Inkjet At a Glance Guide The base technology behind wide format inkjet

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1 The base technology behind wide format inkjet 1. What is inkjet technology? Inkjet technology, literally ink drops jetted onto a substrate, is a non-impact printing method which falls into two main categories: continuous and drop on demand (DOD). Continuous inkjet has the longest pedigree. Although it is fast, the print quality is limited, so it is most often used for date marking and coding. 2. What are the key markets for DOD printing? Current key markets for inkjet technology include display and signage, followed by packaging, labels (barcodes and promotional flashes), fashion and furnishing fabrics, ceramics, interiors and security printing. As it is a non-contact print process, it is also ideal if you are handling unusual or textured materials and want to print on them directly. Inkjet printing can create new markets and change established business structures in some areas. DOD inkjet s speed and quality are already challenging industrial commercial processes. As the trend towards shorter run lengths or variable data applications increases, inkjet printers are providing a flexible and increasingly commercial alternative to traditional offset and screen printing processes. The ability to print on-demand direct from the desktop, without producing intermediate plates and screens, saves valuable time, materials and costs. 3. What is DOD technology and how has it evolved? Piezo drop on demand (DOD) printheads are used for flatbed printing technology and the arrival of DOD inkjet was a technological breakthrough. It can use UV curing, solvent, aqueous, or oil-based inks to achieve very high quality. Piezo printheads can have a long life-expectancy when well-maintained. The achievable jetting speed is lower than continuous inkjet but is increasing all the time with new advances in technology. Originally, machines were four-colour, although extra colours, such as whites and lights, have emerged and future developments depend as much on the ink manufacturers as the machine developers. Inkjet printing today is roughly where the car industry was in Still a very young innovation, the base technology has a long way to go, so for many applications the products are still not appropriate: too expensive, not reliable enough or difficult to use. Most people still use analogue printers but some of these are now being replaced with digital machines which can achieve the speeds and quality necessary to meet some market needs. 4. What will influence DOD inkjet developments? Two base technologies are key to the progress of inkjet printing: printheads and inks. In both areas, progress is rapid. Due to increased demand for DOD inkjet, development of the technology is progressing strongly, which leads to better performance and therefore more demand. It s a continual cycle. Printheads are now able to produce smaller, more regular drops of ink, which allow finer, less grainy images to be printed. At the same time, the density of nozzles per printhead is increasing (making them easier to integrate) and the cost per nozzle is decreasing. All of this is evolving at a rapid rate. UV ink is one of the key facilitators in the development of DOD inkjet as it can be printed on a wide range of substrates. Alternatively, ink for continuous inkjet or solvent inks cannot rise to this challenge. 5. What is UV ink? UV curing inks are designed to change from a liquid to a solid state when polymerisation takes place under ultraviolet light. The UV light initiates a chemical reaction, generating a matrix of cross-linked materials which hardens and dries the ink. This gives the solid ink film chemical resistance, gloss and durability.

2 The base technology behind wide format inkjet 6. Why is UV making strides and what are the main developments? In solvent-based products, the solvent itself helps to control the viscosity of the system. UV ink is 100% solid, which means that no volatile material is incorporated and this makes the viscosity of the ink more difficult to control. However, UV inks offer a wider adhesion range than solvent-based inks, as they can be applied to the broadest range of substrates. They also dry faster without the production of environmentally unfriendly VOC emissions. Aqueous or water-based inks provide a broad colour gamut and vivid colours. However, they can be difficult to control on the surface of some substances and often require specially coated media. There are a number of different types of aqueous ink available, some of which need additional laminating and can fade quite quickly when exposed to light. However, there are now some more durable aqueous inks on the market, which are suitable for outdoor use. UV inks, on the other hand, are known for their high durability and can print on a very wide range of materials, both coated and non-coated. Rarely do they require additional lamination, even for outdoor use. Inks have made steady progress and continue to do so, but the challenges are hard. Chemists are working on formulations that provide better adhesion, more flexibility for post-processing, as well as brighter colour with easier curing.

