These days Toner Transfer Method for PCB design has become popular. While conventionally, heat usually using cloth iron or laminator is used to impress the toner onto the copper clad of the PCB board, there is also an alternative to this step of toner transfer which is using without heat. Without heat? Yes that's right.

The technique in this is to utilize the fact that for the toner transfer on the copper clad, the toner must be somehow melt and stick to the copper plane. While in heat transfer technique, the toner and copper board are both heated the toner gets stick to the copper board. In heat-less transfer technique, acetone and alcohol mixture is used to melt the toner and stick onto the copper.

The science behind this is that the acetone from the acetone and alcohol mixture will dissolve the toner while the alcohol will not. That is alcohol is inert to the toner. So the role of alcohol in the mixture of acetone and alcohol is just to dilute the acetone such that the mixture just softens the toner and stick to the copper board. 100% acetone will dissolve the toner completely, smearing out the toner from the printed glossy paper which is usually used. However adding appropriate amount of alcohol to the acetone and using the mixer to stick the toner printed circuit on to the copper can make the transfer work.

The question is how much alcohol to add to the acetone. As far as experiments conducted by DIY people are reported, the mixer largely depends on the following factors:

1. laser printer being used, like HP, Canon etc
2. the toner of the printer, like quality of the toner of different manufacturer
3. the paper used- like glossy paper or ordinary paper etc

The proportion of alcohol and acetone by most experimenters is found to be alcohol:acetone=8:3. That is 8 part alcohol and 3 part acetone.

Now, the process of using the mixture during the PCB design is simple. The crucial step is how to apply the mixture. The steps are as follows:

1. Print your circuit onto a glossy paper
2. Smear your mixture onto the copper board
3. Gently position and place your glossy paper onto the mixture such that the toner touches the mixture. Do not apply pressure, just place it onto the mixture and wait for 5 to 10 seconds for letting the toner dissolve.
4. Now press uniformly and perpendicularly onto the glossy paper
5. Wait for more than 2 minutes to make the toner stick to the copper
6. Dip the board into water for more than 2 mins
7. Gently peel the paper from the board and you should see the transfer of toner from paper to copper board

Now you are ready to for the etching step.

Here is one result of PCB board of this reported technique.

PCB design using Toner but without Heat


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