FTA Flexo Magazine features Rheonics FTA Technical Innovation Award winning Technology – “Excellence via Viscosity Control”

July 30, 2021
Publications

Overview

Flexographic printing focused magazine – Flexo (https://www.flexography.org/flexo-magazine/) publishes an in depth article showcasing the Rheonics SRV viscometers and the RPS InkSight Multi-Station Ink Control solution and how it enables excellence in color control in printing.

Find the link to the publication.

Flexographic Technical Association – Flexo Magazine Feature (flexography.org)

To download the pdf copy of the article, please use the link below.

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Engagements in LinkedIn and Facebook channels,

LinkedIn post by FTA

Facebook post by FTA

Introduction

A LOOK INSIDE RHEONICS’ FTA TECHNICAL INNOVATION AWARD-WINNING INKSIGHT

A central goal of flexographic printing is to produce the best possible print quality, most economically. In today’s brand conscious market, high print quality is of paramount importance in attracting customers and maintaining a loyal customer base.

ColorLock locks in the initial match of the printed color to the master; InkSight ensures this match is maintained over the entire printrun, no matter how long, and no matter how many times fresh ink must be added.

Topics Covered in the article

Goals of flexographic printing
Color & viscosity control
Viscosity control is the key
COLORLOCK Software
InkSight in use

Some figures from the article

Figure 1: Color density variation with ink dilution and viscosity

Figure 2: Delta E 2000 values as a function of ink viscosity (referred to a digital PMS reference)

Figure 3a: ColorLock interface screenshot (top) showing 8-station press with six stations active

Figure 3b: Loading a pre-existing job for repeat run

Figure 4: Inline viscometer, a Rheonics SRV

Figure 5: Two SRV inline viscometers installed on the ink hoses from pump to the doctor chamber

Figure 6: (a) InkSight predictive tracking controller

Figure 6(b): W&H Primaflex CS 8-station with InkSight system integrated in the press as a modular unit

Figure 7: Inksight Colorlock HMI co-located with the main press console

Figure 8: Startup process showing fast, autonomous stabilization of ink viscosity to set point

Figure 9: Response of InkSight system to addition of fresh ink during a
run—within five minutes, the system brings freshly added ink to operational
viscosity setpoint

Figure 10: (a) Delta E 2000 for a run of 24,500 meters spread over five days and 13 reels

Figure 10(b): Sample of print

Unique advantages with the Rheonics SRV sensors

Rheonics sensors have built-in temperature measurement, permitting the temperature of the ink to be monitored. This permits the viscosity readings to compensated for temperature, which is essential for ensuring consistent production through typical daily and seasonal temperature variations.

There are many benefits to using an inline viscosity sensor like the SRV for printing applications. and some include:

Works accurately in most coating systems with a broad range of ink compositions and viscosities – water-based, solvent-based, UV inks, metallic inks etc.
Maintains the set ink viscosity, extremely responsive to fresh ink additions
Rugged, hermetically sealed sensor head. The SRV can be cleaned inline with all standard CIP processes, or with a wetted rag, without the need for disassembly or recalibration
No moving parts to age or foul with sediment
Insensitive to particulate matter; no narrow gaps to foul with particulates
All wetted parts are 316L stainless steel—meets sanitary norms with no corrosion problems
Certified under ATEX and IECEx as intrinsically safe for use in hazardous environments
Wide operational range and simple integration—Sensor electronics and communication options make it extremely easy to integrate and run in industrial PLC and control systems.

Some images of the RPS InkSight system

Rheonics SmartView console integrated in printing machines
Some pictures showing the SRV viscometers inline installation inside the press
Standalone control cabinet

Viscosity Standardization in Flexographic Printing

In the history of our company we have applied every type of viscosity sensor: rotational, falling ball, falling piston and acoustic wave. The similarity between these sensors is that they are all calibrated with a cup, in our case the DIN cup with a 4 mm outlet. In itself this worked well and due to lack of a better alternative…

Optimizing flexographic, gravure and corrugated printing applications through inline viscosity monitoring and control

Printing presses have numerous applications – newspapers, magazines, catalogues, packaging and labels. The global printing industry is forecast to reach $980 billion by 2018 according to market research firm Smithers Pira. The rapid growth is expected to be driven mainly by the growth in packaging and labels – analog printing for packaging is expected to grow by about 28% and…

Rheonics products portfolio for printing companies

All Rheonics products are designed to withstand harshest process environments, high temperature, high level of shock, vibrations, abrasives & chemicals.

RPS InkSight

Multi-station in-line ink monitoring & control system

SRV

Wide-range inline fluid Viscometer

Conclusion

As printing speeds increase, and profit margins get tighter, “getting it right the first time” becomes much more important. An error in initial viscosity setting can result in producing several thousand meters of waste in no time at all. Tight control with an accurate sensor, combined with a responsive control system, has enabled us to streamline our printing process while improving color quality and reducing waste.

What is unique about Rheonics viscosity control?

Traditional viscosity measuring methods (like efflux cups) are inaccurate, tedious to use, and prone to errors. Continuous viscosity control with such methods is extremely inefficient and unproductive.
Many common viscosity measuring devices do not provide fine enough viscosity control and require high maintenance and frequent calibration.
Rheonics RPS InkSight Predictive Tracking Controller and SRV viscometers enable tight viscosity control throughout the print job, due to the the system’s ability to autonomously maintain viscosity within extremely narrow limits.
Printers can achieve unmatched color accuracy and quality with the RPS InkSight system and ColorLock software – which is designed in collaboration with printers, for printers.