Aqueous coatings have been in use by commercial packaging professionals for nearly three decades. As the demand for aqueous coatings grows, print technologies become more advanced. Three common print technologies are used to print aqueous coatings. They are flexographic, gravure and offset printing.

Aqueous coating vs. traditional overprint varnish:

• Good gloss
• Increased rub resistance
• Smoother feel
• Elimination or reduction of spray powder applications
• Faster handling of the printed products
• Decreased application time

The type of aqueous coating required depends heavily on the application. Below are three of the most common printing techniques for aqueous coatings.

Flexography

Flexography (often abbreviated to flexo) is a printing process which utilizes a flexible relief plate. It is essentially a modern version of letterpress which can be used for printing on almost any type of substrate, including plastic, metallic films, cellophane and paper. It is widely used for printing on the non-porous substrates required for various types of food packaging (it is also well suited for printing large areas of solid color).

Rotogravure

Rotogravure (roto or gravure for short) is a type of intaglio printing process, which involves engraving the image onto an image carrier. In gravure printing, the image is engraved onto a cylinder because, like offset and flexography, it uses a rotary printing press. It is often used for commercial printing of filmic substrates and other product packaging.

Offset

Offset printing is a commonly used technique in which the inked image is transferred (or “offset”) from a plate to a rubber blanket, then to the printing surface. When used in combination with the lithographic process, which is based on the repulsion of oil and water, the offset technique employs a flat (planographic) image carrier on which the image to be printed obtains ink from ink rollers, while the non-printing area attracts a water-based film (called “fountain solution”), keeping the non-printing areas ink-free. The modern “web” process feeds a large reel of paper through a large press machine in several parts, typically for several meters, which then prints continuously as the paper is fed through.

If you have questions about our custom formulated coatings, overprint varnishes, primers or print technology, please contact Roymal, Inc. for assistance at (603) 863-2410 or email roymal@roymalinc.com.