Tag Archives: flexography

3 Ways Flexographers can Win Over Brand Owners

Apex International Blog

by Doug Jones, Apex International

The only thing more difficult than earning the business of a new customer is keeping it.  Printers working with brand owners sometimes have a hard time differentiating themselves in the marketplace and demonstrating consistent value.  There are three areas in maintaining a brand owner relationships where your efforts will most certainly be rewarded!

1. Help brand owners reduce cost

Every brand owner is looking to spend less on materials and the “buy more, save more” approach that has resulted in longer and longer runs is not a viable solution.  Instead, brand owners want the flexibility of just in time without having to absorb a price increase.

The key to saving brand owners money while running a profitable business is volume and efficiency.  Your goal is to become their preferred printer because a) you have demonstrated your commitment to the partnership and b) you have a real, tangible success strategy that details exactly how your process is more efficient and more consistent than the competition.  Managing shorter runs profitably is only possible if you are still able to minimize machine down time in the process.  One tried and true way to accomplish this is by eliminating variables and increasing overall operational efficiency.  Reducing the color palette, for example, is one way to drive efficiency and reduce costs.  Taken a step further, an optimized fixed palette solution will certainly provide any printer with a competitive advantage.

Tip: Provide brand owners and retailers with the ability to have high print quality on a wide range of substrates. 

2. Help brand owners manage inventory

If you have the space, a vendor managed inventory (VMI) solution can help you demonstrate value by creating an efficient print management system in partnership with your customer.  With VMI, you’ll work with your customer to establish stock level minimums and maximums based on forecasting models.

The upside for the printer in this scenario can be enormous.  First, you will become very “sticky” with your customer in terms of the relationship.  Established VMI partnerships are difficult to break.  Second, you will be able to complete longer runs while still delivering just in time value.  You’ll have greater control over the planning process and more flexibility.  Third, printing in volume allows for greater overall print consistency.

3. Help brand owners manage their brand standards

Printers running the same job at multiple sites or even with multiple machines in the same site understand the common standard expectation brand owners have.  Generally, brand owners have little concern over where a job is printed or by whom so long as the common standard is met.

The key to successful brand standards management across multiple sites is consistent, predictable printing.  Optimized fixed palette is one means by which to ensure consistency across all stations.  In fact, many of the same cost reduction strategies you can use to win over brand owners will ultimately help you deliver more consistency.

Get the Flexo solutions guide now!

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Filed under Branding, Printing

Big Value, Small Environmental Footprint

Asahi Photoproducts - Asahi Kasei

 

 

By Dr. Dieter Niederstadt – Technical Marketing Manager Asahi Photoproducts

 

 

 

 

This is what drove Nu-Maber, a leading Italian repro house, to choose Asahi AWP-DEF water-washable plates with Pinning Technology for Clean Transfer. The company is known for being innovative and forward-thinking, and has many firsts to its name. Being the first in Italy to adopt Asahi AWP-DEF plates adds another diamond to its crown.

Nu-Maber Blog Post with Livio Simionato“We wanted to stay current with the latest trends in flexography in order to deliver plates of the utmost quality to our customers, while also taking into consideration the environmental footprint of the platemaking operation,” said Livio Simionato, Nu-Maber’s CEO. “After reviewing the options available in the market, we chose to partner with Asahi, and we have been able to grow our business in both narrow web and wide web markets using Asahi AWP water-washable plates, for printing on paper and plastic substrates .

Simionato was also concerned about the environmental impact of platemaking, both in his operation and that of his customers. “One of the attractions of these water-washable plates,” he explains, “is the elimination of the solvents required for the production traditional flexo plates. But perhaps even more importantly, the Pinning Technology for Clean Transfer that is a hallmark of these plates results in a cleaner overall printing process with fewer press stops for plate cleaning, improving pressroom productivity for our customers and reducing waste.”

Simionato and his team are working hard to educate the Italian flexographic market about these benefits. “Asahi studies show significant improvements in overall equipment effectiveness,” he says, “which means much less waste and significant time savings. We’re seeing this in action with the customers who have adopted these plates, and we want to make sure that everyone in the Italian flexo community has access to these outstanding plate solutions that will drive their productivity and their profits while also improving quality.”

