Coating and laminating in the spotlight
Pushing the boundaries
Through intensive R&D work on its own production scale, high speed Technicum machines, Kroenert claims to be “opening up completely new performance ranges for coaters and laminators”.
The company’s MPG 600 CI reverse gravure pressurized chamber doctor blade coating system is used to apply aqueous and solvent based primers and top coats to metallized paper at 1,000m/min. Wet laminations of six micron aluminium foil to paper up to 25g/m2 for cigarette pack inner liner are also carried out at the same rate.
And a new hotmelt machine is said to have proven that even coating jobs that previously could only be executed at up to 600m/min can now be accomplished on production machines – in-line with siliconization – at 1,000m/min.
Kroenert is also heavily involved in the new coating and lamination processes for the growth markets in smart cards and labels, as well as in bank notes and medical packaging. This requires machines with the highest precision as well as a coating process under cleanroom conditions and an inert gas drying process.
More information from Michael Schmalz, Maschinenfabrik Max Kroenert – TEL: +49 40 8539301. EMAIL: email@example.com
Coatweight consistency controlled
The NDC Infrared Engineering 5203TC-4 on-line measurement system being used by flexible packaging supplier Perfecseal is said to have reduced variations in adhesive coatweight significantly. It provides closed loop control, so coating thickness can be adjusted accurately and quickly to maintain product quality and consistency.
“Previously, coatweight checking was done manually,” confirms Northern Ireland based Perfecseal’s John Muir. “Adding the 5203TC-4 system has made an immediate impact on the quality of our products. It has performed well, with a dramatic improvement in coating quality.”
The NDC Infrared system has four sensors mounted by the web to provide continuous measurement and display of the coating weight. A high resolution colour CRT with touchscreen interface continuously displays base, total and net coatweight in real-time whilst allowing the operator to alternate between display screens.
More information from Dr Ian B Benson, NDC Infrared – TEL: +44 (0)1621 852244. EMAIL: ibenson@ ndcinfrared.com WEBSITE: www.ndcinfrared.com
Measuring the ‘unmeasureable’
The ScalarGauge range is being used to measure coating thickness below 5nm – on-line and in real-time for high quality security coatings running at 400m/min. The outputs from the gauges are then fed back into the automatic control systems to ensure optimum production parameters are maintained.
Scalar Technologies says its systems are controlling processes “which up to now have been unmeasureable”. A typical example is at Autotype International, of Wantage, UK, whose ultra thin technical coatings for the membrane industry cannot be measured with conventional technologies. The ScalarGauge is said to provide accurate measurement and allow the process to be controlled to a much higher level.
The ScalarGauge system using white light interfer-ometry is claimed to measure both on and off-line with a flexibility that allows a wide range of coatings and laminates to be measured down to 0.3 micron. Its ability to measure multi layers is said to be ideal for laminating and co-extrusion work.
More information from John Cranston, Scalar Technologies – TEL: +44 (0)1506 414806. EMAIL: firstname.lastname@example.org
From trolleys to twins
According to Italian manufacturer Uteco, the use of trolley type coating units has certain disadvantages. “For example,” explains Alan Attard, of UK agent Eurograv, “because of usual machine width, trolleys can be difficult to move and may lose their precision by being bumped or knocked. The coating unit needs to be cleaned, often causing additional downtime, and if a mechanical or electrical problem arises on the coating unit, more machine downtime occurs.”
As an alternative, Uteco is offering a machine with a double coating unit, completely enclosed and with exactly the same drive and components. While one unit is engaged, the operator can prepare the second, with no downtime.
This concept has been introduced on a multistation coater/laminator now running pressure sensitive adhesive coatings on widths from 1,600-2,200mm. In this application, light trolleys are used to move single units such as rolls and coating pans. When the job requirements change, additional components can be added or items removed, even while the machine is running. “The big advantage,” says Alan Attard, “is that if a problem occurs with one coating unit, the machine still continues to meet production targets with the other.”
The Uteco machine has a working speed of 300m/min and is equipped with a fully automatic turret unwinder with tension control and pre-conditioner for BOPP film. It has a silicone release station with possibility of UV or water based application, and dual coating units for single roll with Meyer bar, reverse, offset gravure, and three-roll reverse coating.
More information from Alan Attard, Eurograv – EMAIL: Eurograv email@example.com WEBSITE: www.uteco.com
A 1,300mm width high specification foam laminator has been supplied by Elite Cameron to self adhesive tape manufacturer Alfas Adhesives, in Newcastle upon Tyne, UK.
As Alfas may change the type of tape as many as 15 times in a shift, reduced downtime between runs was a priority. So the machine was designed with two dual unwinds to facilitate loading of the next reel while it is running.
A special automated, cantilevered loading post delivers the reels to the relevant unwind at the touch of a button, eliminating all shaft handling. The machine can produce double-sided laminates in one pass, with the facility to remove one liner in line for self wound products.
Another recent sale was an HM1000 hot melt coater to Ryco, in Ireland. The machine will coat up to 1,250mm full web or stripe coat for tape applications. Using the latest Valco slot die technology with full touchscreen and integrated coat weight control, it is designed for one-man operation, and for rapid changing of coat weights and width.
More information from Tim Self, Elite Cameron – TEL: +44 (0)1823 283411. EMAIL: firstname.lastname@example.org
Smaller EB units aimed at flexibles market
Energy Sciences has introduced a smaller, cheaper version of its electron beam curing equipment, to cure coatings and adhesive laminations for the mid-web markets. EB is already established in the carton industry in North America, as an economical alternative to UV varnishing.
UK agent Edlon’s Lawrence Wild says the new EZCure 2 equipment has been developed to “open the doors” to converters who want the benefits of EB but could not use it because of the size and cost limitations of previous machines. “One of the key restrictions of the EZCure 1 range was size,” he says. “A 50 per cent reduction in the in-line space requirement of the new equipment makes it more adaptable. It also requires almost 40 per cent less power to operate, and addresses the capital cost issue. For a typical 1,350mm wide unit, there is a price reduction of about 15 per cent.”
According to Energy Sciences, the major potential market for low voltage EB equipment is flexible packaging, especially for EB coatings replacing laminations or other coatings, and EB curable laminating adhesives replacing conventional laminating adhesives.
More information from Lawrence Wild, Edlon Machinery – TEL: +44 (0)1707 827957.
US company Capacitec has developed the use of capacitive non contact thin gap sensors to control coater die slot gap uniformity. The company claims dramatic improvements over traditional methods, achieving coater gap uniformity better than 0.25 micron across the full length of the die. In fact, according to Capacitec, in some applications it has been exceeded with uniformity being maintained at levels down to 127nm.
Measurement of thinner gaps down to 0.125 micron is now under development.
More information from Tony Hale, Powertronic Sensors – TEL: +1 978 772 6033 EMAIL: email@example.com
Valmet Rotomec offers customized duplex and triplex laminators, as well as coaters and extrusion coating lines.
The Rotomec SL/SB combined coater/laminator has a cartridge type coating unit, a five-roller system for solventless adhesive, and a gravure system for solvent based adhesives. Handling web widths of 1,200-1,400mm at up to 330m/min, it has a five metre, two-zone dryer and a corona treater.
More information from Steve Brimble, Valmet Converting – TEL.: +44 (0)1767 310100 . EMAIL:firstname.lastname@example.org