What is the connection between the lotus flower & Westland Gummiwerke GmbH? A great deal, because the way water rolls off a lotus leaf forms the fundamental principle of a new development named LotoTec, this is a new patented roller coating that is hydrophobic in the same way that Teflon is but still suitable for use as a damping roller, perversely, it quite deliberately exploits this apparent contradiction, the fact that Teflon is water repellent and will offer the printer important benefits.
The LotoTec roller which is a new development of the already tried and tested Werodamp roller has been developed by German-based Westland Gummiwerke, one of the world’s leading roller manufacturers.
LotoTec is set apart from other traditional elastomer rollers by its unique fluorinated elastomer coating which gives three significant properties. Firstly the material gives very low surface tension, giving the rollers exceptional wetting behaviour ‘similar to Teflon’. Secondly fluorinated elastomers are high performance polymers which give increased chemical, oxidation, ageing, extraction and temperature resistance. Thirdly the surface roughness is dramatically lower than that of a traditional polished roller, this is due to the method of application used, whereby the fluorinated elastomer is sprayed on and dries to form cross-links, giving a glossy, smooth surface.
The exceptional wetting behavior means less water is required to achieve ‘clean running’ and less water runs back up the ink train, in consequence the ink emulsion is consistent and stable, proving more resistant to repeat ghosting or tracking, as well as proving secure against over-emulsifying and ink fly, also the ink film is brighter and dries faster and the printing window is wider. In addition the hydrophobic properties of the LotoTec surface help to eliminate the cording effect seen on some press types.
Perhaps the most important aspect of LotoTec is it’s compatibility with IPA-free printing, which it is able to do with its direct generation of a very smooth damping film.
Printers will also be pleased to know that due to their ‘Teflon-like behaviour’, LotoTec rollers are incredibly easy to clean, taking just seconds, which is a welcome relief to anyone with an eight colour press, the less time that is spent cleaning gives more time that the press is printing. Furthermore less cleaning means less use of organic solvents and cleaning materials.
Westland Rollers are distributed and manufactured under-licence by BFS Pressroom Solutions in the UK.