Anyone have L*a*b* color numbers for MUTCD traffic colors?

[bteifeld]

The standard colors for traffic signs in the MUTCD specification are given in a two
dimensional xY number form. I am sure there is a way to convert this into L*a*b*(Lab),
but I don't know it. Info would be gratefully appreciated.

 

[Bobby H]

The Federal Highway Administration has Pantone spot color standards for publishing illustrations of traffic signs in paper-based documents:
https://mutcd.fhwa.dot.gov/kno-colorspec.htm
You can develop L*a*b approximations from those Pantone specs.

For actual traffic signs that will be installed in the field the signs must use approved materials in fabrication, such as the various kinds of Type III retro-reflective sheeting on sign backgrounds and reflective vinyl for lettering and other elements. They cannot be churned out of a large format printer.

 

[bteifeld]

Thank you for that information. I actually have seen the webpage
you were kind enough to provide. Because that page is very clear
that the pantone approximations are not meant for printing, this is
why I asked what I did. The actual MUTCD specifications do mention two
dimensional xY color specifications for the standard traffic sign colors-
converting that to L*a*b* was what I was hoping to find out if
someone could explain that to me, or just provide the actual
L*a*b* numbers.

Also, Mutoh and HP in cooperation with Avery-Dennison and
3M respectively have integrated and approved large format print
solutions for direct large format printing of vinyl traffic signage. I'm
a little confused by what you are saying as a result.

 

[Joe House]

Also, Mutoh and HP in cooperation with Avery-Dennison and
3M respectively have integrated and approved large format print
solutions for direct large format printing of vinyl traffic signage. I'm
a little confused by what you are saying as a result.

These all inclusive packages HP/3M, Mutoh/Avery and others are utilizing an integral RIP with custom CMYK formulations of ink that are specific to the ink/media/rip settings combination. A L*a*b* value may work during daylight, but might not give the correct color when viewed at night with the retroreflective light properties. They have made sure that these color formulas work within their narrow ecosystem and any attempt to pull out info to use in another system will not be an approved "system" any longer.
Now, can you get your RIP to print that same red for the stop sign? - most likely. But when someone blows that stop sign and kills someone saying they didn't see it, and the investigation leads to a non-compliant sign, who's gonna be the target for a lawsuit then? Anyone who had anything to do with that sign - the guy who put it up, the guy that made it, the guy who said "My RIP can produce signs that comply with MUTCD", etc.
If you want to get in the game, you're really going to need to do the legwork and get the certification for your system. On the other hand, if you just want to print graphics that look like street/highway signage for commercial, non traffic use, the pantone colors should do the trick.

Good Luck

 

[bteifeld]

Thank you for further explaining Joe.

 

[Bobby H]

Also, Mutoh and HP in cooperation with Avery-Dennison and 3M respectively have integrated and approved large format print solutions for direct large format printing of vinyl traffic signage. I'm a little confused by what you are saying as a result.

What I mean is that you can't simply print flat colors onto any kind of standard vinyl and expect that to pass for highway sign standards.

The only kinds of printing that can be done is various degrees of transparent/translucent printing onto clear vinyl as an overlay on white Type III high intensity retroreflective sheeting. For transparent overlay work using the approved colored transparent vinyls gives a better looking result and yields a sign that lasts longer in the field than something printed. Most highway sign departments just cover the backgrounds with the green type III sheeting and then apply the other vinyl graphics on top. The lettering (or "legends") is typically engineer's grade white vinyl (which fails faster and has to be replaced frequently -we're a long ways from the "button copy" days of old). The route shields are often routed aluminum parts decorated with vinyl (or screen printed).

There is a lot of stringent rules regarding highway signs, some of which I see broken all the time by certain highway sign departments (cough -ODOT- cough). It's pretty funny to see a "big green sign" that was jobbed out to a sign company that didn't follow the rules. Wrong materials, wrong fonts, etc.

 

[bteifeld]

M64s-Nik

What I mean is that you can't simply print flat colors onto any kind of standard vinyl and expect that to pass for highway sign standards.

The only kinds of printing that can be done is various degrees of transparent/translucent printing onto clear vinyl as an overlay on white Type III high intensity retroreflective sheeting. For transparent overlay work using the approved colored transparent vinyls gives a better looking result and yields a sign that lasts longer in the field than something printed. Most highway sign departments just cover the backgrounds with the green type III sheeting and then apply the other vinyl graphics on top. The lettering (or "legends") is typically engineer's grade white vinyl (which fails faster and has to be replaced frequently -we're a long ways from the "button copy" days of old). The route shields are often routed aluminum parts decorated with vinyl (or screen printed).

There is a lot of stringent rules regarding highway signs, some of which I see broken all the time by certain highway sign departments (cough -ODOT- cough). It's pretty funny to see a "big green sign" that was jobbed out to a sign company that didn't follow the rules. Wrong materials, wrong fonts, etc.

Thank you for explaining- I'm curious- how do(es) the failure(s) manifest? Is it fading of the inks despite outdoor laminates, or insufficient ink density, or perhaps delamination, etc.?

 

[rjssigns]

The MUTCD compliant Mutoh printer would be a TrafficJet.

The dealer where I bought my Mutoh manufactures the parts for them.

 

[Solventinkjet]

These all inclusive packages HP/3M, Mutoh/Avery and others are utilizing an integral RIP with custom CMYK formulations of ink that are specific to the ink/media/rip settings combination.

They also have custom spot colors added as well such as brown and green. At least on the Mutoh version anyway.

 

[Bobby H]

Thank you for explaining- I'm curious- how do(es) the failure(s) manifest? Is it fading of the inks despite outdoor laminates, or insufficient ink density, or perhaps delamination, etc.?

Laminates do only so much to protect printed inks from UV radiation. Plus the effects of weather take their toll over time. The stuff is not as durable as the stock colored high intensity retro-reflective vinyls. But the digital printed approach can be less expensive. Ultimately it's a trade-off between a better quality, longer lasting product versus one that is faster/cheaper to produce.