Patent ID: 8828495

Claim:
A method for minimizing emissions of a polyisocyanate while spraying a mixture onto a surface, said method comprising the steps of: A. providing a polyisocyanate; B. providing a resin composition having a hydroxyl content of at least 400 mg KOH/g and comprising (i) a blowing agent that is a liquid under a pressure at least equal to atmospheric pressure, (ii) a first polyol selected from the group of a Mannich polyol, an autocatalytic polyol, and combinations thereof, (iii) at least one additional polyol other than the first polyol, and optionally: (iv) a catalyst, (v) a surfactant, and (vi) water; C. combining the resin composition with the polyisocyanate in the absence of other blowing agents to form the mixture; and D. spraying the mixture onto the surface to form a polyurethane foam having a closed cell content of at least 90 percent, wherein the mixture is sprayed through a spray nozzle at a spray angle corresponding to a control spray angle of from 15 to 125 degrees measured at a pressure of from 10 to 40 psi using water as a standard, and wherein the step of spraying produces less than 10 parts of the polyisocyanate per one billion parts of air within a semicircle emanating from the surface and having a radius of 3 feet measured from the surface according to OSHA Method 47.