  The purpose of this article is to prove the H\"older continuity up to the
boundary of the displacement vector and the microrotation matrix for the
quasistatic, rate-independent Armstrong-Frederick cyclic hardening plasticity
model with Cosserat effects. This model is of non-monotone and non-associated
type. In the case of two space dimensions we use the hole-filling technique of
Widman and the Morrey's Dirichlet growth theorem.
