RAHN launches printed electronics initiative

RAHN group, a privately held Zurich based company is a global leader for energy curable (UV/EB) solutions for graphic arts applications.

 

To support new developments in the rapidly emerging field of printed electronics, RAHN has developed a product flash to summarize the products and support that they can offer to companies considering energy curing as an option for fabricating printed electronics products.

 

Suggested benefits are

 

• Adhesion to difficult substrates

• Low shrinkage.

• Anti-reflective

• Heat resistance

• Moisture and oxygen barriers

• High flexibility

• Hydrophobic properties

• Thin and thick film curing

 

Further information and a copy of the ENERGY CURABLE TECHNOLOGIES AND PRINTED ELECTRONICS Product Flash can be obtained by clicking direct link http://www.rahn-group.com/ProductFlashElectronics_EN 

Energy curing is the broad term used to describe the technology

used to "cure" or rapidly dry specially formulated inks, coatings and adhesives.

 

The technology is widely deployed in conventional graphic arts printing bringing the following motivations versus other technologies like solvent

based and water based solutions.

 

1. Increase productivity

2. Improved physical properties/product performance

3. Enabling technology/new capabilities for user

4. Cost effective/lower price

5. Environmental compliance/green technology-100% solids

6. Suitability for heat sensitive substrates

 

Energy curing is normally broken down to two curing techniques:

 

■ UV curing, this means formulations that are cured by exposure to light in the 200-400nm sector of the electromagnetic spectrum.

■ EB curing, this means formulations that are cured by exposure to high energy electrons.

 

Components of energy curable formulations are:

 

Oligomers: The overall properties of any coating, ink,adhesive or binder crosslinked by radiant energy are determined primarily by the oligomers used in the formulation.

 

Oligomers are moderately low molecular weight polymers, most of which are based on the acrylation of different structures. The acrylation imparts the unsaturation or the "C=C" group to the ends of the oligomer.

 

Monomers: Monomers are primarily used as diluents to lower the viscosity of the uncured material to facilitate application. They can be monofunctional, containing only one reactive group or unsaturation site, or multifunctional. This unsaturation allows them to react and become incorporated into the cured or finished material, rather than volatilizing into the atmosphere as is common with conventional coatings.

 

Multifunctional monomers, because they contain two or more reactive sites, form links between oligomer molecules and other monomers in the

formulation.

 

Photoinitiators: This ingredient absorbs light and is responsible for the production of free radicals. Free radicals are high energy species that

induce crosslinking between the unsaturation sites of monomers, oligomers and polymers.

 

Photoinitiators are not needed for electron beam cured systems because the electrons are able to initiate crosslinking.

 

Additives: The most common are stabilizers, which prevent gelation in storage and premature curing due to low levels of light exposure. Color

pigments, dyes, defoamers, adhesion promoters, flatting agents, wetting agents and slip aids are examples of other additives.

 

There will be many emerging applications in printed electronics that might benefit from utilizing energy curing as the technology to cure or

dry the printed functional pattern. Energy curing could also be employed to protect such printed patterns or for other parts of the fabrication

process.