Replying to Why Are Most Printed Circuit Boards (Computer Boards) Green?

interesting topic... although there's a lot of other color circuit boards, majority are green... i think circuitry boards were invented by martians hehe

that is a weird question and funny thing is I bet what ever the reason for starting and staying with green is the culprit as to people doing Hightech style movies (Matrix, Equilibrium etc.) have chosen to overcast them in green (the matrix in particular because they wanted the actual matrix scenes to be green cast to give the feeling that you were inside a computer) I have one theory and that is that maybe the reason is because the boards use copper and the green is such a sharp contrast so as to allow assemby by humans to be easier on the eyes to find the openings. What is funny is that that mask is how I intend to generate a sort of PCB etching system that is automated using very low wattage lasers to remove the material to allow the etchant to work. then once the copper is gone the same lasers will drill out the fiberglass board to make the holes.

The transparent green soldermask is still the most reliable type of LPI available. Its a two part product with hardener that is cured over the bare circuits as a final resist to protect the copper circuits from oxidation or other potential damage. It also allows the standard white epoxy legend to show up for parts placement and identification markings. Engineers sometimes choose alternate color pigments to categorize boards as prototype or test versus final revisions. Email me if you have any questions on pc board design or manufacturing and I will be happy to try and answer it, XXX@YYY.com.

BUT why should it be green? is it because it was the standard then or cheapest that time? how about white or black -sure these neutral color should be cheap.
My guess is that, green dye could surface the gold copper circuits more visibly and clearly for the electronic components to be attached and mounted soon after the PCB is ready for further manufacturing.

that is a weird question and funny thing is I bet what ever the reason for starting and staying with green is the culprit as to people doing Hightech style movies (Matrix, Equilibrium etc.) have chosen to overcast them in green (the matrix in particular because they wanted the actual matrix scenes to be green cast to give the feeling that you were inside a computer) I have one theory and that is that maybe the reason is because the boards use copper and the green is such a sharp contrast so as to allow assemby by humans to be easier on the eyes to find the openings. What is funny is that that mask is how I intend to generate a sort of PCB etching system that is automated using very low wattage lasers to remove the material to allow the etchant to work. then once the copper is gone the same lasers will drill out the fiberglass board to make the holes.

Well, the solder mask is what make the board green. Here is how it works...

A non conductive core is made out of some type of resin, usually something like polyester resin you would find at a auto parts store to repair auto body damage. This core is coted on both sides with copper (in some cases a different material is used like gold). The board is then "printed" by removing the copper to separate the different circuits (lines on the board). This is done by etching the board with a chemical after printing a protective ink on the places you don't want removed.

Now you have a printed circuit board but it is tan and copper colored. You a little more work prepares the circuit board for soldering of various electronic pieces onto the board like microchips. The board is then coated with the soldering mask which prevents stray solder from bridging between two or more circuits on the board, it also prevents the circuits from corroding or being scratched or damaged in some way. This coating is the source of your green tint! More than likely, this compound was the only available product. Keep in mind that you have to be able to see through it and it has to be resistant to the heat of the solder. It also have to be scratch resistant. So, my guess is that this was the native color of the first solder mask that was developed and remained the standard color for so long because it was the cheapest to buy either because the process is easier or because that is the most widely produced color.

Most video cards today are not green. And even my motherboard from Intel is blue. The change in color has nothing to do with anything but product promotion. I've seen circuit boards in nearly every color now. Some even sport multicolored coatings. This is the same reason that you see different colored sockets for your addon components such as different IDE and SATA plugs on boards. The traditional was always black but now they even have neon colored slots.

It is just a way to get people to buy a product based on how it looks instead of how it works.

Back to the circuit board information, after the green solder mask is applied, the silk screened printing is applied. This is all of those little numbers and letters next to each item on the board and may also show the name and model of the circuit board. Finally, the board is loaded with various electronic pieces such as microchips in an automated soldering machine.

The board might be tested or have additional work done on it then is packaged and shipped to the warehouse.

