Ph: 1 2357 Fax: 1 ESA … Impression Roll Unique Advancement tions. This technology is now licensed...

ESA Impression Roll Unique Advancement

For Use With Gravure

Presses from… Bobst

Cerutti

KBA/Frankenthaler

Kochsiek

Rotomec

Schiavi

Giave

ATN

W-H

Fischer-Krecke

For Use With ESA

System Suppliers… Hurletron

Spangler

Eltex

Crosfield-QuadTech

Enulec

For all ESA Configs… Top Load

Side Load

Core Charged

A proven and unique polyurethane technology that provides an exceptionally uniform level of conductivity across the roll face. Unlike conventional rubber based ESA impression rolls, the con-ductivity remains virtually the same over the life of the roll.

Improvement in Print Quality

Dramatic Increase in Roll Life

©2004, 2005, 2006 Graphic Printing Roller Ltd. All Rights Reserved.

This unique material in the polyurethane family is inherently tougher and more durable than other polyurethane impression rolls and an extraordinary improvement compared to rubber ESA impression rolls. These are proven in worldwide installa-tions in Publication, Packaging and Decorative printing applica-tions. This technology is now licensed in North America exclu-sively to Graphic Printing Roller Ltd.

ESA Technology

Graphic Printing Roller

Graphic Printing Roller 6-343 Rodick Road

Markham, Ontario, Canada L6G 1B1

www.graphicroller.com Ph: 1-800-265-7418 1-905-475-2357 Fax: 1-905-475-3421

ESA PUR Impression RollWhat’s Unique about ESA PUR?

Key Benefits

Stable electrical conductivity over life of roll cover

Uniform electrical conductivity across roll face

Stable roll hardness over roll life

Lower nip pressures often needed

Longer impression roll life from exceptional wear resistance

Reduced forces on roll shafts from

lower nip pressures

Reduced bearing wear from reduced roll pressures

All rubber ESA impression rolls are subject to conductivity creep. Shortly after installation and operation in your gravure press you likely notice a decrease in conductivity (an increase in resistance). This of-ten requires changes to the ESA voltage settings to reduce the impact on print quality.

Rubber ESA impression rolls obtain their conductivity from semi-conductive rubber and conductive fillers like carbon black and con-ductive metal powders. The electrical conductivity of this type of rub-ber compound occurs through a “mechanical molecule chain”.

Continuous operation of the impression roll nip creates micro-fractures in the conductive mechanical chain. Over time, these micro-fractures or breaks in the mechanical chain create miniature “open circuits” in the electrical path. This leads directly to conductivity creep. Operators then adjust voltages or impression roll pressure to attempt to maintain print quality.

If the conductivity remained relatively stable over the life of the roll, your print quality would be consistent and your operators would only use the pressure necessary to achieve the print quality for that volt-age setting.

ESA PUR is a unique, patented roll technology developed and in-stalled throughout Europe. ESA PUR achieves uniform conductivity over the life of the roll using “chemical molecule chains”. Roll conduc-tivity remains virtually the same over the life of the impression roll and the conductivity across the entire impression roll face remains very consistent– a key factor in cross-direction print consistency.

Gravure press operators discover they may achieve the same or better print-ing results using the ESA PUR im-pression rolls while lowering their volt-age requirements and lowering their impression roll pressure.

Consistent and Stable Conductivity


ESA Technology

Graphic Prin�ng RollerGraphic Printing Roller

6� 343 Rodick RoadMarkham, Ontario, Canada

L6G 1B1www.graphicroller.com

Ph: 1� 800� 265� 7418 1� 905� 475� 2357 Fax: 1� 905� 475� 3421

ESA Impression Roll

Technology Advancement

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Features and Benefits

Sector Product Name Material Type Hardness Range Key Characteris�cs

Publica�on IRP-6460 ESA PUR

Polyurethane

65-89 Shore A Abrasion resistance 2.5x higher

than rubber . Cut resistance 1.5x

higher than rubber. Stable and con

sistent electrical proper�es over

the en�re roll face.

Packaging IRP-6462 ESA PUR

Polyurethane

65-89 Shore A Abrasion resistance 2.5x higher

than rubber . Cut resistance 1.5x

higher than rubber. Stable and con

sistent electrical proper�es over

the en�re roll face.

Decora�ve IRP-6468 ESA PUR

Polyurethane

65-89 Shore A Superior abrasion resistance 4x

higher than rubber. Cut resistance

2x higher than rubber.

Stable and consistent electrical

proper�es over the en�re roll face.

Each of the above materials makes wear of the roll cover at the edges of the web prac�cally non-existent enabling web width changes without first having to regrind the roll! Excep�onally low heat

build-up and low vibra�on.





