I just read an old article in a German stamp journal saying that additionally to the known silkote paper there was another try for different paper in the 1950s for the 2c #1033 stamp which is called in German "Panton-Papier", so "panton paper". When I search in the internet I only get "Pantone" results which is not the correct paper, but colors.
So has there been another experimental paper for the 1033 and how translates "Panton" then into English?
Ken Lawrence refers to this paper in his book The Liberty Series on page 20: "Another test printing of the 2c Jefferson stamp on Printone Litho Plate paper (some published references have reported this as Pantone Litho Plate paper) in January 1955 seems to have vanished without a philatelic trace, except in the literature. These tests led to no practical result, because the Oxford paper was deemed adequate, and continued as the BEP's choice for stamps printed on the new web-fed rotary presses. Nevertheless, the stamps exist for the same reason as the scarce bluish paper varieties of the 1909 Washington-Franklin stamps and the 2c Lincoln Memorial commemorative (Scott 357-366, and 369)."