(Reader’s question) I have a question for readers of the KSS website. Many, if not most, of the 1960’s souvenir sheets from South Korea have gum creases or folds that are especially prominent on the gum side of the sheets. With scans, you can see some of the folds on the face of the souvenir sheets.
See attachments for some examples of these gum sides. These creases can also be seen on the regular and commemoratives of that era, but seem to be more common on the souvenir sheets. Obviously these were caused somehow in the printing/gumming of these sheets. Does anyone have information on what caused these gum creases?
This would have been a great question for Lyman Hale…
Gum creases are very common especially on souvenir sheets of all countries (Portugal is even more common than South Korea). The larger the sheet the greater possibility of the creases. I believe that the creases are more from the printing stage than from handling, and of course the creases detract from the look and the value of the sheets, although they seem to be tolerated in the resale of the item.
First, I have no info specific to the korea situaion.
Also I dont know why s/s issued without gum should have gum creases, or paper creases.
As of s/s issued gummed, there is the gum&calender question.
Calenders are a system of three or more polished steel cylinders (can be heatened), where in-between coils of paper ec. are guided thru snake-wise under high pressure. The purpose is to produce high class surfaces which are very smooth and show brilliance. The high smoothness is required
(a) if the original paper does not have the surface smoothness required for for high grid (photo-) gravure printing;
(b) if gummed, unprinted paper for later stamp printing is slightly uneven due to the coiling tendency of old style gum. It then gets smoothened again by the calender systems, but the gum sometimes gets slightly broken which results in the calender- or gum creases. This is first with the gum, but sometimes also affects the design (ungummed) front side. This calendering of gummed sheets was a standard step in stamp production up to the 1950s. In most countries this ended when arabia gum was replaced from stamp gumming process ca. 1953/55. Other countries continued the usage of similiar gum which required calendering.
Update: the ROK s/s of the 1960s/70s are on very thin, low quality paper and in my experience about 80% have small creases, knicks ec. Also saw full s/s packages of 500 of same period where a large part already appeared unsuitable for a good quality when still beeing unmolested in the packages… So its also a paper quality problem.