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to not specifically create the palette using

the designated printing colors. If the graph-

ics are created without a prepared palette,

colors not intended to print are unintention-

ally added to the palette. Actions that can

unintentionally add colors to the palette are:

• Creating a blend from one spot color to

another.

• Adding or pasting in clip art that has

additional colors in it.

• Naming one color (such as Pantone 259

purple) two or three different names.

• Creating graphics using colors that look

good but are not one of the specified

print colors.

When deciding on the number of colors in

one item, the designer should consider what

the item would look like when it is out of reg-

ister. Misregistration of two or more inks can

ruin a beautiful design faster than anything

else in the printing process. There is a way

for the designer to evaluate the out-of-regis-

ter look. Each color used must be on its own

layer, then select all items on one layer and

move in one direction — the amount of the

trap. The result simulates the worst-case

look of the graphics when printed.

If the designer chooses to create a custom

color, the color should be designated in the

drawing program as a spot color. Custom

colors are not always designated in a draw-

ing program as a spot color, but instead

default to a process color “breakdown”.

When this default happens, the spot color

separates into the process color match

instead of being one spot color on the final

film. It is recommended that a designer use

the Pantone library provided with all draw-

ing applications.

When choosing a color palette for a pro-

ject, it is necessary to know the number and

color of inks that will print. It can be expen-

sive and difficult for a production artist to

“clean-up” an electronic artwork file that

should print with five colors, but ends up

with 22 colors as a result of how the colors

were created in the artwork. An artist should

use only the specified printing ink colors. In

addition, colors should not be duplicated

and renamed. Extra, unwanted colors can be

inadvertently added to a graphics file when

artwork from one application is cut and

pasted or imported into a file in a different

application. Even when precautions are

taken, unwanted spot colors can appear in

the file. For example, if the file is in Adobe

Illustrator, one way to eliminate these colors

is to select objects from the menu, then

select custom colors and delete all unused

colors.

Tints. Extra colors or inks can also be inad-

vertently added to an artwork file when

spot-color tints are incorrectly created. To

create a spot tint correctly, select the spot

color and define a percentage of that color.

Spot tints should not be created by selecting

a new color to create the tint. If a new color

is selected to create the tint, it will create an

additional color that will separate onto its

own film, rather than appear on the original

spot-color film. During the final design

review, any colors that are not one of the

specified printing colors and are existing in

the graphic file should be eliminated.

Of course, many times the designer and

separator work together to decide how cer-

DESIGN 47

When choosing a color

palette for a project, it is

necessary to know the

number and color of inks

that will print. It can be

expensive and difficult

for a production artist to

“clean-up” an electronic

artwork file that should

print with five colors, but

instead has 22 colors as

a result from how the

colors were created in

the artwork.

Process Color

Custom Gradient

Custom Color

Custom Pattern Fill

48 FLEXOGRAPHY: PRINCIPLES & PRACTICES

tain effects and colors can be achieved using

available process and spot colors. When a

special color is needed, the designer leaves an

extra color in the design, so the separator can

determine how it should be created. This is

only done when the designer and separator

have communicated and agreed upon this

action plan. The designer must specify the

special color as “match color PMS 259” for

example, or whatever the match is supposed

to be.

ith the production art

completed, it’s ready for

the platemaker. Now is

the time, before the

expense of platemak-

ing, to get final approval

of all copy, positioning and color. Depending

on the specific printer, interdepartmental as

well as customer approval may be required.

Usually, you can save time if the original pro-

duction art is retained in-house and copies

forwarded for customer approval. For pur-

poses of approving the copy and positioning

of line work, ink jet or laser copies are often

sufficient.

COLOR PROOFING

Color proofs, better known as contract

proofs, are used for customer approval

throughout the entire design, prepress and

print process. The proof is used to represent

what the graphics will look like when print-

ed. A proof is a very useful and inexpensive

way to determine if any changes should be

made to graphic color, placement, text, trap,

dot-gain compensation and much more.

Unfortunately, many contract proofs are

produced on devices that are not calibrated

or even capable of reproducing a proof that

will match the press result. Consumer prod-

uct companies and designers are approving

and expecting the final print to match this

proof, which doesn’t happen in many cases.

The most common issue with contract

proofs is that they are made to offset and not

flexo specifications. The proofing stage

needs to be set up for flexo specifications.

Although the designer does not usually pro-

duce the proof that is used in the approval

stages, he/she can take charge of providing

the correct flexo information to those mak-

ing the proof. The designer should work

closely with the flexo separator when deter-

mining how the contract proof should be

made. Some guidelines to follow when using

an analog or digital proofing system are:

• Use flexo target densities.

• Make sure the correct color of the sub-

strate is compensated for or simulated.

• Use the correct flexo tonal values for

minimum highlight and maximum

shadow dots.

