Patent ID: 8283393

Claim:
A method of producing a polyurethane dispersion comprising the steps of: providing a device for producing a dispersion comprising: a first stator; a second stator; a shell encasing said first stator and said second stator; a rotor, wherein said rotator is disposed therebetween said first stator and said second stator thereby forming a first chamber and a second chamber, wherein said first chamber is a high shear chamber, and said second chamber is a low shear chamber; at least one first inlet port into said first chamber; at least one outlet port out of said second chamber; and at least one second inlet port into said second chamber; introducing a prepolymer phase and an aqueous phase into said first chamber via said first inlet ports; emulsifying said prepolymer phase in said aqueous phase; thereby producing a prepolymer emulsion; introducing a chain extender agent into said emulsion in said second chamber via said second inlet port; chain extending said prepolymer; and thereby producing a polyurethane dispersion.