Mixing with opaque white vs. translucent white

I have read some people having inking issues when mixing translucent white with black ink to achieve a grey color. But that the inking issues are resolved when mixing with opaque white instead.

I am trying to venture out and mix my own colors. Should I worry about this problem I mentioned above? When should I use opaque white instead of translucent? Whats the difference really?

For your information I plan to use the ink on photopolymer plates if that makes a difference.

Log in to reply   4 replies so far

You actually answered your own question. Do you want your ink to appear opaque or translucent? Opaque colors reflect light that hits the surface, and transparent colors allow the light through the pigment dispersion and allow the paper to be a factor in the color. Overprinting colors with transparent inks will cause a third color, where opaque inks are more problematic in that respect. Some pigments are naturally more opaque than others, but that has to do with the properties of the pigments rather than the ink. Transparent inks look watered down, and opaque inks tend to look bolder, more poster-like. It depends on what kind of effect you are trying to achieve.

Paul

Paul

thanks for your explanation. That makes since. I see the difference.

So in your experience is there any difference with regard to inking issues with the one versus the other? I think that was my deeper concern and not knowing the difference in the choice just complicated it.

Thanks

A lot of people expect the color of transparent ink to be denser than it ultimately looks on paper, and try to make up for it by adding more ink (which doesn’t help). I made posters for years and have used more opaque white than I care to think about. I have a project now, printing some stationery and labels on a brown stock that is darker than average kraft paper. As part of the design I plan to print a rectangle of warm red ink (opaque) overprinted with black type. If I were to print the rectangle without opacity it wouldn’t cover the paper with one pass; with transparent medium it would look orange-brown. To get the coverage necessary for my goal I must use opaque white in a very small amount (so as not to change the intensity of the red), but enough to block the background color.

Opaque white when mixed with a color disperses the pigment molecules, moving them farther apart so that to the eye the color appears lighter, but it reflects light in the visual spectrum making the ink film almost appear to float on the surface of the paper. This is very useful with posters, because you want the color to ‘jump’ off of the page. It is also useful when using initials on a page of black type, making the initial ‘pop’.

Transparent ink disperses the pigment in a clear medium, which makes it possible to see through the ink to the paper, which is why it has a watered-down look. This is especially useful in four-color work from half-tones where it is very important to print a blue over yellow for a green tint, or a certain blue over red for a brown.

This brings the necessity of understanding the coloring qualities of the different pigments used in mixing process colors, or the standard PMS (Pantone Matching System) color mixing charts. There are essentially 12 different mixing colors (not counting opaque and transparent whites, and metallics) with different properties that, when combined, create an infinite number of colors.

If you really want to understand the mixing and interaction of colors I very much recommend the book “Blue and Yellow Don’t Make Green” written by Michael Wilcox, and available online:

http://schoolofcolor.com/acatalog/Blue_and_Yellow.html

Wilcox has basically (but not exactly) adapted the formula used by printers since the mid-1950s to a limited pallette of color for artists using oil and water based colors. He explains it better than any printing book I have encountered, and his understanding of color is very well researched. Since pigments for the paint and ink industries are standardized, a lot of the information is transferable to our usage. There is a lot to learn about color, and it is sadly neglected by designers and printers who often operate without really understanding why one combination works, and another doesn’t.

Paul

Paul that is absolutely what I needed to know. I will read that reference work. Thank you very much.