3 What can wide format inkjet do for your business? 7. Is Inkjet for you? Those only wanting a quick cost cut and an instant financial return could be disappointed. Inkjet machines have a relatively high capital cost, are not high speed compared to other more traditional printing technologies and the consumables do not come cheap. As it is a print on demand solution, users or buyers can gain a cost advantage from the technology as stockholding and waste are reduced. Inkjet provides production flexibility and also gives the user the freedom to handle products that he could not have previously considered printing. 8. How good is inkjet quality? Over the last ten years, printhead technology has progressed considerably. There are now many types of printhead available enabling printers to choose the most suitable type for a particular application and to meet their specific needs. For example, small drop heads can produce a drop size of as little as 10 microns for fine print detail and grayscale heads can produce variable drop sizes down to around 6 microns to give the perception of a higher resolution. Print quality is affected by the size of the drop jetted and the number of nozzles used; the size of the gap between printhead and substrate; the print speed and the stability and accuracy of the motion system. Errors of as little as 10 microns one-eighth of the diameter of a hair can produce visible artefacts. 9. What advantages can inkjet bring? There are a number of advantages that inkjet can bring to your business. It is relatively easy to use, produces high quality results, can handle even very short runs competitively and can help to create new market opportunities. For many users, especially those that started out as traditional screen or offset printers, inkjet can offer a means of increasing sales, creating marketing differentiation, supplying faster response to customers, creating higher product premiums, as well as saving money on stock and the storage of printed materials. 10. What range of substrates can inkjet handle? Inkjet printing puts images onto an incredible number of substrates. The testing and experimentation is on-going as many suppliers are now introducing new substrates specifically designed for UV inkjet printers. Popular substrates include: paper and board, flexible and rigid plastics, glass, metal, and even sheets of steel. Dye sublimation is used instead of UV to print on fabrics and textiles. Aqueous and solvent based solutions are also available, although their substrate range is more limited. 11. I am a Screen/Offset printer what operational and added value commercial benefits will digital printing bring to my business? A digital flatbed printer will add flexibility for short runs and variable data printing, which in turn opens up new applications and new areas of business. With digital printing, the text and graphics in a particular file can be changed with each impression without slowing down production or incurring high pre-press costs, enabling a much higher degree of customisation in the printing process. Printing digitally avoids the need for imprinting variable data, which is a time-consuming and costly process in traditional printing methods. Customers are now demanding shorter and shorter turnaround times on print jobs and with digital, prints can be set up and produced much more quickly than either Screen or Offset printing. Digital printing also cuts down on waste and stockpiling as surplus prints are not required and no sheets need to be printed in the set-up process. Traditional Screen and Offset printing is still the most cost-effective solution for high quality, high volume print jobs. However, by adding a digital printer into the production mix for shorter print runs, screen and offset presses can be utilised more effectively on the longer run lengths and their productivity can be increased.

