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Prepressure covers design techniques, PDF, PostScript, fonts, JDF and numerous other prepress topics that have to do with printed communication and graphic arts

Special offset printing inks

Regular process inks or spot color inks can have unique properties. They can be extra glossy, resistant to abrasion, low-odor, dry fast under UV light, etc and of course, they are usually optimized for a specific printing process and/or type of substrate. There are however also special inks. These are often used to make advertising material, packaging and labels stand out. Some of them are used for security purposes.

Thermochromic inks
These inks either change color or become transparent when temperatures increase or decrease. There are inks that will keep changing color or transparency and others that will only change once. Thermochromic inks are used in toys, battery indicators and some types of thermometers. They are also used frequently in packaging, to show commercial messages or to show the packaged product is warm or cold enough.

Metalic inks
This inks have a metal-like character. They contain metallic particles that rise to the surface after printing, reflecting light and creating a metallic sheen that simulates zink, copper, gold or silver. Inks that aim to create a metallic sparkle effect are called glitter inks.

Mirror inks
Mirror inks are a special kind of metallic inks. When printed on the reverse side of a transparent substrate like glass, polyester or poly-carbonate you achieve a mirror effect. This can be done with offset but also screen printing.

Pearlescent inks
The metal oxide based pigments in these inks give a characteristic gloss to the printed image that is comparable to the iridescent gloss of pearls.

Watermark imitation inks
As the name implies these colorless inks imitate a watermark.

Scented inks
These inks give off a scent when the printed surface is scratched. The inks contains tiny nano-sized particles that encapsulate a fragrance. Scratching the printed surface tears open the capsules so that the scent is released.

Scratch-off inks
Instant win lottery tickets have a thick layer of scratch-off ink applied. Scratch off ink is also used to hide secrets codes for contests on beverage cans or other types of packaging. First a release varnish or UV coating is printed and then the scratch-off ink layer is printed on top. This can be done with screen printing as well as offset lithography. In offset you may have to print multiple layers to get a good result.

Magnetic inks
These inks are used as a security measure on checks and other high value documents. They contain particles of a magnetic substance whose presence can be detected by magnetic sensors. A counterfeit copy produced using regular inks will not pass a validation by an MICR (magnetic ink character recognition) reader.

Luminescent inks
These have two completely different uses:
Luminescence security inks, which are sometimes called marking inks
marking inks or UV/IR excitation inks, light up when exposed to ultraviolet or infrared light. They are used as a security measure on banknotes and other high value printed documents.
A bit more frivolous are photo luminous glow-in-the-dark inks, which temporarily emit a weak light in the dark.

Closing shortly: GWG 2017 PDF survey

The Ghent Workgroup is an industry association dedicated to advancing the print, publishing and packaging industries. They’ve set up a survey about the use of PDF to better understand how processes have changed over the years, which specifications are being adopted, and how workflows vary. Please participate to help them improve the solutions they offer and maybe win a price along the way.

PDF survey

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Friday flashback: Two birthdays in a row, 1987 really was a fruitful year –

QuarkXpress 1.0 splash screen

PDF/X summary

The PDF Association offers a free 17-page guide to the PDF/X file format, called PDF/X in a nutshell. That topic is also covered in some detail in the special PDF flavors section of my PDF overview pages.

PDF/X in a nutshell

Not bad for an industry that some consider ‘dead’

Every day 520 million newspapers are read worldwide.

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Friday flashback: I’m moving to San Seriffe to marry the daughter of Pierre Myriad –

San Seriffe


‘The quick brown fox jumps over the lazy dog’ is a pangram, a sentence that uses every letter of the alphabet at least once. Pangrams are frequently used to show typefaces, which is how I stumbled across that sentence. Other examples of pangrams are ‘Pack my box with five dozen liquor jugs’, ‘The jay, pig, fox, zebra, and my wolves quack’ and ‘Five quacking zephyrs jolt my wax bed’. The challenge with pangrams is to create one that is as short as possible but still makes sense. I gave it a go with this tool and came up with ‘My sexy wife just came by to laugh at a dozen very quirky pangrams’. Not bad but certainly no record breaker.

In 2007 a quick brown fox did jump over a lazy dog. You can watch the full video here and of course, someone turned it into an animated GIF.


Font poems

I’ve started adding examples of typefaces to pages. First up are the pages on 1966, 1977Arial & Caslon.

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Friday flashback: One day my boss had me trained on a Repromaster 2200 to learn ‘the old ways’ –

Agfa-Gevaert Repromaster repro camera

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Friday flashback: In those days, men were men and presses were made of German metal –

Heidelberger Zylinder 54x72 cm offset press


Rich black is black to which cyan or magenta is added to make it more dense, more black. Below is an example of what happens if you forget to do this. Look at the hair of the guy which is grayish wherever it does not overprint any of the other elements. The irony is that this image is taken from the cover of a brochure for an introduction to graphic arts. The training promises to teach businesses how to spot quality issues and is taught by a well-known professor. I guess it did not take him long to spot the problem since a fixed version of the same graphic appeared in all subsequent brochures.

rich black missing

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Friday flashback: David Pelham creates the iconic book cover for ‘A Clockwork Orange’ –

David Pelham book cover

The phototypesetting era

I’ve lately gotten interested in phototypesetting – the typesetting systems from the 60’s, 70’s and early 80’s. Expect some more updates of the history of prepress pages about that era.

Compugraphic Compuwriter II

A beautiful bookstore

Dezeen published a fascinating series of pictures of the Zhongshuge bookshop in Yangzhou, China. Books are displayed in a tunnel-like entrance with a mirror floor that adds to the eerie ambiance of the place. It is encouraging to see such designs now that my own favorite bookstore has gone bankrupt.

Zhongshuge bookshop in Yangzhou, China


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25 May 2017

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