| abstract |
A negative-type planographic printing plate having, disposed on a support, a recording layer comprising an image recording material which contains an infrared ray absorbing agent and can be recorded by irradiation with an infrared ray, in which, as for the infrared ray absorbing agent comprising a cyanine dye, at least one of substituents on nitrogen atoms at both ends was selected from the group consisting of the following substituents: —C(═X)R 1 ; —C(═X)NR 2 R 3 ; —CH≡CR 4 R 5 ; —C≡CR 6 ; —CHR 7 R 8 ;—CR 9 R 10 R 11 ; and —Ar, wherein X represents O, S or Se; R 1 to R 6 each independently represent H or a hydrocarbon group having 20 or fewer carbon atoms which may have a substituent; R 7 to R 11 each independently represent a hydrocarbon group having 20 or fewer carbon atoms which may have a substituent; and Ar represents an aromatic group which may have a substituent. |