There was a collapse in the vegetable tannin market in the 1950s–1960s, due to the appearance of synthetic tannins, which were invented in response to a scarcity of vegetable tannins during World War II.
Houbo un colapso no mercado de taninos vexetais nas décadas de 1950 e 1960, debido á aparición de taninos sintéticos no período de escaseza de taninos vexetais durante a Segunda Guerra Mundial.