The enclosure member is suitably any coating which is permeable, either due to the permeability of the coating material and from flaws, fissures, holidays and the like in the coating, to at least one fluid found in the subterranean formation being treated or in the fluid injected with the capsules into the formation and which is capable of releasing the breaker, at the temperatures existing in the formation, due to {TAIL ~ an increase} in {HEAD ~ the pressure} inside the capsule as compared to the environmental pressure 
The enclosure member is suitably any coating which is permeable , either due to the permeability of the coating material and from flaws , fissures , holidays and the like in the coating , to at least one fluid found in the subterranean formation being treated or in the fluid injected with the capsules into the formation and which is capable of releasing the breaker , at the temperatures existing in the formation , due to { TAIL ~ an increase } in { HEAD ~ the pressure } inside the capsule as compared to the environmental pressure
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