Patent ID: 8900507

Claim:
A laser-engraveable composition comprising one or more elastomeric rubbers in an amount of at least 30 weight % and up to and including 80 weight %, based on the total laser-engravable composition weight, wherein the laser-engraveable composition further comprises at least 10 parts and up to and including 100 parts of one or more controlled long chain branching ethylene-propylene-diene (CLCB EPDM) elastomeric rubbers, based on parts per hundred of the total weight of elastomeric rubbers (phr) in the laser-engraveable composition, the laser-engraveable composition further comprising at least the following component b), with or without the following component a): a) at least 2 phr and up to and including 30 phr of a near-infrared radiation absorber and at least 1 phr and up to and including 80 phr of an inorganic, non-infrared radiation absorber filler, wherein the weight ratio of the near-infrared radiation absorber to the inorganic, non-infrared radiation absorber filler is from 1:40 to 30:1, and b) at least 2 phr and up to and including 30 phr of a near-infrared radiation absorber, and at least 3 phr and up to and including 20 phr of a vulcanizing composition that comprises a mixture of at least first and second peroxides, wherein the first peroxide has a t 90 value of at least 1 minute and up to and including 6 minutes as measured at 160° C., and the second peroxide has a to value of at least 8 minutes and up to and including 20 minutes as measured at 160° C., and wherein the weight ratio of the near-infrared radiation absorber to the vulcanizing composition is from 1:10 to 10:1, and comprising a conductive or non-conductive carbon black, carbon fibers, or carbon nanotubes as the near-infrared radiation absorber.