Abstract: | It is shown that for f > 0 there are two constants c 1 , c 2 > 0 and a holomorphic map f from the unit disk ${\shadD} {\rm of} {\shadC}$ into ${\shadC}^2$ such that $ c_1(1-|z|)^{-\alpha }\le |\,f'(z)|\le c_2(1-|z|)^{-\alpha } $ for all $ z\in {\shadD}$ . Moreover, this existence is effectively used in the study of invariance of the Bloch-type spaces under composition, but also in the discussion of embedding the Bloch-type spaces via derivation into the Lebesgue, mixed-norm and Coifman-Meyer-Stein tent spaces. |