An approach to the definition of fuzzy logical connectives is proposed
using matrix logic. This matrix representation of Boolean logical ope
rators enables us to link together conjunction, disjunction and negati
on differently from the traditional De Morgan law. In this framework t
he Frank family appears as the only possibility. In addition, the para
meters in conjunction and in disjunction are reciprocal to each other.
The usefulness of this case is illustrated by two applications.