We have a kynar coated metal roof that was primed with an acrylic primer and then coated with a dark blue acrylic elastomeric paint. It was coated during spring with moderate weather. The roof surface was dry. Within a few days the coating blistered severely. The blisters were cut out; only the coating was delaminated, the primer was well bonded. Some of the blisters held moisture, most were dry. The blisters were cut out and the roof was reprimed and recoated. The coating blistered again as it had before. It was then revealed that the dark blue coating had been blended without a tint base; the pigment was added directly to a white or gray (or a mixture thereof) paint. We suspect that the CPVC was greatly exceeded when the blue pigment was added to the white and/or gray paint, would this cause the coating to blister? What test needs to be performed to determine the PVC?