Outside Back Cover: Hinge‐Like Mechanochromic Mechanophores Based on [2.2]Paracyclophane (Angew. Chem. 37/2025)

Mechanochromic mechanophores function as force-reporting molecules in polymer materials. In their Research Article (e202510114), Yoshimitsu Sagara et al. demonstrate the first hinge-like mechanophore based on [2.2]paracyclophane. Polyurethane films covalently incorporating the mechanophore exhibit excimer-dominant emission in the force-free state. Upon mechanical activation, force-induced separation of the associated fluorophores leads to a change in fluorescence color from excimer-dominant bright yellow to monomer-dominant blue-green.