52  US 8,691,490 B2  51  carbon atoms, and an oxoalkyl group having 4 to 20 carbon  atoms, specifically the same as  RL $^{04 }$and the like are exempli› fied.  Specifically, a repeating unit represented by the above- mentioned general formula (6) is exemplified by the follow- ing, but is not limited thereto. Although only a (meth)acrylic  acid ester is shown, the one intervened by a divalent connector  represented by the foregoing formula (L-2) or (L-2-2) may  also be used.  (~) (++)  /  ’j=o  i  ro  ~  \- H  H  H  H  (++)(++)  i  ro i  ro  (’  ~  (~)  /  Fo  (~) (++)  /  Fo  i  ro  -continued  H  H  H  H  (++)  (++)  i  ro  i  ro  ~  -1=>  (~)  /  Fo  (~)  /  Fo  (~)  /  Fo  ~  H  H  (++)  i  ro  12)  H  H  H  H  (++)  (++)  i  ro  i  ro  ~~  (~)  /  Fo  0  (~)  /  Fo  0  (~)  /  Fo  0  H  H  (++)  i  ro  0 