After reading this previous thread http://goscf.com/t/77255
about Davac gum I got interested in
the Canadian part of the story.
Here are the two Canadian issues with DAVAC gum
Scott/Unitrade 447 1966
Scott/Unitrade 453 1967
Below are the Post Office new issue announcements.
The Canada Post Office
Department announcement stated the reason for using DAVAC gum was that it had proven superior adhesive qualities
and it was tasteless
It was also virtually invisible compared to the dextrine gum which had a yellowish colour and was shiny plus it left a taste in your mouth.
When the second DAVAC gummed stamps were issued in 1967 the announcement stated it was "successfully tested"
So successful apparently that DAVAC gum was never used again on Canadian stamps after these two.
Both stamps were printed by Canadian Bank Note.
When British American Bank Note got the contract to print stamps again they tested DAVAC pregummed paper on their new Goebel press.
From The Goebel Press Era of Canadian Stamps
by Ken Sargent with Leopold Beaudet.
For the trials, we printed the "Baby Sister" labels in booklet format in various colours. We tested the capability of the press to print several colours from the one engraved cylinder. Our tests were done on pregummed paper with both Davac and dextrine gum. These trial printings were not considered to be security items. Although the bulk of the test runs were destroyed, samples in the various colours were retained for further study.
On subsequent tests, we found that Davac gummed paper presented a problem. Small particles of the dry gum detached onto the printing surface as the roll unwound. These particles prevented paper-ink contact in the gravure units so Davac gummed paper was never used on the Goebel press to print stamps.
By 1971 both CBN and BABN were using PVA gum for all their paper.
If I can remember anything about these stamps when they were issued 55 years ago I seem to recall that the general public didn't quite know what to make of it and were not too fond of this new type of gum.
People thought that there was no gum on the stamps
Some were wondering why doesn't this gum have any taste at all ?
No taste,no gum they figured.