In photography, ADOX is a trademark with a long history. It was originally a brand name used by the German company, Fotowerke Dr. C. Schleussner GmbH of Frankfurt am Main, the world's first photographic materials manufacturer. The company's founder, Dr. Carl Schleussner, did pioneering work on the wet-collodion process during the early years of photography, and formed his manufacturing company in 1860. Working with the physicist Wilhelm Röntgen, discoverer of X-rays, Dr. Schleussner invented the first X-ray plate.
The Schleussner firm began marketing cameras under the ADOX brand name in the first third of the 20th century and, recognizing the growing importance of the brand, renamed itself "Adox Fotowerke Dr. C. Schleussner GmbH." In 1952 they introduced a line of very sharp 35 mm films under the ADOX brand.
In 1962, the Schleussner family sold its photographic holdings to DuPont, an American company. DuPont became owners of the trademark, and registered it in the United States.
DuPont licensed the Adox film technology, but not the trademark, to Fotokemika, a manufacturer in Yugoslavia, who used the technology for films sold under their Efke trademark. DuPont kept the Adox trademark, transferring it to a subsidiary, Sterling Diagnostic Imaging, for its Adox brand X-ray films. They still apply it to an industrial chemical, sodium chlorite.
In 1999, Sterling was bought by the German company Agfa, and was absorbed into Agfa's Health Sciences unit. In this roundabout way, the Adox photographic trademark once again became German. Agfa did not use the Adox trademark, and the mark was removed from the German Patent Office trademark registry in March, 2003. It was almost immediately revived by companies in Canada, the United States, and FOTOIMPEX in Germany, none of which are related to the original Schleussner firm.