Issue link: https://iconnect007.uberflip.com/i/1288481
SEPTEMBER 2020 I PCB007 MAGAZINE 29 mil solder dam or line width. That level of im- provement is huge. We'll be releasing models with those print heads in the near future. We're in the third generation of our solder mask inks and still working hard to im- prove them. We also have a new eight-head printer for maximum through- put. It can print solder mask on a standard panel in under a minute. Lastly, we have released a new sophisticated in-line au- toloader and unloader, which works with all our models. Matties: Are those only for jetting, or do you provide inks for other applications? Harding: That's a good question. They're for jetting only. We only produce jettable solder mask inks for flex and for rigid, and those are available in green, red, black, blue, and white for LED applications. With white, you can use it as a legend; it can be very versatile that way. Johnson: You were talking about scalloping as being a challenge for finer features. Is that primarily a mechanical issue or a solder mask ink issue? Is that something you ap- proach with print head engineering, or by formulating your solder mask to behave dif- ferently? Harding: It's a combination of those two plus proper UV application on the ink. If the UV is too strong, you will pin in the ink too soon, and then you get stronger scalloping. Inkjet- table inks are much thinner than traditional masks, so the condition of the surface is im- portant. Overall, we've found ways to combat those issues with different print strategies or by improving the surface itself. When a droplet lands, there's no way to cure it and not produce a slightly rounded edge. It's not an issue of functionality. The board will function exactly the same, but it's an issue of customer approval. A customer might say "What's with this?" or "What's wrong with the solder mask?" if It's not perfectly straight, but keep in mind nobody says that about inkjetted legend anymore and we expect that look to be more accepted and in time we hope to elimi- nate the scalloping altogether. Johnson: It's much clearer now. Great explana- tion; I appreciate that. Matties: This has been very good. I look for- ward to our next discussion because we really want to drive this conversation to the OEMs. Thank you for all your insights. I'm glad to hear you're enjoying this industry. I've been in it for over 35 years now, and there's a lot of good people in this industry. Harding: I totally agree. Matties: Thank you very much. Harding: Thank you for your time. PCB007