Patent ID: 7435369

Claim:
A method of manufacture of gypsum board having fiber face sheets, comprising: providing a first gypsum slurry having a first consistency continuously passing through a first gypsum slurry transport receptacle; providing an in-line gypsum slurry transport receptacle having a discrete point of fluid communication with the first gypsum slurry transport receptacle; receiving and transporting through said in-line gypsum slurry transport receptacle a stream of said first gypsum slurry and simultaneously modifying said first gypsum slurry in said in-line gypsum slurry transport receptacle after said discrete point to obtain a second gypsum slurry having a second consistency; modifying the first gypsum slurry by homogeneously mixing an additive into said first gypsum slurry in the first gypsum slurry transport receptacle after said discrete point; depositing a predetermined amount of said modified first gypsum slurry onto at least one first continuous fiber face sheet; transporting said first continuous fiber face sheet, with said modified first aypsum slurry impregnated therein, through a second gypsum slurry application station; depositing said second gypsum slurry onto said first fiber face sheet at said second gypsum slurry application station, thereby causing said second gypsum slurry to be essentially evenly distributed over an upwardly facing top surface of said first fiber face sheet.