Pinning Technology for Clean Transfer is also ideally suited for Fixed Color Palette printing using a fixed set of 4 to 7 inks and requiring precise plate-to-plate registration, a printing process that is growing in popularity among packaging converters and brand owners alike. Some experts estimate that fixed color palette printing using seven colors can match as many as 90% or more of the 1,838 named Pantone spot colors, reducing ink inventories and improving efficiencies.

View Video – Asahi Photoproducts – NuMaber AWP Interview

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Filed under Plate Technology, Printing

The Rise of Pantone Simulation in Flexography

The Rise of Pantone Simulation in FlexographyRecent studies and trials aimed at optimizing Pantone simulation suggest that the fixed palette approach is ready to revolutionize the flexography and label industries. The change is due specifically to advancements allowing for unprecedented process control and consistency as well as the development of new tools designed to pinpoint which process parameters are failing so they may be addressed before problems arise.

4C  No limits – No compromise!

According to Nick Harvey – Print Application Director of Apex International – 4 color fixed palette has many advantages over 7 color simulations in for particular for wide web Flexo. First you must understand and consider that existing wide web printers have:

  • Many existing designs that they hold plates in stock for (100,000’s Euro’s)
  • Many ink press returns in stores that require re-formulating for spot color printing (1000‘s Euro’s)
  • A number of customers that will not move old designs to Fixed Palette

When you understand and consider the above, printers require a transition solution to move over to Fixed Palette. Apex 4C using the GTT technology offers this smooth transition. Harvey states that an estimated 90% of printers only have 8 color presses and therefore 4 color Fixed palette plus White allows for printers to use the spare 3 units for:

  1. Spot colors that are not possible with 4C simulation and this gives the possibility to print 100% of the pantone book.
  2. Printing designs side by side saving set up costs, increasing run lengths, increasing profits
  3. Printing up to 800 colors at the same time (a designer’s dream)
  4. Printing added value combination lacquers, Gloss, Matt, Tactile
  5. Printing up to 800 Metallic colors at the same time just by backing simulations with silver
  6. You still have the possibility to increase to 5, 6 or 7 C as and when it suits your business needs and your production is comfortable and consistent with 4C.
  7. Finally the ability to print all existing designs in the current format without disturbing the 4C fixed process set.

Added to the above moving to Fixed Palette printing in the first instance is a matter of variable elimination in order for printers to make the transition into Fixed Palette Color simulation they need to optimize their internal process control which requires a mind set to remove / eliminate as many process variables as possible.

Therefore starting this journey into Fixed Palette is much smoother when you begin with the already familiar Y M C K process set. When it is understood that 4C brings a possibility of more than 800 colors within a delta e of 2 this is already a huge step forward, whilst at the same time allowing all existing designs to be printed and press return inks to be used away during the transition as stated above.

The demand for optimized fixed palette is only expected to grow as brand owners demand better color consistency with shorter run lengths and just-in-time production. Chief among these concerns is the ability to create color consistency across multiple markets ensuring that the same values and same Pantones can be printed on labels just as they can on films.

For more than a year, Apex International has been involved in a project to proof that Fixed palette printing with only 4 colors is the future of the Flexographic printing industry. At Drupa the results of the trials will be presented to the international Flexographic printing industry.

What is so special about this project?

Fixed palette optimization through advances in color management and process consistency has fundamentally changed flexographic printing in the 21st century. Brand owners around the world have taken notice. In fact, more and more brand owners are choosing printers with a proficiency in fixed palette. Two leading brand owners – Asda/Walmart and Morrisons – have contributed their participation to the project from the start. They have offered designs of some of their packages to be used and printed in the trials.

Secondly, the designs contain packages that were previously printed in various different types of printing techniques, going from Litho to Aluminium foil lidding, from Gravure to Surface Prints in Flexo and from UV Label to UV Shrink sleeves. All these designs are now printed in Reverse on OPP in Flexo!