• Do whatever else the separator or print-

er suggests.

DESIGN 49

Final Approval

50 FLEXOGRAPHY: PRINCIPLES & PRACTICES

Programs and Applications

he designer needs to focus on

the printability of the design,

and at the same time, create files

that can be edited. With all of the

software bells and whistles

available today, it is very easy to

create graphics that are difficult for the sep-

arator to pull apart and separate, and to

make compensations for dot gain and trap.

Computer programs or applications are

the tools that designers use to create elec-

tronic artwork, the way a carpenter uses

saws, hammers and awls to create furniture

or cabinetry. And like a good carpenter, a

good designer will be familiar with many of

the tools available for creating artwork in

the desktop environment. He/she will be

aware what each application offers in fea-

tures and options to accomplish a specific

project. A carpenter can’t create every piece

of woodwork with just a hammer and a

designer shouldn’t try to create every design

with just one application. While many pro-

grams available today are similar, all offer

unique features or options that set them

apart from other programs. Some programs

are specifically developed to handle page

layout with graphics. Some are more applic-

able for packaging graphics and some are

ideal for working on scanned graphics.

Packaging graphics are usually created and

completed in a drawing program.

The designer must use software programs

that allow for easy and efficient graphics cre-

ation. These programs also must allow the

separator to easily separate and compensate

for flexo variables. Choosing software that

works for both processes should not be an

issue if the designer and separator have good

communication procedures in place.

Regardless of which application the

designer chooses to create artwork, the

application is a tool that the designer must

skillfully use so that the completed project

can be effectively separated. Artwork files

that are successfully separated are usually

very simple files. That is not to say that the

artwork design is simplistic or unsophisti-

cated. Simple files are files that are built or

created in an uncomplicated manner.

LAYERS

The layer function is available in most

desktop applications. Layers are a useful

tool for organizing elements in an artwork

file (Figure

). Some graphics are simple

with very few elements and do not justify the

time it takes to create layers for varying ele-

ments. Other graphics can be quite complex

by incorporating many different graphic ele-

ments, such as a variety of flavors or special

banner information. These graphics can eas-

ily cause confusion, and if not organized

accurately, they can result in the wrong

graphic elements appearing on the separa-

tor’s proof. With complex graphics, layering

can be very useful. Layers used in creating

an artwork file can make editing or out-

putting the correct color separations or fla-

vor separations very efficient.

Separate layers can be created to organize

an artwork file in the following manner:

• Die line. This layer indicates the overall

shape and layout of the packaging

design, and should be created in a

color called “die line”.

• Graphics. This layer contains the main

portion of the overall design and any

common artwork. It is not unusual for

a packaging project to have different

versions of the same package. If all

elements that are common to the dif-

ferent versions are on one layer, mod-

ifying the file to output a specific ver-

sion of the package becomes easy.

• Additional versions. This is where art-

work unique to a specific version of the

package should be placed.

• Annotation. This layer is used for any

comments or remarks relevant to the

project, as well as for the graphic lay-

ering information.

When designing a project consisting of lay-

ers, a designer should be aware of what ele-

ment(s) are being placed on which layer(s).

To check the contents of the layers, the

designer should deactivate the display of all

layers and then display each layer, one at a

time. This procedure is a good way to avoid

a print rerun caused by misplacing an impor-

tant element on the unintended layer.

A designer should also try to organize the

file so that it doesn’t contain excessive lay-

ers or layers with confusing names.

Remember that a production artist is going

to have to output this file after the designer

is finished with it. It is not unusual to have a

last-minute change to the project that a pro-

duction artist will have to make in the file.

Layers that have confusing names or that are

excessive in numbers can make editing the

file very difficult and time consuming.

DESIGN 51

Layers are created to

organize an artwork file

in the following manner:

die, annotation, image,

harvest, strawberry.

Barcode

Here

Common Copy Label Variations

52 FLEXOGRAPHY: PRINCIPLES & PRACTICES

DRAWING PROGRAMS

Drawing programs utilize vectors (mathe-

matical information of a point and line in

space, defined by its magnitude and direc-

tion). Vector-based or object-oriented art-

work consists of points that defines how the

lines between them should act – as straight

lines, arcs or Bezier curves. The shapes

defined by the lines can then be filled with or

without color (Figure

Several drawing programs are available

for the desktop publisher – the two most

popular applications are Adobe Illustrator

and Macromedia FreeHand. Vector-based

programs create object-oriented art with the

following qualities:

• Objects are perpetually editable.

• Objects print at the highest possible res-

olution.

• Objects maintain their quality and don’t

degrade like bitmapped images.

• Objects are infinitely scaleable.

• Graphics are very small compared to

bitmapped graphics.

• Die lines can be created in vector-based

software that can then be forwarded to

the diemaker.

