Tag Archives: flexography

How to Supercharge Your Water-Based Flexo Inks

Apex International Blog

by Jeanine Graat, Apex International

Global Environmental awareness is driving the printing industry to consider other ink systems in order to print more ecological packaging. Water-based inks are often praised as the green solution for a more sustainable product. They are a comparatively eco-friendly product, but when it comes to printing inks on to films and plastics, water creates problems

  1. Unless we print on high absorbency substrates, water inks require significant heat to dry and to leave a cured ink film on the substrate. In other words, they require energy that negates any positive ecological benefits from the use of water-based inks.
  2. Water has a high surface tension, which can print beautiful perfect dots however creates mottled/pinholed solids, which means that in order to ‘wet out’ on most plastic surfaces, the surface tension has to be reduced considerably in order to achieve good print quality and smooth laydown of ink.
    That is done by adding a surfactant or a solvent, which contaminates the water immediately. Depending on the substrate, the type of press, the printing speed, the amount of solvent can range between 2 – 20% of the press-ready ink.
  3. Waterbased ink is also susceptible to foaming creating micro bumbles which thickens the ink and creates a reduced ink transfer. In order to solve this, the ink can be adjusted with anti-foam agents which in turn create drying issues and trapping problems.
  4. Water has to be combined with solvents in order to dissolve the kinds of resins that provide good adhesion on packaging films. Read: more chemicals!
  5. Switching from a solvent based ink to a water based ink cannot be done overnight, because of the different transferring capabilities. It often means modification to the anilox rolls because a shallower, more open cell structure is required to print water based inks.
  6. Contamination between solvent inks and waterbased inks creates an adversus chemical reaction that can result in the ink setting solid and then a major cleaning of anilox, pumps, pipes is required. Therefore, a press is required to be dedicated to waterbased inks to ensure press efficiency is maintained and waterbased ink print is viable.

How to Supercharge Your Water-Based Flexo Inks

Having touched on the characteristics of water based inks here above, it cannot be left unmentioned, that critics have doubts on the printability of water based inks as well. They appear to result in:

  1. Poor scratch and rub resistance (especially shortly after printing)
  2. More difficult to re-wet
  3. More difficult to clean
  4. Comparatively lower gloss and poorer color strength
  5. Ink sets onto the plates creating ink build up and an inconsistent print
  6. Slow drying and therefore more heat/energy required
  7. Highest risk of clogging inside the anilox cells (especially with low-volume anilox rolls)
  8. Very difficult to control and guarantee a consistent and repeatable ink transfer (because of the pH and viscosity)

Water based inks – the future of printing!

Still, ink suppliers and also machine manufacturers dare to announce that water based inks are the future of printing. And a major part of the success of printing water based inks, lies in the actual transfer of the ink. Many of the above print issues can easily be solved when the right configurated anilox roll is used.

Apex International have performed several successful trials together with different ink brands in combination with leading machine manufacturers. The results reported by the ink manufacturers was:

  • The shallow surface structure of the open-slalom laser engraving technology developed by Apex, results in no clogging. The most effective ink transfer allowing for the maximum ink replenishment within the Anilox surface compared to the restricted limits of any conventional engraving is realized. A very thin layer of ink can be transferred and less drying time is needed (energy savings!).


  • Major advantages with no air inside the print process. In a closed-cell structure (image left), air gets trapped inside the cells and especially with waterbased inks, that is a disastrous combination. With the open-slalom structure (image right), the ink flows freely and the air will not get stuck inside the cell, it simply flows away. Less air simply means a better lay down of ink and better results on gloss and color strength. A side effect of having no air inside the print process, is the fact that a defoamer is no longer needed, which makes water-based printing an even more ‘green’ way of printing packages.

How to Supercharge Your Water-Based Flexo Ink  How to Supercharge Your Water-Based Flexo Ink

  • With an open structure, the phenomen Dot Dipping does not occur. The explanation is simple: pressure causes counter-pressure, ink escapes through the opening and the result is over-inking. The water-based ink does not set onto the plates and will not cause ink build up and therefore inconsistent print is no longer an issue. The below image shows this:

How to Supercharge Your Water-Based Flexo Inks

  • The key to the success of waterbased inks is to control the viscosity and the pH and the key benefit of the open-slalom surface structure is a consistent ink transfer and the ability to print repeatable results with no air inside.

Conclusion: the last 5 print issues (out of the 8 mentioned) caused by waterbased inks, can be improved by using Apex GTT Anilox technology, which is a very good step in the right direction of a greener Flexo future.

Samples of waterbased prints performed by different ink brands on 3 different machine types will be available in the ‘Green – Waterbased Area’ at the Apex stand (11B26). Receiving your samples by visiting theDrupa stand, or by requesting your sample pack here.

See physical proof of state-of-the art ink-transfer technologies that obviously supercharge your water based inks!

Reserve your FREE Sample Pack!

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Troubleshooting Part 2: Coating/Laminating

Troubleshooting: Coating & LaminatingBy Tom Kerchiss, RK Print Coat Instruments Ltd

Co-operation and shared goal setting has become increasingly prevalent in label and package printing and converting as all supply chain providers and operatives strive to meet benchmark standards while endeavoring to make a profit. Regardless of whether the process step that you are engaged in is printing at the start of a run or it’s a converting process at the end of a run it is in every one’s interest that process variables and what causes them are understood and that inconsistencies are bought under control in the shortest possible time, with minimum inconvenience and with as little waste generated as possible.

It goes without saying that process quality is only as strong as its weakest link. For example, if print is of the highest quality this will count for nothing if a subsequent coating process, slitting or rewinding goes awry. Apart from product throwaway the printer will have wasted time, energy and material turning out a product with value only to see it scrapped.

