Ink composition, inkjet recording method, method of producing planographic printing plate, and planographic printing plate

An ink composition comprising:

• (A) a polymerization initiator,
• (B) a polymerizable compound,
• (C) a colorant, and
• (D2) at least one compound selected from the group consisting of compounds represented by the following formula (II) and formula (III), wherein the at least one compound is contained in the ink composition in a range of from 3 to 20 mass % with respect to the total mass of the ink composition:
• wherein, in formula (II) or formula (III), A1 and A2 each independently represent an alkylene group having 1 to 4 carbon atoms;
• R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aryl group having 6 to 10 carbon atoms, an acyl group having 2 to 20 carbon atoms, or an allyl group;
• X represents an organic group having k valence;
• m and n each independently represent an integer of from 0 to 30, the sum of m and n in a molecule being 4 or more;
• and k is an integer of from 2 to 6.