| abstract |
Microparticles comprising a compound represented by general formula (1) [wherein R 1a and R 1b may be the same as or different from each other, and independently represent an alkyl group, an aryl group or a heteroaryl group; R 2 and R 3 independently represent a hydrogen atom or a substituent, provided that at least one of R 2 and R 3 is an electron-withdrawing group, and R 2 and R 3 may together form a ring; and R 4 represents a hydrogen atom, an alkyl group, an aryl group, a heteroaryl group, a substituted boron or a metal atom, and R 4 may be bound covalently or coordinately to R 1a , R 1b and/or R 3 ]. |