UV cured liquid coatings can be applied in a variety of finishes and looks, including Gloss, Matte, Raised, Reticulated, Pearl, Glitter, and more. These can be combined for dynamic effects, and can also be used with several of our laminating films. Liquid UV coating polymerizes to become a hard plastic layer, providing a durable finish for your printed product.

Use UV Coatings to:

• Achieve very high gloss or dull matte finishes
• Accentuate graphics and design
• Protect soft print surfaces
• Limit fingerprinting with Matte UV
• Add textures to the finished surface
• Make your printing pop

Design and Production Notes

Design

• Our variety of looks and finishes, with precise registration, allows you to match our coatings to your graphics, to create unique branding effects.
• UV coatings over unprinted areas create monochromatic images as the reflectivity is heightened or diminished.
• Create logos or wallpaper effects.
• Use spot images to visually balance bold graphics.
• Raised and textured UV coatings can provide tactile appeal.
• Raised and flat, or gloss and matte coatings can be used together.
• Fingerprints may be more noticable on Gloss UV when applied over darker colors.
• For more tips, and to discuss your ideas, please contact one of our knowledgeable staff at 714-828-7890.

Image Size

As our spot UV coating is applied by the silkscreen process, gradient and fine line images can be unpredictable in how well they will reproduce. We suggest 10 pt as the absolute minimum image size. Slightly larger tends to work a little better. The height of raised UV on line art images will vary with line thickness.

Paper

UV Coatings are designed for coated papers only. Sheets with good ink hold-out should be selected. Cast coated or uncoated papers tend to absord the liquid coating before it can cure, producing a mottled or stained look. We recommend acid-free papers to prevent yellowing.

Optimum stock thickness for UV coating is .007” and up, especially if it requires folding. Lightweight stocks can tend to curl up and may crack when folded.

Ink

Inks must be dry, and free of paraffin waxes, silicones, or other slip additives, to allow proper adhesion of the UV coating to the substrate. Inks should be sufficiently heat resistant to avoid softening during the curing process.

Alkaline pigments such as those found in Reflex Blue, Rhodamine Red, PMS Purple, and similar colors should be avoided as they can react unfavorably with UV cured coatings. Please contact your ink supplier for the availablity of alternate pigments.

Metallic inks must be fully dry before coating. As these inks can take longer to dry than standard inks, care should be used when sealing these inks with AQ coatings. This can increase drying time substantially.

Please note that aqueous coatings can increase the drying time of inks, as they limit the ink’s access to air. UV cured coatings may bond to the aqueous coating, only to have the inks separate underneath, resulting in a poor overall bond of coating to ink to paper. Extra moisture in the paper, inks, or coatings can vaporize during the curing process, resulting in pinholes in the finished surface.

Digital Printing

Most digital inks can be UV coated. Please allow the manufacturer’s recommended time for the fuser oils to fully absorb into the paper. Not all digital printing responds the same to UV coating. If you have not UV coated after printing from your digital press, we suggest testing before committing to production. Generally speaking, higher ink densities have a greater likelihood of rejecting UV coatings. Please let us know when a job is to be digitally printed.

Spot UV Images

Please supply your desired UV image as a 100% black PDF positive, fully imposed to the press sheet. You can also supply film, again, 100% black, RRED, fully imposed. Proofs or rule-outs supplied with jobs can help to avoid errors in position.

Spray Powder

Spray powder remaining on the paper before UV coating will appear after UV coating. The larger the particle size, and the more powder used, the more speckled or “sandpaper” the finished result will be. We recommend using the smallest particle size possible (e.g. 30-50 micron), and dusting or polished the printed sheets to remove the spray powder before UV coating.

Converting and Finishing

Scoring, cutting, and folding are performed after UV coating. Scoring and folding with the paper grain will greatly enhance the UV coated paper to fold without cracking. Foil stamping can be done before or after UV coating, with the following considerations. For foil stamping before UV coating, specify UV coating compatible foils. Any extraneous foil must be removed from the paper prior to UV coating. For foiling after UV coating, we will need to knock out the foil area, as foil will not adhere to UV coating.

Special Considerations for Raised and Textured UV Coating

When designing materials that will receive Raised or Textured UV coatings, please allow a minimum of 1/16” from the edge of the coating area to scores, cuts, and folds. Due to their thickness, these UV coatings can have a tendency to crack when subjected to these processes.

Special Considerations for Multiple Process Coatings

Multiple passes of UV coatings, such a spot gloss with a spot matte UV, may cause paper to dry or become brittle, due to the energy of the UV curing process. Care should be taken to match paper grain direction to folds, and to specify papers with good folding characteristics, to minimize any cracking during the finishing process.

This can be addressed with the use of film lamination, which provides a flexible, protective surface to the printed piece. Certain laminating films are coatable and printable. Please inquire for additional information and design considerations.

Submitting Your Order

For UV coating, supply untrimmed press sheets. Include a rule-up sheet with Gripper and Side Guide marked. Clearly label the side that is to be coated. Please note, if you print with excessive white space, you can pre-trim your sheets for a smaller coating size, however, you will need to preserve the Gripper and Side Guide on spot UV runs, so that we can maintain registration to your image.

For overall UV coating, we require a minimum of 1/2” gripper, 1/8” sides, and 1/4” tail outside of your required image. Please inquire concerning image areas larger than this.