Linda
Member 
Ex-mathematician turned visual artist and touring cyclist to bike across Canada, Europe, Japan etc.
Posts: 1,262 
What I collect: Mostly Canadian and European stamps about art / science / landscape
|
Post by Linda on Jul 20, 2022 11:07:24 GMT
This may be a weird and perhaps too artistically specific question, and answers surely depend on each country and different periods of time --
Does anyone know what kind of ink is usually used in cancels / postmarks? I don't mean the colour nor whether it's 'thick' or 'thin' (i.e. got stuck in the sorting machine easily or not), I mean more scientifically its chemical properties.
Is it usually oil-based or water-based? Pigment-based or dye-based? etc.
I have seen elsewhere saying that modern postage stamps are often tagged with fluorescent inks, but what about the traditional hand-stamped cancels? What type of ink is in the ink pad?
Since the marking has to be pretty archival-safe, I have always assumed it should be pigment-based, but I just saw on Google Image some cancels that faded terribly (I suppose that those covers were not constantly exposed under direct sunlight or something over all these years), so maybe I am wrong.
I didn't find satisfactory answers on internet, hence I am posting my question here.
|
|
philatelia
Member
Captain Jack - my best kiloware find ever!
Posts: 3,416
What I collect: Ireland, Japan, Scandy, USA, Venezuela, Vatican, Bermuda, Austria
|
Post by philatelia on Jul 20, 2022 13:28:19 GMT
This is quite a conundrum for those of us who have had mailers postmark permits. I tried several inks. That was almost 13 years ago and I’m trying to remember the different problems I encountered. A few were esthetic - they didn’t look like a postal cancel - too shiny for one. A few took too long to dry. A few were not truly indelible which is absolutely not acceptable. The best ink was the one that came with one of the stamping devices.
My recommendation, talk to whomever is currently marketing MPPs in the USA. Whatever ink they use will be your safest choice. Go to the MPP club website for info.
|
|
Beryllium Guy
Moderator 
Posts: 5,661 
What I collect: Worldwide Stamps 1840-1930
|
Post by Beryllium Guy on Jul 20, 2022 14:45:51 GMT
Thanks for your post, Linda. I am surprised to hear that a web search did not get you any good results, because when I did one for "postmark ink composition", I got the following: I imagine that this is correct for postmarks, because in the early days, the postmarks could be cleaned off the stamps by using solvents like acetone or benzene. Some philatelic writers, like Stevenson, have even suggested that hydrogen peroxide could be used to remove a postmark and leave the stamp intact. It was more often the stamps that were printed with the pigment-based inks, I think. At least it was the case with the Cape of Good Hope triangles from 1853-1864. Hope this helps a little.  |
|
Linda
Member
Ex-mathematician turned visual artist and touring cyclist to bike across Canada, Europe, Japan etc.
Posts: 1,262
What I collect: Mostly Canadian and European stamps about art / science / landscape
|
Post by Linda on Jul 20, 2022 14:52:29 GMT
Beryllium GuyWow, thank you for the answer. I didn't think to include the keyword 'composition' and only found information that I was not looking for. Some of them are too scientific -- talking about wavelength, which without specific device is hard to measure -- some of them simply aesthetic. Thank you again for enlightening me!
|
|
Beryllium Guy
Moderator
Posts: 5,661
What I collect: Worldwide Stamps 1840-1930
|
Post by Beryllium Guy on Jul 20, 2022 15:06:44 GMT
Linda, I am glad if I helped. In truth, I don't know that much in general about the inks used for postmarks and stamps, but I have learned a little in my study of the Cape Triangles. As it happens, the British Post Office was so concerned about fraudulent re-use of stamps by removing the cancels, that Perkins Bacon, original printers of the Penny Black and later the Cape Triangles, added a mineral ingredient to the stamp ink so that if the stamp was treated with a solvent like acetone, the design of the stamp would be affected. Interestingly, it was the adding of this ingredient (a derivative of prussiate of potash, which is a compound containing ferrocyanide), that turned the paper blue during the printing process of the stamps. That is why stamps from early GB, Cape of Good Hope, and others printed with these kinds of inks have blued paper. There has been a lot of discussion about the blued paper in the COGH thread, if you want to read more about it. So, even though I never set out to learn about stamp or postmark inks, I have picked up some tidbits along the way.
|
|
stainlessb
Member
qaStaHvIS yIn 'ej chep
Posts: 4,645
What I collect: currently focused on most of western Europe, much of which is spent on France, Belgium, Germany and Great Britain Queen Victoria
|
Post by stainlessb on Apr 5, 2023 22:44:41 GMT
If the inks used a glycerine/glycerol base, that might explain why it might seep through and stain the back of the stamp. As the early papers used gelatins for sizing from animal ...renderings, i wonder if the glycerine was able to penetrate that and thus soak thru?
|
|
|
|
Post by smauggie on Apr 6, 2023 0:15:20 GMT
It depends on the country and the era.
|
|
|
|
Post by gstamps on Apr 6, 2023 8:21:40 GMT
Many postal cancellations of German stamps from the period of inflation (1916-1923) are fake and looking for information I found this information on the "stamporama" website: << 1. Genuine postal cancels used an oily ink (referring only to general post office cancels, not special cancels which I have seen to clearly use non-oily ink). This often results in the following... 2. ...genuine cancels often "bleed" through slightly or significantly to the back-side 3. ...genuine cancels often "spread out" giving the appearance of blurriness or unsharp lines/curves, sometimes even resulting in "blotching" 4. ...a lot of the genuine cancels that I've seen tend NOT to be dark black, and I was wondering if this is caused in part by the "bleeding" out/thru >> An example:   |
|
