Photo purchased from … www.depositphotos.com

At the top of this article you will see a glorious photo taken at sunset. The purples and yellows are rich and vibrant. The same intensity might characterize a photo of a verdant meadow. There are certain “memory colors” that we depend on seeing. They have to be “right.” When they are not (within a certain tolerance), that’s a problem.

In this light, I am sharing this question from a product designer working with a huge American entertainment brand. His is a story about color accuracy and consistency.

Here’s the client’s question:

“How do I spec a ‘white’ for printing on a metal base material? The problem is the white roll material comes from different sources even from the same manufacturer. The base color is then the background white to our graphic. It varies from gray to pink to antique white. None of these are good. I want to spec a white color to lay down as a spot color, so I can get consistent color from factory to factory. What is the solution? FYI, what I am referring to is a slow cooker metal wrap graphic.”

I called this designer immediately, and we spoke for a half hour.

The Backstory on the Manufacturing and Custom Printing Job

The product designer noted that four separate manufacturers produced the slow cookers in China. I first asked about consolidating the vendors, since maintaining consistency when working with multiple sources is difficult. The designer said that due to budgetary constraints, using one vendor was not an option.

Among other things (such as the manufacturers’ using different inks and different colored substrates), there was one other challenge. The three manufactured and printed items would be packaged together.

This was a problem. If you look closely at printed cereal boxes next to one another in the grocery store, you’ll see that from press run to press run (and presumably from printer to printer), there’s some—or a lot of–color variance. However, once you get the cereal home and are eating it, you usually forget the slight difference in packaging color.

This is because the human brain (in most people) cannot remember color for very long. Moreover, it is usually only when two items that differ in color are side by side that the difference stands out (unless they are memory colors, as described above).

This is where we had problems. The product designer’s slow cookers were all supposed to have red printing on a consistently colored white base. Since the colors differed slightly from manufacturer to manufacturer, and since the products were packaged side by side, the color variance was visible.

What I Suggested

My suggestions to the product designer fell into a number of categories:

Technology Used

I suggested that the product designer ask what technology the four separate Chinese manufacturers were using. For instance, my expectation is that they use either inkjet printing or custom screen printing. Granted, it is possible that some other technology is being used; however, knowing exactly how the manufacturers are adding color to the base material of the slow cookers is a good start.

Types of Ink Used

From there, I encouraged the product designer to find out what inks the manufacturers are using for the custom printing. For instance, are they using UV inks, since these can be printed on non-porous substrates? Also, presumably, if one manufacturer is using custom screen printing ink and another is using UV inkjet ink, there might be a variance, particularly if one color is a solid hue and another is a color build. It would probably be helpful as well if the product designer could determine whether the inks are solvent, eco-solvent, or, as noted above, UV inks.

The White-Ink Base Printing

The product designer’s comments about the variance in the color substrate raise an interesting point. One could lay down a base of opaque white and print a red color (presumably consistent among the four vendors) on the white. But what kind of white would be chosen?

I did a quick search online for white pigment (specifically the mineral content of various white inks). This is what I found: Zinc White, Titanium Dioxide, Zinc Sulfide, Lithopone, Alumina Hydrate, Calcium Carbonate, Blanc Fixe, Barytes, talc, silica, and China Clay. All of these minerals and other substances affect the perceived color of the base-white commercial printing.

Therefore, I encouraged the product designer to research what kind of white inks the four Chinese manufacturers have been using and then ensure that these will be consistent going forward.

Specifying and Proofing Color

With all of this in mind, I told the product designer that specifying color and proofing color were important elements of standardizing the colors of future jobs.

Regarding color specification, I encouraged the product designer to start with a successfully printed sample (with the color exactly as he wants it to be) and have a local printer check the color with a spectrophotometer. Unlike a printer’s densitometer, a spectrophotometer will actually determine the base white color and red surprinting ink and quantify these in numbers that will be recognizable (and able to be copied) by different commercial printing vendors associated with different manufacturers.

In addition, when printing ink on paper, I have always trusted “drawdowns.” These are made with your chosen ink smeared on your chosen paper substrate. You don’t see the photos or the actual typeset copy of your job, but you do see how the ink itself will look on the paper you have chosen. I suggested that the product designer ask whether a similar process was available from his manufacturers.

I also suggested that the product designer request a “contract proof” (of the white background and red lettering) before the final print run. Such a proof is considered an agreement between the client and the vendor. If the final print job does not match the contract proof, the printer has to make everything right or extend a discount.

I also suggested that the product designer send all commercial printing suppliers a package containing the shrink-wrapped slow cookers side by side. If it is obvious to him that the colors are off, it should also be obvious to the four Chinese printers. And it would be a good starting point for determining the cause and successful resolution of the problem.

Color and Light in General

Just to keep the discussion lively, I reminded the product designer that color is a function of light and vision. Colors look different under different lighting conditions. (For instance, at night a red car is gray.) To complicate matters, women apparently see color better than men. And, if you look at a colored object and then cover first one eye and then the other, your two eyes will see slightly different colors (at least mine do). So color is changeable and subjective.

That said, there are two terms I shared with the product designer that reference color consistency in both the commercial arts (and custom printing) and the fine arts. They are “metamerism” and “simultaneous contrast.”

Metamerism refers to the fact that some color patches appear to be either identical to one another or different from one another depending on the ambient light. Apparently this condition is more evident in grays, whites, and dark colors (so in the product designer’s case this might be a contributing factor).

Simultaneous contrast, which is closely related, refers to the fact that certain colors placed next to one another (complementary colors, for instance) will each affect how the other is perceived (as opposed to how they look when viewed separately). This speaks to how much our eyesight affects how our brain registers color. I personally think this is interesting but not as directly pertinent to the product designer’s situation with the white metal slow cookers with surprinted red type.

The Takeaway

Regarding the product designer producing slow cookers, I really didn’t know why he was having problems. But he did leave our conversation with a systematic approach to isolating, and then identifying and potentially resolving, the problems with the inconsistent industrial printing inks.

In your own work, if you are faced with a problem like this (with either ink on paper or ink on physical products), first determine the technology and inkset being used. Then consider the substrate (and give thought to printing a layer of opaque white under all other inks to provide a consistent base color).

Use precise, generally-agreed-upon conventions to communicate color (percentage of CMYK, for instance, and maybe even readings from a printer’s spectrophotometer).

Communicate color using printed samples (your chosen ink on your chosen substrate), and when in doubt ask for an ink drawdown. In addition, always request a contract proof.

All of these approaches (and especially seeking to resolve color fidelity issues by isolating all components of the custom printing process) will go a long way towards your success in printing beautiful, consistent color, even when you need to work with multiple commercial printing vendors.