The term "Direct Etch" simply refers to the technique of applying a circuit image directly on top of a blank copper-clad board then etching away all exposed copper around the image. Everything is done in bright daylight as nothing is photographically sensitive! The printed "toner" image is primariy made up of pulverized syrene plastic which is a natural etch "resist".
For those reading this that are, say under 40, may not be aware of the "sticky tapes" we had to use for making very crude PCB's up through the 70's. Along with the tapes we had pre-imaged "dry transfers" that were rub-down patterns of IC's and transistors put directly on top of the copper (or on acetate sheet if you were going to use the nasty photograhic method). The pattern on the board was a 1-shot use! The board was then submerged in an etchant to remove all of the exposed copper surface. When done, we'd pull off all of the images, drill the board and we were done. Repeatability? Zero! It was purely for basic hobbyists.
We had no real way to do anything complex on copper so most everything was "wire wrapped". Those were very scary days!
Then along came the laser printer in the mid '80's. We had a fantastic imaging system but had no reliable way to get the image out of the printer and onto the copper board. The toner "ink" being 55% pulverized plastic was a shoe-in as an etch resist but alas, no fool-proof way to transfer the image. Some tried, but there just wasn't a simple, perfect, repeatable and viable method. This necessity became the mother of invention to bridge the gap.
In 1992 we introduced our product called "Toner Transfer System". It wasn't much of a system... just a transfer paper that had a remarkable property in that it would release any image printed on it when wet. We were the 3rd company to introduce another "technique" on the market primed for something better. One of prior two was TEK2000 but failed over the years, the other is called "Press 'n Peel" by Tecniks who is still with us today. They are in effect, one of our direct competitors, however, we go far beyond what Tecniks product offers in the way of performance, density, ease, follow-on capabiity and cost which we hope you'll learn about in the coming pages!