4 What can wide format inkjet do for your business? 12. What colours can I achieve with a UV inkjet printer? In the early stages of UV inkjet development, most machines simply provided the four process colours; cyan, magenta, yellow and key (black). With this combination delivering only about 80% of the range of pantone colours that can be achieved, progress has been made to increase the number of digital colours available to widen the colour gamut, improve clarity and soften certain tones. The addition of lights, e.g. light cyan and light magenta, gives a smoother appearance to lighter tones, is good for skin tone, and reduces the graininess in lighter colours. In some cases, white is added to the traditional four-colour set in order to give a solid background to products like clear film and coloured plastics and bring out the clarity of colours in the print. If it is a wider colour gamut that is required, orange and violet inks can be added in some instances. These will enable users to hit a wider range of pantone colours, which is especially useful for specific company branding e.g. logos and house colours. Inca s Spyder range of printers have been developed to include six-colour and eight-colour variants, allowing customers to achieve both quality lighter tones and a wide colour gamut if required. With the introduction of the Onset S20 and the more recent Onset S40, customers also have the option of adding light magenta and light cyan to the four-colour set, which ensures that image quality is of a high standard across both dark and light tones. The International Color Consortium (ICC) sets standards to create constant printing quality and consistent colour profiles across all machines. Digital printer manufacturers will run regular tests to ensure that the correct colour profiles are in place and to get the best possible colour matches. The current standard, Fogra 39, is now being achieved by Inca and other digital printers to give customers the standards of colour consistency that they require. 13. What is available to me in the way of prepress and workflow management? Inkjet printers should be supplied with a RIP specifically developed to handle and manipulate files for wide format printing. Inca provides a choice of the Wasatch SoftRIP, ColorGate RIP or Caldera GrandRIP+. These have been tailored to maximise the capabilities of the printer, producing excellent colour accuracy as well as providing colour management tools for every level of expertise. RIPs also provide a level of workflow management and enable you to integrate one or more inkjet printers into your prepress network for centralised control. Inca has recently introduced an optional workflow software component for its printers called Print Run Controller (PRC). This software allows users to print a multi-image, multi-region campaign in a predefined order e.g. by geographic location, by order of priority etc. which further reduces collating times and increases the efficiency of the production. The PRC serves to streamline workflow, thereby simplifying the operator s job and saving on handling and delivery costs. 14. How can I ensure the long life-span of my wideformat printer? Wide-format inkjet printers will last many years provided that they are well-maintained. Inca recommends daily, weekly and monthly maintenance procedures for every machine and these include checking the cleaning station, fluid levels, linear bearings, gantry etc. Carrying out these checks and regularly cleaning the printheads, to remove dust and fibres that affect print quality, will ensure that printer daily uptime is optimised. A good operator is someone who cares about goodhousekeeping and, through meticulous maintenance, safeguards the life of the printheads and machine. Digital is still a relatively new world so someone who loves technology and has an enthusiasm for creating quality in a productive manner is ideal for the job of operator.

5 What to expect from wide format inkjet equipment 15. What is meant by wide format? Wide format is defined by research body IT Strategies as printing at over 24 inches or 2ft wide and wide format inkjet printers can be classified as roll to roll or flatbed. Flatbed inkjet printers can print onto a wide range of substrates, both flexible and rigid, whereas roll to roll work is limited to flexible substrates which often need mounting or other post-printing production processes before being fit for purpose. There are a number of hybrid printers now available which combine roll-fed and flatbed capabilities. These have their limitations, especially in terms of speed and alignment, but are a good compromise for companies that don t have a high volume of flatbed or roll to roll work but want flexibility. Wide format printers can also be categorised by their printhead architecture. Earlier machines printed using a small moving print carriage, whereas some more recent machines, such as the Inca Onset range, have been designed with an almost static full-width print array. Many smaller printing companies still find a smaller print carriage perfectly adequate for their applications and volumes, but larger companies are moving towards equipment with full-width print arrays to increase business opportunities, quality and productivity. 16. What does a full-width print array offer over a smaller print carriage? The most obvious benefit of a full-width print array is its high speed as it can lay down a layer of ink for an entire image in one pass. Smaller print carriages scan across the substrate and build an image up step by step, therefore printing at a much slower speed. Due to the gradual stepping motion of a small carriage, there will often be more textural banding and artefacts in the finished print, whereas a full-width array will produce a smoother print that gives a higher apparent resolution, especially when bi-directional printing. A gloss finish is also much easier to achieve and gloss levels are more controllable with a full-width array compared with a smaller moving carriage. The Inca Onset series of printers are full-width print array machines that offer very high quality prints and exceptional speed. With the Onset machines, UV curing is immediate and textural banding is eliminated. Inca s Spyder printers have a smaller print carriage and are designed with a less complex scanning architecture. Although this means that the print speed is much slower than that of the Onset machines and textural banding can be more of an issue, the ink drop placement is very precise and less colour balancing is required resulting in flatter colours. 17. What machine throughput can I hope for? In wide format printing, there is always a qualityspeed trade off. Speeds achievable on an inkjet printer are dependent on a number of elements e.g. the printhead type and the size of the nozzle. A 10 picolitre nozzle will normally print more slowly than a 30 picolitre nozzle as it creates a finer print grid (addressable resolution). Therefore, even if it is fired at the same rate as the larger nozzle, the overall print time is longer. Slowing down the speed at which the printheads are driven along the substrate can also improve the quality of text and fine details. A faster printhead speed can sometimes result in satellites or tails being seen on close inspection of the print. When choosing the print speed, it is important to consider whether the work is to be viewed closely or at a distance, where the effects are less noticeable. For most printers, throughput is a more useful measure of productivity than speed as it takes into account loading and unloading time, which is an important consideration when running multiple jobs. Inca has continued to develop machines with increasingly impressive throughput and optimal print quality. In 2007, Inca launched the Onset, which was the first machine on the market to have a full-width print array as well as offering automation to increase productivity. This printer set a new record in UV digital flatbed printing, achieving a maximum throughput of 750m2/hr (145 beds/hr). Since then, Inca has continued to develop the Onset series of printers with the addition of the more accessible Onset S20 and Onset S40 models, which achieve superb quality at throughputs of up to 310m2/hr (50 beds/hr) and 470m2/ hr (94 beds/hr) respectively.