When it comes to print processes such as flexography there are devices now such as the FlexiProof for identifying, resolving and controlling ink variables; for colour matching and determining printability: gloss, durability, rub resistance, etc. Other devices, such as the hand held portable trouble shooting device, the EsiProof were covered earlier in an editorial entitled Part 1 of Troubleshooting.

Coating and laminating are process areas that are theoretically straight forward but are becoming more complex as time goes on. Coating and laminating has its own set of challenges, some of which the coating technologist seemingly has little control over.


The substrate onto which the coating is applied is often responsible for a range of defects inclduing: poor adhesion, poor planarity and lay-flat. Substrate associated issues of note include winding irregularities as well as the defects that arise as a result of airborne and other forms of contamination. These defects can occur during substrate manufacture, product shipment and storage and during on machine processing including, when the product is being fed through the machine or on being unwound and rewound. In many instances the problem is exacebated by the presence and generation of electrostatic forces. Even the operator may introduce contaminants such as skin, hair and fibre from apparel.

An inability to coat a substrate uniformily or to wet the substrate effectively warrants mention. In order to deposit a fast flowing fluid coating onto a given substrate with no voids or inconsistencies its necessary that the surface tension of the coating solution and the substrate surface interface optimally.

To achieve the best of surface conditions it may be necessary for the surface to undergo modification via flame/electrical discharge or plasma treatment. Another approach is one taken by the manufacturing chemist whereby surface tension characteristics are measured and the formulae is manipulated within specific parameters.

As with many of the problems that arise during processing, regardless of whether its flexo printing, slitting, coating or laminating there is rarely a clear cut solution, its often a case of eliminating possible causes one by one. Coating uniformity or lack of it can sometimes be due to substrate manufacturing variability or an innapropriate choice of coating applicator. For instance, variation in the thickness in a non-transverse direction can, particularly if knife coating is the selected applicator method affect coat uniformity. The reason that knife coating technology is susceptible to substrate variation is that the blade is set at a fixed height and therefore substrate/coat contact interface is critical.

Staying with knife coating for the moment its worth noting that the way in which an air knife coating is applied can produce some unexpected results. When a coating is deposited on a web at high speed the flow of fluid is subject to an alternating flow regime. All laminar flows on a moving web have a parabolic velocity profile with the fluid at the surface of the web moving at the speed of the web. The fluid at the air interface however, behaves differently and is just a bit slower than the speed of the actual web. In effect the volume flow up exceeds the volume flow down.

With regard to air knife coating the thicker flow builds up just below the air impingement zone or meniscus. Once the air knife allows the thinner coating flow to pass, any excess liquid collects below the meniscus and will not flow on until the lower layer builds up and becomes thick enough to balance the upward shear force that derives from the web. This ebbing and flowing produces tiny fluctuations in the flow of coating just above the air knife which can result in the coating looking flawed. Sometimes the coating fluid smooths down and has a desirable varnish or enamel looking finish. Sometimes it does not smooth down and the coating shows signs of chatter or streaking. If this occurs the coating operative has little choice but to experiment, find an appropriate suficant, one that will promote post coat smoothing without jeapordising wetting or adhesion properties.


Laminating throws up its own share of problems. Sometimes when a two ply dry bonded laminate comes off the machine it has a hazy appearance. This often perplexes everyone, especially when the job has been run previously without any problems using the same substrate and adhesive. In reality the clue to what’s causing the problem is in the hazy appearance. If too little adhesive is applied to the primary substrate high and low spots willl allow air bubbles to develop and with it the hazy appearance. If the adhesive coat weight is increased the haziness should disappear.

As with most processing functions attention to detail pays off. For example coatings and primers must be dried properly. Lets consider an out of line heat seal coating application as an example.

This heat seal coating is applied to foil for the purpose of providing adhesion to polyester. The heat seal coating is deposited on one side of the foil. This coated foil travels through an oven and the dried coated foil is wound up in rolls. The rolls are then stored until they are needed. The roll is unwound and combined with the polyester by passing the two substrates through a heated nip to effect the bond. The material is then rewound with the foil/heat seal coating/polyester ready for shipment to the customer.

Any coating or primer must be dried completely. If not the material could become tacky and when wound up in on itself the material will adhere to the backside making subsequent unwinding impossible

Good housekeeping is a must. The flow rate to roll coating pans should be monitored and adjusted; solution and applicator temperatures must also be watched and the gap between applicator and coating roll measured with substrate in place. Consideration must be given to the correct coating applicator. A slot die applicator may well give good results when used with a closed surface substrate such as polyethylene as the fluid will not penetrate and will be uniform. However the same applicator if used on a substrate with an open porous surface would produce a less uniform result as some of the fluid will penetrate into the pores. In this instance a knife coater would be the best option because as the blade is fixed at a set height from the web there will be uniformity of coating fluid and the pores or cells of the substrate will be filled.

Coating viability depends to a large extent on selecting the most appropriate coating method for a product to be processed – not always easy. The coating operative must take into account product function, desired coating weight, quality level needed, raw materials required, and of course the material onto which the coating is to be applied needs to be considered. There is a wide range of pre and post metered coating technologies that can be used. But which one will give the best reproducible quality? Sometimes its trial and error to determine which technology to use and this is especially true when it comes to developing new products.

The Rotary Koater

The Rotary Koater, a pilot printing, coating and laminating system designed and developed by RK Print Coat Instruments is an ideal system for those faced with daily coating/laminating challenges. As a research and development tool it enables the manufacturer, the printer, the converter and others, to undertake R & D on an economical scale and under precisely controlled conditions. It can be used to test different formulations, substrates and processes. It is also highly effective as production machine for the small-scale production of specialized materials.

