A large-scale application of carbenes is the industrial production of tetrafluoroethylene, the precursor to Teflon.  Tetrafluoroethylene is generated via the intermediacy of difluorocarbene:
: CHClF  →   CF  +  HCl
:2 CF  →   FC=CF
The insertion of carbenes into C–H bonds has been exploited widely, e.g. the functionalization of polymeric materials and electro-curing of adhesives.  Many applications rely on synthetic 3-aryl-3-trifluoromethyldiazirines (a carbene precursor that can be activated by heat, light, or voltage) but there is a whole family of carbene dyes.