In general, when we talk about inkjet, we are discussing ways of jetting small drops of low-viscosity inks, usually for graphics but increasingly also for industrial print applications. But what about those industrial uses where large drops and/ or high viscosity fluids would be more useful?
That question led Archipelago, a small start-up based in Cambridge, UK, to develop its Powerdrop drum, which takes a very different approach to traditional inkjet.
Guy Newcombe, managing director of Archipelago, explains, “We started Archipelago 14 years ago with the vision of creating new technologies. We had a lot of contacts in the industry, a bit of cash, and a reasonable level of confidence.”
The company is owned by its founders Newcombe and Dan Mace, the head of inkjet technology, together with David Carlton and Victor Habesman, both of The Technology Partnership (TTP), which offers product and technology consultancy services. Between them, these four own about 85%, with the other 15% split between other employees or ex-employees.
Newcombe started his career with a job at Domino, before leaving to do a PhD, and then working for TTP. He says: “There were a lot of inkjet companies starting at that time – Xaar, Inca, and so on. TTP asked people what they wanted and from that they created six separate businesses. So we learned how to go out and talk to people and see what they want and then invent things.”
Building on the experience gained at TTP, Archipelago started by asking a wide range of people what they wanted. Newcombe says: “We analyzed what they told us and saw two patterns: jetting adhesives and replacing spraying paint.”
That led to the obvious question – why can’t you put glue through a piezoelectric head? Newcombe explains: “There are a number of reasons. The adhesive is viscous and you can’t put viscous things through small nozzles. And it’s viscous-elastic so you could push it through the nozzle but it would snap back. So you need a bigger nozzle, more energy to push in one direction, and a very short flight path.”
Powerdrop Concept
From here Archipelago developed the Powerdrop, which is essentially a large drum full of holes that function as nozzles that are able to jet high-viscosity fluids.
Newcombe says, “The first Powerdrop was a syringe and we filled it with rocket fuel. People liked the jetting but not the rocket fuel. So we replaced that with compressed gas.”
He continues, “We knew that if we put this in a drum we could make it continuous. So we put lots of nozzles in a drum and we pushed it out from the inside. We have a cylinder and we drill nozzles in the cylinder. We rotate the drum and we have an air knife that blows it out and we can run this drum quite fast at 4mps linear.”
The fluid itself sits in a Powerdrop filler, which is located outside the drum. As the drum rotates, the fluid is pushed from the filler into the nozzles. As the drum continues to rotate the blower inside the drum forces the fluid drops out of the nozzles with enough force to overcome any turbulence and land on the substrate without any waste or overspray.
Newcombe adds: “It’s much faster than piezoelectric and we can have a much more viscous liquid, up to 2000 mpas. We can run from water viscosity up to 2000 with the same geometry. We jet hot melt adhesives, UV paints, food flavorings, and agricultural chemicals, with high or low coating weight and high or low viscosity. We can jet low and high-viscosity fluids. And we can jet hot melt glue up to 160°C, as well as UV paint and PVA glue, which is interesting because there’s a lot of interest in coating paper packaging to make them waterproof to replace plastic packaging. We can jet things with 100-micron particles and metallic paint.”
Although the basic concept can handle all these different fluids and applications, it is necessary to change the pattern on the drum for each product.
Print engine
Archipelago has taken this concept and used it to create a Powerdrop print engine, which includes all the features necessary for jetting the fluid but not the substrate handling as the engine is designed to be retrofitted to an existing production line.
Newcombe explains, “Our machine talks to the customer’s machine. It’s non-contact. As long as the customer gives us the space to put it in. We try to keep the complexity relatively low. So things need to talk to each other. But we need a millimeter rather than a micron for alignment.”
He says, “Things are just beginning as we move from startup to scaling up. We are building simple machines for people and they will get them working and then buy another new machine so the ramp up will be fairly steady but slow. We hope to be making 700 machines a year. They are not particularly complicated.”
