Page 294 - Training 2019

INTRODUCTION:
How can one eliminated dust and dirt in a printing environment that could lead to waste or affect
your print quality? Not only that, but lead to contamination of the product destined for the end
used which could possibly lead to death?

When the customer orders material from his supplier it’s important that the rolls are not
contaminated with dust, fibre from slitting or any foreign objects. This is where static brushes and
tinsel can play a very important part in reducing these problems. Another training session on this
will follow.

When the printer receives the substrate material that needs to be printed on they have very little or
no control of how the stock has being processed before it arrives on his factory floor. During the
supplier’s production process there are several ways that dust and fibre particles can get trapped in
the roll. When the rolls are loaded onto the printers unwind station and the roll starts to turn, static
will be generated at this point. When static is generated it will attract more dust and dirt onto the
substrate. This contamination can be transferred onto your printing plate or blanket in the case of
litho.

The printing plate will be wet with ink and the dirt, dust, lint or whatever contamination that has
come in direct contact with your printing plate will remain there. This will be printed onto the
substrate with every revolution. If the operator does not pick this up it will lead to waste and a very
costly one at that. In litho printing this is referred to as a hickey.

When customers print on foil and films, static plays a bigger roll and dirt on the surface becomes
more critical on these types of materials.

Now this explains all the issues we experience in the print process that leads to poor print quality
and waste. However, after the last print station to the rewind and from slitting to final product to
the customer is another whole ball game. As material moves over rollers there is friction, that leads
to static build up, that will attract any loose dust particles that will be sent to their customer. Now
this might not be an issue in many cases, however if this was the base material for say medical
saline, blood or plasma bags……this could lead to contamination resulting in a whole host of problems.

INFORMATION AND RELEVANCE OF PRODUCT:
Teknek and a host of other manufacturers have developed contact and non-contact cleaning units
that remove all contamination from the substrate before and after the print stations. Today we will
only be dealing with contact web cleaning systems.

A cleaning unit is fitted before the first printing unit. The elastomer rubber roller is made of a special
“tacky” compound that generates static while turning and therefore attracts all loose dust particles
and is in direct contact with the substrate. Then the elastomer rubber roller transfers the
contamination onto the Teknek web cleaner roll which has an adhesive coating, which in fact looks
much like Scapa mounting tape. Once the cleaner roll can no longer pick up dust and lost its
tack……the outer layer is removed exposing a new fresh tacky layer.

WEB CLEANING – TEKNEK CONTACT SYSTEM TRAINING MANUAL 2
Updated - 24 June 2019