The invention provides a cushion for a polishing pad, wherein, when a dynamic compression viscoelasticity measurement is performed under 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 {HEAD ~ the deformation amount} to {TAIL ~ the maximum value} of the dynamic stress is 0.5 μm/kPa or more 
to
The invention provides a cushion for a polishing pad , wherein , when a dynamic compression viscoelasticity measurement is performed under 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 { HEAD ~ the deformation amount } to { TAIL ~ the maximum value } of the dynamic stress is 0.5 μm / kPa or more
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