Screen Printing:


Make Color Matching Easier

If you learn basic color properties and standardize your in-house inks, you can create a profitable and efficient process for color matching.

By Thomas Trimingham, Contributing Writer


Hues have properties with colors that are close to them and those that will mix with them to create other hues. Isolating the hue from value and saturation makes it easier to see how some colors can be easily matched while others may be more difficult.

June 27, 2013

Color matching doesn’t have to be a challenging part of the screen printing process. The main obstacles to fast and efficient color matching involve educating customers, previewing and preparing the artwork properly, and using the right tools to modify or mix inks properly. Once these hurdles are cleared, handling new color requests becomes a relatively simple matter.

Many of the difficulties in providing accurate color results can be prevented up front by first developing good color-
matching policies. A client will provide a design or logo and then, as an afterthought, say, “Oh yes! Make sure you match that accent color to Pantone 300 for me.”

This situation begs the question: What exactly are your shop’s policies for providing a color match on a printed T-shirt? Many printers are nervous about charging for matching an ink color and it is more common for this cost not to be added. If that’s the case, where does the extra cost factor in and who absorbs it? Depending on the agreement and relationship with the client, it may be possible to charge extra for color matching, or include the cost into either the art or the production setup costs. If there is no way to bill for the extra time required for color matching, then it is even more important that an efficient system be used to save time.

A great way to start developing skill with colors is to first address the concepts of color communication. Understanding basic  color vocabulary can be very useful in educating your clients on the different variables involved in matching a color.


COLOR TERMS
The fundamentals of color use are hue, value (or brightness), saturation, surface (gloss or matte) and opacity. Following are definitions and practical examples for each.

Hue: With regard to color, this term relates to the specific wavelength of light that the color reflects. If a color is royal blue, that means other colors are absorbed and the royal blue wavelength is reflected. This is important to understand because hues have certain properties with colors that are close to them and those that will mix with them to create other hues. Isolating the hue from value and saturation will make it easier to understand how some colors can be easily matched while others may be more difficult.

Value: This term also is known as color brightness and indicates how much white or black is in a specific color. Sometimes this concept is difficult for clients to understand without a visual reference. A certain hue of green may appear like a mint green, grass green or even a dark forest green — depending on the value — but this doesn’t mean it is different. The color is just brighter or darker. This term is important to understand because specific colors can sometimes be made on a garment graphic using existing inks if they are printed on a dark shirt, but other times it may not be possible because of the shirt’s hue and the underbase’s value.

One of the more perplexing color-matching issues in screen printing is that the value of the underbase print, or that of the shirt itself, often will influence the final color value of the ink on the garment, thus changing the color to a degree. This is why many screen printers use the term color “simulation” instead of color matching. It often is too difficult to accurately match a color that has been printed on bright white paper if the design is printed on a less-bright T-shirt background.

Saturation: This term refers to the amount of pigment contained in the ink that will be printed. One way to communicate the concept is to liken the amount of pigment in ink to little red balls suspended in a clear gel. Less pigment, means there are fewer balls in more of the base or gel. When the ink is printed onto a flat surface, these pigment balls will spread out and may also be more transparent if
the base is totally clear. A very saturated color often can be difficult to simulate using screen printing because the act of printing the ink onto the surface will thin the ink out. The pigments in screen printed ink are less reflective than paper inks due to the need for more opacity because a T-shirt’s surface is less bright.

Surface: The variable of an ink’s surface typically is a function of the base from which the ink is composed. The challenge to screen printers is that most ink systems match based on a gloss or coated formula, though some may allow for a matte finish as well. A gloss ink will provide a better medium for allowing the pigments to blend and interact due to the nature of the gel base in which they are suspended. Thus, it usually is the best choice if really bright, saturated colors are needed.

The best way to match a matte color is to use a printed sample of the primary and secondary colors as a reference, then compare them to the identical gloss finish colors and see what the apparent color shifts may be. Matte-finish ink usually will have a base that has some level of white in it so it will likely need a different mixing formula to reach the same final hue as a gloss color. Good mixing systems will make allowances for this variation and they should still work well, but the real truth is always in a printed sample.

