How Brissett can help

Jul 20, 2008 at 02:48 am by Staff


➤ Brissett Rollers has been a major supplier of printing rollers to the newspaper industry since 1960, keeping pace over the years with industry changes from the old ‘hot metal’ letterpress days to the high-speed offset presses used today. The company’s technical partners include Westland of Germany and Katusra of Japan for printing roller technology, and Contitech of Germany for printing blankets. Brissett has also developed a range of compatible chemistry to suit the rubber components utilised on today’s printing presses. These partnerships enable Brissett to supply rollers and blankets which are the same as original equipment, as well as keeping pace with technological advances. Brissett Rollers is committed to the on-going supply to the newspaper industry as evidenced by further investment in plant and equipment. The company operates two manufacturing sites in Sydney, which ensures continued supply in the event of one plant being closed temporarily. Also, to service all newspaper sites, there are warehouses and offices staffed by local technical representatives in Sydney, Melbourne, Brisbane, Adelaide and Perth. All Brissett sites operate to ISO 90-01/2000 Quality Standards. Brissett Rollers has a strong commitment to education and training. Qualified presenters give on-site seminars – on topics such as rollers, blankets and chemistry – as well as offering tours of the manufacturing plants, popular with production staff. Brissett have taken a very holistic approach to the printing process, realising that all suppliers and customers must work together and not in isolation: “Today’s high-pressure newspaper environment requires more speed than ever before and this, coupled with less maintenance time, lower wastage targets and less labour, puts increasing demands on the supplies used on the press,” says Terry Brissett. “If you look at printing roller rubber technology, the days are well and truly gone where a local roller manufacturer could provide any nitrile rubber and have the roller perform satisfactorily. “Today’s rubber technology is extremely sophisticated. Not only does a roller need to be dimensionally stable, resistant to ink and solvent, with consistent shore hardness, but it is also required to be cool running with an appropriate surface structure to transfer ink and water effectively.” Today’s high speed presses require printing rollers to have superior elastomers in order for the roller to quickly reform after deformation. Rollers which do not reform quickly after the nip point deformation will begin to heat up. As the heat increases, the rubber swells and creates greater pressure at the nip point which in turn heats up even further. Brissett says this process will destroy ink viscosity: “Most cold set inks are manufactured to work at their optimum at 28°C. For every 10°C increase, the viscosity of the ink is halved, causing misting and poor ink and water balance. Surface structure is also important for effective transfer of ink and water. The velvet matt appearance of a new roller is in vast contrast to an old glazed roller. Different types of surface structure and roughness are obtained during the finishing process of roller manufacture. During the transfer of ink, the ‘hills and valleys’ on the surface of the roller flex and transfer ink. If these valleys are full of dried ink, this process can no longer take place. “This is why glazed rollers transfer ink poorly,” he says. “Also if nip settings are too hard, it tends to flatten the ‘hills’ and actually hinders the transfer to ink. Light roller settings are always preferable.” It is not only rollers that have come under increased strain in recent years but also that one point where pressure is literally greatest … the nip where ink image meets paper. And that’s where printing blanket manufactures know they need to perform. “Much is expected,” says Brissett, “and all the basic requirements and fundamental characteristics of a printing blanket need to be satisfied in an uncompromising and rigidly conformist fashion.” Brissett’s relationship with Conti-Air Blanket Technology has seen the Evolution-TR introduced to newspapers around the country. Evolution-TR compressible printing blankets have a ground surface for good ink transfer with uniform printing of solids and neutral paper feed (true rolling concept) in coldset. The slightly more textured surface aids the release and transfer of the inked image from the plate to the paper, and is balanced against the different characteristics needed for optimum halftone quality. Over the last five years, newspaper printers have found the Evolution-TR delivers on high quality and long life: “Image quality is extremely high, even on poor quality newsprint, thanks to the very good surface, low linting capabilities and perfect release,” says Terry Brissett. “On press configurations of all kinds, its construction has been shown to give a long production life. High volume printers report more than 30 million impressions without problems, thanks to the ability of its extraordinarily strong compressible layer to absorb the effects of substantial web-breaks.” Brissett says that because of the company’s strong involvement with the newspaper industry, issues are often brought to their attention for consideration and problem solving. Two examples of this are web creasing and biofilm build up in dampening lines particularly spray bar systems. “We were asked by a number of customers to look for a solution for web creasing,” Brissett says. “Brissett developed a rubber-grooved spreader roller to replace particular path rollers in a web lead. The grooved section of the roller spreads the web from the centre out and has eliminated many of the problems.” Brissett involvement in chemistry and fountain solutions has also focused attention on devices which enhance water quality without the use of chemicals. Brissett utilise the enviro filter pumping system with 5 and 1 micron filtering and a revolutionary ultrasonic system that removes and protects dampening lines from bio-film. Biofilm is a sludge-like film in which bacteria live. “Without the film bacteria cannot thrive,” he says. The film causes huge problems for spray bar dampening systems: The film breaks off from the inside of pipes, and transfers with the flow of water to the spray bar jets. “It can cause hundreds of hours of downtime to clean the jets in a ultrasonic bath,” says Brissett. “Our system sets up an ongoing ultrasonic wave through the press’s plumbing system, removes the biofilm and prevents it from reforming.” Brissett Rollers Pty Ltd NSW – Ph: (02) 9559 3900; Qld – Ph: (07) 3344 4255; SA – Ph: (08) 8340 8699; Vic – Ph: (03) 9587 4111; WA – Ph: (08) 9249 9051 www.brissett.com.au

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