Just remember, just because the manufacturer spent extra money for the red coating instead of the green, doesn't mean that the component is better!

vujsa

Whoa, why did my topic name changed? lol ... anyways, I think vujsa explained it the clearest. I guess that's the reason because it's pretty reasonable actually. I know that boards need to be coated so that it won't break or scratch.

Thanks vujsa for that answer.

xboxrulz

I guess so, like I was looking at these electronic component I have, and actually the only ones that have been dyed were things that were computer parts. Actually, I think I've only seen motherboards in other colours because I think the manufacturers realized that system builders got sick and tired of looking at the constant green. The motherboard is also the biggest computer component inside a tower, so that's what I think.

Your thoughts?
xboxrulz

Well, the solder mask is what make the board green. Here is how it works...

A non conductive core is made out of some type of resin, usually something like polyester resin you would find at a auto parts store to repair auto body damage. This core is coted on both sides with copper (in some cases a different material is used like gold). The board is then "printed" by removing the copper to separate the different circuits (lines on the board). This is done by etching the board with a chemical after printing a protective ink on the places you don't want removed.

Now you have a printed circuit board but it is tan and copper colored. You a little more work prepares the circuit board for soldering of various electronic pieces onto the board like microchips. The board is then coated with the soldering mask which prevents stray solder from bridging between two or more circuits on the board, it also prevents the circuits from corroding or being scratched or damaged in some way. This coating is the source of your green tint! More than likely, this compound was the only available product. Keep in mind that you have to be able to see through it and it has to be resistant to the heat of the solder. It also have to be scratch resistant. So, my guess is that this was the native color of the first solder mask that was developed and remained the standard color for so long because it was the cheapest to buy either because the process is easier or because that is the most widely produced color.

Most video cards today are not green. And even my motherboard from Intel is blue. The change in color has nothing to do with anything but product promotion. I've seen circuit boards in nearly every color now. Some even sport multicolored coatings. This is the same reason that you see different colored sockets for your addon components such as different IDE and SATA plugs on boards. The traditional was always black but now they even have neon colored slots.

It is just a way to get people to buy a product based on how it looks instead of how it works.

Back to the circuit board information, after the green solder mask is applied, the silk screened printing is applied. This is all of those little numbers and letters next to each item on the board and may also show the name and model of the circuit board. Finally, the board is loaded with various electronic pieces such as microchips in an automated soldering machine.

The board might be tested or have additional work done on it then is packaged and shipped to the warehouse.

Just remember, just because the manufacturer spent extra money for the red coating instead of the green, doesn't mean that the component is better!

vujsa

I guess so, like I was looking at these electronic component I have, and actually the only ones that have been dyed were things that were computer parts. Actually, I think I've only seen motherboards in other colours because I think the manufacturers realized that system builders got sick and tired of looking at the constant green. The motherboard is also the biggest computer component inside a tower, so that's what I think.

Your thoughts?
xboxrulz

I agree that there probably isn't a real 'reason' so much as something that just became the historical norm. Probably something they used in one of the old processes was most commonly able to make the end result green, and after that they just kept doing so out of tradition rather then necessity. Obviously, as pointed out, other colors have become available and its not like the dye color of the silicon actually affects performance So yea, I doubt there is a real 'reason' but probably just something that was easier to leave it green then make it other colors back in the earlier years of computer construction.

Its a really weird question lolol!
My motherboard is red
I don't think it does anything just easy to differentiate from the circuits and things. I also think as they are inside computers and cases there isn't any need to make them look pretty.

thats my $0.02

You made me wonder too, even though I saw, red and blue circuit boards, but definitely the green ones are the most popular since the time microelectronics appeared, even though I saw that most of older schemes were light brown, maybe it just depends of the material it's made of? As I understand, all the parts aren't only silicon, they're made out of different stuff with different layers and those red and blue circuit boards, maybe they're just painted? or someone added some colour to it, to make it fancy? and cool?

I think people who knows electronics and hardware more than us could answer it