Third, the number of different designs per printing plate are incredible, all printed with CMYK. For the Morrisons design more than 100 Pantone colors were matched and 28 (!) designs were printed. The Asda printing plate covered 17 designs and also here more than 100 Pantone colors were matched!

“Nothing is Impossible”

Apex International has proven that the impossible ís possible by presenting print results in UV label, OPP Polythene and Offset/Litho. Visitors to Drupa can come to the Apex booth and check the color results with their own eyes, as well as with the X-Rite Color management equipment Exact Scan & ColorCert Master. Since it is about matching the original proof that is signed off by the brand owner, the Apex stand will also provide this original proof.  And as if that weren’t enough proof, Apex also displays some of the original packaging the way they can be purchased in the supermarket nowadays.

The Morrisons Print Proof

The Morrisons Print Proof with 28 designs previously printed in different printing technologies, now all on OPP Reverse Print in Flexo.

The ‘role’ the Anilox played

“Achieving color consistency is probably the most difficult component of transitioning to a fixed palette process.” says Bas van der Poel, Technical Sales Director EMEA at Apex International. “Fixed palette is about control: control over variables, control over ink flow and so on. It is this control that has allowed us to hit the number of Pantones we have with these trials and do so while not having to make any changes to plate inventory. It requires a level of control that simply is not possible with conventional anilox rolls.

Apex holds globally recognized patents on the award-winning GTT technology that uses continuous lasers to engrave a slalom pattern onto the anilox. The continuous laser is responsible for creating an anilox product capable of the smooth, consistent and controlled laydown necessary to optimize fixed palette. The Fixed Palette 4C consists of 4 GTT rolls/sleeves and one calibration roll/sleeve for closed-loop control and a guaranteed process stability”.

Get Your Fixed Palette Sample Kit Now

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Filed under Color Management, Printing

Lower Your Anilox Line Screen and Cell Volume for Better Performance!

pamarco-logo-400

by John Rastetter and John Bingham, Pamarco

It sounds counter-intuitive to lower your anilox line screen to improve performance but that’s exactly what we are proposing. Read on for a detailed review of the logic and the results.

For years anilox producers have been recommending that printers increase the anilox line screen to improve print reproduction. The thought is that by increasing the anilox line screen more support is given to the printing plate, producing cleaner print. Increasing line screen does insure that more cell walls contact the plate, but what it primarily does is reduce the percentage of cell volume that is transferred to the printing plate. The lower transfer efficiency creates a thinner ink film. A thinner ink film in turn produces cleaner print. However, there are negative side-effects of increased anilox line screen ; plugged cells, scoring, and pre-mature wear.

Lower Your Anilox Line Screen and Cell Volume for Better Performance
On the left is the EFlo cell technology and the right the HourGlass cell, note the clean sharp cell formation created by fiber-optic laser technology
 

Pamarco feels there is a better way to produce the same, or improved print result and at the same time increase ink transfer consistency and anilox durability. This is accomplished by decreasing the anilox cell count and reducing cell volume to produce anilox engraving that provide the correct ink film thickness, more consistent ink transfer and an engraving that is more durable.

Today’s anilox technology utilizes fiber-optic, multi-beam, Thermal engraving technology. To be more specific, Instead of using a blend of gases, mirrors, and tubes to produce a single laser beam, a crystal creates a short pulse-length beam that is so powerful a single beam is split into as many as four smaller ones. The splitting of the beam is what currently enables anilox cells to be “multi-pulsed” or “multi-cycled” creating cells that are “carved” with precision. The end result is a great deal of heat and energy directed into the cell of an anilox within a very short time-frame.

The benefit of fiber-optic technology is the ability to produce a wider range of line screens (35 lpi to over2000 lpi), increased cell depth and increased volume per line screen. This fiber-optic technology also allows us to create cell bottom that are flatter, shallower and smoother than a comparable CO2 laser engraving. Software advances in conjunction with this laser technology allow us to produce new cell shapes like EFlo and HourGlass, these new cell designs add additional performance benefits as well. However, If not implemented correctly the down-side of this technology can be a reduction in cell durability (resistance to scratching, scoring, and premature wear).

