Although some book reports that the celluloid was introduced on the market by [[Sheaffer]] actually the first American company to have used it extensively in its production was [[LeBoeuf]], who used it for its fountain pen starting from about 1920 thanks to a patent ({{Cite patent|US|1302935}}) for the production of pipes in this material, the [[Conway Stewart]] contends this leadership, asserting that they were the first manufacturer to have produced (still in those years) the first pen in celluloid. | Although some book reports that the celluloid was introduced on the market by [[Sheaffer]] actually the first American company to have used it extensively in its production was [[LeBoeuf]], who used it for its fountain pen starting from about 1920 thanks to a patent ({{Cite patent|US|1302935}}) for the production of pipes in this material, the [[Conway Stewart]] contends this leadership, asserting that they were the first manufacturer to have produced (still in those years) the first pen in celluloid. |