Cellulose is explosive, literally. If an open flame touches a keytop the
entire set of keys will flash burn, charring everything around it, including
the keytops, making them very difficult to recover.
I would replace the set ASAP.
Using dark stain you can stain the white tops to match the old color. There is
a product available from the supply houses for this purpose, look in the area
of the key materials.
Please remember that cellulose is next of kin to gun powder.
Have a happy new year.
Newton
nhunt@rci.rutgers.edu
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