Printing

During the process of printing on sheet or web of paper and plastics – both often coated, the occurrence of static charge is practically unavoidable (refer to material in Your Problem). Also due to the fact, that the processing speed and cycle times are increasing, a static neutralisation is indispensable in order to guarantee a clean print and enable certain processes with their speed. In the following processes IONTIS products are already used by clients for neutralisation, but sometimes also for systematic charging (adhesive effect):
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Process Electrostatic Solutions
Sheetfed Offset

Generally at feeders the material can get charged, stick to the feeder or interlock, such that double sheet feeding occurs if no static neutralisation is applied. The problem becomes more distinct, the drier the sheet and/or environment are.

At the feed table especially large format and folio-size sheets are vulnerable to re-generating static charge and remain adhered to the table or, feed with mis-alignement in the positioning marks. A static neutralisation needs to be foreseen.

Additionally, in order for the sheets not to float at the delivery and also be stacked precisely aligned, the use of an anti-static bar can neutralise any troubling electrostatic charge.

Serigraphy

Sheet can become charged esp. when printed on plastic or plasticised material. Without static discharge the material can interlock at the feeder and consequently be misfed, stick to the sieve bed and form disturbing paint threads, be attracted when lifting off the sieve and form “crow’s feet”, on the way to the kleben bleiben und Farbfäden ziehen, beim Anheben vom Sieb angezogen werden und Krähenfüsse bilden, adhere on it’s way to the drier or dircetcly to the drier belt and, attract dust from the air.

Web Offset

In the heatset web offset a deliberate charging of the web at the point of feeding the chill/cooling roll will ensure proper web alignment by adhering the web (paper often with 110ºC) to the cooling roll and thus ensure efficient and even cooling without occurrence of stripes of condesnsed moisture.

Rotogravure Printing

To achieve a missing-dot free print quality even at very high web speed, the application of generated static charge to the impression roller can ensure the efficient and precise colour transfer from the paint cups to the substrate even without high pressure on the rollers.

Gravure Printing

Prior and after printing, the occurring static charge cane be neutralised with anti-static bars for the hazardous areas, remove trim waste and dust and reduce potential fire hazard caused by the solvent vapours.

Pad Printing

During the print process, the silicone printing pad can get a strong static charge caused by the inherent continuous deformation and thus generate in turn disturbing paint threads. Ideally, the pad is neutralised either by a anti-static ioniser or an ionising air nozzle.

Wide Format Printing

Static charge on the sheet can make the applied ink generate contortions in the print pattern but also clogg the print nozzles and/or impact the electronic parts of the printing head, if no static neutralisation is performed prior to printing.

Folding

Interlocking of paper strands before the cross-cutter via electrostatic charging can prevent deviations in trimming accuracy and dog-eared sheet corners in the folding machine.

Problems caused in the folding machine at the fin roller through electrostatic charge of the sheets, especially when processing low grammages, leading to congestion and jamming of paper can be avoided through active electrostatic neutralisation.

Packaging

By systematically charging the layers, an interlocking of the stack can be achieved which stabilises later in handling steps between compensating stacker and palletisation.

Pneumatic Transport

Neutralisation via tube ionisation or ring electrode allows for a trouble-free transport of solid parts in tubes with the use of pressurised air (e.g. trim waste and foil remnants at the inlet of cyclones or prior to the mill).

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