On the other hand there are those organizations that for one reason or another need specialized machines; a standard machine simply won’t suffice. The VCM or Versatile Converting Machine meets the needs of this niche market.

Each VCM is purpose built and unique to each customer. A precision system, each is built under conditions of close commercial security. Customers are able to select from best available technology including 15 different printing/coating technologies.


RK Print Coat Instruments Ltd
Litlington, Royston, Hertfordshire SG8 0QZ
www.rkprint.com sales@rkprint.com

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Filed under Printing, Troubleshooting

Top Causes of Anilox Scoring and How to Prevent Them


by Doug Jones

A score line in an anilox roll is a groove that has run directly through the engraved surface.  The score shows a visible line in the printed or coated product and is irreversible. Once the surface is scored, the roll must be reconditioned or replaced. For these reasons, it is crucial to learn how to prevent scoring whenever possible. Below you will find an explanation on score lines, the different types and how to prevent them from occurring and keeping your print quality as high and consistent as possible.

3 types of score lines:

  • Cosmetic or Preliminary
  • Lightly Polished
  • Severe or deeply gouged

Anliox Scoring - Score lines

Anliox Scoring - Samples of score lines on different substrates

Samples of score lines on different substrates

What Causes Anilox Scoring?

Over Impression

Over impression can cause premature wear to the doctor blade and roll. Long Blade tip slivers can easily cause score lines: these are formed when the blade bends back causing wear on the side rather than the tip.  As the side of the blade wears through, the tip breaks away in the form of a long metal sliver.  Normal shavings from blade wear from “kiss impression” will not damage a roll.

Doctor Blade Tip Material & Settings

Are you using the same blade for whites or metallic inks as you do for conventional ink? Using incorrect blade tip and material for type of ink can have disastrous results and hardened blades significantly increase the chance of scoring.  The same can be said of replacing the blade on every anilox change.  A blade “seats” to a specific LPI and is not meant to be used again.  Blade forms to anilox and becomes a “Micro” saw.  Finally, try resetting the doctor blade chamber after installing new blades.  A worn blade is shorter than a new blade and if chamber does not reset, there will be excessive pressure.

Try a nickel coated anti-scoring blade. Nickel is softer than steel and ceramic, many converters use this very successfully as it is more forgiving and can cover potential misgivings in the metering process. It will also last longer because of coating; cleaner doctoring because blade is stronger; resist corrosion better because the blade has a barrier coating.  And remember, always use higher quality blades. A low quality low cost blade can break down fast.

Anliox Scoring

Helpful Hints

  1. Coated blades are more forgiving than uncoated blades.
  2. The doctor blades should never extend past the ends of the seals, but should be flush and even with the bevels on the end seal.
  3. A coated blade will offer more “forgiveness” than an uncoated doctor blade and compensate for error
  4. Chattering blades vibrate and this action can act like a jack hammer to the ceramic and break cell walls
  5. If too soft, improper end seals will cause leakage and operator might adjust setting to compensate putting more pressure on anilox and stress on the blades. Do not set chamber to stop leaking.
  6. Correct placement of end seals allowing even contact with anilox and consistent transfer of the ink film to plat
  7. Shims break off or can become exposed to the anilox surface and cause scoring
  8. Ink resins can glue pigments, blade metal and other debris to the blade

Get the flexo solutions guide now!

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Imaging the Possibilities


by Catherine Green, All Printing Resources

Exploring Today’s Plate Imaging Options
A common fear among those still using film imagesetters to produce photopolymer plates is that their device is on its last days–barely hanging on to operational status. Replacement parts are few and far between, leaving little choice but to scour the Internet for parts and redundant equipment to keep the imagesetter operational. In a recent survey, some imagesetter users reported expenses of up to $9,000 annually for parts and services. It also represents taking the risk that the imagesetter can be repaired in a timely fashion (or at all) to avoid costly downtime. The purpose of this article is to present options available to satisfy nearly every budget and quality requirement.

Choosing an imaging system that fits your needs is critical to a successful return on investment. Not only should the current requirements be considered, but perhaps more importantly future needs and objectives.

  • What are the objectives of your company in the next five years?
  • What level of quality will your customers demand, and what will your competitors have to offer?
  • How many finished plates per hour or shift need to be completed?
  • What are your typical and maximum finished plate sizes?

Before selecting an imaging device, knowing the answers to these questions will ensure that this important asset will fit your needs for many years to come.

Eliminating Film: A Streamlined Platemaking Workflow
For those seeking a way to eliminate film from the platemaking process, there are several options. Direct engraving, laser ablation, and inkjet CtP are all filmless plate imaging options. While all three methods yield an imaged flexo plate, there are considerations for each method that can make or break these technologies as a fit for your business.

Laser Ablation
By far the most popular digital platemaking option, laser ablation devices use a YAG fiber or diode laser to ablate image areas on digital flexo plates (plates with a black carbon LAMS layer). Ablation refers to the process of the laser beam(s) vaporizing the black carbon layer, exposing the plate material beneath. This allows the ablated areas of the plate to be exposed to UVA light and cure, forming the printing image. Specially engineered ablative films can also be imaged by this type of device to produce positives or negatives for applications requiring film. Laser ablation devices are the current industry standard for digital platemaking for a number of reasons including high quality output, wide selection of compatible plate materials, and overall efficiency.

Laser Ablation Pros:

  • Efficient throughput of plates.
  • High resolution imaging capabilities and specialty screening options.
  • Small overall footprint with minimal auxiliary equipment.
  • Excellent reliability and ease of use.
  • Seamless imaging capability (with Esko CDI Cantilever and ITR plate sleeves).

Laser Ablation Cons:

  • Initial cost of equipment can be a large expense.

