Mr. Halpern as an inventor

I knew Mr. Halpern started his business in mimeograph printing ink.       I did not know him to be an inventor but a search in internet showed he had a patent on a heated stylus  for a heat sensitive master in 1946.          Knowing a bit of stencil technology, this was a revelation.       Many of the readers probably know that in the 70's and 80's there were  electronic stencil master making machines using a heat sensitive master.      I remember Mr. Halpern was interested in getting into the business of making such master at Polychrome but we at R&D failed to find an alternative route to make such master.   So he arranged to buy a master roll from other manufacturer (Litton Industry? who owned a patent?).     If we went back to 1946 there may have been such stencil master composition described already for the public.        On the other hand the stencil business eventually died out in favor of offset and electrostatic copying process so we were not wrong in focusing our efforts on developing offset technology.
So now we know Mr. Halpern was not only a businessman but also was an inventor.     (Yes he always had ideas on many  many things!)

Here is his US Patent  2474312