Production of urethane foams and laminates thereof
AssigneeBeatrice Foods Co.
InventorsHarry M. Anderson, Jr., Charles K. Knisely
Life of this patent
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Abstract
Thin flexible urethane foam film layers are produced by spreading a layer of polyurethane reactants over a carrier sheet at a uniform layer thickness. The polyurethane reactants consist essentially of an isocyanate and a hydroxyl terminated polyol having an inorganic carbon dioxide producing blowing agent incorporated therein and being free of water. The unconfined film layer is then heated to a temperature in the range of from 260.degree.F to 390.degree.F to cause gellation and release of the carbon dioxide in the mixture with final formation of a uniform thickness flexible polyurethane foam product.
Claims11
A method of forming a flexible polyurethane foam layer having uniform controlled film layer thickness,
- said method comprising,
- spreading a layer of a polyurethane reactants containing mixture over a carrier surface in a uniform layer thickness,
- said polyurethane reactants consisting essentially of an isocyanate and a hydroxyl terminated polyol having from 1 to 9% by weight thereof of an inorganic carbon dioxide producing blowing agent incorporated therein,
- and heating said layer to a temperature in the range of from 260.degree.F to 390.degree.F to cause release of carbon dioxide in said mixture and formation of polyurethane foam in a uniform thickness final product.
In a method of forming polyurethane foam layers having hardness values of 50 Shore A to 80 Shore A from polyurethane reactants containing mixtures comprising an isocyanate and a polyol,
- the improvement comprising,
- incorporating in the reactants from 1 to 9% by weight of powdered sodium bicarbonate nonreactive with the isocyanate and capable of releasing carbon dioxide at temperatures in the range of from 260.degree.F to 390.degree.F,
- positioning a film of from 0.003 inch to 0.07 inch of said mixture on a carrier layer in a uniform thickness,
- and heating said film to form a urethane foam having a uniform thickness of from 0.006 to 0.140 inch.
Dependencies are inferred from the claim text.