DistList Instance 27:18
                Distributed: Thursday, October 24, 2013
                       Message Id: cdl-27-18-002
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