Pantone Ink Mixing with VanSon Rubber Base Plus

The Color Bridge (formerly Solid-to-Process) is for when you have to simulate a Pantone color using 4-color process printing. What you want is the Pantone Formula Guide, which is for mixing Pantone color inks for spot color printing, and gives the “recipe” for the colors from the ten or so Pantone basic colors including the Rubine, Rhodamine, & Warm reds, and Reflex & Process blues you mention. Once you get the Formula Guide, this should be clear; if not, or you need to get started sooner, let me know.

Dave (the Ink in Tubes guy)

Thank you! This makes sense! I recall now why I got the bridge books and not the formula. I was only contracting out the printing and only needed a book to allow me to see the correct colors on my screen. Now that I am letterpressing and trying to use the Pantone Colors, I guess I need the formula book.

I actually work at the Rochester Institute of Technology and we do the ink mixing for HP and Pantone colors. We have a system called IMS (Ink Mixing System) that gives us the formulas for all of the Pantone colors. As far as mixing VanSon ink to the Pantone books that you have, you will not get exactly what the Pantone book says. I also proof the Pantone colors where I have seen that if for instance you have a light color you are trying to hit, the IMS tells us to add a dark color, but in some circumstances, it knocks the color out of whack! This is basically said because the smallest amount over or under for each color could mean the difference. If you have any other questions regarding Pantone and ink mixing, I can help!

Dan

Dan — Good to know there is a color expert here! I just picked up the Pantone Formula Books today, so let’s see how this goes!!!

This tip is wholly unscientific, but it may help you.
I mix ink with Van Son rubber based ink following the formulas in the Pantone matte guide (got the matte guide free from my graphic designer sister. Hope to move to the uncoated guide soon).
I use the formulas as a starting guide and mix by eye using dots of ink. The thing I have to remember about ink mixing for letterpress is that the dark colors (especially process blue and black) are really dark and I usually need way more mixing white than is called for.
Recently I’ve found that I can mix most accurately by choosing a color from the pantone book and then mix using the formula that’s two shades lighter.
This works pretty well for me. I know other printers use opaque white instead of transparent white, so you could try that too. I’ve asked for opaque white for Christmas, so I’m hoping to give it a shot.
Of course my clients are myself and friends so it doesn’t matter if my ink color comes out almost right as opposed to exactly right.

Along with matching visually, we use a spectrophotometer. This device reads and gives you Lab values. You can use the Pantone book as a reference and use the color that you are mixing (printed version) and scan that vs. the reference. This gives you the difference between the two colors.

For instance, if you have Lab values where you L (lightness) is high, you a value is high, and you b value is low, then you would want to look on the Lab image posted. This will let you know what color to add, based on the Lab values you are getting. Like in the example I gave, if L is high then add black, if a is high then add green, and if b is low then add yellow. Hope this helps!

cie_lab_color_space.jpg

One of the main things to keep in mind here is that the inks are all transparent, at least to some degree, so the ink “color” depends on light being reflected from the substrate underneath the ink, and the ink film thickness will greatly affect the color. The Pantone system is designed for offset printing, and since letterpress printing puts down a thicker layer of ink, colors will print darker. Mixing a color a shade or two lighter than what you want and/or using Opaque White (if there’s white in the formula) are both ways of compensating for the thicker ink film of letterpress. The Pantone system is an excellent starting point, and can work quite well, but there are simply too many variables for any system to work perfectly. Even if we all had spectrophotometers and could mix a “perfect” color of ink, the press and the paper we print on will make it vary.

BTW, for anyone who needs a relatively small amount of Opaque White, I’m putting some in 1/4-lb. tubes and I’ll have it available soon.

Dave (the Ink in Tubes guy)