The latest ink and coating innovations are focused on boosting ink yields and maintain quality results at higher printing speeds, reports Adrian Tippetts.
Stehlin Hostag Ink UK, a division of Huber Group, has improved the performance, quality and strength of its waterbased flexo inks. David Clouston, sales development for liquid inks, commented, ‘The pressure on costs in all business today is more critical than ever. Real partnerships engineering real value are key in the market today.
‘We have in collaboration with Heubach developed a range of high strength concentrates which have delivered cost savings to customers whilst also improving ink quality. The concentrates are the most expensive components of every ink formulation so the ability to reduce the quantity within each formula due to high strength really does deliver cost savings.’
The company has also launched !Check, a web-based management improvement system, through which it claims to have saved its customers £300,000 last year.
Its new solvent-based ink solutions to the market offer printers in the UK a new and exciting option in this market. Currently significant investment and recruitment is taking place to ensure a full portfolio of products and services can be supported.
The next generation of NewV Flexo inks will be launched later this year and will include a new level of low migration solutions for the market.
Packaging printed with Stehlin Hostag Inks
Inks reviewed
After close review of ink and packaging legislation, ColorGen has rationalised its UV flexo offering to three sets. Its TX series (ITX and benzophenone-free) is claimed to be ideal for applications where ink migration is not an issue. The ink maintains good rheology at speeds in excess of 200 m/min.
The company’s TX7 inks have the same chemical make up as the TX series, but are around 30% stronger. These are suited for larger runs as ink consumption can be greatly reduced through lower film weights, reducing the overall job cost.
Use of finer aniloxes also offers benefits in overall print quality when producing fine text and vignettes. The flagship LM7 low migration ink series has enhanced strength to ensure that an absolute minimal ink film can be printed, helping the printer to keep the packaging’s overall migration within limits.
LM7 inks offer good adhesion on a range of papers, boards and films. Recent new developments include a new UV flexo laminating adhesivefor bonding PET to very absorbent board/paper stock.
This is being used in indirect food applications, such as microwaveable lids and packs, conventionally produced by litho or even gravure processes. Producing bespoke low migration inks and adhesives has allowed the changeover to UV flexo.
Other current new developments include a UV flexo opaque primer for metallised synthetic substrates and low odour primers for difficult non-top coated substrates. ColorGen further expects to launch a water-based ink range in the coming weeks.
Brand approval
Paragon Inks has recently announced the global approval and certification of its ULM range of inks and coatings by a leading global flexible packaging converter and brand owner.
Amanda Jones, UK & international sales manager, said, ‘This approval will allow free use of our ULM inks and coatings systems for all primary food contact packaging and product decoration across the globe, giving not only assurance of today’s and future legislation complicacies, but the Paragon One World Product guarantee for ease of cross production across continents.’
The company will be launching its new added value brochure in July, featuring products including Holoemboss and Colorstream, as well as the latest addition to its portfolio, LED ink and coatings ranges for both secondary and primary packaging. These will all feature on the Paragon stand at Labelexpo in September.
New white
Ruco Druckfarben is also gearing up for Labelexpo and promising to be one of the highlights on its stand is a new, ready-to-use 900UV1437 opaque white, which has just been added to its portfolio. This high opacity white can be applied using both UV screen and UV flexo printing, and comes in a low viscosity and silicone-free formulation.
It is highly reactive for good curing and adhesion even at high machine speeds. The ink has excellent flow properties and is suited for overprinting with UV flexo, offset and letterpress inks, making it a good choice for smooth inline production.
Due to its good adhesion to a wide range of different substrates, including polyethylene, polypropylene, polyester and PVC, as well as paper and cardboard, the new opaque white is universally applicable. It is also suited for over-embossing with standard hot embossing films.
A wide range of series 960UV printing lacquers rounds off Ruco’s product range for the label printing industry. Suitable for different application techniques, they help to achieve high resistance to specific media and eye-catching advertising effects.
