We prove the existence of regular solutions for a class of quasi-linear partial neutral functional differential equations with unbounded delay that can be described as the abstract retarded functional differential equation <IMG SRC="/fbpe/img/proy/v21n1/for07.jpg" WIDTH=522 HEIGHT=33>where A is the infinitesimal generator of a strongly continuous semigroup of bounded linear operators on a Banachspace X and F, G are appropriated functions