Glass fiber duct board with coated grooves and the method of making the same

A method of making a glass fiber duct board with coated grooves, comprising:

• passing a glass fiber duct board having a major surface that is precoated with a polymeric coating to encapsulate glass fibers within the major surface of the duct board through a groove cutting station and a groove coating station;
• cutting a plurality of spaced-apart grooves of a selected configuration in the major surface of the duct board with cutting tools as the duct board passes through the groove cutting station so that the duct board can be folded along the grooves;
• applying a foamed polymeric latex coating material to all surfaces of each of the grooves with nozzles located downstream of the cutting tools as the duct board passes through the groove coating station;
• and
• engaging the foamed polymeric latex coating material applied by the nozzles with wiper blades located downstream of the nozzles;
• the wiper blades each having edges which conform in configuration to a transverse configuration of the groove with which the wiper blade is used and which are spaced a selected distance from the surfaces of the groove to distribute the foamed polymeric latex coating material across the surfaces of the groove and to set the thickness of the layer of foamed polymeric coating material formed on the surfaces of the groove to thereby encapsulate glass fibers and dust within the surfaces of the groove;
• and the wiper blades each having extensions which extend upstream from the wiper blade adjacent upper longitudinal edges of the groove with which the wiper blade is used and cooperate with the precoated upper major surface of the glass fiber insulation board to confine the foamed polymeric latex coating material being applied to the groove within the groove.