WHICH INKS ARE USED IN LARGE FORMAT PRINTING?

• Using the bubble inkjet (thermal inkjet) and piezo inkjet printing technologies different printing materials are printed on with different inks.
  
  The following inks are used in large format printing:
  
    Water-based inks
    Solvent-based inks (solvent or eco-solvent)
    UV-curable inks
    Latex inks
    Dye-sub inks

 
The ink systems differ in size (printing width), quality and application due to their properties:

 WATERBASED INKS FOR PRINT MEDIA

Very high quality (in terms of color space and resolution) can be achieved with water-based ink systems – ideal for art reproduction, proofing and indoor applications in general as well as for closer viewing distances. However, water-based inks only bond with specially coated surfaces really well and are only suitable for outdoor use to a limited degree. In turn, the printers are easy to handle and in addition to machine shops are often also used in offices.

Printing widths: 61 cm to 152.4 cm

Principal use: Fine art, posters, indoor banners

Advantages of waterbased inks
+ Large color space
+ Simple processing, no health risk
+ Reasonably priced

Disadvantages of waterbased inks
– Low UV resistance
– Low water resistance (outdoor use is limited)
– Only print media with special coating

SOLVENT INKS FOR PRINT MEDIA

If prints need to be especially durable and are used outdoors, solvent or real-solvent inks, i.e. solvent-based, are used. These inks dissolve the substrate and bond with the print media, which means that solvent prints are very durable. The drying process is carried out with a heater (pre, main and post heating). However, a health risk is involved with solvent inks and they cannot be used in rooms without special ventilation equipment.

Printing widths: 137.2 cm to 500 cm

Principal use: Tarpaulins for outdoor use, car wrapping, signs

Advantages of solvent inks
+ Extremely durable (UV-resistant, water-resistant, scratch-resistant)
+ Suitable for outdoor use
+ High print speed
+ Low drying time

Disadvantages of solvent inks
– Relatively expensive printers
– Protective measures required when handling
– Can only be used with a ventilation system
– Inks are hazardous to health

ECO SOLVENT INKS FOR PRINT MEDIA

Eco-solvent or mild-solvent printers solve the emission problem in part: the inks are far less harmful to health and the environment but have similar drying properties and durability.

Printing widths: 75 cm to 260 cm

Principal use: Tarpaulins for outdoor use, car wrapping, wallpapers, flags, signs, stickers

Advantages of eco solvent inks
+ Very to extremely durable (UV-resistant, water-resistant, scratch-resistant)
+ Suitable for indoor and outdoor use
+ High print speed
+ Low drying time

Disadvantages of eco solvent inks
– harmful to health (less than real solvent)

UV-CURABLE INKS FOR PRINT MEDIA

UV printers are appropriate for any application which involves the printing of a variety of substrates (also uncoated). The inks are cured and fixed with a special UV light. Both flexible roll materials and single sheets, but also rigid print media and even glass can be printed on. Appropriate protective measures are needed when processing harmful UV inks.

Printing widths: 137.2 cm to 500 cm

Principal use: Flat plate printing (rigid materials), textiles (roll printing)

Advantages of UV-curable inks
+ Extremely durable (UV-resistant, water-resistant, scratch-resistant)
+ Suitable for outdoor use
+ Also on rigid and uncoated print media
+ No drying time

Disadvantages of UV-curable inks
– Protective measures are required when handling (gloves, etc.), otherwise harmful to health
– Inherent odor of the inks

LATEX INKS FOR PRINTING MEDIA

Water-based HP latex inks are still relatively new on the market. They are supposedly comparable with solvent inks in terms of quality and durability, but are less harmful to health and the environment. They do not contain real rubber, but consist of an aqueous polymer dispersion.

Printing widths: 51.4 to 264 cm

Principal use: Indoor and outdoor applications

Advantages of Latex inks
+ Simple processing, no health risk
+ Suitable for outdoor use
+ Very to extremely durable
+ No drying time

Disadvantages of Latex inks
– Limited choice of materials (because the ink must be fixed under heat)
– Only one printer manufacturer (HP)