Newcombe is quite insistent that the entire machine is made in the UK. He says, “One of the great things that is coming in is 3D printing and the UK is a big centre for 3D printing. So we are working with four different UK-based 3D print companies and getting parts made by them. And I think there is a real chance that the entire machine is going to be 3D-printed, currently a large part of it is. And it’s all being done in the UK. There is a critical mass here.”
For now, the drum is 3D printed but the nozzles are then drilled. But Newcombe says that Archipelago is looking at having the nozzles incorporated at the 3D printing stage. He adds: “The drums will be made out of stainless, aluminum or plastic depending on the application.”
Newcombe says that the machines should be easy to maintain, noting: “We are trying to minimize the service charge. A lot of people say that’s a very valuable revenue stream but things take off when they are easy and cheap and when they are difficult and expensive they don’t take off.”
He adds: “We are very strong on measuring things. We measure how the machine is operating. Everything we can measure, we do measure. And we are constantly monitoring the machine and we do it remotely when we get it out to customers. So we can detect faults before they happen. We are planning for our customers to do all the physical maintenance for the machine so we won’t have to physically go there. We can monitor the machine and advise the customers.”
He adds, “Service charge annoys people a lot. It’s a barrier to entry. And it’s an opportunity for competitors. Things take off because they are easy to use so why make it complicated? The opportunity is huge.”
He says: “We are selling a reliable machine and that customers can maintain. We sell them spares. I don’t think we need to overcharge for that service if it’s just a matter of keeping a machine purring away. We are looking at once-a-year maintenance.”
Potential markets
Archipelago has identified a number of potential applications for which its Powerdrop technology would be suitable. It is relatively trivial to adapt the print engine for different markets and Newcombe is confident that Archipelago will be able to sell a large number of quite similar machines.
The initial target is for packaging, applying functional coatings to paper-based packaging to replace plastic from the supply chain. That functionality could be to add waterproofing or grease proofing or other food-grade barrier coatings, which would not only save costs but have a huge environmental benefit. More importantly, because the Powerdrop can be relatively close to the substrate, it’s jetted with more control and much lower velocity than a spray would use so it can be used to lay down multiple coatings, one on top of the other, including wet on wet. This in turn means that multiple coatings can cure together for a better bond.
Newcombe says that there is a lot of interest in this type of non-contact low-waste coating, which he estimates to equate to around 1200 machines. He adds, “We think the opportunity is about 5000 machines for packaging. Smithers estimates that 20% of plastic packaging will convert to paper. That’s about $60 billion of packaging that will go to paper. That could include yogurt pots, and face cream jars. The cost will run from a few pence to 20p. We will end up having to coat something like 600 billion to 1000 billion items per year. So it’s similar in terms of scale to ceramic printing. That’s the scale of the opportunity.”
He explains: “If you use a spray then a lot of the spray goes off in the nozzle and gets sprayed over the machine. We can transfer up to 97% as against 50% with a spray. That’s cost and inconvenience.”
Newcombe continues, “There are brands asking people to produce this packaging. There are various companies that can make paper bottles and so on. He adds: “It will take time, at least two years to convince everyone that we can replace plastic with paper and that it can be recycled. There’s no doubt that we will need to modify what we are doing. It will take time and when we get there then it will be huge. And typically things take a bit longer than you would like.”
Other uses include industrial coatings, which are often applied by roller, limiting the range of materials, or spray, which leads to some issues with overspray.
The same approach can also be applied to agricultural chemicals, where the Powerdrop could allow for more precise application. That in turn would save costs by reducing waste from overspray as well as the risk of contaminating other nearby areas.
Not surprisingly, Newcombe believes that Archipelago has a huge opportunity with Powerdrop. He explains, “There are 6000 machines in packaging. But it’s a million in agriculture. So we wanted to cut our teeth in packaging where we are working in a factory in a relatively controlled environment and from there leap to agriculture. We just have to get the machine out there, get them working and keep them working, and then jump to the next market.”
You can find further information from archipelagotechnology.com
