Considerations for selecting the right doctor blade: An Interview with the CEO of Flexo Concepts

July 7, 2022 Over the years the print industry has continued to innovate with the rise of digital printing, new ink systems and advances in packaging. With all of these printing innovations come additional considerations for pressroom operators, including the many factors involved in choosing a doctor blade. To help navigate the blade selection process we sat down with Kevin McLaughlin, doctor blade expert and CEO of Flexo Concepts. What do you see as some of the most discussed topics in pressrooms today?

Certainly, the answer to that question has changed over the years. Early in my career, there were a lot of conversations around print quality, extended gamut printing and how to improve process printing. Today the conversations we have the most with customers are really wrapped around labor availability, the inexperience of the labor available in the pressroom and safety. In many ways, inexperienced labor and safety are related. If you have younger or more inexperienced operators safety becomes a bigger issue. What issues do you see as we push presses faster that we would need to address with a doctor blade system? What are some key considerations for operators when running presses at high speeds?

The faster you run the press,

the more important everything else becomes — whether it’s doctor blade related, ink-related, unwind or rewind-related. With regards to doctor blades, some of the small considerations become extremely critical. Is your chamber aligned? Did you cut the doctor blade to the right length so it sits over the seal properly? What blade pressure do you have? Are you able to run the press with minimal blade pressure? Those issues, while always important, become hyper-important as press speeds increase.

Another area is ink temperature, which is uniquely important and relates to doctor blade issues. Anytime the ink moves through a system, whether it is a line, the chamber or a pump, energy is imparted on the ink and heat is generated. When the doctor blade contacts the anilox roll at high speeds frictional heat is generated. Being able to minimize that frictional heat through light blade pressure and potentially your doctor blade selection will be a benefit at high speed. In addition, being able to chill and maintain the temperature of the ink at those high speeds is a real issue for high-speed printing.

Operators traditionally try to minimize the doctor blade costs, but the cost of the blade is not the most critical factor to consider, as high-speed printing is only valuable if the press is running. Doctor blades are an area that you really should be investing in whether it is in steel blades or polymer blades.

Traditionally plastic doctor blades were not an option for high-speed printing. Even today, it is not an option regularly because the frictional heat that is generated between a blade and an anilox roll can accelerate the creep curve on a plastic doctor blade, which causes the blade to lose force under a fixed load. So traditionally, if a press is running more than 1200 feet per minute (about 365 m) I would not recommend the use of a polymer blade.

With that said, the traditional use of doctor blades is changing. Flexo Concepts has a polymer blade called TruPoint KEON, that performs well in a high-speed application running 2600 feet (about 792 m) per minute. We also have a new polymer doctor blade we are developing which is in beta testing right now and was developed in our Innovation Lab. This is a polymer blade which will be an option for high-speed printing presses running at similar speeds.

What advice do you have for operators trying to choose the right doctor blade for their application?

First and foremost keep an open mind. I think that, ideally, you are picking the right blades for the right application. That can include mixing and matching doctor blades. The goal is to optimize for your print job because different applications require different blades. Whether that’s material, blade thickness or tip configuration, keep an open mind. For instance, if you are looking at highline process printing you would want a thinner contact area which would be achieved with a thin plastic blade with a Microtip or a thin steel blade. However, if your printing job includes some sort of OPV, soft-touch coating or glitter coating, a thicker plastic blade with a bevel or a large microtip would provide better performance. It is okay to have both of those blades on the same job, so keep an open mind and really try to optimize the blade for your application.

Certain factors play a role and are important considerations when helping you decide the right doctor blade for your application. What is your anilox roll configuration? What types of ink are you running (UV ink, electron beam, solvent or water-based)? Are there any special temperature issues? Is a two-part catalyzed ink or coating being used? Are there any special solvents? Is this a positive or negative angle application? All those factors are important for us to know to help pressroom operators select the right doctor blade for their application.

Are there instances where you should not use a TruPoint Orange doctor blade?

A lot of press operators want a simple answer, but if you simplify by using the same doctor blade for all your press runs and applications you end up giving up something. That something could be blade performance or blade life. So, by being open to using more than one type of doctor blade on your press you do not have to give anything up, you can optimize the job that you are running.

Within our TruPoint portfolio, we have a variety of doctor blade products. Some of them are assorted colors and each blade has distinct characteristics. Steel blades are appropriate for a lot of applications as well. The important thing is really understanding the need and the application and then applying the right doctor blade.

What exciting innovations can we expect from Flexo Concepts this year?

Innovation is a key part of Flexo Concepts. We committed a few years ago to building an in-house innovation lab that is dedicated to product innovation and staffed with full-time employees whose only job is working on our next-generation products. Over the last 8 years we have launched four new TruPoint products, some blades are used for flexographic printing, narrow web, digital printing, coating and OPV applications. One TruPoint Green is a doctor blade for corrugated applications.

In 2022 we are launching two new products and we expect a third to be ready for launch in 2023 or early 2024. All of these new products will address needs in the flexographic printing market as well as specialty coating applications.

Innovation is more than just product innovation; it is really an organizational philosophy. One example is our digital transformation. Over the last five years we have completely digitally transformed Flexo Concepts and taken out every analog process in our plant. Our manufacturing facilities are paperless. From quote to cash there is only one piece of paper that is generated and that is a packing list. It creates better efficiency, it is better for the customer and it helps us improve our quality systems, so this is part of being the most innovative doctor blade company in the industry.

Another area of innovation is how we engage our customers. The most recent innovation is our FC marketplace, which is an online portal for existing TruPoint customers. They can determine pricing for products without calling in. They can place their TruPoint orders online, view previous orders, build a shopping cart, track orders moving through the system and submit quality cases. Anything that they previously had to engage a customer service person for they now have control at their fingertips to do it themselves.

Selecting a doctor blade is a complicated process. Selection should not be based on just one factor and choosing the cheapest doctor blade will not give you the best results. To really understand which blade is best for your press, it is important to understand your current pain points and the print outcome that you are trying to achieve. It is important to consider print quality and to optimize your press for speed and temperature. There is no one size fits all, and various blades can be used for various applications.

To learn more about Flexo Concepts and how to optimize your press, visit www.flexoconcepts.com to receive a free consultation.