1956 – Camille Dreyfus dies. He was one of the founders of Celanese and was President of Celanese Corporation of America for 27 years. Following the death of his brother and co-founder, Henri in 1945, Camille Dreyfus was also Managing Director of British Celanese.

1945-1960 – In the U.S., Celanese establishes production plants in Texas (Bishop in 1945, and Pampa in 1952) for the production of acetaldehyde, formaldehyde, methanol und acetone. But Celanese fibers remain the company's most important product line. The use of acetate tow in cigarette filters opens up a new business area.

1944 – Celanese Mexicana SA, a publicly traded company, is formed by Celanese and a Mexican group headed by Banco Nacional de Mexico SA. and begins producing acetate fiber at its plant near Ocotlan in 1947.

1930 –Celanese Corporation of America commences trading on the New York Stock Exchange.

1927 –  The American Cellulose & Chemical Manufacturing Co. changes its name to "Celanese Corporation of America". The company, which will move on to produce plastics and chemicals, as well as fibers, will become one of the largest chemicals manufacturers in the country.

1926 – Celanese Canada, a publicly traded company, is formed, with Amcelle owning the majority share. From 1927 onwards, artificial silk is produced at the Canadian factory in Drummondville.

1924 – Amcelle begins producing cellulose acetate in Cumberland, Maryland.

1921 – British Celanese begins commercial production of acetate yarn, taking advantage of a number of its new inventions, ranging from the technique used to spin thread to the treatment of dyed fibres. This change in direction ensures the company's survival.

1918 – The company gets into difficulties when all its paint contracts are cancelled after World War I. The Dreyfus brothers concentrate on the production of acetate fibers. "British Cellulose & Chemical Manufacturing Co." changes its name to "British Celanese Limited.

1918 – Under the guidance of Camille Dreyfus, "The American Cellulose & Chemical Manufacturing Company" (known as "Amcelle" for short), is founded in New York.  The company commences building a production facility in Cumberland, Maryland.

1916 – The British government invites the Dreyfus brothers to Britain to produce their new airplane paint, along with the intermediate product acetic acid, which was being imported from Canada at the time due to World War I. The British Government patented the process developed by Henri Dreyfus, which lowered the costs of acetic acid anhydride production. "British Cellulose & Chemical Manufacturing Co." is set up. Henri Dreyfus manages the company with a workforce of 14,000.

1913 – The company "Cellonit" is established. Cellonit contributes greatly to the development of new film materials and finds a sponsor in the Parisian film industrialist Pathe. The product line is diversified to include paints for German airplanes and Zeppelins.

1912 – Henri Dreyfus, who was working for Hoffmann La Roche at the time, asks the entrepreneur Alexander Clavel-Respinger for financial support and assistance in the production of fireproof celluloid out of cellulose acetate. On December 28, 1912, Clavel, along with Henri and his brother Camille set up "Cellonit Gesellschaft Dreyfus & Co." in Basle.