What Coating Means in Printing #
Coating is a finishing process in which a clear liquid layer is applied to the surface of printed sheets and then dried or cured. The purpose may be functional, aesthetic, or both.
Coatings can:
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Protect prints from scuffing and moisture
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Alter surface sheen
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Enhance colour contrast
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Add visual emphasis
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Improve durability for handling and mailing
Some coatings are applied uniformly across the entire sheet, while others — such as Spot UV — are applied selectively to highlight specific design elements.
What Spot UV Is #
Spot UV is a selective coating process in which a glossy, raised varnish is applied only to chosen areas of the artwork, such as logos, headlines, patterns, or images.
Unlike overall coatings, Spot UV creates contrast between matte and glossy surfaces and adds a tactile dimension to the print.
Spot UV is commonly used on:
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Business cards
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Folder covers
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Brochures
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Packaging sleeves
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Presentation materials
Because it involves a separate finishing stage and precise alignment, it is considered a premium enhancement rather than a standard protective coating.
Overall Coating vs Spot Coating #
Overall Coating #
An overall coating is applied uniformly across the entire printed sheet. Common purposes include:
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Protecting ink
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Reducing scuffing
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Adjusting sheen
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Speeding up drying
Examples include aqueous coating and full-sheet UV coating.
Spot Coating #
Spot coating is applied only to specific areas defined in the artwork file. Spot UV is the most common example.
Spot coating is primarily decorative rather than protective, though it can add limited surface resistance in treated areas.
Common Types of Print Coatings #
Aqueous Coating #
Aqueous coating is water-based and is often applied inline during printing.
Characteristics include:
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Low to medium gloss or matte finishes
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Quick drying
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Environmentally friendlier profile
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Light surface protection
It is widely used for flyers, brochures, and catalogues.
Full-Sheet UV Coating #
UV coating is cured using ultraviolet light and forms a harder surface layer.
It offers:
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Higher gloss than aqueous
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Stronger scuff resistance
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Enhanced colour depth
Full-sheet UV is typically applied when durability and visual impact are priorities.
Spot UV Coating #
Spot UV is applied through a separate screen or digital mask and cured selectively.
It creates:
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Raised texture
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High-gloss highlights
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Visual contrast
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Premium feel
Because it requires precise positioning, it involves more setup and cost than overall coatings.
How Spot UV Is Produced #
To apply Spot UV, printers use a dedicated mask layer that indicates exactly where the varnish should appear.
The typical workflow includes:
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Printing the base artwork
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Applying base lamination or coating (often matte)
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Registering the Spot UV mask
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Applying varnish selectively
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UV curing the coated areas
This multi-step process explains why Spot UV adds lead time and cost.
Artwork Setup Requirements #
Spot UV requires specific file preparation:
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A separate vector layer for the Spot UV areas
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Solid fills (usually 100%)
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Clear naming for the Spot UV layer
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No gradients unless approved
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Adequate clearance from trim edges
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Avoiding extremely fine details
Poorly prepared files are one of the most common causes of Spot UV production delays.
Design and Production Limitations #
Spot UV is subject to production tolerances. It is generally unsuitable for:
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Border-to-edge designs
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Very thin lines
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Small text
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Tight outlines
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Micro patterns
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Areas extremely close to trim edges
Designers should allow visual breathing room between coated and uncoated areas.
Cost and Turnaround Considerations #
Coating adds cost because it involves additional materials, equipment, and labour.
Spot UV is usually more expensive than overall coating because:
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Separate screens or digital masks are required
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Registration steps are added
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Curing stages are needed
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Extra quality control is performed
Jobs with Spot UV are often routed through RFQ when quantities are high or registration requirements are strict.
Choosing Between Coating Options #
Use overall coatings when:
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Basic protection is needed
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Faster turnaround is required
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Budgets are tight
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Uniform finish is acceptable
Use Spot UV when:
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You want to highlight specific elements
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A premium tactile effect is desired
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Contrast is part of the design
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The project is high visibility
Selecting the right approach early prevents redesign and re-quotation.
Summary #
Coating processes enhance both the appearance and durability of printed materials. Overall coatings such as aqueous and UV protect entire sheets and adjust sheen, while Spot UV selectively highlights chosen areas for visual and tactile impact.
Because Spot UV involves additional setup and precise alignment, it requires careful artwork preparation and realistic scheduling.
