Welcome to our guidelines for setting up art files for flexo printing.

Kopco Graphics, Inc. is dedicated to making your printed packaging design and purchase as easy as possible.  Use this guide from our printing experts when designing your artwork. 

• Sending us your file to review
• Dielines
• Colors
• Spot Colors
• Screens
• Gradients
• Metallic Inks
• CMYK Images
• Trapping
• Text
• Drop Shadows
• Fonts vs. Outlines
• UPC Codes
• File Format & Transfer
• Quick Reference Guide

Sending us your file to review
We encourage you to forward your art files to us for review.  We can review your design and help pinpoint any potential areas that might not reproduce well on press, giving you the opportunity to make adjustments that adhere to the integrity of your design prior to submitting the design for official artwork proofs.

Dielines
The key to successfully placing elements in a design is to start with an accurate template, or dieline.  A dieline is a diagram that clearly defines printable area in the artwork. Kopco Graphics supplies all dielines in Adobe Illustrator format unless otherwise requested.  Simple rounded corner rectangle (RCR) dielines are easy to create in Adobe Illustrator, however, please make sure to verify all specifications of size, corner radius, etc with your representative at Kopco Graphics.  Click here to download our starter template in CS2 format.

Colors
All designs should be kept to a maximum of ten colors, including white ink and varnish, if applicable.  Please include a color legend on any supplied proofs and make sure that the colors used in your design are labeled clearly and properly in your files.

Please note that “Process Black” ink, the “K” in CMYK, often appears as a dark gray when used independently in a design.  For this reason, we may need to run both a process black plate and a solid, or “line black,” plate so that we can utilize a more opaque black ink for elements that require a darker appearance. Please take this into consideration when determining the number of colors in your design.

Reproducing blues in CMYK.

Spot Colors
Although, Four Color Process printing is widely used in flexographic printing, there are many instances where the use of spot colors is preferable, or may be necessary.  Utilization of the Pantone Matching System (PMS) is recommended for maximum consistency.  For best results, use spot color in the following circumstances:

• Use a spot color when consistency of a specific element, such as a logo or background color, is important throughout a product line.

• Use a spot color for text, in order to maintain optimal legibility. (In most cases, black text should be printed in 100% K.)

• Spot colors should be utilized for elements that require vibrant color.  Please keep in mind that custom colors that are converted to CMYK do not always maintain their original brilliance or hue.

If we are to match a custom color or previous print of labels, please supply samples and any other materials necessary for color matching.

Screens
Combining screened and solid print areas on the same plate presents a challenge on press.  Enough ink must be applied to the plate to produce adequate density in the solid areas without applying too much ink, causing the ink to fill in the spaces between the dots of the screen.  When ink builds up in the spaces between the dots, the screened area will appear “dirty”.  If we identify a situation where combining screens and solid areas on the same plate may compromise your design, an alternative method may be suggested.

Gradients
The smallest dot that can be etched onto a flexographic printing plate may be a small as 1%, but may gain to as much as 12% on press due to the nature of the photopolymer plate material and the printing process.

This effect is most noticeable in gradients that are intended to have a soft gradation to 0%, which will stop gradating below 12% and will end in a hard line where the gradient drops to 0%.

Metallic Inks
While the use of imitation metallic inks can enhance a design, we do not recommend using tints, or screens of these inks.  The pigments used to create the metallic appearance have tendency to fill in the negative spaces in the screens, making them appear “dirty”.

CMYK Images
When incorporating photography or other CMYK illustrations into your design, please keep in mind that the image on your computer monitor or output devise displays may not match the color that will be achieved on press. All monitors and color printers are calibrated differently, and they do not represent the effects that dot gain may have on an image.

For all designs that include CMYK elements, we will produce a color match proof that will reflect the appearance which can be expected on press.  This proof will be submitted for approval prior to making printing plates.

We recommend that a proof be supplied, which represents the appearance that you would like to achieve, so that our prepress department can make any necessary adjustments to match it as closely as possible.  If you choose to do so, please clearly indicate that we are to match the supplied proof for color.

When placing Photoshop images into Illustrator files, please do not embed the images, place as a link to the external file and supply the CMYK Photoshop file separately. (We may need to adjust the image for flexo printing separately).

Trapping
Kopco Graphics utilizes an electronic on-press registration system to monitor and correct registration during the course of a press run, resulting in outstanding registration capabilities.  However, absolutely perfect registration is difficult to achieve on a flexographic press, therefore certain measures need to be taken to insure that the design is not negatively affected by slight mis-registration.

Trap refers to the slight overlap of elements in a design, which occurs wherever elements on different plates are adjacent to one another.  Trap prevents gaps from appearing in the print in the event of slight mis-registration on press. 

Kopco Graphics will set traps on your files as a part of our prepress process before making printing plates.  While we request that any files supplied to Kopco Graphics NOT be trapped, it is important to understand the concept of trapping and how it may affect the appearance of your design.