Older CO2 technology typically burned / engraved cells with a single pulse and at a pulse-length much longer than fiber-optic technology. CO2 technology does not vaporize as much of the ceramic that is burned away to form the cell, leaving a rim of melted ceramic on the cell walls referred to as re-cast. Melted and re-hardened ceramic is believed to be harder than the “as sprayed” ceramic on the surface of the anilox. This recast assists with durability of the engraving. Fiber-optic technology, because it burns at a shorter pulse length creates recast in a different way, it tends to accumulate in nodules or posts at the corners of the cell. If cell geometry is not correctly established by utilizing an acceptable depth to opening ratio, the multiple pulses inside each cell can over harden the nodules, causing them to become brittle. The end result can be chipping or breaking of these particles, creating pre-mature wear and/or tiny scratch or wide score lines on the anilox.

Since the anilox industries implementation of Thermal lasers, the focus has been to increase anilox line screen and cell volumes. Where a 4.0 bcm may have been utilized at a 400 line screen, today it is common to produce the same volume at a line screen of 600 and higher. The 600 line screen at a 4.0 bcm produces cleaner print than a 400 line screen at a 4.0 bcm because less of the 4.0 bcm volume transfers to the printing plate. This is caused by the fact that deeper cells have a lower transfer coefficient. The resulting transfer produces Print that is cleaner, but density is reduced and engraving life is compromised. Pamarco thinks a better approach, in most cases, is to decrease the anilox line screen and cell volume to reduce the ink film thickness transferred to the printing plate. This will produce cleaner print, targeted ink densities and anilox cells that are more resistant to wear and plugging.

Lower Your Anilox Line Screen and Cell Volume for Better Performance - engraving-testing
“Above are photographs of the 450 lpi – 3.4 bcm and 600 lpi – 4.0 bcm engravings tested on the banded roll. Cell depth on the 450 was 15.5 microns with a 53.4 micron opening (29% depth-to-opening ratio) versus a cell depth of 20.3 microns with a 40.3 micron depth (50% depth-to-opening ratio). Note the improved smoothness of the cell walls on the 450 lpi”.
 

An example of this can be illustrated by a recent banded roll test. A test was done to determine if a better alternative is available to a 600 lpi, 4.0 bcm, 60° cell used by a customer for combination process/line work/solids printing and a 900 lpi, 2.6 bcm, 60° cell used for process print. To enable us to utilize a more durable lower line screen engraving, without sacrificing print cleanliness, it was necessary to also decrease the cell volume as we decreased the line screen.

Eight engravings were tested – 600 lpi – 4.0 bcm, 550 lpi – 3.8 bcm, 500 lpi – 3.6 bcm and 450 lpi – 3.4 bcm for combination print and a 900 lpi – 2.6 bcm, 850 lpi – 2.5 bcm, 800 lpi – 2.4 bcm and a 750 lpi – 2.3 bcm for process print. The end result was, by reducing both line screen and volume, all four engravings in each category produced nearly identical density and dot gain results. The advantage of utilizing the lower line screen and volume engraving is the cell surface is much smoother and it will transfer its volume more consistently.

Lower Your Anilox Line Screen and Cell Volume for Better Performance - LPI
The table above shows the results of the highest and lowest LPI for each application, please note the LPI, BCM, density and dot gain results for each.
 

In addition, Pamarco believes engravings used with steel doctor blades should be diamond film polished after engraving using a precision mechanical process. This process removes the nodules and creates a flat, smooth surface that is resistant to wear. All of our engravings used with steel doctor blades receive this process. In addition by utilizing lower cell count and volume ratios this process can be done with much more successful and repeatable results. Cell walls are flatter, smoother, and narrower, allowing for greater durability while insuring consistency in ink transfer and print performance.

The anilox’s “job” is to transfer a precise, predictable, and consistent ink film to the printing plate. The ink film is determined by the cell volume, not the line screen. It may be time to re-think the specifications of this import tool for greater long-term printing performance, consistency and durability.