The largest and leading supplier of laser ablation devices is Esko. Esko is a global supplier of integrated solutions for the packaging and labels, sign and display, commercial printing and publishing industries. Esko has been developing software and hardware innovations for packaging and printing for decades. The company invented digital flexo in 1995 and has been leading the development ever since. Esko’s flexographic solutions are used in about 90% of high quality flexo production. Today, Esko is synonymous with excellent quality and consistency in all flexo printing applications.

Another global supplier of laser ablation plate imaging devices is Xeikon. Formerly known as FlexoLaser, Xeikon’s ThermoFlexX devices also utilize a YAG laser for ablating plates. In December 2015, Flint Group acquired Xeikon to expand their reach into the digital printing market, forming a new division called Flint Group Digital Printing Solutions.

Inkjet Computer-to-Plate
As a newer technology in the plate imaging market, Inkjet CtP eliminates film from the platemaking process by utilizing inkjet technology to print a mask layer onto analog sheet photopolymer. The process is simple, fast, and the equipment is the least expensive of the digital plate imaging options. While overall image quality is not on par with laser ablation, this option would be suitable for narrow web printers who can work with the small plate size requirement and are not planning to implement high resolution/high LPI printing techniques.
DigiFlex is the exclusive manufacturer of the FlexoJet 1725 Inkjet CtP device for flexographic plates. Their unique bi-component ink and laminated primer system make this device compatible with nearly any analog plate on the market. Uniquely, the Aquaflex Optima plate does not require the laminated primer to be applied, resulting in a streamlined workflow and consumable savings.

Inkjet CtP Pros:

  • Small device footprint.
  • Quiet operation, even suitable for office environments.
  • Can utilize same analog material through transition to digital imaging.
  • Flat top dot is produced when primer is applied.

Inkjet CtP Cons:

  • Imaging resolution is lower than laser ablation.
  • Periodic manual cleaning is required.
  • Ink and laminate consumables required for operation.
  • Printed mask must be removed with water before solvent processing.
  • Limitation on the size of the plate that can be produced.

Figure A – Comparing Laser Ablation to Inkjet CtP Plate Imaging


Direct Engraving

Direct engraving machines image plate materials using a high-powered engraving laser. The laser destroys the non-image areas of the plate to create relief. These machines eliminate film as well as traditional plate processing equipment, and can provide nearly unlimited dot profiles (shoulder angles and tip shapes). While these machines can provide some unique capabilities, they can be quite expensive. Here are some key factors to take into consideration:

Direct Engraving Pros:

  • Two step platemaking process (engraving, cleaning).
  • Nearly unlimited control of dot shape and shoulder profiles.
  • Seamless imaging capability.

Direct Engraving Cons:

  • A limited number of materials can be engraved using this process.
  • The engraving laser can only produce one sheet/sleeve at a time, so throughput is considerably less than other platemaking processes.
  • These machines are typically large and can require filter and suction equipment to be installed in a separate, specially-designed room.

Direct engraving devices are available from SPGprints, Hell Gravure, Luscher, and Kodak.

Negatives Without the Negativity

If the analog platemaking process better suits your company’s needs, or if you are using liquid photopolymer, continuing with film may be the best option for you. Thermal film imagesetters provide durable, high quality film negatives (or positives) with the convenience of a thermal desktop printer. These devices utilize a precise thermal imaging head paired with a special thermally-sensitive film to create finished film in one step. No chemical processing, no additional equipment, no hassle. All Printing Resources carries the EXILE line of thermal imagesetters, which offers a variety of sizes for nearly any application.

Thermal Imagesetter Pros:

  • Excellent density, crisp edges – suitable for many applications.
  • Durable film can be stored for 20+ years without degrading.
  • Fast, chemical free film output. No processing or darkroom required.
  • 1200 x 1200 dpi resolution is suitable for fine line work and screen rulings up to 120 LPI.
  • Small device footprint, no extra equipment.

Thermal Imagesetter Cons:

  • Not suitable for screen rulings over 120 LPI.
  • Thermal print head is a consumable, but replacement can be covered with film purchase agreement.

Inkjet film printers are also available, but image quality is compromised as compared to thermal film or traditional imagesetter film The images in Figure B show the difference in edge definition and image formation between these two technologies.

Figure B – Comparing Thermal and Inkjet Film Imaging Quality


EXILE Technologies (formerly OYO Instruments) is a leading manufacturer of professional-quality thermal imaging equipment, film products, and direct-to-screen devices. EXILE Technologies is proud to manufacture all equipment in the United States.

If you are new to digital platemaking, or simply looking to upgrade your current equipment, All Printing Resources can help. We offer the equipment options, on-site training, and flexographic printing know-how to ensure your plate making process is completely optimized and performing to it’s full potential.

Quick Reference Chart – Plate Imaging Options

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Filed under Prepress, Printing

Plugged Cells?


Cell plugging is a common issue associated with anilox rolls. It is a costly problem that can be controlled or eliminated from your process through the use of recent technological advancements and a preventative maintenance program. Instead of listing the many problems that cell plugging creates, I’ll get right to the real focus of this article: how to maintain consistent anilox volume control. We all know that there are an enormous amount of variables in the Flexo process. In order to stabilize those variables and maximize your investments, it is up to you to control the issues that are within your power. This article is intended to give you the tools to do just that.


The Anilox Roll

The anilox roll is the mechanical heartbeat of every Flexo process. With each beat of that anilox heart, there is either a sellable or a non-sellable product being created. Managing the variables of the anilox process is where the preventative maintenance program really comes into play. Controlling, tracking and performing scheduled preventative maintenance are the keys to ensuring the making of a consistently sellable product.

