Lead

David Kerr <d.kerr [at] nls__uk> writes

>...  A note has been inserted
>with the package of blocks indicating the metal may contain lead and
>therefore lead oxide may be present.  What precautions should we be
>taking when handling these blocks and are there any recommendations
>that should be followed should Library users wish to look at them.
>Also, the printing blocks haven't been cleaned since they were last
>used with a combination of dried ink and dust on them.  Does anybody
>have any recommendations for cleaning them.

Having a printing studio as well as a conservation studio, I can say
that it is most probable that if the blocks are pinned to a wooden
base, then they are not lead based, as most line blocks were and
still are made from zinc, magnesium or copper. Most of these blocks
were made by etching away the surface leaving the black part of the
image. If the block are cast in lead then it would be cast to type
height in a solid piece.

Safe handling of type and line blocks should include thorough
washing of hands after use. To clean blocks with dried ink deposits
you can use Hard ink remover supplied by Ultrachem (phone 0800
616000) which is basically Dichloromethane (harmful and should be
used in fume hood with Nitrile gloves) this will get rid of the most
stubborn ink deposits.


                                  ***
                  Conservation DistList Instance 18:25
                Distributed: Wednesday, December 1, 2004
                       Message Id: cdl-18-25-007
                                  ***