For more information about Pamarco or for help acquiring the correct specifications for your anilox rolls, please call us at 1-800-53Flexo.

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Filed under Anilox Rolls, Printing

Pinning Technology for Clean Transfer

Pinning Technology for Clean Transfer is a unique plate technology engineered by Asahi Photoproducts to transfer all remaining ink to the print substrate due to the photopolymer plates having a lower surface energy than other plates on the market. Not only does this deliver stunning graphical quality, but it also improves overall production efficiencies due to reduced makeready waste and fewer press wash-ups.

Pinning Technology for Clean Transfer - infographic

Asahi AWP™ water-washable plates use Pinning Technology for Clean Transfer. This enables them to produce superior results compared to both traditional and digital flexographic printing plates. They also are a more environmentally sustainable solution. It should be noted that up to 15 litres of solvent per plate are used in the solvent-based platemaking process. The entire AWPTM plate manufacturing process creates little waste, just unexposed polymer residues and wash out solution, which are collected and safely incinerated.

In a recent controlled test comparing water-washable plates to standard solvent-based plates, results indicated operations could achieve in an immediate ROI when switching to these plates.

  • For the conventional plate, the run length was 37,368 linear metres. It took a total running time of 173 minutes. Total press down time was 47 minutes for plate cleaning and make-ready. Waste produced was 1,025 metres. OEE efficiency was calculated to be 72%.
  • For the Pinning Technology plates, the run length was 38,000 linear metres. It took a total running time of 140 minutes. Total press down time was 8 minutes for plate cleaning and make-ready. Waste produced was 450 metres OEE efficiency was calculated to be 91%.

Pinning Technology for Clean Transfer

Pinning Technology plates produced 575 linear meters less waste material. They resulted in a 26% improvement in overall equipment effectiveness (OEE) with fewer press stops for plate cleaning and more consistent overall quality. For a 24-hour operation, this translates to the ability to process at least two additional jobs per day at a higher quality level with more contrast and less environmental impact.

Pinning Technology for Clean Transfer - OEE AWP

The cost benefit of the AWP plate may vary depending on the customer’s production profile but is typically between 25% – 35% vs. conventional plate technologies.

Due to their exceptionally precise registration, plates with Pinning Technology for Clean Transfer also make it easier to implement Fixed Colour Palette printing to virtually eliminate the need for spot colour inks, reducing ink inventories and minimising or eliminating the need for press wash-ups between jobs.

Using fixed colour palette printing, the breakeven between flexo and digital printing continues to fall to as short a run length as 350 metres. This means that flexo is competitive with digital for all but the shortest runs, and there are many benefits packaging converters can gain by moving to this model, including very short job changeover times with minimal or no wash-up and limited waste due to the fact that inks do not have to be changed. Plus, more than 90% of Pantone colours can be accurately rendered using fixed colour palette printing.

Pinning Technology for Clean Transfer is an innovation in flexographic plate technology and a win/win for forward-thinking flexo printers.

View Pinning Technology Video

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Filed under Plate Technology, Printing

Addressing Metering Challenges of White Inks

by Daetwyler

White-Inks-Infographic

WHY ARE WHITE INKS DIFFICULT TO WORK WITH?

All professional printers eventually come up against the metering challenges of white inks. Throughout the industry, white inks are notorious for being inconsistent and requiring frequent changing of doctor blades often. The longer a doctor blade lasts, the more expensive it is in many cases. Weighing the cost of a doctor blade vs. the cost of press downtime is as issue printers and coaters deal with constantly. The issue with metering white inks is actually a little more complicated than just buying the right blade.

GATHER PROFESSIONAL SUPPORT:

First and foremost, ink, anilox, and doctor blade suppliers should all be consulted in a cooperative manner. When everyone knows the details of the scenario, a more comprehensive solution can be attained. Having end seal suppliers involved can also prove useful. Most people working in these industries are either printers themselves or have at least been involved in the print industry for some time – so they will most likely be able to relate to your specific challenges.

