PURPOSE: To orderly decorate with a multiform embossed pattern on the surface of a molded plate, by a method wherein a rotary member, which has an embossed pattern surface and turns through the friction force with a molded plate, which is discharged, is mounted at an upper and a lower sides of the mouthpiece of an extrusion molder.

CONSTITUTION: A pair of rolls 3 and 4, around which an endless belt 5 is stretched, and a pair of rolls 3' and 4', about which an endless belt 5' is stretched, are located at an upper and a lower side of a discharge port of a mouthpiece 2 of an extrusion molder. The surfaces of the endless belts 5 and 5' are decorated with an embossed pattern. With molded plates 7 discharged resulting from the extrusion of concrete and other raw materials 8, the endless belts 5 and 5' turn the rolls 3, 4 and the rolls 3' and 4' in synchronism with a discharge speed through the friction force produced between the molded plates 7 and the endless belts 5 and 5', and with this the belts move in a cycle to transfer the embossed pattern to the surface of the molded plate 7.

EFFECT: A molded product has a high size precision and is excellent in a pattern shape-holding property.

USE: Manufacture of building materials.