Press operators and their support team are the human heartbeat of preventative maintenance. Their cooperation and proper training will maximize your anilox investments and facilitate the production of consistently sellable product off the press. The process is as follows: the volume of each anilox correlates directly to the ink film thickness consistently being transferred to the plate; the ink that is being metered by the anilox must be maintained at optimum and recommended pH/viscosity levels to ensure precise and uniform ink release, as well as a decrease in plugging issues. Common practice by press operators is to add base to ink on press to compensate for inadequate printed ink density and this is costly. A individual anilox rolls unanticipated volume loss, creates the need to make ink adjustments or change anilox rolls. Due to the intricacy and importance of the anilox roll, operators need to; care for them, get to know them, and subsequently trust each roll in their mix to maintain the highest levels of productivity.

Technologically speaking, recent advancements have given rise to improved cell geometry and greater consistency of engravings. Pamarco’s EFlo engraving is a prime example of an advancement in anilox cell geometry. This new technology  provides the ability to improve both productivity and metering consistency.

EFlo engraving

The EFlo engraving is an extended cell that allows for 15% more ink release, while having the shallowest, flattest-bottomed cells. The shallow shape of the cells means longer running press times without the need for stopping to clean up. Longer press times means increased productivity. Cell-plugging issues are also reduced through the use of the shallow cell geometry, making it easier to thoroughly clean and maintain consistent ink films. These translate to an increased line screen of your anilox roll when converting from conventional → EFlo, due to the improved control of ink release.

Cell Plugging & Effective Anilox Care

Information compiled by Pamarco through anilox evaluations points to many converters struggling with both cell plugging and effective anilox care. Cell volume is one of the keys to understanding these problems. The cell volume is measured in Billion Cubic Microns or “BCM.” This is the volumetric capacity of ink or coating that an individual engraved anilox cell can carry. Maintaining uniform volumetric capacity throughout all of the engraved cells on an anilox roll is critical in effectively producing consistent, quality products. It only takes a 10 to 15% reduction in cell volume because of plugging to create consistency issues on press. Pamarco’s Cell Restore has been proven to be a solution to this difficulty throughout the industry, and was formulated specifically for breaking down cross-linked, water-based resins.

Cell plugging is caused by a build-up of dry ink or coating in the cell bottoms. Cell Restore was engineered with a focus on breaking down and swelling the dry ink, and that’s exactly what it does. It is a neutral pH, spray-on solution that fractures cross-linked resins on a micro emulsion layer, without jeopardizing the life span of the ceramic coating. It is also very user friendly. After applying the Cell Restore and letting it work for 5 minutes, a micro-fiber pad is used to remove the swelled and suspended resins from the cells. It is recommended to incorporate this cleaning solution into your regular Preventive Maintenance schedule to prolong the time period between major cleanings (I.E. Soda Blasting Units from Eaglewood Technologies Sanilox System).

In conclusion, incorporating a comprehensive program focused on maintaining the integrity of your anilox roll inventory will add value to your investment.  Your process will see a reduction in hidden costs, improved quality and greater consistency. The print nip for each unit of a Flexographic press should be looked at as a body, surrounding its mechanical heart (the anilox roll). It works to the favor of both the printers and the converters to collaborate with and draw upon the expertise of their vendors. When properly utilized, the relationship that you have with your anilox roll vendor can greatly benefit your business.

About Pamarco:

Committed to the market since 1946. From offering the most extensive portfolio of products on the market, to offering the best consultative advice, to delivering an overall superior customer service; all underpinned by their passionate corporate culture, Pamarco has been able to build enduring and meaningful relationships with converters and OEM suppliers all around the world. To find out what Pamarco can do for you, visit www.pamarco.com.

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3 Tips to Prevent UV Ink Spitting


by Doug Jones, Apex International

UV inks are considered by many to be the most popular in the narrow-web space.  And for good reason.  Print results with UV inks are consistently better than those using water or solvent-based inks.  But the use of UV inks is not without its challenges.  Chief among those challenges is the issue of spitting.

There are several theories as to why spitting occurs with UV inks and not with water or solvent inks.  Generally, these revolve around the higher viscosity of UV inks comparied to water or solvent and the impact it has on the doctor blade.  Specifically, the higher viscosity can move the blade just enough to allow more ink than is intended to slip through.  Other theories suggest that anilox cell type, viscosity, press speed and doctor blade specifications all play a role.  Regardless, the results can be a disaster, particularly at high speeds.


While exactly why spitting occurs is a subject for debate, what is not in dispute is that the relationship between doctor blade and anilox is at the core.  If spitting is creating a challenge in your shop, try these tips for better print results:

1. A stiffer doctor blade may prevent excess ink from getting under and transfering to the plate and substrate.

Testing shows a thicker blade will minimize UV spitting because they resists hydroplaning and do not allow texcess ink to transfer to the anilox.

2. Try a 30° anilox cell with openings

The ink can move through the openings in the anilox cell walls preventing ink from being built up onto the back of the doctor blade.  (Situation 1a).


A word of caution: This solution is only temporary. Because the roll will wear over time, the openings will become smaller and eventually disappear. So over time you will get the same situation as with the regular anilox roll. Ink will built up at the back of the doctor blade (situation 1b).

3. Try GTT Channel engravings.  

There is no pressure built up at the doctor blade because the ink can move through the GTT channels. Therefore no ink builds up onto the back of the doctor blade and no ink drops from the doctor blade onto the flexographic plate or substrate.


Get the flexo solutions guide now!


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Filed under Anilox Rolls, Print Defects, Printing

Cut Print Production Cost & Improve Quality and Consistency


From the time Printing has been accepted as a means of communication, the effort has been to transfer ink from the tray to the substrate. There have been consistent developments and the target has been to improve the quality of fixed palette or expanded gamut print, for short or long run.