These lacquers are offered in various formulations – for high gloss and matt finishes, highly media-resistant surfaces, all the way through to special effect lacquers. For example, 960UV451 tactile lacquer is available for haptic effects, and can thus be used for Braille printing as an alternative to embossing.
Optimum cross-linking characteristics of these label printing inks ensure the inter-compatibility of the different inks series. The combination of the new opaque white and 985UV inks as well as 960UV printing lacquers opens up impressive decorative design options for labels, especially for the trendy no-label look.
In the sun
Sun Chemical has launched inks designed to maintain high definition at high speeds and new coatings that provide ways of creating point-of sale impact. Developed for highspeed, wide web flexo presses, the SunSpectro Sunsharp solvent-based inks are high gloss, resistant to water, fats and oils, and formulated for low odour and low viscosity for enhanced colour strength. For printing on polyethylene film, Sun- Spectro Sunsharp HR solvent-based flexo inks provide moderate heat resistance of up to 350 degrees Fahrenheit, maintain excellent gloss and are suitable for use with conventional and high-performance printing plates. Their clean printing and water resistance make them suited for printing on items such as plastic bags, shampoo bottles and milk containers. The SunBar Oxygen Barrier Coatings are designed to enable lightweighting of packaging by removing the metal foil and one layer of adhesive from packaging, as well as offering improved laminate flexibility. A smooth, homogenous, pinhole-free layer, it can be overprinted with inks and laminated to a variety of secondary films.
Software and logistics
Like all oil-based raw materials, inks have been subject to significant fluctuations in the last five years. The trend towards shorter runs and raw material price volatility means printers must put more focus on cost control and look for ways to drive waste out of the workflow. The key to reducing ink waste is to produce the exact volume and quality requirements without over-production or remakes.
There are three components to controlled ink logistics. The dispensing system provides fast dosages of ink or coating, software provides cost and stock control, and proofing systems ensure perfect colour is achieved as fast as possible. A major supplier of ink logistics solutions is GSE Dispensing with its Colorsat range of ink dispensing systems. Automatic ink dispensing systems – gravimetric for spot colour recipes and volumetric for process colours – dispense the exact requirements within a few minutes.
Dispensing systems can improve yields by up to 30%. As well as calculating ink recipe requirements to within 1 g accuracy, the systems calculate excess ‘press return’ inks into new recipes. A range of dispensing systems is available, adapted for ink quantity or ink set requirements.
Cartridge-holding dispensers catering for up to 5 kg (11 lbs) batchesare suited for label printing runs, while systems for flexible packaging or corrugated board may dispense up to 600 kg (1300 lbs) ink.
Ink management software can now be integrated into the corporate IT workflow, allowing easier colour formulation, job database management, recipe recall, job cost analysis, real-time stock availability and traceability of ink batches. GSE’s Ink Management Software (IMS) allows the printer to store a database of commonly used recipes. Standard integration with an MIS package provides the production manager real-time information about recipe availability, enabling quick response printing. The integration with MIS also allows detailed ink cost-analysis of each order, and the ability to trace inks used on every job to the original base ink batch number. This substantially saves operator time.
The third means of controlling ink use is the table top proofer, which provides precise flexo colour predictability offline, without the need for fingerprinting. With a photopolymer proofing head, the proofer provides a perfect miniaturised simulation of the conditions of the target flexo press. That way the unit can proof halftones and replicate the exact dot gain of a particular station and produce halftone proofs that mirror what will come of the target press. It eliminates the need to make colour adjustments on the press, reducing up to 15 minutes of set-up time per job.
Maarten Hummelen, marketing director, said, ‘Major brand owners demand exacting standards from print suppliers in order to achieve high visual impact on the retail shelf and an identical look and feel wherever their brand is sold. Increasingly, therefore, printers must supply unique colours with predictable results. Dispensing, proofing and software systems provide the framework to meet these expectations, while maintaining a lean, waste-free ink workflow.’