6 What to expect from wide format inkjet equipment 18. How much does a wide format digital printer cost and what ROI can I expect? This is complex because clearly there is a wide price spread. Machines can range from about 50,000 to 1.5 million depending on their size and complexity. About 10% of the cost of the machine is usually attributable to printheads. If well maintained, a printhead should last several years. Fujifilm gives the following definition for return on investment (ROI) based on the total revenue of a machine over its lifetime divided by its total cost, but it emphasises that a demonstration and testing are the only ways to verify the true cost justification. ROI = Total Revenue x 100% Total Cost Total Revenue is the anticipated sum of gross invoicing off the equipment over a specified period of time (typically two to five years on digital equipment). Total Cost is the anticipated sum of all overheads, depreciation, operating costs and consumable costs to produce the sellable output off the equipment over the same period of time. The key to calculating an accurate ROI is to have a full understanding of the operating costs. This means you must have an in-depth understanding of: n The real throughput/output capability of the equipment n The actual operating cost of the equipment n The applied cost of ink and consumables n The residual value of the equipment 19. What training, support and advice can I expect with a wide format machine? The supplier should supply on-site training with the sale of a machine. For Inca, that means being on-site for two to five days, depending on the machine type. The level of on-going support and advice will vary but Inca has a dedicated support line responding to technical customer questions. Inca puts emphasis on training and support not only during installation but on an on-going basis. Inca also runs an online User Forum which offers a pool of knowledge and experience. Fujifilm, Inca s distributor, provides ongoing colour profiling and support to its customers as required. Support clearly varies from manufacturer to manufacturer. Inca offers a one year warranty with a machine purchase. It has procedures for good printhead maintenance and recommends regular service intervals under contract. Inca also offers extensive guidance on its website. 20. What post-processing is required to produce the finished product? One of the key advantages of flatbed over roll to roll is that you can print directly onto a rigid substrate, edge to edge if required, with no further cutting, mounting, laminating etc. This not only saves time on each print job but also reduces labour and necessary floor space. Weather-proof UV inks mean that even outdoor hoardings can be ready to display direct from the end of the press. 21. How much ink is used in printing and in the cleaning/spitting/purging process? An Inca machine uses approximately 98% of the ink put into the machine in the printing process. Unlike some manufacturers, Inca machines are not designed to spit or purge to maintain working nozzles in the printheads, so very little ink is wasted. A specially designed chemical solution is used for cleaning the printheads rather than ink.

7 What to expect from wide format inkjet equipment 22. Who are the main equipment suppliers and how do I choose between them? There are now a wide range of inkjet equipment manufacturers, so, when selecting a supplier, it is important to consider the history of the company, its skills and knowledge base, and also its reputation and financial stability. It is advisable to talk to current users of the technology about their experiences. It is essential to find a machine that is suitable for the type and/or amount of work you produce. Be sure to consider output quality, production times, substrate handling ability, cost of production, colour flexibility, operating reliability, set up time and ease of operation. Inca Digital Printers Limited 515 Coldhams Lane, Cambridge CB1 3JS, United Kingdom, T: E: [email protected] It is advisable to take the same test file to each supplier and ask them to print it in front of you at different speeds and in different print modes. The test file should include text, blocks of colour, a colour wheel and images for comparison. Financing a new machine is important so companies need to consider the cost of the machine, the cost of ink in use, maintenance requirements, payback schemes, return on investment, service contracts and response times. Inca Digital January 2012