Opacity: In some ways, a screen printing ink’s opacity can be the issue that has the most variables. Opacity refers to how transparent the color is. Very transparent ink tends to mix well with other colors and produce bright hues, but these colors may shift depending on the garment color. An ink’s opacity also can become an issue when it is printed through a higher mesh count or onto an underbase print because, at that point, the pigment may shift to a different color.

The easiest way to combat this problem is to test a short selection of colors that are commonly requested and then have them printed as samples on and off of an underbase to determine your ink system’s opacity. Even when this is properly done, you must be aware of how a specific ink formula may become more or less opaque, depending on the amount of white that is added during composition.

BEFORE MIXING
There is a fine line between educating clients and making them feel like they need to be nitpicky about the colors being simulated. Cover the necessary basics (particularly if they have potential to provide repeat business) and keep the education to the specific colors required for the job. In this manner, it is possible to bring up potential issues in a way that illustrates both the advantages of screen printing and also prepares clients for a realistic amount of shift to the color, depending on the situation.

To make the most expedient use of a color-matching system, first define the stock inks your company wants clients to use when picking colors. An easy way to pick stock inks is to first talk with your ink supplier and see what typically is available in stock. Consider the most economical ink solution first for a list of commonly used ink colors. There are many ink systems on the market, including Wilflex, Rutland, Lancer and more. These companies will provide lists of the most commonly used inks for a beginning ink stock and also the least expensive solution for creating custom mixed inks.

A simple list of inks to start with could include about 30 basic colors. They should cover the larger portion of orders that are requested that don’t have specific colors and need to be matched to Pantone or other color references. A careful sales script should include questions that will help guide customers into using this color reference whenever possible. Of course, there will be many times when there is no choice but to mix the colors that are needed. In those situations, it comes down to how often this happens and finding the best solution.

COLOR-MATCHING SETUP
The idea behind mixing colors efficiently is to have all of the variables contained in the same location. Depending on the average number of inks that need to be mixed, it may or may not make sense to have a computer available — set up in close proximity to the ink station — with the ink-mixing software on it.

A great way to set up a fast color-matching area is to consider a location that is away from normal ink and screen traffic flow, setting up the regular inks in one area and the ink-mixing station in another area. The basic equipment needed is a durable scale (best if it goes down to .01 grams) that is easy to clean; all the necessary ink components (the base may be separate from the pigments or it may be a finished ink system that is included in a premixed selection
of mixing colors); a supply of empty quart- and gallon-sized containers; mixing blades to scoop and stir inks; and some solvent-
resistant labels to mark the final mixed
colors.

Once a screen printer has all the right pieces of equipment to set up a mixing area, he can address how to make the process faster and more accurate. Keep everything you need to mix ink within quick reach to decrease downtime. A lot of printers will put the scale on a table with a solvent-resistant top and add a shelf just above it to hold the ink components.

The next time mixed ink needs to be rushed out to the press floor, some simple preparations can save you considerable time and effort if the mixing area is staged properly and the best method of mixing already is established.

Thomas Trimingham has been working in screen printing for more than 21 years as an industry consultant, freelance artist and high-end separator. He is an award-winning illustrator, designer and author of more than 100 articles on screen printing art and separations. For more information or to comment on this article, contact Thomas through screenprintingartist.com.


Increase Your Mixing Speed

1. 
Label all ink components with easy-to-see oversized labels that are solvent-resistant. You can spend a surprising amount of time simply searching for the right pigment if it only includes the original label.

2. 
Have a spatula for each ink component so you don’t have to clean one after each use or waste time searching for one.

3. 
Keep all your ink-mixing components separate from your normal ink stock. This way, the general area is already narrowed down for finding the color you need.

4. 
Keep empty buckets available. You can waste a lot of time trying to find a container to mix ink when you’re under the gun.

5. 
Mark each bucket when it gets below half-full and order a new one on the next ordering cycle. One of the most frustrating things is rushing to mix ink and not having enough of a certain color that you need to make the formula work.

6. 
Keep mixing gloves handy and clean. This may seem obvious, but designating a pair of gloves just for ink mixing and ensuring they always are available will keep the ink where it needs to be and prevent you from tracking it around the shop by accident.