Digital printing is big business, with the total digital packaging printing market expected to reach nearly $36 billion by 2026[1], and many converters are looking to invest in a digital printing press.
Among the many considerations in finding the right press is the choice between two digital printing technologies: inkjet and electrophotography (toner).
With both options offering the well-known benefits of digital printing, this blog takes a closer look at both technologies, so you can make an informed decision about which press is best for your business.
What is digital inkjet printing?
Developed in the 1950s, commercial digital inkjet printing works in the same way as a desktop inkjet printer – on a larger scale – using a combination of software, hardware, and printing ink to reproduce digital images on a substrate.
As part of the process, the artwork is deconstructed into a pattern of dots, which is then recreated by printhead nozzles placing ink droplets onto the substrate.
Colour digital inkjet printing presses feature multiple arrays of printheads and nozzles that enable seamless print of designs by dispensing different coloured inks. Inks are composed of colour pigments suspended in a carrier liquid, which are blended together on the substrate to recreate a wide variety of different colours and tones. Colours installed are typically cyan, magenta, yellow, and black, with the option to add colours such as orange, violet, and white.
Ink droplet size is key to producing fine details, such as smooth gradients, microprint, and detailed Asian characters. Ink composition, viscosity, drop speed, and substrate absorption properties are all factors that affect ink laydown and colour blending.
In inkjet printing with UV inks, the inks are partially set in place by a pinning lamp during printing, and then cured to create a durable, high-quality finish.
What is toner printing?
Toner printing – also known as electrophotography – was first developed in 1938. The electrostatic printing technique powering office photocopiers and laser printers uses software, hardware, and dry or liquid toner to reproduce a digital image on a drum, which is then transferred to the substrate.
Liquid toner contains dyes or pigments and electrically charged particles encapsulated in resin. These are suspended in an oil-based carrier liquid, which evaporates in the fusing process. Dry toner is a powder that behaves like a liquid due to its small particle size. However, its particles are larger than those in liquid toner and demand higher fusing temperatures.
Electrically charged toner particles are drawn to these fields, creating single-colour images. In liquid toner printing, multiple single-colour images are transferred onto a heated belt, and the layers are fused into one multi-colour image, which is then transferred to the substrate. In dry toner printing, the single-colour images are often layered directly onto the substrate and fused by a heated roller.
The toner formulation, as well as the contact printing and fusing process mean that toner doesn’t penetrate the substrate to maximise adhesion. For that reason, toner labels often require varnish or lamination to ensure durability.
The limited bonding of toner with the substrate also means not all substrates are suitable for toner printing. Synthetic substrates, for example, require pre-treatment with primer to ensure toner adhesion. OEM-approved materials optimised for toner printing are available, often priced at a premium. Converters opting for digital printing with toner will usually do so as part of a lease from the manufacturer. In such models, each rotation of the imaging drums described above will incur a ‘click charge’, a flat rate to cover maintenance and consumable costs.
Performance: digital inkjet printing vs digital toner printing
Both inkjet and toner printing technology have their merits – and both deliver high print quality. In printing houses where both technologies are available, UV digital inkjet printing is often a preferred choice for converters. There are several reasons:
Colour consistency
Brand owners are looking for brand-compliant colour representation for their signature colours in all their labels.
Inkjet, a non-contact printing technology, is a great choice for print colour consistency. The technology tolerates fluctuating environmental factors, such as changes in temperature and humidity, without affecting print quality and consistency.
Toner print is far more susceptible to changes in temperature and humidity, which both can negatively affect the reliability of the static charge, impacting print colour consistency.
Print durability
Brands want labels that will look great throughout their products’ lifecycle, as well as maintain compliance, where expiry dates, allergens, or safety caution symbols are included.
A UV digital inkjet printing process delivers consistent curing of the ink, with good adhesion to a wide range of substrates used in the label market, creating a finish that offers long-term durability. After curing, UV inkjet labels are resistant to scuffing and scratching, offer good tolerance to environmental factors such as exposure to heat, water, and chemicals, and have high lightfastness – keeping colours vibrant and text legible throughout the product’s lifecycle.
This durability is achieved without additional coatings, such as varnish or lamination, typically needed with toner printing. Converters with access to both technologies can save money by opting for inkjet labels for more demanding applications.
Productivity
Productivity is one of the main criteria converters consider when comparing digital label presses, and inkjet typically wins when it comes to speed.
Both the inkjet and toner printing systems on the market today are capable of running at high speeds, however, digital inkjet printing technology holds the potential to run faster, as it doesn’t need physical contact to the substrate to produce an image. Most inkjet presses are able to increase printing speed by lowering the print resolution, with analysts predicting higher speeds maintaining high resolution will be possible as printhead technology progresses[1].
Speed improvements are more difficult to achieve for contact print with toner, as speed often depends on the toner particle size, coverage, and number of colours used – affecting the transfer speed and required fusing time. Here, multiple consecutive imaging engines are required to increase throughput. This expands the footprint of the press, increasing the initial investment and long-term running costs.
Textured finishes
A UPM Raflatac neuromarketing study suggests that consumers are drawn to labels featuring tactile finishes and embellishments. Both inkjet and toner printing systems are capable of elevating labels with textured finishes to respond to consumer preferences.
Digital inkjet printing technology equipped with high-opacity white ink can add textured effects to labels by printing a white pattern as a base layer that is then pinned and printed on as usual, creating a textured effect without the premium substrate.
Layering is also possible with toner, however, brand customers may not be prepared to pay the additional ‘click charges’ accrued by producing the layered effect.
In addition to producing textured effects easily, as a non-contact process inkjet is also suitable for print on uneven substrates, such as textured papers.
Cleaning & maintenance
Regular cleaning of any printing components is key to ensuring consistent print quality and avoiding unwanted transfer.
Cleaning and maintaining an inkjet press can be a breeze thanks to on-board tools that automate maintenance tasks such as nozzle cleaning and capping, and printhead alignment and registration. Cleaning and re-calibrating a toner press can be a more time-consuming affair, requiring a skilled operator.
Smithers’ The Future of Packaging to 2026 analysis reports typically lower uptime for converters using toner versus inkjet printing technology, affecting overall productivity and ROI.
Cost of ownership
Cost of ownership is another key consideration for converters, and consumables hold a large share of the regular running cost.
Converters having access to both technologies often use their toner press when producing labels with high coverage, as the ‘click charge’ remains the same, regardless of how much toner is applied, making toner the more economical option. For applications with average or low coverage, inkjet is often the preferred option, as ink cost is lower for these applications.
Smithers[1] has observed a trend of falling total cost of ownership in digital inkjet printing, thanks to high productivity and decreasing ink costs, which compare favourably to some of the ‘click charges’ typically associated with toner printing.
Conclusion
While both technologies have their merits, based on the comparison above, inkjet seems the better choice for a label converter looking to the future. But don’t take our word for it!
Domino is happy to welcome converters considering digital inkjet printing to our sample and demo facilities in the UK and USA, as well as the European Digital Centre of Excellence in the Netherlands.
Our experts can run customised demonstrations on the latest digital inkjet printing presses, using visitors’ sample files, so that converters can discover the advantages of inkjet printing, witness the ease of operation of the presses, and take a closer look at the excellent print quality of the inkjet label samples produced.
Find out more about the European Digital Centre of Excellence here.
[1] Smithers. The Future of Digital Print for Packaging to 2026. 2021