Officially it's known as "Grungetastic Over-Printing"

"Mis-registered"

I assume you're joking, Simon, but, so as not to confuse Manel, I think it should be pointed out that the grungetastic part is due to years of wear and tear and was not part of the original design.

Looks perfectly registered to me. :-)

@ Manel: Are you looking for the English technical term from offset printing technology? If so, This happens when your registration is off. It's considered a mistake. The picture you posted would be an example of someone using this as a style, exaggerating it on purpose. On a related note, you might want to look at screen angles.

@Mark:

No, if it were registered it would look like this:

Ok Thanks! Is the tecnich Over-Printing that i was searching, I found that Peter Seitz did something seemed in the 50's. Thanks!

Yes, "overprinting" or also "Surprinting" is the correct term as opposed to "knockout color A and come back color B"

ChrisL

damn, i am so young. i thought this was called "photoshopping".

>How is called this effect?

ClearType for print.

Cheers!

Back in the day when production art was actually a job and strippers worked for offset printers instead of pimps. :-)
You could tell a stripper to "Step and burn" the Cyan 3 picas as red then step and burn 3 picas as yellow and get the effect Muriel used above.

ChrisL

You did have to worry about drying to avoid "picking" though. Otherwise, you could screen the overlap at CMY screen angles to avoid too much buildup.

ChrisL

I just scanned my copy of the MIT Bauhaus book. Here is a highly enlarged image of the lower right corner showing the "B". See how buildup of ink in not a problem for 2 colors (200% coverage) but starts to lift on 3 colors (300% coverage). This only shows at extreme enlargement and with a bit of level tweaking in PhotoShop. When you see the book on the shelf, it was not noticeable to the untrained eye. I am sure the pressmen worked hard to keep it clean though! Pressmen in those days earned their keep adjusting keys, wash and dryers :-)

ChrisL