Publication date: 29 April 2010
Sono-Tek is the world leader in the development and application of ultrasonic coating systems for electronics and advanced energy applications. Compared to conventional pressure spraying methods, the company’s ultrasonic nozzles do not clog, and reduce liquid usage, waste, and environmental impact while achieving much more precise, uniform, thin film coatings. Sono-Tek is continually developing new applications for its unique technology, replacing wasteful practices in a world that is growing ever more environmentally sensitive.
A. First and foremost is the electronics industry. This is where our company made its mark by introducing the ultrasonic spray fluxer to PCB manufacturers in the early 1990s, and we have been the leading spray fluxer manufacturer ever since. More recently, we have added new products to serve the growing advanced energy market, with our ExactaCoat and FlexiCoaters providing a superior way to apply expensive thin films to fuel cells and solar cells with minimal waste and great precision. Sono-Tek also has applied its coating systems to other industries, including manufacturers of implantable medical devices and major industrial customers in the glass, textile, and food industries.
A. It all starts with the ultrasonic approach to atomizing a liquid to create a coating, which results in a low energy spray that provides great uniformity and does not wastefully bounce back into the environment. We can then separately shape and control the geometry and impact of the liquid particles to achieve a variety of coating objectives. The ultrasonic nozzle itself has a large bore with no restriction, so clogging is a thing of the past — and maintenance is greatly reduced, even with sticky rosin fluxes.
A. The principal advantage is in reduced maintenance and downtime, resulting from the non-clogging nature of the nozzle itself. Another advantage includes greater precision of the flux coating, which in-turn, results in higher product reliability and lower reject rates. The ability to handle rosin fluxes has become increasingly important as manufacturers shift to lead-free solder with benefits from the use of rosin fluxes.
A. We have developed a series of robotic machines that contain XYZ axes, allowing our nozzle systems to move over the conveyed or stationary work piece in any programmed manner required. These machines come in a bench-top configuration suitable for development work on fuel cells and solar cells known as the ExactaCoat, as well as in a freestanding configuration with a conveyor capability suitable for production work, known as the FlexiCoat. There are different versions of both of these primary machines, some for solar cells and others for fuel cells, with different capabilities and options such as low oxygen, inert atmosphere, very high-temperature substrate capability, etc.
A. This is a very exciting field, and our business of providing precision coaters for implantable medical devices is growing on a global basis. We began with cardiac stent coaters nearly 10 years ago, and have since branched out to provide specialized equipment for coating peripheral vascular stents, balloon and catheter coaters, bone replacement implant coaters, hernia mesh coaters, and more. This will continue to be a growth segment for us as more coated implantables are developed to meet emerging medical needs.
A. Nanotechnology applications benefit from small and uniform droplets, which lead to the uniform particles or coatings that are required in this field. Traditional spray dryers with pressure nozzles produce too wide of a distribution of particles compared to an ultrasonic spray dryer, so there is a significant process yield benefit with our nozzle systems.
Our equipment also is used often to apply nano-layer coatings. The liquids used for these coatings typically contain a suspension of millions of nano-particles. These tiny nanoparticles have a natural tendency to agglomerate together, creating a larger clump of particles and thereby reducing the benefit of them being nano in size. The high-frequency vibration of our ultrasonic nozzles will separate the clumps of particles back into individual nano-particles, allowing them to provide their intended benefit of being nano in size. One example is for a self-cleaning glass coating application, where the ultrasonic spray allows the nano-materials to de-agglomerate and become more readily assembled on the surface of the glass to produce the desired properties — something that is not possible with pressure nozzles.
A. The first step is the reciprocation itself, which positions the nozzle under the holes in the circuit board as they pass over the moving nozzle. The second step is the Impact Nozzle itself, which combines precise non-clogging ultrasonic atomization with the ability to direct the liquid flux droplets at high velocity, literally driving the flux up through the through-holes on the PCB, providing the best topside fill in the market — but avoiding wasteful overspray and environmental contamination.
A. The SonoFlux EZ is available in either a standalone version for placement in front of a wave solder machine or a retrofit version for incorporation inside of a wave solder machine. The ability of the ultrasonic nozzles to handle rosin fluxes without clogging and minimal maintenance is what sets this equipment apart from other approaches.
A. We expect to continue to selectively identify applications and industries that would benefit from our technology, and to create solution platforms to meet existing needs. A good example is our new Hypersonic platform, which is just now being applied in a joint venture with Rensselaer Polytechnic Institute in New York State for high-production fuel cell coating applications. The Hypersonic is a very fast and wide reciprocating platform, and the joint venture program is designed to show its suitability for fast moving fuel cell production lines.
