[1] With his brother-in-law Léon Whittman, Etienne began to manufacture photographic products, which up to then the business had only retailed, under the "P.W."

In 1859 Poulenc opened a factory in Ivry-sur-Seine that prepared salts of iron and antimony, and many products needed for manufacture and processing of the new gelatin-silver bromide plates, which had replaced collodion: ammonium ferric citrate, sodium acetate, and compounds for fixing and developing the photographs.

They set up a new factory in Montreuil, Seine-Saint-Denis that manufactured antimony, iron, tin and silver salts for glassware and ceramics, and also produced laboratory reagents.

[8] The company was the leading supplier of fine chemicals to pharmacists and researchers, and the leader source of photographic supplies.

[7] After Camille joined, the company opened a research laboratory to produce pure and rigorously controlled mineral salts.

[7] Camille became interested in radium in 1900 and met Pierre and Marie Curie, who gave him a sample of the metal so he could study its effects.

[12] In 1903 it opened a new establishment on the rue du Quatre-Septembre in Paris dedicated to photography products and materials with a projection room in the basement that could seat 100 people.

He was a pupil of Friedel and Moureu who had studied in the German laboratories of Ludwig Gattermann in Heidelberg, Hermann Emil Fischer in Berlin and Richard Willstätter in Munich.

[14] In 1903, Ernest Fourneau took over the management of a newly created pharmaceutical research department whose laboratories were located in Ivry.

[14] At the end of 1903 Fourneau and Poulenc frères filed the patents for stovaïne, the first commercially exploitable synthetic local anesthetic which remained in use until the 1940s.

[5] In 1910 Fourneau accepted the directorship of the Pasteur Institute's therapeutic chemistry section, with the condition that he maintained his ties with Poulenc Frères.

[14] The relationship with the Paris-based Pasteur Institute, a leading medical research center, gave the company a valuable advantage.

[11] The Poulenc brothers became interested in the research into catalytic hydrogenation being undertaken by Paul Sabatier and Jean-Baptiste Senderens in Toulouse.

[16] The outbreak of World War I (1914–18) brought new business to most French chemical companies, including Poulenc Frères.

It started producing German products that could no longer be obtained in France and England, including the syphilis treatments salvarsan (arsphenamine) and neo-salvarsan.

[18] In 1928 the Établissements Poulenc Frères merged with the Société chimique des usines du Rhône, which had been founded in 1895, to form Rhône-Poulenc.