A silsesquioxane compound represented by the following formula (I): (R
a
SiO
1.5
)
n
, wherein R
a
is, each independently at each occurrence, R
b
or R
c
; provided that at least one R
a
is R
b
; R
b
is —R
1
—CF
2
—R
2
—R
3
; R
1
is a divalent group; R
2
is a divalent polymer chain; R
3
is a halogen atom or a hydrogen atom; R
c
is a hydrogen atom, an alkyl group, a phenyl group, or —(OSiR
15
2
)
j
—R
15
; R
15
is, each independently at each occurrence, a hydrogen atom or an alkyl group having 1 to 6 carbon atoms; j is, each independently at each occurrence, an integer of 1 to 3; and n is an arbitrary integer.