Photosensitive dry film, DuPont Riston, 6 metres
Photosensitive dry film DuPont MM540
The photosensitive film is DuPont Riston MM540. It is a industrial used high quality material.
Will be shipped in one continuous roll 318 x 6000 mm.
You will need developer - buy it here.
To make your printed circuit board follow these steps:
1) Cut photosensitive film and peel away a protective foil from one side of the film.
2) Apply resist to your clean pcb sheet. You can do it by two ways:
A) Carefully apply resist by your hands. Try to avoid air bubbles. Once you are done, use an iron heated to 105 °C, put a sheet of paper on the resist and apply the hot iron.
B) Although this is dry film, you can apply it by wet lamination. Pour your pcb sheet by water so entire surface of pcb is wet. Then apply photoresist. Carefully push water or air bubles out by using soft cloth. When all water and air bubbles are out of the board, feed hot roll laminator by the board.
3) Expose it. By using a knife peel away the top protective layer. Don't damage the photoresist - if you see you are damaging it try to peel away the protective layer from other side of the board. Put your negative artwork (black areas will be etched) on the photosensitive film, place a sheet of transparent glass or plastic on it. Expose it using UV ligh source. If your UV light source produce too much heat, keep the temperature of the board low (40°C max). Exposure time depends on your UV light source and the distance between UV light source and the board. Properly exposed photoresist will be much darker after exposure.
4) Develope the photoresist. Put the exposed board in the developer and wait for 3 minutes. You can heat the developer to 30 °C to speed up the proccess. When you see the board is developed everywhere (beware of places where spacing between traces is small), rinse the board in water.
5) Etch by ferric chloride or HCl + peroxide, than wash the board.
6) The last step is to strip the rest of photoresist away. Mix 50 g of sodium hydroxide (NaOH, can be bought at drug store) with 1 L of water. Wait till all the photoresit is stripped. Wash your board and it is done. You made professionally looking PCB.
Store the film in a completely dark place and at temperature below 20 °C. When working with the film be at a dark room.