COMMON SENSE ANSWERS:

Having your press and chambers in optimum condition can provide big results. By taking care of the mechanical issue in order to optimize the setting of the chamber at the lowest amount of pressure possible, run times for both doctor blades and end seals can be significantly extended. By simply taking the extra 10-15 minutes to clean a deck and an extra 2 minutes to set it lightly and evenly, some issues may be completely resolved. It’s definitely worth investigating before moving on to more involved solutions. CAREFUL SET-UP AND MAINTENANCE: Maintaining the proper viscosity and ink/vehicle/solvent ratio is another very important consideration when it comes to working with white inks. Often, when issues come up with white inks, even though other printing functions have been problem-free for some time, viscosity and solvent ratios are a primary reason behind the problem.

In most cases radius tipped blades are used for any roller under 600 lines per inch (lpi). Switching to a radius tip blade from a lamella or bevel blade may help or eliminate many white ink challenges. Increasing the thickness of the blade may help as well. However, remember, the more steel you throw at the problem, the more it increases anilox wear – so proceed with caution. Many printers elect to use a coated blade to address the wear, quality and press downtime issue with metering white inks. These coatings are generally significantly harder than a standard doctor blade but not quite as hard as the ceramic anilox roller itself. Other ingredients in the coatings can help address coefficient of friction values (COF). These coated blades can greatly increase doctor blade wear but should also be installed in the chambers properly and care should be used setting them. They are significantly higher in cost, though proper care when using them can increase the return on your investment. In some cases, plastic blades have been used with promising results. While this has not proven to work across the board for consistent metering, it may be worth looking into.

Download the full White Inks White Paper for more information. 

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Filed under Doctor Blades, Ink, Printing

6 Factors of Maintaining Plate Quality

APR Logo

by Catherine Green, All Printing Resources

6-factors-plate-quality-800x800-300x300Platemaking is a science, not an art. While there is a bit of flexibility in specifications for different processes, there are defined parameters that must be followed if high quality plates are to be made consistently. In this article, we’ll discuss six important factors for making high quality plates.

1. Relief Depth

Relief depth is the difference in height between the printing surface and the floor of the plate. We can obtain this measurement by measuring the overall plate thickness, then subtracting the floor thickness.

There are recommended relief depths for different plate thicknesses:

Plate Thickness Ideal Relief Depth Max Relief Depth
0.045” (1.14mm) 0.018” – 0.022” 0.022”
0.067” (1.70mm) 0.018” – 0.022” 0.025”
0.112” (2.84mm) 0.020” – 0.025” 0.030”
0.250” (6.35mm) 0.050” – 0.070” 0.070”

2. Imaging Quality

Whether you’re using digital or analog plates, the finished plate cannot exceed the quality of the original image carrier. If you’re making analog plates using film, confirming proper film density (over 4.0) is critical. With digital plates, the digital imager must to be checked for correct focus and power settings periodically (every 4 to 6 weeks, or any time the laser head is contacted by a loose plate). These tests can be done yourself with the proper tools and training, by your digital imager supplier, or by APR’s TSG group.

3. Exposure Conditions

Plate exposure units contain two types of UV bulbs: UVA bulbs (for back, main, and post exposures), and UVC bulbs (for light finishing). For maximum plate quality, these bulbs must be monitored and replaced at the end of their useful life. While extending exposure times to make up for weak bulbs can work in a pinch, this tactic sacrifices plate quality. Longer exposure times can lead to broadening of the plate’s shoulder angle, resulting in dot gain and filling in of fine reverse detail (especially with analog plates). In addition, the plate room environment should be kept clean and free of dust to prevent any unwanted debris from contaminating the plate before or during exposure.