Text
• Positive Text
Minimum type size for positive text is 4 points.  Type below this point size may not be legible when printed.  With this in mind, please pay special attention to registered and trademark symbols.

For best results, small text should be created from one solid color.  Screened text can be difficult to read, and a slight mis-registration on press can affect the legibility of text that is created using more than one color.

• Reverse Text
Minimum type size for light-colored text that reverses out of a dark-colored background is 6 points.  Type below this point size may fill in and not be legible when printed.  We do not recommend using light-style fonts or serifed (?)fonts for reversed-out text, as the thinner portions of the letters will have a tendency to fill in.  Watch for any areas of text that are less than .01” in thickness – these may not reproduce well.  Type should never reverse out of more than one color.  Utilize a solid, single color keyline, (minimum thickness of .75 points, or .01”), to outline the light-colored text reversing out of a background that is built from more than one color.

Text should always be created in vector format.  Text created in Adobe Photoshop or any other raster-based program, will have jagged, rastered edges, making smaller text particularly difficult to read.  Vector based graphics and text will have smooth edges.

Dropshadows
Please be aware that the addition of a drop shadow to reverse text introduces an additional color to the background, meaning that the background color and the drop shadow color would have to be in perfect registration in order to create the shape of the letters properly.

For this reason, we discourage the use of drop shadows, particularly on small reverse text.  If a drop shadow is required, we recommend adding a gap between the light-colored text and the drop shadow on larger text or a single-color key line / drop shadow combination on smaller text so that the shapes of the letters themselves appear on only one plate.

Fonts vs. Outlines
While converting text to outlines eliminates the possibility of text reflowing or fonts not viewing or reproducing properly, it limits our ability to edit or resize text in the event that revisions need to be made to content or layout of the text.  Should text revisions be necessary, we may not be able to duplicate the appearance of the copy if we cannot identify or do not have the font that was originally used.

For best results, we recommend that two versions of the file be supplied, one with text converted to outlines and one with live text.

UPC Bar Codes
Bar codes should be no smaller than 85% and no larger than 120%. (see Upc code Guidelines)

Make sure that the bar code prints in a scan-able color. Since most bar code scanners utilize infrared light, avoid using inks with red or orange pigments.  If you have questions about the scan-ability of a certain color, please contact Kopco Graphics’ graphics department. 

For best results, we recommend that bar codes be printed in 100% black and appear on a white background. 

Make sure to allow a “quiet zone”, or no-print area of at least 1/8” to left and right of the leftmost and rightmost bars of the code.

In order to avoid potential distortion, the code must be placed so that the bars run through the press in the same direction that the film runs through the press. If you have a question about the press direction, please contact our graphics department.

File Format and Transfer
Adobe InDesign and Quark XPress file are also acceptable, however, please be advised that they may be exported for use with Adobe Illustrator.  The programs are excellent for typesetting and building multiple page documents, however, they are not ideal for package design.

IMPORTANT: Support files must be supplied for all images, including those that are embedded.

Photoshop files should be 300 dpi at the size at which they are placed into the final file.  Please keep in mind that the resolutions of a raster file decreases proportionally when enlarged. For instance, if a 2” x 2” image that is 300 dpi is placed into a file at 200%, the resulting dpi is 150, which is not high enough to reproduce well.

When supplying Photoshop support files, please do not compress the layers in the file; please submit files in CMYK format.

Please supply the fonts for any live text that appears in the file.  Any fonts that are not compatible with a Macintosh platform must be converted to outlines.  (Please be aware, however, that converting text to outlines limits the ability to make any content or layout adjustments.)

Always include either a PDF or a hard copy proof for your final file so that we may verify that the file we have received is correct and that there are no issues with fonts or special effects.  If you have a color target that you would like for us to match for a CMYK illustration, please send it to your Kopco Graphics’ Sales or Customer Service representative.  If you do so, please make sure that the proof is clearly labeled as a color target.

You may transfer files by email, uploading them here or on a CD or DVD.

Quick Reference Guide
Maximum number of colors: 10 (including white and varnish if applicable)
Line Screen: 85 lpi – 175 lpi
Trap Size: .007” - .02”
Minimum type size (positive text): 4 points
Minimum type size (reverse text): 6 points
Minimum rule size (positive): .25 points
Minimum rule size (negative): .75 points
Bar Code Size: 85% - 120%

Additional Resources:

To establish new bar code numbers:
GSI (formerly the Uniform Code Council): www.uc-council.org

FDA Food Labeling Guide:
www.cfsan.fda.gov

USDA Meat and Poultry Labeling Guide:
www.fsis.usda.gov

Kopco Graphics, Inc. serves many different industries, each with their own complex labeling requirements.  It is our customers’ responsibility to verify that their packaging meets any requirements set forth by regulatory agencies governing their industry.

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