Ph: 1� 800� 265� 7418 1� 905� 475� 2357 Fax: 1� 905� 475� 3421

ESA PUR Recommenda�ons, Handling, Grinding & Cleaning Procedures


Cleaning with solvent can temporarily result in increased surface resistance values. 2 hours after cieaning however, normal values should be restored

Recommendations for ESA PUR Polyurethane Impression Rollers

Gravure impression rollers made from polyurethane materials have gained wide acceptance in rotogravure installations throughout the industry. For ESA applications, electrically conductive PUR-materials are used. They differ in operation and maintenance requirements than conventional ”rubber“ impression roll covers. This has to be considered by a printer using PUR– impression rollers. The unique and patented nature of our ESA PUR impression roller provides better printed results and longer life between impression roll changes than available in the North America.

Selection of PUR � Quality

Depending on the kind of gravure printing (magazine, packaging, decor, etc.) and the type of printed material, the correct PUR quality has to be selected in a hardness, ranging from 65 to 90 Shore A.

Because of the entirely different elastic behavior of PUR, compared with rubber, experiences with rubber covers are not necessarily the same as encountered with polyurethane. For instance, the elasticity of PUR is much higher than rubber, within the same hardness range.

Specialists at Graphic Printing Roller can assist you in selecting the correct polyurethane roll covering.

ESA PUR � Impression rollers from Graphic Printing Roller used for ESA gravure printingBecause of the unique benefits the ESA PUR roll cover, impression roll pressures can often be substantially reduced. Roll pressures of 60 PLI (10 N/mm) often provides satisfactory printing results. Using a lower roll pressure helps to reduce energy consumption and increases the service life of the impression rollers without sacrifycing printing quality.

The necessary “printing width/nip“ should be adjusted by selecting the proper cover hardness, instead of using historically high roll pressures. Linear pressure should not exceed 85 PLI (15 N/mm).

The special electrical properties of the ESA PUR roll coverings often allows a voltage reduction of the ESA-equipment, while achieving good printing results. This is compared with polyurethane or rubber covers. The necessary power setting has to be defined by the printer through tests, and can be 50 - 75 % of comparative values of rubber covers.

If in doubt and if using the ESA PUR covers for the first time, it‘s adviseable to consult the supplier of the ESA equipment or your technical representative at Graphic Printing Roller..

Cleaning of ESA PUR � Impression roller from Graphic Printing Roller

Graphic Printing Roller’s ESA PUR covers are very stable in conductivity, even in the machine under operating conditions.

As a result of the ESA-performance however, fine paper dust and ink color particles can accumulate on the cover working suface. This can lead to increased ”surface resistance values“. This may happen particularly when heavily coated papers or papers of “lower quality“ are used.

Together with the electrodes, etc. of the ESA equipment, ESA PUR covers and end faces need to be cleaned periodically. If the roll cover needs minimal, simple cleaning with a cloth a printing solvent can be used (eg. Toluol).

Cleaning of ESA PUR covers should be done at least once a week, depending on the cover‘s condition.Cleaning with solvent can temporarily result in increased surface resistance values. 2 hours after cleaning however, normal values should be restored.




Ph: 1� 800� 265� 7418 1� 905� 475� 2357 Fax: 1� 905� 475� 3421

ESA PUR Recommenda�ons, Handling, Grinding & Cleaning Procedures


Grinding of ESA PUR covers

In the case of extreme build-up of ink or paper dust, cover surface resistance values may rise to an extent, that cleaning only is not sufficient to restore ”normal“ values.

In practice, increases of up to 50 Megaohm do not affect the printing quality in most of the cases.

Unlike rubber ESA impression rolls, ESA PUR polyurethane covers do not require frequent regrinding. By kiss-grinding 0.020” to 0.040” from the diameter (0,5 � 1 mm in Ø), original electrical and mechanical values will be achieved again. This circumstance should be also used as a control measure - restoring original electrical values.

In case of frequent changes of web widths and by continuous contact with solvent, the ends of the covers tend to increase slightly in diameter. This can affect printing quality. If so, kiss-grinding is recommend as well.This fact is important, as it enables to regrind/equalize ESA PUR covers many, many times.

The interval between each kiss-grind can vary from machine to machine. lt should be established by each printer, based on the proper experience and requested printing quality. In that instance, a ”preventive“ grinding schedule is recommended.

Grinding conditions for ESA PUR covers are somewhat different than for ”rubber“ rollers. If machining is done improperly, the cover surface may melt. Please consult our instruction sheet ”Machining of polyurethane covers“.

Storage of ESA PUR covers

Rollers, taken out of a machine, should always be supported on its pivots. A prolonged storage on the elastic roller cover may cause slight permanent deformation. This will negatively influence future use.

For prolonged storage, the pressure roller should be kept in a dry room (max. 60% r.h.) at normal room temperature (20-30 °C) and protected from UV-Iight.

Graphic Prin�ng Roller Graphic Printing Roller



Ph: 1� 800� 265� 7418 1� 905� 475� 2357 Fax: 1� 905� 475� 3421

Ph: 1 2357 Fax: 1 ESA … Impression Roll Unique Advancement tions. This technology is now licensed...

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