Different printing processes also developed to suit the printing of various substrates. All the printing processes have some common factors. These are:

  1. Transfer ink from a tray(container) to the substrate.
  2. Use the correct shade of ink to get the correct shade in print.
  3. Use the correct volume to get the correct depth.
  4. Distribute the ink uniformly to get even colour across the substrate and to get the correct tonal gradation.
  5. To use the best resolution possible on the press. This is not always true. As there are presses that can print higher resolution, but even than lower resolution is used:
    1. To suit the substrate being used
    2. To be safe with a lower resolution
  6. For multicolour printing to use CMYK + pantone inks of the correct hue and density for correct colour reproduction.

To achieve the above objective every effort has been directed towards improving the depth of the colour and range in print. In the process a higher volume of ink is being used that produces a thicker layer on the substrate and requires more energy to dry.

One look at the recent development that have taken place in the Flexo industry will show that all the photo polymer plate manufactures have tried to:

  • Target improved ink transfer in the solid areas to improve the ink transfer(increase the ink volume) to get a higher solid colour depth.
  • Trying hard to hold a finer dot(of 1% and below) of a finer screen ruling on plate, at a higher plate and equipment cost that add to the cost of processing the plates
  • This capability is limited to the use of special plates and software meant for use with these equipment.

All these require higher investments and add to the cost of production.

Almost all anilox roll manufacturers have tried to create a higher cell volume with finer screen rulings so as to provide the required depth of colour in the solids when using the finer screen on plate.

The time has come to look at the possibility of changing this by:

  1. Using standard lower density inks for most jobs, improving the printing of the highlights.
  2. Using a more uniform and thinner layer of ink, without losing the required print densities
  3. Improve press speed and production capacity
  4. Improve the colour gamut in print while eliminating the need to use pantone shade inks
  5. Black ink uses carbon as the main ingredient. The reduction or elimination of black ink in print makes printing more environment friendly and provides you with carbon credits. It makes packaging of food more healthy and less toxic.

That helps reduce the cost of printing, while producing a greater depth in colour, improving the print range and reducing the energy to dry the thinner layer of ink. When you do this change you:

  1. You eliminate the inventory of Pantone inks
  2. The make ready time required to match the colour in print, on the press. It also reduces the cost of wasted /unused Pantone shade inks in stock at the end of the year, every year.
  3. Reduce the anilox inventory and use the same anilox rolls for almost all jobs.
  4. Reduce the overhead costs, with reduced press down time, as you use the same anilox rolls for the same colour on the same station.

One notices that Gravure printing is able to achieve the highest print densities even though they use liquid inks, while in Offset printing the ink densities are the lowest. This is because the ink layer laid on the substrate, in offset, is the thinnest.

If we are to reduce the density of the inks we use in printing than the cost of the inks would come down. By reducing the ink density we are reducing the density of the highlight areas. This will reduce the effect of dot gain in the highlights, which is a major problem in flexo printing. This small change will enable us to print the fine highlight details easily and cleanly. It will also allow us to print the vignettes smoothly even when we use coarse screen with coarser screen anilox rolls. Even though the coarser screen anilox rolls use a higher cell volume and will provide a thicker layer of ink, the lower density in the highlights will reduce the effect of the dot gain to the eye and provide the required softness to the image.

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Enhancing the Colour Gamut in Fixed-Palette Printing


by Doug Jones & R S Bakshi

Multicolour or fixed palette printing is generally associated with printing with 4 process colour inks namely CMYK. Sometimes it also uses additional Pantone shades, to produce a colour shade that is not reproducible using the CMYK process colours. This system has been in use for many years and is still in vogue. In many cases, higher density inks have been used to improve the printing of process colours by using higher density inks to produce the richer/darker colours. Though this helps to improve the richness of the colours, it makes the highlights darker in print which can at sometimes be drawback.


There have been attempts to improve the printing of process colours by printing 6 colours namely CMYKOG which came in very powerfully, but somehow never gathered momentum.

Thereafter another system came in with improved capabilities. Over the years that team has worked very hard to improve its performance, in more ways than one. The present system if fully equipped to help the printer get full benefits, by using this system.

Of late, there has been a lot of interest in creating awareness in following the 7 colour system of printing, with a consortium of companies coming together to focus on this system, now known as the REVO project. I think this is a good move as it will benefit the printers, substantially, to follow this system of 7 colour printing, as a standard practice. This principle of 7 colour printing, can be practiced independently of the companies of the consortium and a printer is free to choose the partners it he wants.

The best part of the system is that it gives the pre-press department, the ability to convert the RBG/CMYK image into separations for CMYRGBK, within no time, that enhances the Colour Gamut reproduction which is very easily seen on the monitor itself. This is the only software, I have seen, that can do this without batting an eyelid. Earlier we used to spend hours in trying to prepare a separation for printing a Pantone* shade to combine with the CMYK image, by manipulating the CMYK image separations. The system also allows you to edit the separations, to an extreme, that I have not seen before. Also the editing functions are simple and easy to manage.

The improved Colour Gamut that one sees on the monitor can be easily reproduced using the defined set of inks. It also improves the appearance of the metallic colours like gold and silver which is really amazing. The use of the ink suggested can also be used as standard for printing of all jobs, irrespective of the printing process or substrate used. The essence is to use a good white substrate with the standard set of inks.

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The names used in this article with an * are the registered Trade Marks of the individual companies.

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Flexo’s Future – Expanded Color Gamut


by Richard Black, All Printing Resources, Inc.

The Flexographic print process has long been thought of as a simple print process, not capable of the same quality as the lithographic print process. In the last five years there have been many advances in plate technology, digital platemaking process, and screening that have dramatically improved the quality of Flexo. It is very common today for converters to run 150 lpi, and many have made the jump to 175 or 200 lpi along with the ability to fade screen vignettes to zero. These specifications would have been virtually impossible a few short years ago.

