申请人:Kyoda Makoto
公开号:US20090227713A1
公开(公告)日:2009-09-10
A phosphorus compound represented by the formula (I):
wherein R
1
and R
2
are, the same or different, a hydrogen atom, a straight or branched-chain alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms which may be optionally substituted for an alkyl group having 1 to 4 carbon atoms, R
3
, R
4
, R
5
, R
6
and R
7
are, the same or different, a hydrogen atom or an aryl group having 6 to 12 carbon atoms which may be optionally substituted for an alkyl group having 1 to 4 carbon atoms, or R
3
and R
4
, R
4
and R
5
, R
5
and R
6
or R
6
and R
7
may form a 6 membered ring with carbon atoms wherein these groups bond a benzene ring provided that R
3
, R
4
, R
5
, R
6
and R
7
are not hydrogen atoms at the same time.