CFC was phased out due to its role in world depletion of atmospheric ozone. As an interim measure, hydrochlorofluorocarbon blowing agents were used within the Nineteen Nineties and early into the 2000s. It was not until introduction of the third generation blowing agent, hydrofluorocarbon that a blowing agent with a zero ozone depletion ranking was obtainable. The development of the second and third generation blowing agents was technically challenging. Though the phase-ins of the new agents were typically profitable, product efficiency problems were skilled.
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