4. Polymer Saturation

Both solvent and aqueous platemaking use liquid to wash away the unexposed photopolymer in the plate’s non-printing areas. This liquid, whether a hydrocarbon solvent or water, will eventually become contaminated with dissolved polymer solids. The level of saturation, or percent solids, can have a dramatic effect on both plate quality and equipment maintenance. In solvent platemaking, it’s recommended to keep the concentration of solids below 6% to ensure optimum plate washout and keep equipment maintenance to a minimum. If the solids are allowed to collect above this level, the result can be increased washout time, which results in a longer dwell time in solvent for the plate, culminating in a longer drying time. Extensive cleaning may also be needed to remove excess polymer buildup throughout the system. In aqueous platemaking, weekly solution changes and machine cleanings are key to trouble-free operation. Since aqueous polymer doesn’t dissolve completely in water, there is a chance that small particles of polymer could re-deposit onto the plate if they are not removed from the system. It is essential that these machines are kept clean and proper filtration is used to manage the washout solution. The exception to this rule is thermal plate processing. Since thermal processors utilize a one-time-use wicking media to remove the uncured photopolymer, there is no polymer saturation to monitor– only the amount of wicking media remaining in the machine.

5. Drying

One of the most important, yet most overlooked factors in solvent plate quality control, complete drying is crucial to consistent platemaking. Incomplete drying can be caused by a number of factors including early removal of the plate from the dryer, inadequate dryer air circulation, and improper drying temperature. To check a solvent plate for complete drying, remove the plate from the dryer and allow to cool for 5 minutes. Next, measure the overall plate thickness with a micrometer. The plate should be no thicker than 0.001” – 0.002” over the original plate gauge (be sure to measure the original gauge on a sheet of raw material). When plates are not completely dry, they remain swollen from absorption of solvent. This can lead to problems on press including poor registration, over-impression, and decreased plate life.

6. Plate Handling

Good plate handling and storage practices can save time and money with both press downtime and plate remakes. Plates should always be handled with care, and treated as a fragile component of the printing press. Never place objects on top of plates, fold/crease plates, or expose plates to unknown chemicals. Plates can be only be stacked flat when foam or parchment paper is placed between them to prevent direct contact. Environmental factors that can harm printing plates include exposure to room light or sunlight, and storage near ozone-producing equipment (most common offenders include: HVAC and electrical equipment). To ensure maximum plate life, used plates should be cleaned as soon as they are removed from press using an approved cleaner and a soft horsehair brush. Another great option for plate cleaning is an automated plate cleaning machine. These simple machines make quick work of dirty plates, produce consistent cleaning results with minimal labor, which streamlines the post-press workflow and makes the most of valuable employee time.

By following these simple steps, you will ensure that your platemaking and storage is as efficient and effective as possible.

For more information regarding products or procedures mentioned in this article, contact Catherine Green of APR’s Technical Solutions Group (c.green@teamflexo.com).

About the Author:

Catherine-Green_200Catherine Green – Catherine has over 12 years experience in graphic arts. An honors graduate of Clemson University’s Graphic Communications program, she has held positions in prepress, platemaking, and technical support. Before joining APR’s Technical Solutions Group, Catherine worked for Asahi Photoproducts as their Technical Specialist for North America. She brings expertise in digital platemaking, prepress, and process improvement to the TSG. She is an active member of the FTA, serving on both the Excellence in Flexography judging panel and FQC groups.

About All Printing Resources, Inc. (APR)

All Printing Resources, Inc. (APR) is a proven resource for solutions, trusted service, and support to the flexographic printing industry. APR delivers measurable performance enhancements and total cost reductions, including the after sale attention needed to see optimal results. APR represents some of the most innovative product lines worldwide and takes a “team” approach to deliver process improvement and innovative solutions.

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Filed under Plates, Prepress, Printing

Who You Gonna Call?  Ghost Hunting in Flexographic Printing

Apex International Blog

by Doug Jones, Apex International

Ghosting, a faint image from another part of the design that appears where it shouldn’t, has always haunted the flexo industry.  Ghosting is most obvious in areas where large solids are used and always on printed side of substrate in the image area.  

ghosting-image

What causes ghosting?

Fortunately, the cause is far from supernatural.  While much has been written on the subject, most agree on these six issues as the most likely causes of ghosting.

  • Ink starvation
  • Ink fluidity is not appropriate
  • Chambered doctor blade not adapted
  • Mechanical issue
  • Anilox roll is not properly cleaned
  • Premature drying of ink on the anilox roll

What can I do?

