Methods for preparing open-celled polyurethane foams, systems for use therein, and open-celled polyurethane foams produced thereby
AssigneeCovestro LLC
InventorsBin Lee, Paul O. Barley
Life of this patent
Estimating the term…
Abstract
Disclosed are methods and systems for preparing open-celled polyurethane foams by a discontinuous box foam process in which (a) a polyurethane foam-forming composition is deposited into a container having a gas-permeable base and (b) the polyurethane-foam forming composition is allowed to form an open-celled polyurethane foam in the container. In these methods and systems, the gas-permeable base is heated before, during, and/or after step (a) and heating is continued during at least a portion of step (b).
Claims18
A method for preparing an open-celled polyurethane foam, comprising:
- (a) depositing a polyurethane foam-forming composition comprising a polyisocyanate component and a polyol component into a container having a gas-permeable base, wherein the polyol component comprises:
- (i) 20 to 40% by weight, based on the total weight of the polyol component, of a polypropylene oxide-based polyether diol having an OH number in the range of from 450 to 600;
- (ii) 30 to 50% by weight, based on the total weight of the polyol component, of a poly(propylene/ethylene oxide) glycerin-initiated polyether triol having an OH number in the range of from 26 to 34;
- and
- (iii) 10 to 30% by weight, based on the total weight of the polyol component, of a polypropylene oxide-based polyether triol having an OH number in the range of from 400 to 550;
- and
- (b) allowing the polyurethane-foam forming composition to form an open-celled polyurethane foam in the container,
- wherein the method comprises heating the gas-permeable base, with a heating device comprising a heating pad, matt or plate disposed beneath the gas-permeable base, before, during, and/or after step (a) and continuing the heating during at least a portion of step (b), and
- wherein the method is discontinuous.
A method for preparing an open-celled polyurethane foam, comprising:
- (a) depositing a polyurethane foam-forming composition comprising a polyisocyanate component and a polyol component into a container having a gas-permeable base, wherein the polyol component comprises:
- (i) 20 to 40% by weight, based on the total weight of the polyol component, of a polypropylene oxide-based polyether diol having an OH number in the range of from 450 to 600;
- (ii) 30 to 50% by weight, based on the total weight of the polyol component, of a poly(propylene/ethylene oxide) glycerin-initiated polyether triol having an OH number in the range of from 26 to 34;
- and
- (iii) 10 to 30% by weight, based on the total weight of the polyol component, of a polypropylene oxide-based polyether triol having an OH number in the range of from 400 to 550;
- and
- (b) allowing the polyurethane-foam forming composition to form an open-celled polyurethane foam in the container,
- wherein only the gas-permeable base and optionally a bottom portion of the side wails of the container are heated before, during, and/or after step (a) and continuing the heating during at least a portion of step (b), and
- wherein the method is discontinuous.
Dependencies are inferred from the claim text.