On cross product Hopf algebras

Let A and B be algebras and coalgebras in a braided monoidal category C, and suppose that we have a cross product algebra and a cross product coalgebra structure on A⊗B. We present necessary and sufficient conditions for A⊗B to be a bialgebra, and sufficient conditions for A⊗B to be a Hopf algebra. We discuss when such a cross product Hopf algebra is a double cross (co)product, a biproduct, or, more generally, a smash (co)product Hopf algebra. In each of these cases, we provide an explicit description of the associated Hopf algebra projection.