Flexography (often abbreviated to flexo) is a form of relief printing and is the method of printing most commonly used for packaging (labels, tape, bags, boxes, banners, etc.).

A flexographic print is made by creating a positive mirrored master of the required image as a 3D relief in a rubber or polymer material. A measured amount of ink is deposited upon the surface of the printing plate (or printing cylinder) using an engraved anilox roll whose texture holds a specific amount of ink. The print surface then rotates, contacting the print material which transfers the ink.

One method of plate development uses light-sensitive polymer. A film negative is placed over the plate, which is exposed to ultra-violet light. The polymer hardens where light passes through the film. The remaining polymer has the consistency of chewed gum. It is washed away in a tank of either water or solvent. Brushes scrub the plate to facilitate the "washout" process. This method is considered "old-fashioned," but is still widely used in smaller operations, and is still taught in most high school and college flexo programs.

Originally flexographic printing was basic in quality. Labels requiring high quality have generally been printed using the offset process until recently. In the last few years great advances have been made to the quality of flexographic printing presses.

The greatest advances in flexographic printing have been in the area of photopolymer printing plates, including improvements to the plate material and the method of plate creation, usually photographic exposure followed by chemical etching, though also by direct laser engraving.

Digital direct to plate systems have dominated the industry recently with their better resolution and the ability to print four color process (or more) as well as offset. Companies like Dupont, MacDermid, Kodak and Esko have pioneered the latest technologies with advances in FAST washout and the latest screening technology, even companies who make plates in house are going to trade shops to get these high quality plates.

Laser-etched anilox rolls also play a part in the improvement of print quality. Full color picture printing is now possible, and some of the finer presses available today, in combination with a skilled operator, allow quality that rivals the lithographic process. One ongoing improvement has been the increasing ability to reproduce highlight tonal values, thereby providing a workaround for the very high dot gain associated with flexographic printing.

Flexo has an advantage over lithography in that it can use a wider range of inks, water based rather than oil based inks, and is good at printing on a variety of different materials. Flexographic inks, like those used in gravure and unlike those used in lithography, generally have a low viscosity. This enables faster drying and, as a result, faster production, which results in lower costs.

Printing press speeds of up to 600 meters per minute (2000 feet per minute) are achieveable now with modern technology high-end printers, like Flexotecnica [1], which introduced the world's first 12-color central impression (CI) drum press at Drupa 2008. Other press formats, such as in-line and stack presses, are available from Tresu and other suppliers.

Contact sales@logmatix.com or call 1-800-527-2498 for all your Flexo needs!

Logmatix Labels & Tags also specializes in Variable-data printing. Let Logmatix Labels & Tags handle all your concert, sport or general ticketing needs. Variable-data printing (VDP) (also known as variable-information printing (VIP) or VI) is a form of on-demand printing in which elements such as text, graphics and images may be changed from one printed piece to the next, without stopping or slowing down the printing process and using information from a database or external file. For example, a set of personalized letters, each with the same basic layout, can be printed with a different name and address on each letter. Variable data printing is mainly used for direct marketing, customer relationship management, advertising and invoicing on selfmailers, brochures or postcard campaigns.

The technique is a direct outgrowth of digital printing, which harnesses computer databases and digital print devices and highly effective software to create high-quality, full color documents, with a look and feel comparable to conventional offset printing.

Variable data printing enables the mass customization of documents via digital print technology, as opposed to the 'mass-production' of a single document using offset lithography. Instead of producing 10,000 copies of a single document, delivering a single message to 10,000 customers, variable data printing could print 10,000 unique documents with customized messages for each customer.

There are two main operational modes to VDP. In one methodology, the document template and the variable information are both sent to Raster Image Processor (RIP) which combines the two to produce each unique document. The other methodology is to combine the static and variable elements prior to printing, using specialized VDP software applications. These applications produce an optimized print stream, such as PostScript and PPML, which organize the print stream efficiently so that the static elements are only processed once by the RIP.

There are several levels of variable printing. The most basic level involves changing the salutation or name on each copy. More complicated variable data printing uses 'versioning', where there may be differing amounts of customization for different markets, with text and images changing for groups of addresses based upon which segment of the market is being addressed. Finally there is full variability printing, where the text and images can be altered for each individual address. All three types of variable data printing begin with a basic design that indicates which sections can be altered and a database of information that fills in the changeable fields. Since 2005, the term TransPromo or transpromotional has emerged to cover the merging of promotional content and transactional print pieces by involving more business users in the printing process.

The returns for variable printing vary from double the normal return at the basic level to 10-15 times the return for fully variable jobs. This naturally depends on content and the relevancy of that content, but the technique presents an effective tool for increasing ROI on marketing campaigns.