Is ECG Just the Latest Trend?

The ability to print fine screen rulings and fade screen vignettes to zero have made a resurrected technology possible, printing with an Expanded Color Gamut (ECG). ECG printing has been around for quite some time. The Lithographic industry has been using it, in limited areas, since the early 1990’s. Matter of fact, in an article written by Don Hutcheson for the 1999 GATF Technology Forecast (www.hutchcolor.com/PDF/HiFiupdate98_2000_04.pdf) the following Extended Gamut systems (then called HiFi Color) were commercially available in 1998:

  • Hexachrome (CMYK+OG) – Pantone
  • MaxCYM (CMYK+CMYK) – Royal Zenith and then the basis for DuPont’s HyperColor
  • Opaltone (CMYK+RGB)

Why Are We Talking About it Now?

FLEXO Magazine Cover - Oct 2014 Expanded Color Gamut - CMYK+OGV

FLEXO Magazine Cover – Oct 2014 Expanded Color Gamut – CMYK+OGV

So, if the technology has been around for so long, why is everyone in Flexo just now talking about it?  The main reason is the ability to reproduce a majority of spot or Pantone colors using only 7 inks, CMYK+OGV. This has recently been demonstrated with the 2014 & 2105 fall covers of FLEXO Magazine.

Last October the front cover was printed Flexo using 7/color ECG and the back cover was also printed Flexo using standard 4/color process. The color difference and Pantone color match was amazing using the 7/color ECG process.

The 2015 November cover of FLEXO Magazine was again printed using the 7/color ECG process but this time it was compared to a 4/color cover printed using litho.

Award-winning connections

Gidue Wins 2015 FTA Innovation Award

Gidue Wins 2015 FTA Innovation Award

We (APR) were lucky enough to be involved in both projects. Earlier this year Gidue (now Bobst) was notified that they had won the 2015 FTA Technical Innovation Award. The award was presented to Gidue at the FTA Forum/InfoFlex in May.

The FTA asked Gidue if they would like to participate in printing the November cover of FLEXO Magazine using theGidue M5 Digital Flexo Excellence Press located at the APR Technology Center (located in Glendale Heights, IL), along with the 2014 FTA Technical Innovation Award Winners,Esko Equinox and SpotOn! Flexo. Gidue agreed and project planning began. The goal of this project was to demonstrate the quality of 7/color ECG printing versus normal 4/color process printed litho.

Putting it all together

In August, APR hosted 12 industry-invited personnel, plus a few of us at APR, to print from scratch, the November cover of theFLEXO Magazine. This meant we needed to Optimize, Fingerprint and Characterize the Gidue press prior to actually printing the cover. This process required 4 press runs and 16 plates before we had the proper information to create the profile and the final 7 plates required for the cover. The process is intense but the results are amazing.

Below is an example of the 4/color Litho cover versus the 7/color ECG Flexo cover printed at APR.

FLEXO Magazine Cover - Nov 2015 Standard Process Color - CMYK

FLEXO Magazine Cover – Nov 2015
Standard Process Color – CMYK

FLEXO Magazine Cover Nov 2015 Expanded Color Gamut - CMYK+OGV

FLEXO Magazine Cover Nov 2015
Expanded Color Gamut – CMYK+OGV











You can see how vibrant and colorful the 7/color ECG cover is compared to the normal 4/color cover. Also note the Purple in theFLEXO masthead, as well as, the green and yellow side bars. These areas are spot colors that would normally have to be run in their own print station but with 7/color ECG process you can reproduce these and virtually any other color.

The November FLEXO Magazine debuted November 3, 2015 at the FTA Fall Conference in Columbus, OH. The following link will direct you to the electronic version of the 12-page article that appears in the magazine.


These two magazine covers demonstrate that the 7/color ECG process is viable and the products/technologies required for this process are commercially available.

Industry-wide acceptance of Expanded Color Gamut

Pantone Extended Gamut Guide

Pantone Extended Gamut Guide

Another major step forward in the acceptance of the 7/color ECG process happened in September when Pantone announced a newPantone® Plus Series Extended Gamut Coated Guide printed using the 7/color ECG process. www.pantone.com/what-is-extended-gamut

For years we (the printing industry) have shown content creators and designers the Pantone Plus Series Formula Guide®, and said you can pick any 2 or 3 of these colors, that we would run as a special or spot color. With the new Extended Gamut Color guide, content creators and designers can pick as many of these color as they want!


Hands-on experience with Expanded Color Gamut Printing

APR & Esko ECG Seminar Sample Job

APR & Esko ECG Seminar Sample Job

Earlier this year, Esko and APR held an Expanded Gamut class where we produced a series of labels printed on the Gidue M5 press using 200 lpi and Esko’s Full HD Flexo & Equinox technologies both in 4/color process and 7/color ECG.

The results were amazing. The 7/color ECG labels faithfully reproduced all 15,  yes 15 Pantone colors. So imagine if this was a commercial job and the customer asked you for a label with 15 Pantone colors, what would you do?  It’s not IF ECG will become the standard for Flexo printing it’s WHEN, and the when is quickly becoming now!

Kind of makes you scratch you head doesn’t it

To read the original article, visit https://www.teamflexo.com/flexos-future-expanded-color-gamut/?

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Corrugated for Retail-Ready Packaging & the Technical Problems that may Arise when Flexo Printing



By Tom Kerchiss, RK Print Coat Instruments Ltd


The Retail-Ready packaging (RRP) concept has boosted the demand for corrugated/micro flute systems; a situation that is set to continue as major retail chains and superstores not only in North America, Europe and Australasia but also in the Far East adopt RRP with enthusiasm.

