Creating illustrations for print requires knowhow when it
comes to preparing image file color for commercial printing. All commercially
printed material is produced by using “process” and/or “spot” color systems.
Software programs have built in color selection options to accommodate the
needs of commercial printing. Process color is easier to understand and use in file preparation,
because there is a standard color space provided for in software for it. Spot
color requires a different method for its use and image preparation. This is a
basic explanation of these color systems and how they are applied to be
helpful to digital illustrators who have not worked directly with commercial
printing companies.
Process Color
Also called CMYK, process color is cyan, magenta, yellow and
black. The term “process color” originated to classify a “process” of combining
dot mesh screening using the CMYK colors in combination to simulate a full
spectrum of other solid looking colors and a continuous tone appearance to
artwork and photographs. Solid colors are actually “optical” mixtures created
by combining flat screen meshes of CMYK. The most common use of process color
is in commercial printing where it is called “4-color process printing”. In basic
color theory terminology, process color is a subtractive color model, meaning that
the overlapping of CMYK colors subtracts from page brightness by absorbing
wavelengths of color.
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| The four ink colors used in process color printing. |
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| Enlargement of process color screens optically mixing to create colors. |
Spot Color
A spot color is a solid color of ink that is created by
mixing pigments. The term “spot” describes the common use for the ink for
printing solid shapes, i.e., spots of color. Spot color is most often used in
commercial printing where process color printing is unnecessary. For instance,
when printing stationery where only two colors are needed. It is also used to
enhance process color printing as a fifth, sixth, etc. additional color. An
example of this would be printing 4-color process illustrations in a brochure
and printing a fifth color for the logo of the company producing it. Every spot
color used in an illustration or design must be custom mixed as a solid color
by the printer in the correct quantity. There is no “optical” mixing of colors
as there is in process color printing.
Pantone® Matching System®
There are several different spot color ink systems used
throughout the world. In the US the primary system used is the Pantone Matching System. Pantone, now a subsidiary of X-Rite Inc., was founded in
1963. The Pantone Matching System, referred to as the “PMS” system, offers 1,677 distinct colors that are created from 15 Pantone base colors including white. The colors have been standardized by the use of the Pantone Formula Guide.
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| Pantone color selector resident in Adobe Photoshop. |
Using the guide and the base colors printers can mix any of the 1,677 inks with
complete accuracy, so it is possible for two or more printers to print a single
publication with remarkable color accuracy.
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| 15 Pantone base colors to mix all the inks in the Pantone Matching System. |
Pantone Base Colors
PANTONE
Yellow, PANTONE
Purple, PANTONE
Yellow 012, PANTONE
Violet, PANTONE
Orange 021, PANTONE
Blue 072, PANTONE
Warm Red, PANTONE Reflex Blue, PANTONE Red 032, PANTONE Process Blue, PANTONE Green, PANTONE Rubine Red, PANTONE
Rhodamine Red, PANTONE Black, plus
PANTONE Transparent White.
Pantone Color Bridge®
Although based on the Pantone Matching System, the Color
Bridge System was created by Pantone to show what the PMS solid color inks will
look like when printed using process colors. There can be substantial color
variance between Pantone solid colors and the CMYK interpretations of them due
to the narrower gamut of process color printing. (See below.) It is important to
note that colors specified in the Pantone Color Bridge will not be printed as
spot colors.
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| Pantone Color Bridge selector resident in Adobe Illustrator. |
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A comparison of the Pantone Color Bridge swatches on the left
to Pantone Matching System spot color swatches on the right.
Note the variance between the Bridge CMYK simulations and the actual
Pantone spot color swatches.
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Toyo
Ink®
Toyo Ink, another ink system now popular in the US, was
formed in Japan in 1907 and incorporated in 1979. Toyo offered alternative spot
colors to the universally adapted Pantone Matching System. It began to be specified by US designers and used by printers in the 1980's. The Toyo Color
Finder System offers 1050 ink color formulations that are arranged on the
Munsell color model. (See Digital Color
Spaces post under Lab Color.)
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| Toyo base colors for mixing all spot color inks in the Toyo Color Finder. |
Toyo Base Colors
TOYO Warm Red, TOYO
Rhodamine Red, TOYO
Purple, TOYO Violet, TOYO
Green, TOYO
Reflex Blue, TOYO Black Tint Base, TOYO
Opaque White, plus Process Yellow, Cyan and Magenta.
Additionally, Toyo manufactures Pantone base ink
colors for use with the Pantone Matching System, the difference being the
chemistry in Toyo inks. The pigment, vehicle, and additives used differ than
those used by Pantone.
HKS Ink®
A lesser know, custom color system containing
120 spot colors and 3250 tones, the HKS Ink System is in common use in Europe. It
was collaboratively developed by three companies, l.Hostmann-Steinberg,
Druckfarben, Kast + Ehinger Druckfarben, and H. Schmincke & Co.
TRUMATCH®
Introduced in 1990, TRUMATCH is another color
system based on the Munsell theory of color. It is a 4-process color to spot
color-matching system. Much the same as the Lab Color Space, the TRUMATCH Color
Finder system looks at color using a 3-dimensional construct of complimentary
color along a vertical luminosity scale. TRUMATCH claims to be more accurate
at matching process meshes to simulate solid color than standard digital
formula CMYK mixing. The accuracy comes from assigning
digital colors from actual CMYK printed samples rather than from RGB color
representations on-screen. The result is “wysiwyg” color.
FOCOLTONE®
Patented in 1984 in Wales, FOLCOLTONE stands for “FOur-COLor-TONEs”. The FOCOLTONE system uses the four
process colors, CMYK, as base inks for mixing solid colors to match 763 process
colors. The CMYK inks are used in varying percentages to make each of the 763 mixed
ink colors, 860 colors in Adobe Software. A FOCOLTONE color formula would be specified
in Grams and look like: 0 Cyan, 5.26 Magenta, 14.59
Yellow, 5.54 Black, and 74.61 Transparent White.
DIC
Formed in Japan in 1907 and incorporated in 1937 as Dainippon Printing
Ink Manufacturing, Most popular in Japan the DIC Color System Guide.
Very similar to the Toyo Color Finder system, DIC Color is a spot ink color system also based on Munsell color theory.
ANPA
The American Newspaper Publishers Association (ANPA) developed a palette of 300 spot colors for use in usage in newspapers with high volume press runs.
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| The ANPA index color selector. |
Additional Resources
The Pantone® Matching System© is available for reference use
on IOS devices from the iTunes store as “myPANTONE”. And though it is already
plugged into Adobe software applications, the ”DIC Colorguide” is available as
a free app from the iTunes store.
