Guidelines for Using DigiPrime® Icon for Off-Line Coaters

Michelman’s DigiPrime® Icon brand of primers, designed for converters who prepare substrates off-line, provides several performance advantages including better runnability, cleanability, lower odor, and superior adhesion.

The primers, which are press-ready, water-based, and designed for flexographic or gravure applications, optimize most film and paper substrates. They are very stable in liquid form, with a shelf life of 12 to 24 months if stored unopened at moderate temperatures. Coated substrates have a shelf life of 12 months or more and will not yellow or show degradation of print quality or adhesion.

These guidelines are applicable for DigiPrime® Icon 8000, DigiPrime® Icon 8010, and DigiPrime® Icon 8020.

Substrate Selection

  • Paper that is uncoated, matte, semi-gloss, and/or cast-coated.
  • Film that has a surface energy of 42 dynes/cm or more.

Corona Treatment & Refreshment

Corona treatment is recommended when using film, not only to keep control of the surface energy, which needs to be above 42 dynes/cm to achieve optimum wet-out and full adhesion, but also to refresh the film even when it is above 42 dynes/cm. Use a dyne pen or dyne solution to check the corona level before priming.

Application Preparation

Clean the coating system thoroughly by flushing the supply lines and pumps with clean water, then cleaning the coater pans and rollers. Many ink or water-based primer chemistries used in the conventional printing industry can be incompatible. Do not use solvent-based cleaners. DigiPrime® primers will react negatively, becoming very viscous and dense.


A minimum web temperature out of the dryer/oven between 45-60°C is required to obtain full adhesion after drying. The web must cool to less than 30°C before rewinding the roll to prevent blocking. It is essential to have good drying in order to stock the primed reels in the right condition. Primed reels are equipment that should be appropriately stored, until printing, in a cart where the reels can be hung or placed vertically. Both ways eliminate the pressure on the primed reels, avoiding their possible blocking and deformation. Proper drying is critical for adhesion, block prevention, and correct end specifications.


DigiPrime® primers should be stored in an area above 5°C and protected from freezing. Do not use if grit or gels form due to low temperature.


Although press-ready, DigiPrime® off-line primers can be diluted with deionized or soft water. Adding more than 20% weight of deionized water will change viscosity and solids content and alter the performance of the coated substrates.

Application and Cleaning

DigiPrime® off-line primers should not be allowed to dry on the anilox. Keep the coater moving, rollers turning, and surfaces wet. Water or water/soap mixture is the preferred method for clean-up, but the following suppliers also offer suitable cleaners:

In der Fleute 18
42897 Remscheid
+49 (0)2191 969 0
Flexoclean Engineering .B.V.
Bliek 8
4941 SG Raamsdonksveer
The Netherlands
+31 (0)162 576 222
BicarBlast B.V.
Sigarenmaker 2
5521 DJ Eersel
The Netherlands
+31 (0)497 33 00 32
Danko Industries
181 Wolf St #C
Yorkville, IL 60560, US
+1 630-882-6070


Coat Weight

The recommended target coat weight of DigiPrime® on most surfaces, undiluted, is 1-1.5 gsm wet. However, depending on the absorbency or texture of a surface, higher coat weights may be needed and should be established by experimentation. Excessive coat weight may result in blocking the wound roll, and coat weight that is too high or too low may result in a lack of adhesion. Verify the coat weight and apply the primer according to substrate type.

Substrate Selection

Quality primer adhesion involves combining Michem® Indicator 001 with a tape test:

Materials and process for quality ink adhesion include:

86% of the ink adhesion should be achieved after 15 minutes.
(3 Star HP Indigo Media Certification)

Monitoring Coat Weight

Monitor the use of DigiPrime® off-line primers over a known length and width of media:

Gravimetric Method: Checking coat weight on plain films can be achieved by measuring the weight difference. Obtain an accurate balance because of the very low dry coat weight.

Recommended Coat Weight

SubstrateTarget Wet GSMAnilox Lines per InchAnilox Lines per CMCell Volumne BCMCell Volumne CC/M2







Uncoated Papers






Claycoated Papers






Primer Specification

Off-Line PrimerSubstrateApplicationFood Contact

DigiPrime® Icon 8000

uncoated, mottled, semi-gloss, and high-gloss paper

general purpose paper


DigiPrime® Icon 8010

uncoated, mottled, semi-gloss, and high-gloss paper, PE

high-gloss paper


DigiPrime® Icon 8020

general paper and film

flexible packaging and labels


Published on: May 4, 2023