Back in the early 70's sticky tapes and rub down dry-transfer patterns of IC's and transistors were put directly on top of the copper and then etched in a tray with some ferric chloride. 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 came the laser printer in the late '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.
First on the market was a clear film with a silicon coating called TEK-2000. Somtimes it worked but most of the time it didn't make a perfect transfer. Most people swore 'at' it instead of 'by' it. Reliability just wasn't there and over the course of time this one faded into obscurity.
Next came "Press 'n Peel" from www.techniks.com. It has a blue release coating over a heavy acetate sheet that reliably takes the toner image from any laser printer. We were next with a different approach... using a zero-friction release transfer medium normally associated with "water-slide" decals.
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art of the problem to make both Press 'n Peel and our own Toner Transfer System to work reliably, rested with the operator using a household clothes iron, to apply the correct pressure and heat. Both parameters had to correct or else the image would either fail to transfer or on the reverse side of the coin, the image would transfer but be distored, which as we all know is like being a little bit pregnant. It has to be a perfect transfer to be usable. The only way to know was trial 'n error. There had to be a better answer to this problem!
We solved this illusive problem by using an unmodified, "off the shelf" pouch laminator made by GBC. We tested a dozen different makes and only the GBC proved to work for our purposes. At $69.95, our "Personal" model we call a "Toner Image Applicator" (or TIA) finally puts to rest the problem of how to apply the correct pressure and heat. In one quick pass you're image is properly fused to the copper surface. The transport mechanism moves your board through at 6sec/inch.
Our competitor's solution is to use a 9"x12" T-Shirt Press costing $339 - nearly 5 times the price of the our laminator. We're often asked if our laminator will work with their Press 'n Peel product. Unfortunately it will not. The carrier used in their product is too heavy to allow enough heat to penetrate for a proper fusing of the toner image.
Back in the early days when an iron was used as the main heat & pressure device, it always seemed somewhat unpredictable to get a perfect transfer every time. Many users had to try multiple times to get one just right. This definitely kept us in the "hobby" world as it couldn't be taken seriously. As the years went addressing this problem, we began to understand that there is a direct relationship between total pressure and total heat. They actually work inversely to each other. Also, there are two temperatures; fusing temp and melting temp. The former is the point at which the toner will stick to what ever it's touching without distorting. Melting temp is when the toner starts to liquify, distorting the image. Akin to stepping on a peanut butter & jelly sandwich. Well, up to this point in time, everyone thought more pressure and more heat was the answer. We have learned that was not true. It comes down to this; the greater the pressure applied to the paper, the lower the required temperature. Giving in effect a spread away from the melting temperature. The problem was, an iron can't delivery enough pressure to be able to reduce the temperature very far away from the melting point of toner. Even standing on an iron only gives a dozen PSI at best as compared to hundreds of PSI from the laminator as applicator. There is a lot more to this understanding but we don't want to bore you with the details... surfice to say, we now have a low cost solution to the problem of applying the correct heat and pressure. Our process is now being accepted in all advanced electronic fields. Even though our process is limited to doing single and double-sided boards, that does account for amost 85% of all boards being made today.
As the years rolled on, we continued to improve on the process technique. Our transfer paper medium had increased dimensionally stability, the amount of copper on the boards idealy set at 1/2oz vs. 1oz and we had a way to seal the toner to prevent pitting. The entire process fully matured in 2001.
With our current process technique using an ordinary laser printer (barely over $100) you can image at 1,200dpi for exceptional circuit resolution allowing circuit trace pitch down to an amazing .005", fully capable of working with all SMT components with ease, and do it all in just a few minutes.
Our process now for the first time, directly competes with "overnight" board houses for 1x and 2x board fabrication. The most expensive "over night" service is still a long time to have to wait when compared to our 8 minute process and then there's the high cost of the overnight service! WOW! There just simply is no need to do this anymore so stop wasting money. For what it costs to have ONE rush board made, you can own our entire system for only $145!
Our technique couldn't be simpler. Print your circuit pattern, transfer high-density PCB layouts to our inexpensive fiberglass 1/2oz copper laminate, add a sealing foil over the toner to prevent any pitting of the copper, etch the board in under a minute (without an etching tank we might add) then wipe the image off the board with acetone and you're ready to rock 'n roll. It simply can't be beat... and we back that up with a full month, money-back guarantee! "If you don't love it, we want it back!" (even if the kit supplies are used). Just send us back the remaining elements of the kit and lamiantor along with your results you didn't like and we're refund your total product purchase price.