Printing Highway Signs

Sounds like an ASK.com kinda question to me.

ehow.com maybe too

Typically, they're silk screened. While the signs look like photos, if you get real close you can see that they're made up of little dots of color - each screened one-at-a-time.

Not only have I silk screened in the past, but I had a friend that had a severe crush on a lady on a billboard... Late one night, we climbed the sign, and removed here. She nearly took up all the walls in my friend's room, but it made him one happy boy!

i worked one summer for penndot (that's what the PA mva used to be called) in their sign department around 1977, so i don't know if the process is the same or not today....

there were 2 types of signs, silk screened and labeled.

we had the cabability and equipment to make the artwork, create the mask and shoot the screen....

the screen was coated with a photo sensitive emulsion. the parts that saw light became hardened and the parts that didn't stayed soft.. a solovent was used to wash away the soft parts and you were ready to start printing.

the raw signs were delivered in a big stack on a pallet, a person would feed them one at a time to the printer guy, he would screen the sign, and put it on a conveyor belt that would take it thru the drying oven,,,,,,,,,at the end another guy would stack them back on a pallet

if they were finished they'd be packaged for shipment, if they needed more colors, they went back thru the line until they were finished, probably days or weeks later

the label type were made with adhesive tape, these were mostly the big green interstate type of sign, some were so big that they were made in pieces and then fitted together at the site........

the back ground color came on big rolls, 4-5 feet wide.........the bare sign was feed onto the conveyor and the tape was unspooled and adhered to the sign, it was trimmed and then went thru some rollers to flatten, not getting bubbles was the challange........

the letters were pucnhed out of other adhesive backed tape, and then hand applied to the sign...