Patent ID: 7582390

Claim:
A two-photon absorbing polymerization method comprising: a first step of irradiating light on a composition comprising a free radical polymerizable compound capable of a two-photon absorption to form only a latent image; and a second step of exciting the latent image by an application of heat to cause a polymerization, wherein as a two-photon absorbing compound, a cyanine dye, a merocyanine dye, an oxonol dye, a phthalocyanine dye or a compound represented by the following formula (1) is used: wherein R 1 , R 2 , R 3 and R 4 each independently represents a hydrogen atom or a substituent and some of R 1 , R 2 , R 3 and R 4 may combine with each other to form a ring; n and m each independently represents an integer of 0 to 4 and when n and m each is 2 or more, multiple R 1 s, R 2 s, R 3 s or R 4 s may be the same or different, provided that n and m are not 0 at the same time; and X 1 and X 2 each independently represents an aryl group, a heterocyclic group or a group represented by formula (2): wherein R 5 represents a hydrogen atom or a substituent, R 6 represents a hydrogen atom, an alkyl group, an alkenyl group, an aryl group or a heterocyclic group, and Z 1 represents an atomic group for forming a 5- or 6-membered ring.