Abstract: A negative-working infrared radiation-sensitive lithographic printing plate precursor can be imaged and developed on-press to provide a lithographic printing plate. Such precursor has an initiator composition that contains compound A of Structure (I) and one or more compounds collectively as compound B of Structure (II) or Structure (III): wherein R1, R2, R3, R4, R5 and R6 are independently alkyl groups each having 3 to 6 carbon atoms; at least one of R3 and R4 is different from R1 or R2; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R3 and R4 is 0, 1, or 2; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R5 and R6 is 0, 1, or 2; and X1, X2 and X3 are the same or different anions.

Abstract: A negative-working infrared radiation-sensitive lithographic printing plate precursor can be imaged and developed on-press to provide a lithographic printing plate. Such precursor has an initiator composition that contains compound A of Structure (I) and one or more compounds collectively as compound B of Structure (II) or Structure (III): wherein R1, R2, R3, R4, R5 and R6 are independently alkyl groups each having 3 to 6 carbon atoms; at least one of R3 and R4 is different from R1 or R2; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R3 and R4 is 0, 1, or 2; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R5 and R6 is 0, 1, or 2; and X1, X2 and X3 are the same or different anions.

Abstract: A negative-working infrared radiation-sensitive lithographic printing plate precursor can be imaged and developed on-press to provide a lithographic printing plate. Such precursor has an initiator composition that contains compound A of Structure (I) and one or more compounds collectively as compound B of Structure (II) or Structure (III): wherein R1, R2, R3, R4, R5 and R6 are independently alkyl or alkoxy groups each having 2 to 9 carbon atoms; at least one of R3 and R4 is different from R1 or R2; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R3 and R4 is 0 to 4; the difference of total number of carbon atoms in R1 and R2 and the total number of carbon atoms in R5 and R6 is 0 to 4; and X1, X2 and X3 are the same or different anions.

Abstract: The present invention relates to a lithographic printing plate precursor, comprising: a substrate; and an imaging layer formed on the substrate, wherein the imaging layer is prepared from a composition comprising at least one radical-polymerizable compound, at least one radical polymerization initiator, and at least one polymer particle which has an average particle diameter of 300 nm or more, and two or more poly(alkyleneoxide) moieties. The present invention can provide a lithographic printing plate precursor which is on-press developable and has excellent on-press development stability overtime and printing properties.

Abstract: A seal (21) is constituted by an outer lip portion (22) to be held in abutting engagement with an outer link portion (9) of a crawler belt (7), an inner lip portion (23) to be held in abutting engagement with a bush (11), and an interconnecting bridge portion (24) bridged and connected between the outer and inner lip portions (22, 23). The outer lip portion (22) on the side of track link, the inner lip portion (23) on the side of bush, and outer bridge portion (24A) and inner bridge portion (24B) of the interconnecting bridge portion (24) are formed in thicknesses (T1, T2, T1? and T2?), respectively, which are in the relations of (T2?T2?>T1?T1?). A maximum outside diameter portion (24C) of the interconnecting bridge portion (24) is located radially outward of a median point between inner and outer peripheral ends of the lip portion (23) on the side of bush. The inner lip portion (23) as a whole is uniformly pressed against an end face (11A) of the bush (11) by the interconnecting bridge portion (24).

Abstract: A seal (21) is constituted by an outer lip portion (22) to be held in abutting engagement with an outer link portion (9) of a crawler belt (7), an inner lip portion (23) to be held in abutting engagement with a bush (11), and an interconnecting bridge portion (24) bridged and connected between the outer and inner lip portions (22, 23). The outer lip portion (22) on the side of track link, the inner lip portion (23) on the side of bush, and outer bridge portion (24A) and inner bridge portion (24B) of the interconnecting bridge portion (24) are formed in thicknesses (T1, T2, T1′ and T2′), respectively, which are in the relations of (T2≈T2′>T1≈T1′). A maximum outside diameter portion (24C) of the interconnecting bridge portion (24) is located radially outward of a median point between inner and outer peripheral ends of the lip portion (23) on the side of bush.

Abstract: The present invention concerns a crawler belt (7) incorporating a sealing devices (21), which are each constituted by a coned disc spring (23) and a seal ring (22), to seal up gap spaces between track links (8) and bushes (13). A seal anchor hole (12) is provided in each one of outer link portions (9) of track links (8) of the crawler belt (7), and the sealing device (21) is fitted in the seal anchor hole (12) between an outer link portion (9) and an opposing end face (13A) of a bush (13). The sealing device (21) includes the seal ring (22) in the shape of an O-ring, and the coned disc spring (23) which is arranged to press the seal ring (22) resiliently against peripheral wall surface (12B) of the seal anchor hole (12) and the end face (13A) of the bush (13).