Leave the Proton Pack at home!  The next time you have an issue with ghosting, try working through each of these possible solutions.

  • Increase ink level and/or pressure into the chambered doctor blade.
  • Use higher anilox roller volume
  • Add solvent (retarder) to increase ink fluidity, to flood the cells, and avoid ink drying into cells
  • Use a specific design of the chambered doctor blade to force ink to flood the cells
  • Select anilox roller where the circumference is a whole number multiple of the repeat length of the design times the number of plates round the cylinder or change the diameter of the plate cylinder
  • Increase the speed of the machine

Download the Flexographics Solutions Guide

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Filed under Print Defects, Printing

Are Your Doctor Blades Due for a Checkup?

APR Logo

by Catherine Green, All Printing Resources

In flexography, print defects can stem from a multitude of moving parts, making troubleshooting feel like a constant game of chase. Much like the human body, with proper care and maintenance, all parts of this highly complex system can work together in harmony.

While the anilox roll is the heart of the printing press, the doctor blades are the workhorses that let the anilox do its job properly. Without even, consistent ink metering, the anilox is unable to deliver a uniform, measured ink film to the printing plate surface– its primary (and only) function. Ensuring your doctor blades are set properly in the press can make or break your printed result.

Doctor Blade Pressure

By inspecting the contact patch surface, information can be gathered to determine if the blade pressure across the chamber is set evenly. Uneven blade pressure can be due to misaligned chambers or incorrect installation of the doctor blade into the blade holder. Also, contaminants in the ink can leave behind score lines in the blade, or worse, the anilox roll. Looking for these clues and correcting the issue with proper ink filtration can prevent anilox refinishing and costly press downtime.

Installation of the doctor blade into the holder is easily one of the most commonly overlooked factors in the process. If the blade is installed incorrectly, it is nearly impossible to achieve proper ink metering. Doctor blades should always be installed into a clean holder, completely free of ink residue or other debris. When placing the new blade into the holder, ensure the blade is fully seated, then secure the blade from the center, working your way out to the ends. Following this simple procedure will ensure you’re starting a straight and true blade with each changeover.

This photo shows the precise measurement of a used doctor blade’s wear angle. (Click image to enlarge.)

This photo shows the precise measurement
of a used doctor blade’s wear angle.

If the press uses a chambered system, you’ll need to ensure the end seals fit properly and the blades are in the proper position in relation to the end seal. Check the fit of the seal in the chamber by looking for any gaps or excess compression around the seal. Also be sure that the anilox radius is an exact match to the anilox used on press. The fit should always be snug and accurate. To further prevent leaks, ensure the doctor blade overlaps the end seal halfway.

Once the blades are properly installed, the correct blade pressure is set, and the press is up and running, how can we know everything is performing as expected? This is where doctor blade analysis comes in. By carefully analyzing the used blades (both metering and containment, where applicable), APR’s Technical Solutions Group can pinpoint issues such as improper blade angles, poor blade mounting, or uneven chambers. This can be quite helpful when troubleshooting an existing problem, setting up a new press, or testing doctor blades.

To schedule a doctor blade trial or find out more about our analysis services, contact Catherine Green at c.green@teamflexo.com.

About the Author:

Catherine-Green_200Catherine Green – Catherine has over 12 years experience in graphic arts. An honors graduate of Clemson University’s Graphic Communications program, she has held positions in prepress, platemaking, and technical support. Before joining APR’s Technical Solutions Group, Catherine worked for Asahi Photoproducts as their Technical Specialist for North America. She brings expertise in digital platemaking, prepress, and process improvement to the TSG. She is an active member of the FTA, serving on both the Excellence in Flexography judging panel and FQC groups.

All Printing Resources, Inc. (APR) is a proven resource for solutions, trusted service, and support to the flexographic printing industry. APR delivers measurable performance enhancements and total cost reductions, including the after sale attention needed to see optimal results. APR represents some of the most innovative product lines worldwide and takes a “team” approach to deliver process improvement and innovative solutions

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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!).

ShallowCells_GTT

  • 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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