We have been making gum prints since 1984. The last 10 years we have made
our gum solutions from lumps. Today a very odd thing happened. As we were
going to test a new supplier we made two different solutions. With the new
supplier everything went well but with the one that we have used before an
odd thing happened. When the gum lumps (from Sudan) were almost solved the
solution became very thick, like tough glue and even if we added more water
than we usually use it is still like snot and has now become more viscous.
Last two weeks we teached gum in a school. The gum lumps were in a bag in
the same room where we sized the papers and hardened them with glyoxal
(using glyoxal for the first time in our alt-photo life.) We had two paper
sizing sessions. The first time when we hardened the papers we noticed a
little irritation but far from the problems with formaldehyde. The second
time the students made it themselves and they were "complaining" over the
smell of the glyoxal, telling almost the same problems one gets from
formaldehyde.
Just before we went to this school we made one liter of gum solution,
tested it and it worked very good and also kept that way (no snot!) during
the first week. The last days during the course we made more solutions for
the students so they can continue themselves. The gum solution was tough
like glue!!! We could not find any answer there (rumours said that the
students had put too much glyoxal in the solution). But today, at home,
with the lumps that were left over from the teaching session the same thing
happened again!!!
Now we are wondering: What has happened? Has the glyoxal something to do
with it? Shall we throw away the lumps we still have?
Hope for help
Hans & Chia