Other features of these drawing programs

include the ability to create blends or

vignettes and edit raster images.

The designer should find out what format

the separator prefers for placing or import-

ing graphics into a drawing program. If using

Adobe Illustrator, for example, it is recom-

mended to use only placed EPSs, especially

when working with process color graphics.

When a file has an embedded TIFF file,

instead of a placed EPS, the separator may

have to re-raster the image in PhotoShop to

color correct it. The edited file is then placed

back into Illustrator as an EPS. This lengthy

procedure increases time expended on cor-

recting the file and increases prepress costs.

When designing with a placed EPS, verify

that the clipping path is included in the

Illustrator document, especially if the image

has to trap to a background or gradient. This

procedure enables the separator to quickly

trap the Illustrator file and can be done as

follows :

1. Export the clipping path to Illustrator

from within PhotoShop.

2. Save the graphic as an EPS.

3. Open the Illustrator file with the

exported path, which opens it with

crop marks and indicates the docu-

ment boundary.

4. View the image in the artwork mode

showing the rulers and choose any

corner.

5. Line up two guides – one vertical and

one horizontal. Make sure the general

preference is set to “snap to point”.

6. Place the EPS by selecting and drag-

ging from one corner; the graphic will

snap and line up exactly with the path.

PAGE LAYOUT PROGRAMS

As with the drawing programs, there are

several applications available in the desktop

environment designated as page layout pro-

grams. Two major applications for page lay-

out are QuarkXpress and Adobe Pagemaker.

As the title suggests, page layout programs

are designed for laying out documents that

Drawing programs uti-

lize vectors, i.e., points

that define how the lines

between them should

act – as straight lines,

arcs or Bezier curves.

can be of a single page or of multiple pages.

The primary function of the page layout pro-

gram is to create a layout that has text with

placed graphics to complete the file. The

tools available for assembly and manipula-

tion are very extensive for handling large

bodies of text. While the functionality of

these page layout programs may be very

impressive when producing files for the pub-

lishing industry, they have few tools to

address packaging graphics. These applica-

tions were designed to create layouts by

flowing text from page to page and dropping

in graphics as necessary. Most packaging

projects are graphic intensive, contain bar

codes, have very little text and must be

applied to diecut structures of unusual

shapes. Page layout programs are not usual-

ly designed to handle all of the various items

that are required of packaging.

The focus of page layout applications is to

effectively handle type, not graphics. Some

simple graphic elements can be created in

page layout programs, but the applications

were not originally designed to create graph-

ics. Additional bodies of text can be created

and modified in a page layout program and

then imported into the drawing program.

Importing text from the page layout program

to the drawing program is especially recom-

mended if 80% of the artwork is graphics and

the remainder is text, some of which may be

created in the drawing program. It is an

unnecessary, time-consuming step to import

the bulk of artwork into a page layout pro-

gram in order to add a few lines of text.

Some designers import the bulk of artwork

into a page layout program because of the

misconception that the page layout program

is needed to output to a digital color proofer.

Actually, all desktop applications have the

ability to output to a digital color proofer. If

TIFF images are used in a page layout pro-

gram, it is recommended that the image is to

cropped or rotated in the native application,

such as PhotoShop or Illustrator, thus

decreasing the file size. Be sure to includea

bleed area of 0.125" for the separator to

work with.

Recent releases of page layout programs,

has added the ability to create graphics with-

in the program. Though this may seem like an

excellent addition, in reality these new fea-

tures can cause a prepress processing prob-

lem. Many of the new features are automated;

therefore the level of control for editing is

severely restricted or impossible.

RASTER IMAGE PROGRAMS

Raster image applications such as Adobe

PhotoShop provide a means to manipulate

scanned photographs in the desktop envi-

ronment. Raster image programs are excel-

lent tools for cleaning scanned images, uti-

lizing GCR/UCR, compensating for press

characteristics, adjusting color to match the

original and even converting the file formats

of digital artwork. When using a raster image

program to modify scanned artwork, it is

best if all modifications and manipulations

of the image are handled in the raster pro-

gram. Scaling, cropping, clipping paths,

color application and rotations are best dealt

with in the raster program, rather than plac-

ing and manipulating the scanned artwork in

a drawing or page layout program.

DESIGN 53

Raster programs use

pixels to define the

image.

54 FLEXOGRAPHY: PRINCIPLES & PRACTICES

Image manipulation

progams offer a variety

of filters to achieve

interesting effects in

addition to photo

retouching and color

correction.

Original Image

Crosshatch Cutout

Dry Brush

Glowing Edges Halftone

Lighting Mosaic Pointillism

Posturize Ripple Spatter

Texture Twirl Watercolor

Raster programs use pixels to define

images (Figure

). These pixels or squares

define all data in a bitmapped graphic. Every

pixel can have different colors in a

bitmapped graphic. In a high-resolution

graphic with hundreds of pixels per inch,

this capability allows for the reproduction of

subtle shading and tonal changes.

