Provided is an amidate compound represented by the formula (1): wherein A is a substituted or unsubstituted hydrocarbon group, n is an integer of 1 or more, and D is a nitrogen-containing organic group represented by the formula (2): wherein R1, R2, and R3 are the same or different, and are each a hydrocarbon group that may contain a heteroatom; some or all of R1, R2, and R3 may be bonded together to form a ring structure; X is a nitrogen atom, an oxygen atom, or a sulfur atom; and a is 0 or 1, wherein a is 1 when X is a nitrogen atom, and a is 0 when X is an oxygen atom or a sulfur atom.