Abstract: The present invention relates to phthalocyanine compound of poly cross-linking type which is represented with the below formula 1 and is useful for preventing forgery and alternation due to a rapid velocity being responded to a gamma ray of Neutron, and an ink composition comprising it. wherein, M1 and M2 are any one selected from a group consisted of a metal, a metal oxide or a metal halide respectively and may be same or different, R is a hydrogen atom, a halogen atom, a hydroxyl group, an amino group, a hydroxysulfonyl group, an aminosulfonyl group, or an alky group having a substituent group having from 1 to 20 carbon atoms, and n is an integer of 0˜3.