The invention provides a method for darkening treatment of black
polyester fabrics. The method comprises a first-stage darkening posttreatment procedure and a second-stage darkening posttreatment procedure, wherein the first-stage darkening posttreatment procedure comprises the following steps of: padding black
polyester fabrics in treating liquid of 10 to 60g / l organic
fluorine-type
polymer finishing agent or acrylic ester-type
polymer finishing agent, keeping the padding residue rate at 55 to 175 percent, performing
infrared drying,
roasting the
polyester fabrics, performing baking setting treatment at the temperature of between 175 and 215 DEG C for 30 to 90 minutes; and the second-stage darkening posttreatment procedure comprises the following steps of: padding the polyester fabrics obtained by the first-stage darkening posttreatment procedure in treating liquid of 10 to 85g / l hydrophilic linear
organosilicon finishing agent, keeping the padding residue rate at 45 to 150 percent, performing
infrared drying,
roasting the polyester fabrics, performing baking setting treatment at the temperature of between 180 and 220 DEG C for 30 to 90 minutes. By the technical scheme of the invention, the black depth value of the black polyester fabrics is increased by over 20 percent, and the
test data obtained by the Datacolor instrument show the L value of the ultra-black polyester fabrics can reach 9.59.