On acyclic edge coloring of planar graphs without intersecting triangles

Let Δ denote the maximum degree of a graph. Fiamčík first and then Alon et al. again conjectured that every graph is acyclically edge ( Δ + 2 ) -colorable. Even for planar graphs, this conjecture remains open. It is known that every triangle-free planar graph is acyclically edge ( Δ + 5 )-colorable. This paper proves that every planar graph without intersecting triangles is acyclically edge ( Δ + 4 ) -colorable.