| abstract |
FIELD: chemistry. n SUBSTANCE: invention relates to a marking composition designed to form marks or signs on substrate after laser irradiation, and to a method for laser marking substrate. The composition contains reinforcing agents for laser marking, such as nitrides, carbides, silicides or combinations thereof. The agent reinforcing the absorption of laser radiation is selected from a group consisting of: FeMn, (Co)Mo, CaSi, Cu 5 Si, FeSi, Fe 5 Si 2 , MgFeSi, MnSi 2 , MoSi 2 , Ni 2 Si, TiSi 2 , ZrSi 2 , WSi 2 , YSi, Al 4 C 3 , boron carbide (B 4 C), CaC 2 , Fe 3 C, Fe 7 C 3 , Fe 2 C, LaC 2 , Mg 2 C, Mg 2 C 3 , MoC, Mo 2 C, Mo 3 C 2 , Ta 4 C 3 , YC 2 , AlN, BN, Fe 2 N, Fe 3 N, Fe 4 N, Fe 7 N 3 , Fe 16 N 2 , MoN, Mo 2 N, Si 3 N 4 , TiN, W 2 N, WN, WN 2 , ZrN and combinations thereof. After placing the marking composition on substrate and exposure to laser radiation, the marking composition forms a mark on substrate that has a negative dark contrast value of at least -1, compared to the mark made by the marking composition without a reinforcing agent. n EFFECT: obtaining a marking composition. n 6 cl, 20 dwg, 11 tbl |