The invention provides a lighting device (1000) comprising (i) a light source (100) configured to generate light source light (101), wherein the light source (100) comprises a solid state light source, and (ii) a support (200) configured to support the light source (100), wherein the support (200) comprises a metal based thermally conductive material (201), wherein the lighting device (1000) further comprises (iii) a layered element (300), configured in physical contact with the support (200), wherein the layered element (300) comprises one or more layers (310), wherein the layered element (300) at least comprises an electrically insulating first layer (311), wherein at least part of the layered element (300) is configured between the light source (100) and the support (200) such that during operation part of the light source light (101) irradiates the layered element (300), wherein the layered element (300) comprises light reflective particles (410), wherein at least 50 wt. % of the particles have a flake-like shape.