Retail Ready Packaging makes economic sense for high volume retailers, especially at a time when many of the major superstore groups have seen forecasted profits fail to materialise and shareholders and city investors become more insistent that economies are put in place and operational efficiencies are made. RRP aims to reduce product handling, increase speed of replenishment, reduce packaging material and costs and improve shelf display. RRP and high quality printing should go hand in hand as the concept is designed to reinforce product branding throughout the supply chain. Over 80 per cent of the product should be visible on the shelf and primary consumer information, which normally goes un-noticed unless the product is picked up and handled, is made highly visible on the retail ready tray.

Corrugated material and folding carton are in many respects ideal display and packaging mediums for RRP. If we just consider corrugated for the moment it combines both strength and rigidity with the flexibility to absorb shocks, corrugated board also makes good use of minimal material. There is hardly any other material that this author is aware of that gives such rigidity using so little material. These interesting properties are obtained by gluing various layers (at its basic), an undulating middle layer (flute) with plain layers on either side: the result of which is a light and rigid framework, the principle of which has been adopted by the aero industry in wing construction and in civil engineering in bridge construction.

In many instances today – Retail Ready Packaging arguably being one of them, the consumer will not always even be aware they are encountering a corrugated medium. The reason being that the characteristics of the material and its presentation have changed so much in order to meet not only the self- service requirements of the modern retail environment, but also the requirements of brand owners. In this case the brand owner and marketing organisation may be seeking to either promote established premium products that need a high volume of packaging featuring ultra high quality printing to support the brand and attract attention, or perhaps newer or promotional products that will be shipped in low volumes, packed in high quality printed boxes with the shelf appeal to generate demand. Even low cost commodity style products that need high volume cost effective boxes with fewer colours and less elaborate branding benefit from the RRP approach, bottled sparkling/natural and flavored waters serve as an example.

In corrugated applications the substrate plays a major role in dictating how the ink is going to appear on the finished job. Much of corrugated board is printed flexo, either directly onto finished board or as is most often the case when presentation is important via pre-printing on the outer layer or liner or by laminating. Defects that can occur during the corrugating process may impact on print quality and on production rates. These defects are associated with flute integrity, caliper, wash-boarding and warped board. Ink formulation, photopolymer plate selection, anilox and inking systems must be chosen or formulated with care if print quality and workflow consistency is to be maintained.

The technique of pre-printed liner has revolutionized decorative possibilities. It is however expensive, to make it economical pre-print tends to be considered for longer runs and where a prestigious impact needs to be considered. Another option is to laminate a pre-printed liner, giving the best results since printing can be undertaken on the highest-grade paper. Again an expensive option but recommended where high value consumer goods are being sold. In a RRP situation pre-printed liner and laminated would tend to be confined perhaps to big-ticket gift items, electrical and home/garden furniture goods.

Although the introduction of pre-printed liner and laminated materials as well as an increasing number of engineered flutes have undoubtedly changed printing board, a degree of watchfulness and care may be necessary when for instance flexo printing some jobs as the medium can be challenging.

The substrate can play a major role in dictating how the ink is going to appear on the finished job. Absorption and surface tension are the main factors that influence print density as well as drying, trapping and dot gain. It is also important when providing a customer with s colour match that the exact same substrate is the one that is finally to be used.

Printing one colour on Kraft, mottled or even clay-coated sheets that seem to have the same surface appearance will yield a wide range of shades even from the same colour. The reason for this is that the sheets with a high level of absorption produce a weaker colour due to the ink being absorbed into the substrate. Conversely those sheets with lower absorption properties will display stronger colours; if clay coated sheets are used the ink may not even penetrate the substrate surface. Surface tension plays a role in determining colour strength.

If the situation arises whereby it is necessary to print on clay-coated board, insufficient coverage or poor trapping may well occur together with poor adhesion due to the components of the ink having a combined surface tension that is higher than that of the substrate. This produces a cohesive effect, causing inks to shy away from some areas of the substrate surface and produce an uneven appearance to the final print. Inks with a higher level of polymeric additives and incorporating a measured amount of water can be used to good effect. In this instance the water is added at the press side to reduce viscosity so that faster drying and faster press speeds can be obtained. Care must be taken as too much water causes an imbalance in the ink, reducing rub resistance and gloss. A diluting vehicle will maintain ink balance.

The rub resistance that printed ink exhibits in some instances may well have to be modified. For example: Kraft, mottled and bleach board tends to show more rub resistance than a clay -coated board. Rub resistance is adjusted with waxes and specific polymers and a sample preparation or colour communication device such as the FlexiProof is ideal for monitoring results as well as for product development including inks and substrate. The FkexiProof 100 or variants FlexiProof UV and FlexiProof UV LED are also suitable for conducting tests associated with rub, wear resistance, scratch resistance, gloss and other desired properties.

On a clay coated board the ink supplier needs to be aware if the board is going to be overprinted with a varnish. Normally if complex graphic printing is undertaken on a clay-coated medium the varnish is added for protective barrier purposes and for gloss. It would be counter-productive to add a wax additive as this would not only reduce the gloss but cause problems with a solid over solid trapping.

The pH of inks used for graphic printing on clay-coated board is generally higher than for Kraft board. The reason for this is that the inks tend to incorporate more in the way of polymer and the inks contain a balanced level of water. The higher pH helps stabilise the ink and helps make it stay open longer, slowing the drying of the ink on the printing die. A lower pH range is advisable for Kraft type boards because these are generally printed at faster speeds and quick drying is necessary.

Adjustment of pH is usually done with amines or ammonia with the former being the most stable and the latter not being recommended because of potential health risks. The one constant is that the ink pH must be checked from time to time to prevent changes that may arise due to evaporation. A pH stable ink is the best option requiring much less in the way of attention.

For more information, visit  RK Print at www.rkprint.com

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