A raster program can provide the designer

with many creative avenues for the look of

the type. But, this type cannot be edited and

makes the type file large compared to type

files created from a font in a drawing pro-

gram. Therefore, a raster program should

only be used for small amounts of text and

effects that cannot be created in other pro-

grams. There are several capable and cre-

ative special effects that can be used in a

raster program. When utilizing these effects,

keep in mind the flexo criteria (parameters)

within which the design must be created.

SPECIAL EFFECTS

In addition to photo-retouching and color-

correcting tools, image-manipulation pro-

grams such as Adobe PhotoShop offer a

large variety of visual effects. These built-in

features have been enhanced and supple-

mented over time by third-party software

plug-ins. Figure

shows the variations

created using various filters. These special

effects may take an image so far from its orig-

inal form, that the final result is an image that

itself appears entirely original.

INTEGRATING PROGRAMS

A designer should always remember that

after the artwork is created, the electronic

file has to go through a RIPping or transla-

tion process in order to output to film.

During this process, the electronic artwork

file is essentially pulled apart, converted into

binary language and then put back together

in a manner such that the imagesetter can

receive the data. It is during the RIP that

many problems occur from the electronic

artwork. Files that are built cleanly and sim-

ply are the most successful files to translate

during the RIP stage.

Receiving a package and opening the

package is comparable to the first stage of

the RIP – the electronic file is received and

opened. But before a file can be translated,

the RIP must know what is in the file; data

such as bar codes, scanned images, text, die

lines, gradations, illustrations, placed graph-

ics and more. All of this electronic data can

confuse the RIP. This first stage of the

process is referred to as file nesting. When

building an electronic artwork file, a design-

er should try to create the design in as few

desktop applications as possible.

If the bulk of the design is built with graph-

ics, the final electronic file should remain in

the drawing program in which the artwork

was created. Files that are imported into the

main artwork from raster image applications

should be imported as EPS files and should

not require further manipulation in the draw-

ing program. Any resizing, rotation or color

adjustments should be applied to the

imported artwork in the application originat-

ing the artwork. This guideline is also true of

any text that is imported from page layout

applications.

Another step to avoid is to create artwork

in a drawing program, save it as an EPS file

and then re-import it into the same drawing

program. The EPS file from a drawing pro-

gram can be opened and cut and pasted into

the design layout. Placing an EPS file into

the file’s native application creates unneces-

sary steps and data for the RIP. The designer

who copies and pastes the EPS file in the

native program creates a stable electronic

artwork file that will RIP successfully. Files

that don’t RIP successfully sometimes

require an entire rebuild of the artwork file,

which can add significant time and cost to

the entire project’s progress. The cleaner

DESIGN 55

56 FLEXOGRAPHY: PRINCIPLES & PRACTICES

and more simple a file is built, the fewer

problems it will have during the prepress

processing and the more likely it is to suc-

cessfully print.

COLOR MANAGEMENT PROGRAMS

With the advent of reasonably priced

instrumentation, it has become possible to

measure and control color using CIELab

color space. Basically this means measuring

color in the same way that people perceive

color. Instead of a set of CMYK values, a

color is described in terms of the three char-

acteristics that people distinguish in color:

hue (red, green, blue, etc), chroma (the satu-

ration or purity of the color, where gray has

zero or no chroma), and lightness (the

brightness of a color, where black is at one

end of the scale and white at the other).

Color management programs are tools

that apply this technology to the workflow

(Figure

). Applications can range from

CMYK-to-CMYK conversions which match

two output devices, such as a proofer to a

press, all the way to the full-scale integration

of the technology to implement what is

known as device-independent color. The lat-

ter term refers to color that is measured and

managed from an absolute measurement

point of view. In the CIELab color space or

color description, any color has a unique

value given by three numbers. If that partic-

ular color is to be reproduced, the charac-

teristics of the output device must be

known. These characteristics are called the

profile, or more specifically, the ICC profile

of that device. If all input and output devices

are characterized in this way, color can be

specified and reproduced in terms of these

“absolute” values.

By the late 1990’s, color management has

received a lot of attention and is becoming

more widely used. It is by no means as

prevalent as some of the more mature tech-

nologies, such as Postscript, for example.

Many different “workflows” still exist and

will likely continue to exist as the technolo-

gy matures and becomes the accepted way

of working with color from creation to ink

on substrate.

Applications of color

management technology

can range from CMYK-

to-CMYK conversions

which match four output

devices, such as a

proofer to a press, all

the way to the full-scale

integration of the tech-

nology to implement

what is known as

device-independent

color.

CPU

ORIGINAL

Monitor

Thermal

Transfer

Color

Laser

Imagesetter