In some examples, a convective gas bar can include a gas inlet to receive supply gas to a first portion of the convective gas bar, feed holes located in the first portion, a nozzle plate located in a second portion of the convective gas bar, where the nozzle plate includes nozzles, and the nozzles are adapted to receive and direct the supply gas from the feed holes through the nozzles.

The invention relates to a drying device (10) for a drying between inking units of a printing machine (1), with which a substrate (2) can be transported via rotating cylinders (3.1, 3.2, 3.3) and is printable with a coloring agent (4), with an air supply unit (11) for supplying of air (5) in direction of the substrate (2) in order to effect a drying of the coloring agent (4), a suction unit (12) for discharging the air (5), a control unit (20), which controls and/or regulates the air supply unit (11) in dependence of the operating parameters (B) in a way that altering drying areas (13.1, 13.2, 13.3) are adjustable at the substrate (2).

A dryer unit (18) for applying a dryer gas to a sheet material inside a printing machine comprises a dryer body (20) having a first set (26) of dryer gas output openings (28). These openings (28) are arranged in a substantially regular pattern covering an application width (20a) of the dryer unit (18). Additionally, at least one dryer gas output slot (38) is arranged upstream the first set (26) of dryer gas output openings (28). Furthermore, a printing machine is presented which comprises such a dryer unit (18).

A dryer unit (18) for applying a dryer gas to a sheet material inside a printing machine comprises a dryer body (20) having a first set (26) of dryer gas output openings (28). These openings (28) are arranged in a substantially regular pattern covering an application width (20a) of the dryer unit (18). Additionally, at least one dryer gas output slot (38) is arranged upstream the first set (26) of dryer gas output openings (28). Furthermore, a printing machine is presented which comprises such a dryer unit (18).

In some examples, a convective gas bar can include a gas inlet to receive supply gas to a first portion of the convective gas bar, feed holes located in the first portion, a nozzle plate located in a second portion of the convective gas bar, where the nozzle plate includes nozzles, and the nozzles are adapted to receive and direct the supply gas from the feed holes through the nozzles.

There is disclosed print agent drying unit 10, 20, 30 to dry print agent 40 on a substrate 14, the drying unit comprising: a substrate support 12 to support a substrate 14; an exciter 18, 28, 38 to excite a boundary layer of print agent 40 applied on the substrate 14, to thereby dissociate the boundary layer from the print agent; and a radiation source 16 to direct radiation energy to the substrate to dry the print agent. Methods of drying print agent 40 on a substrate 14 are also disclosed, including a method comprising: causing the substrate 14 to vibrate to dissociate a boundary layer of print agent 40 on the substrate 14; and heating the print agent 40 to dry the print agent 40.

In a first aspect, the invention concerns a method for providing a varnish coating to individual sheet substrates, said method comprising the steps of applying a liquid coating composition to the upper surface of a sheet substrate, conveying said sheet substrate along a track, while supporting the substrate from its rear surface, and subsequently curing and/or drying said coating composition. In particular, the aforementioned track is at least partly curved. In a second aspect, the invention relates to a device for performing such a method.