After a prolonged stay in Morocco where he was wounded during the Great War, he exhibited for the first time at the Salon d'Automne in 1919 and resumed painting in Paris under the tutelage of his friend Jacques-Emile Blanche. He subsequently exhibited at the Salon des Tuileries, at the Salon des Indépendants, and the Galerie Charpentier devoted several exhibitions to him.
Gaigneron frequented both French literary circles and the private mansions of the Faubourg Saint-Germain. A friend of Proust, Cocteau and Morand, he notably painted the portrait of François Mauriac, donated by the author to the Jacques Doucet library, the portrait of Poulenc, kept at the library museum of the Paris Opera, and the portrait of Anna de Noailles kept at the Carnavalet Museum.
The Brooklyn Museum in New York holds two of his paintings.