After the end of the second World War the relationship between Cassinari and Morlotti consolidated in Milan: together they planned the manifesto for the Labour Day.
At the Premio Fra Galgario, an exhibition for self-portraits and portraits organized in Bergamo, Cassinari, Morlotti and Bernasconi carried off an equal prize of £ 60.000; they also explained the function of portraits and the role and the meaning of modern painting in an interview, which was published in the Italian newspaper L’Unità. Moreover they exhibited their paintings at the L’isola di Genova art gallery too. For his painting Ritratto di vecchia signora (Portrait of Old Lady), already belonging to Jesi collection, Cassinari won the first prize at the Pro Fondo Matteotti exhibition, which was held at the Guglielmi Gallery in Milan. In December, together with De Grada, De Micheli, Gatto, Guttuso, Morlotti, Treccani, Terra and Vittorini, he founded the periodical Il 45, but only three issues were then published.