Consumables
Trelleborg Provides Unique Range Of Vulcan Offset Blankets At Drupa 2008
Sunday 01. June 2008 - Trelleborg Printing Blankets is one of the worlds leading manufacturers of offset blankets for the graphic arts market and its Vulcan series provides the widest range of solutions for commercial sheet-fed and heatset web offset houses, packaging and carton printers and newspapers. The company also supplies manufacturers of digital presses.
With more than 50 years involvement in producing offset blankets, Trelleborg has a unique understanding of the technology and the complex needs of end users and has also built up during this period a comprehensive global network of distributors. Trelleborg is a participant in PrintCity and is involved in several PrintCity competence centres. It has also provided text for Optimised Sheetfed UV Printing – Best Practice Guide, a major publication that is being launched at the exhibition
Trelleborg invests a significant amount of its resources into R&D, and the company works closely with the industrys major chemical suppliers and press manufacturers to ensure it can provide the right solutions for todays presses and those being developed for the future. Many new presses, from small sheet-fed through to the largest newspaper models, are commissioned with Vulcan blankets.
“The demands placed upon offset blankets become greater every year, with wider and faster presses, new chemicals, the growth of automatic blanket cleaning systems plus environmental issues all having an impact on what printers expect,” says managing director of Trelleborg Printing Blankets, Dario Porta. “Presses have become much more sophisticated in the number of processes they handle in-line, while at the same time everyone is looking to reduce their energy consumption and waste. The blanket plays a vital role in all of these areas.
“The technology involved in the creation of a successful blanket has never been more complex. A blanket has to provide consistent dot reproduction, with good ink transfer on to a wide variety of stock, plus durability and resistance to smashes. Customers expect high quality print almost as a right and this requires the correct blanket on the press, fitted and packed accurately, plus sound technical after-sales support – something that is often lacking from suppliers.
“At Trelleborg we firmly believe in providing customers with advice on choosing the right blanket for the job and ensuring they have a level of technical after-sales support that allows the greatest productivity from their presses. This can include on-site trials and testing at customers premises, plus troubleshooting support and staff training. During drupa we will have blanket experts available on the stand and printers will be able to speak to them about subjects ranging from print problems and environmental issues, to how to pick the correct blanket or even how to use the blanket to reduce power consumption on the press.”
Sheet-Fed Commercial Market
Trelleborg has customers in the sheet-fed commercial market throughout the entire spectrum, from small offset users to companies with long perfectors. The latest Vulcan blanket to be introduced by Trelleborg for the sheet-fed commercial market is Vulcan Coating, which has been developed for printers seeking a highly accurate yet straightforward method of applying spot, knock-out and flood varnish applications on a sheet-fed press.
The new Trelleborg blanket has a polyester base for stability and delivers excellent results with UV and aqueous coatings. The compressible Vulcan Coating blanket is available from 1.96 mm – 2 ply thick and has a maximum linear expansion of 1 per cent. Vulcan Coating can be purchased in a range of press sizes up to 1,433 x 1,890 mm and is specifically designed for offset press coating units.
The unique construction of the new blanket means that it is extremely simple to strip and provides excellent transfer of varnish to the stock. The polyester base eliminates any potential register issues while the stripping layer, which is more than 1 mm thick, means that there is no risk of varnish smudge. Vulcan Coating is suitable for use with cardboard, as well as paper, and is usable in both directions, thereby reducing waste. In addition, the printer can re-use the blanket repeatedly with great precision to handle the same job.
Packaging and Carton Market
Trelleborg offers a wide range of blanket solutions for the packaging, UV, hybrid and specialist print markets, and the company expects its customer base to grow significantly during the next couple of years as these sectors expand. Carton printing is becoming ever more sophisticated as presses are used to apply an increasing variety of inks and foils to the substrate, while developments in blanket solutions have allowed an ever wider range of substrates, such as micro-flute board, to be printed successfully.
