EB curing: advanced liquid resin solutions for coatings, inks and adhesives

Electron beam (EB) is a low-VOC, solvent-free technology that provides enhanced properties for coatings, inks and adhesives industries. Arkema develops advanced liquid resin solutions and works with customers to formulate next-generation EB curable materials, increase efficiency and improve their time to market.

Radiation curing: from photos to electrons

	UV	EB
Form of energy	Photon	Accelerated e-
Range of energy	200 to 415 nm	80 to 300 kV
Total applied energy	0.5 J/cm²	20 to 40 kGy
Penetration depends on	Optical density of the material	Mass density of the material
Penetration control	Peak irradiance (power and focus) of the UV source	Acceleration voltage of the beam
Easily penetrates	Clear materials	Clear, pigmented, filled and opaque materials

Why use electron beam curing?

Benefits of EB Curing:

In addition to the lower energy-consumption benefits of radiation curing technologies,

No photoinitiators required ➞ minimized and low migration
High degree of conversion
Very high speed achievable allowing deep penetration for thick coatings
N₂ atmosphere needed to avoid O₂ inhibition
High energy radiation
Improved dot gain control
No heat for sensitive substrates
High performance: gloss, scuff and abrasion resistance
Suitable for highly pigmented formulations

➔ CURING OF THICK AND OPAQUE FILMS

➔ LOW RISK OF MIGRATION

Principle of the technology

Inside an ultra high vacuum chamber, an incandescent filament generates electrons. Then, the electrons are accelerated by a strong electrical field and exit the chamber through a thin titanium window.

Two variables matter particularly, the intensity (number of electrons generated per second) applied to the filament and the tension applied to accelerate these electrons.

Key parameters

The key parameters

With the EB curing technology, there are two key parameters that you can tune separately and independently from each other :

The dose (kGv) influences the flow of electrons: raising it is equivalent to increasing the number of electron hitting a certain surface area
The energy (kV) influences the penetration depth: increasing the energy is equivalent to amplifying the power of electrons that penetrate into the surface

Interaction with matter

Let us imagine an electron penetrating an acrylate monomer/oligomer formulation to approach the interaction with matter.

An electron comes from the top, some collisions occur while penetrating the substrate. That the results of energy generation, the electron loses his energy along the trajectory and this energy is deposited in the matter.

The energy is high (or the coating is thin), the electron goes all the way through the substrate
The energy is low (or the coating is thick), the electron is absorbed by the matter

When the energy is deposited (red crosses), secondary slower electrons (blue circles) may be generated; they are slower than primary electrons.

Initiation mechanism

The low speed secondary electrons produced are solvated by the acrylate and allows the formation of a radical anion. Then, the protonation (coming from impurities or traces of water) of this radical anion generates a free radical species. A free-radical initiated specie is produced and allow the polymerization start.

Thus, a primary electron generates many free radicals that will initiate the polymerization reaction. The higher the primary electron energy is, the more free radicals are generated.

Full service support for your projects

We can provide a unique service offering to help prospective customers perform feasibility studies in our lab. We combine deep know-how in (meth)acrylate chemistry with state-of-the-art laboratory equipment, to help you enhance the performance of EB curing in your existing applications, or test and develop proof of concept of new ideas.

Our lab service :

EBLab machine from 80 to 200 keV, format A4 up to 30m/min

Formulation lab and access to the whole Sartomer® product portfolio

Technical support and expertise

Chemical and physical characterization on site

The addition of the EB lab units is part of our dedication to working with our customers to find the best and most efficient curing systems. It is a promising technology that enables high-quality finished products, and we’re excited to offer customers the ability to expand their range of applications and give them a competitive edge in the marketplace.

Xavier Drujon, Technical Manager for Coatings at Sartomer Europe

Solution expertise and dedicated materials

Our Sartomer® materials significantly boost the benefits of EB curing by enhancing properties:

High gloss
Abrasion resistance
Deep penetration
High-speed processing

Through material design and formulation fine-tuning, our products can support you to achieve a broad range of properties.

Product finders by region

Sartomer® product finders offer advanced product search, comparison features and sampling.

Select your region:

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