Abstract: A method of applying a two-part liquid composition to a workpiece is provided. In particular, a two-step method is provided wherein a first liquid composition is applied to the workpiece by roll coating, and a second liquid composition is applied by spraying the workpiece. Generally, the first liquid composition is a polyurethane adhesive and the second liquid composition is a polyurethane catalyst. By applying the reactive components of the polyurethane composition in two steps, the open time may be controlled.

Abstract: A roll coating machine for applying liquid materials onto sheet material workpieces. The machine has particular application in the area of coating flexible foam sheets with stiffening or adhesive agents. The roll coater incorporates mechanisms for controlling the spacing between coating rollers which apply the liquid materials onto one or both sides of the workpiece and enables automatic adjustment for various thickness of material. Automatic adjustment is provided through accurate force balancing of one of the rollers and applying a highly controlled net force acting on the rollers such that the rollers self-adjust based on compression of the workpiece. Another mechanism provided in the machine of this invention incorporates pre-gauging and a cam adjustment mechanism for setting separation distance which can be used independently or in conjunction with a force balancing approach mentioned previously.