“We are extremely careful to produce solutions that printers want, rather than making a product then looking for a market in which to sell it,” says Dario Porta. “The carton and packaging sectors have always been important for us and have traditionally demanded high quality blankets that allow good transfer of ink on to a highly diverse variety of stock, while providing good smash resistance.”
Nearly all blankets come to the end of their usefulness because of physical damage, the most common reason being smashes due to poor quality stock substrate or foreign matter within the board stacks. With a press costing hundreds of thousands of pounds, charged out at two or three hundred pounds an hour, the last thing the printer wants is downtime. Having to stop production to change one, or even more, blanket because of a smash is a costly exercise and can make the difference on the job between loss and profit.
“Compressible blankets dominate the market but those from different manufacturers do not all provide the same resistance to physical damage. In addition, they have to be packed and fitted correctly if theyre going to provide the resistance they are designed to. Putting cheap, poor quality blankets on to any sheet-fed press is a false saving but this is even more significant on carton presses, which tend to be at the top end of investment.
“Trelleborg and its distributors work closely with customers to ensure the printer is obtaining the most from the blankets on the press and this can involve, for example, sending an expert to analyse working practices. We often come across situations where the printer has spent a considerable amount of effort in making sure his CTP, workflows, colour calibration etc are as good as possible, yet make-read times in the pressroom are not as fast as they could be because the blanket has not been incorporated into the evaluation.”
Heatset Web Offset Commercial Market
Trelleborg supplies a comprehensive selection of innovative blanket solutions for the heatset web offset market, including cylindrical, metal-backed, blankets for UV applications and conventional blankets.
The exclusive rubber compound used for the blankets closed cells compressible layer ensures a high smash resistance, good press vibration absorption, excellent print quality and no gear marks. Every element of the blanket is extensively researched and tested. The blanket carcass allows adjustments to be made to the paper feed, according to printing press requirements, while the blankets top surface is micro-buffed to achieve good paper release and print reproduction.
“The increase in material costs and modern web offset press speeds, combined with shorter print runs, makes waste control an ever more important issue for printers,” says Dario Porta. “Vulcan blankets have been designed to reduce waste by ensuring consistent high print quality, easy cleaning and good durability. The high quality fabrics used at every stage of the blankets construction ensure water solvent protection and excellent stability. As with all other Trelleborg blankets, those for the heatset web offset sector use Trelleborgs patented thermo-welding tape to apply bars.”
Newspaper Market
The way in which people access news has changed radically in recent years and the production and content of newspapers has also altered significantly. Trelleborgs long association with this market has allowed it to provide the right blanket solution to meet the industrys differing requirements around the world.
This includes the Vulcan Editor, which incorporates the DynaTech system, a special compressible layer that combines excellent rebound and dampening characteristics that absorb mechanical vibrations. The thicker closed cell compressible layer in this blanket provides an increased smash resistance as well as a longer life span.
One of the biggest changes in the newspaper sector over the last year has been the move to metal-backed blankets and this looks set to increase during 2008. Newspaper printers in France, Germany, Italy and the UK are leading Europe in this area, with around 30 per cent now using metal-backed blankets, a trend that has been fuelled by the installation of presses with 70, 80 and even 96-page capabilities.
“An increasing percentage of newspaper press manufacturers are producing versions with cylinders capable of printing 24-pages in one revolution,” says Dario Porta. “Conventional rubber/fabric blankets cannot be used on these large size cylinders, which can be more than two metres wide, because the gaps created when they are fixed to the cylinders result in unacceptable gear marks and stripes on the paper. Metal-backed blankets overcome this issue and can also cope with the faster running speeds of these presses.”
Despite costing around four times more than traditional blankets, the growing popularity of metal-backed products can be seen as far away as India and Australia. Another major attraction is the ability to replace a damaged metal-backed blanket in around five minutes, a task that could otherwise easily take up to an hour on a newspaper press.