Tony the Billigs booklets are nearly as old as
your good self, so one can presume they are results
of roneoed multiple sheets used for brevity.
J&K just poked their nose in (although I didn't pick that)
I cannot see you taking on TRAVANCORE, but it would be warmly welcomed if you did, to add class to the thread,
and no doubt would be followed by many Trav- "encores"
I think for your ink query, it is extremely difficult to ascertain, one can only go on the result, then work backwards to the probable cause, especially where pigments are concerned.
You are quite correct in your assumption of the ink recipe however
Letterpress, collotype and lithography use "paste" inks in their process, pigment based systems using drying oil similar to linseed as a binding agent,(vehicle) with other additives including dyes.
Whilst the following may not be entirely pertinent, I'll post it as it is fascinating reading regarding the associated problems using certain inks, if not on the stamp itself but the printing plate.
February, 1993
SOME PRACTICAL CHEMISTRY
by Max Hooper
In the early days of postage stamp production, a favorite pigment was vermilion,
which consists of mercuric sulphide. It was valued because of its strong red colour
which did not fade.
But mercury compounds react with copper, as most of us were taught in chemistry
lessons at school. I can remember naughty boys who placed a halfpenny in a solution
of a mercury compound. Soon it would be coated with a mercury alloy and would
look like a shilling.
Perhaps printers in the nineteenth century were not taught chemistry, because some of
them had to learn the hard way.
Basset Hull's book tells us on pages 47 and 99 that vermilion was one of the
ingredients of the Id Sydney Views. It is not surprising that the copper plates had a
short life.
Later, the printers switched to steel plates, but on age 231, we again read of copper
plate (for the De La Rue 1d) being destroyed by vermilion.
De La Rue had the same problems with the Great Britain 4d in 1861. ( See page 20 of
Easton's history.) They ended up coating the plate with silver. They later did the same
with some other plates, and charged extra for it.
In 1879, Queensland began using copper plates. Most of their Id reds were coloured
orange or yellow, and some of the plates wore out quickly, until in 1896 they finally
learned to coat them with nickel .
Our early stamp printers had other chemical problems. Basset Hull tells us that
ultramarine was one of the ingredients of the 2d blue Sydney Views. Ultramarine is a
mineral which contains colloidal sulphur, and this also reacts with copper. No wonder
the plates didn't last.
The inks also used flake white, or basic lead carbonate. This reacts with the sulphur in
ultramarine {and also with vermilion) to produce black lead sulphide. This may not
have worried the printers who expected the stamps to be used up quickly, but it should
worry collectors. A lot of 2d Sydney view stamps now look grey rather than blue,
We may also spare a thought for the health of the early printers. Recess printing
required the printer to wipe the surface of the plate free of ink each time a sheet was
printed. Now vermilion and flake white are poisonous. How much of these ingredients
would have stayed on their hands? What hope was there of cleaning their hands before
eating?
A.F.Basset Hull: The postage stamps, envelopes, wrappers, postcards and telegraph
stamps of New South Wales (1911)
J. Easton: The De La Rue History of British and Foreign postage stamps 1855 to
1901.
Posted 05/07/2010 04:01 am
, I should be thoroughly spanked for using the word. It's just that 'sulphurization' seems a little excessive.)
