Surface decoration method and apparatus for decorating a printing substrate made of ceramic material

A surface decoration method to create a defined decoration on a printing substrate made of a ceramic material;

• the decoration method comprises:
• a conveying step, during which a conveyor assembly conveys at least one printing substrate along a given path, in a conveying direction, through at least a first printing station, at least a second printing station, which is arranged downstream of the first printing station along the given path, and an inspection station, which is arranged upstream of said second printing station along the given path;
• a first printing step, during which a first printing system, which is arranged at said first printing station, creates a first pattern on said printing substrate, while the latter advances at the first printing station;
• an inspection step, which is at least partially subsequent to said first printing step and during which an inspection system, which is arranged at said inspection station, acquires at least an image of said first pattern created on said printing substrate and estimates data on the position and the orientation of said first pattern;
• at least a second printing step, which is at least partially subsequent to said inspection step and during which a second printing system, which is arranged at said second printing station, creates a second manipulated pattern on said printing substrate;
• and
• a controlling step, which is at least partially subsequent to said inspection step and simultaneous with said second printing step and during which the control unit controls the activation of said second printing system based on the position and orientation data of said first pattern, so that said second printing system creates, on said printing substrate, said second manipulated pattern in order to define, at least together with the first pattern, said defined decoration;
• wherein, during said inspection step, said inspection system determines the coordinates of said first pattern created on said printing substrate with respect to a fixed reference system which is integral with said inspection system and the orientation of said first pattern with respect to said conveying direction with an accuracy of at least about ±0.6 mm for the coordinates and ±0.1° for said orientation.