Patent ID: 11932004
Assignee: KOENIG & BAUER AG
Field: Textile and paper machines (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A method for ink control in a printing press, comprising, during an ongoing printing process, an opaque ink (02) being printed onto a print substrate (01) in a first printing unit (06), and subsequently a transparent printing ink (03) being printed onto the opaque ink (02) in a second printing unit (07),
a. at least one actual value of the optical density of the opaque ink (02) being ascertained by a first detection device (08), configured as a densitometer, for the opaque ink (02) printed onto the print substrate (01);
b. a film thickness of the opaque ink (02) to be applied onto the print substrate (01) being set at the relevant printing unit (06) by a control unit (11) detecting the at least one actual value of the optical density of the opaque ink (02), as a function of a previously ascertained value of the optical density of the surface of the unprinted print substrate (01), in such a way that the at least one actual value of the optical density of the opaque ink (02) detected by the first detection device (08) corresponds to a target value set at the control unit (11) for the opaque ink (02), taking a tolerance range defined in the control unit (11) for the opaque ink (02) into consideration;
c. at least one actual value of the optical density of the printing ink (03) being ascertained by a second detection device (09), configured as a densitometer, for the printing ink (03) printed onto the previously printed opaque ink (02); and
d. a film thickness of the printing ink (03) to be applied onto the opaque ink (02) being set at the printing unit (07) printing the printing ink (03) by the control unit (11) which also detects the at least one actual value of the optical density of the printing ink (03), as a function of the film thickness of the opaque ink (02) previously applied onto the print substrate (01) or as a function of the actual value of the optical density of the opaque ink (02), in such a way that the at least one actual value of the optical density of the printing ink (03) detected by the second detection device (09) corresponds to a target value set at the control unit (11) for the printing ink (03), taking a tolerance range defined in the control unit (11) for the printing ink (03) into consideration.