[nanoPost] Nanoparticle conductive inks

Company USA

The company manufactures nanomaterial-based products for use in electronics applications.  These products include conductive inks and pastes for inkjet and conventional printing of electronics. The company's technologies can achieve high conductivity and help improve overall performance, both of the circuits and the systems in which they are employed. 

The company’s materials are based upon a proprietary solid phase manufacturing process that creates nanometals and nanometal alloys. This advanced manufacturing process produces materials with attributes well-suited for electronics manufacturing:  

- Small particle size (D100 < 80 nm)
- Narrow size distribution
- Crystalline structure
- Various metal and metal alloy capabilities

The company focuses on those metals and metal alloys that are the most valuable to electronics applications. The company currently produces nanometallic silver and silver/copper alloys and can also produce a variety of other materials, including platinum and palladium.

To be used in most printed electronics applications, nanomaterials must be dispersed in a matrix. This dispersion is as important as the nanomaterials themselves because it affects conductivity, adhesion of the circuit to substrate, and other important properties of the final electronic component. The company's formulations complement the nanomaterials to deliver important attributes including:

- Ability to disperse in a wide range of solvent systems, including those commonly used in the graphics printing and electronics industries and are compatible with a wide variety of substrates commonly used (plastics, paper, glass, ...)
- Organic coatings that maximize dispersion while minimizing effects on performance
- Increased stability
- High metal loading (<60% by weight) with low viscosities (inkjet printable)
- Additives that deliver other desired properties are used to enhance specific attributes unique to the material delivery method, whether it be inkjet printing, coating, or a variety of other different printing methods.

The company engineers various formulations of its materials to specifically fit the deposition systems and applications of customers and partners. Interaction between the formulation and deposition system affects the performance of the final component. Specific deposition methods may be better suited for a given component.

Coating

A simple bar-coating method is used to apply the company’s proprietary conductive coatings. This can be done by batch or continuous methods, making possible the manufacture of conductive films on a variety of substrates, from discrete glass pieces to roll-to-roll coating on flexible, low temperature substrates.

Inkjet Printing

Advances in nanotechnology have enabled the inkjet printing of metals. The metal particles must be small enough to pass through the inkjet nozzles without clogging them. Generally, particles must be smaller than 100 nanometers. The nanometallic particles must be dispersed in a liquid vehicle for inkjet printing.

Inkjet printing electronics offers the potential for three-dimensional printing, thinner lines, less material usage, and the customization, flexibility, and low set-up costs of digital processes.

Conventional Printing

Printing processes such as gravure, flexography, lithography, and screen printing can enable high-speed, roll-to-roll printing of electronics. In some instances with these printing processes, nanomaterials offer value through finer line resolutions and lower-temperature sintering requirements which enable low cost substrates.

The company inkjet series currently consist of conductive nanometallic silver/copper intermediate inks designed to serve as a platform upon which the company works with customers to build a final ink, engineered for the customer’s electronics application.

The inkjet series begins with optimally-sized silver/copper nanometallic particles. These particles are coated with organic materials which prevent agglomeration when the particles are dispersed in a liquid vehicle. The company uses solvents familiar to and proven in the graphics industry to create the dispersions. Additional solvents, binders, surfactants, and additives modify the properties of the ink to suit the printing system and customer application. 

Customers can print inkjet inks through commercial or desktop printing systems. The company's inkjet inks support atomization, piezo and thermal inkjet technologies and are available in solvent-based and aqueous-based formulations with metal loads up to 60% by weight. The inkjet inks include basic formulations designed for printability and conductivity and advanced formulations which include additional properties like adhesion to specific substrates or modified drying time.

In addition to digitally manufacturing circuits, some applications (e.g., RFID) utilize other printing processes common to the graphic arts industry.  In order to be used in these different processes (gravure, flexographic, lithographic, screen), the inks must often exhibit very different characteristics.  The company's series of conductive ink formulations can enable use of a wide variety of different printing methods.  These formulations exhibit the company's expertise in adapting formulations based upon important parameters, including the ability to change viscosities, control wetting characteristics on various substrates, and adapt to different curing conditions.  Because these applications are often unique, the company has become expert in efficiently customizing formulations geared to the manufacturing and application demands of the customer.

The company offers transparent conductive coatings (TCC) for electronics applications. A unique self-assembly capability allows coated films to replace current flat panel display solutions such as copper mesh for EMI shielding while meeting or exceeding performance requirements. The process is simpler, faster and more efficient because it replaces complex manufacturing processes with a simple coating procedure. Other TCC application areas include smart windows, electroluminescence, and solar cells.