The invention provides a cushion for a polishing pad, wherein, when {HEAD ~ a dynamic compression viscoelasticity measurement} is performed under {TAIL ~ conditions} of 23° C., a static load of 27.6 kPa, a frequency of 11 Hz and an amplitude of 1 μm, a phase difference between dynamic stress and deformation is 4° or less, and a ratio of the maximum value of the deformation amount to the maximum value of the dynamic stress is 0.5 μm/kPa or more 
is performed under
The invention provides a cushion for a polishing pad , wherein , when { HEAD ~ a dynamic compression viscoelasticity measurement } is performed under { TAIL ~ conditions } of 23 ° C. , a static load of 27.6 kPa , a frequency of 11 Hz and an amplitude of 1 μm , a phase difference between dynamic stress and deformation is 4 ° or less , and a ratio of the maximum value of the deformation amount to the maximum value of the dynamic stress is 0.5 μm / kPa or more
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