Flexographic printing is a type of printing that involves the use of plates and presses. It is used for printing on various materials like paper, cellophane, metallic films and plastic. This mode of printing is used to produce artwork of HD quality. Flexographic printing is a technical form of printing. This type of printing prints at a high-speed and is suitable for label and packaging applications. It is suitable for high quality label, cost efficient and faster printing for your print on demand business.
How flexographic printing works?
The material, a roll-like material go through various plants that are rotary and flexible. There is a specialised roller that adds ink on each roller. The relief plates operate together to give colours for the print product. Flexographic printing can join with printing to increase capabilities and production speed. Sometimes this requires die-cutting, embossing and laminating. Flexographic printing is used to print substrates like multilayered film composites, metallic surfaces, non woven fabric, corrugated cardboard, plastic film and paper. Its flexibility caused the use of products like plastic bags, food packaging, stack & cut and self-adhesive labels. This led to speed advantages, efficiency and development more than the rest of the printing methods.
Ultraviolet Flexography
Ultraviolet flexography makes use of inks which are curable and not the standard drying methods for solvent-based inks or water. You can dry inks faster than others, cutting down time of production. There are various benefits with this curative ink like simple to use, dries faster, dries only under ultraviolet making the printer ready, superior quality for various applications, volatile organic compound (VOC).
Types of rollers for flexographic press
There are 4 types of rollers for flexographic plates, they are:
i) Fountain roller
ii) Anilox roller
iii) Plate cylinder
iv) impression cylinder
The fountain roller moves ink from a ceramic ink-metering anilox roller. This is from an ink after which it moves to the plate cylinder, the ink applies to its substrate. Pressure moves from the impression cylinder which is the pressure necessary for transmission of ink from a plate to its substrate. The anilox roller transfers ink to a printing plate that is flexible. There are finely engraved cells on each anilox roller with a particular ink capacity. There could be a doctor blade, an optional scraping blade for the surface of the anilox roller to make sure the delivery of the ink is from the ink inside the engraved cells.
When the substrate passes through the press, another coating or colour is added to the deck. Drying units are used to ensure that there is complete drying of the ink colour. Dryers can use ultra violet light, infrared or hot air, based on an application.
Printing presses
- Stack press involves stacking the decks vertically. You can print on each sides of the material as it moves through a press.
Central Impression (CI) press are across a large and single cylinder. These presses give an excellent registration.
In-line press has a positioning of the printing decks linearly to enable heavier substrates to be handled like corrugated boards.
Narrow-web presses are smaller or 10 inches wide since they are made for printing labels. Today you can use this type of presses for shorter runs including pouches, smaller packets and bottle wraps.
