UV Printers and UV Ink (Global Market)

Configuration

There are three main configurations of widescreen UV printers. The configuration has a significant influence on the accuracy of the image placement relative to the material, and also determines the speed of circulation production.

UV Printers for Roll Media

The supply of material in these types of machines is carried out using pressure rollers in the same way as in all inkjet printers. This configuration is used mainly for printing on soft (roll) media, which includes banner PVC fabrics, canvas, self-adhesive films, nets. The purchase of such a printer is justified when focusing the printing production only on rolled materials.

Conveyor UV Printers

This configuration of UV printers is the most functional and therefore in demand. It allows you to print both on roll media and on most rigid (sheet) materials. The conveyor is a mesh belt stretched between two shafts. A vacuum clamp system is used to fix the material. As a rule, such machines are equipped with a system for feeding-receiving (wrapping) roll materials. Application of this type of configuration is particularly effective in circulation industries where the minimum time to feed and take off material is an important factor. When printing on rigid materials, in the event of increased requirements for the accuracy of the image and the edges of the medium, deviations in the supply of material are possible, and the longer the product, the greater the displacement. This disadvantage is due to the uneven tension of the conveyor belt and the material it consists of. This disadvantage can be minimized only by the machine operator, who knows the experience and skill necessary for this.

Tablet UV Printers

This configuration implies a fixed horizontal table. All main movements are made by the portal (superstructure with carriage). The material is fixed to the table by means of a vacuum pressing system or by means of a double-sided adhesive tape for temporary fixation. Such machines are recommended for printing industries focused on products made of rigid (sheet) materials, including plastic, glass, metal and wood. The possibility of printing on roll materials is provided only on some models of tablet printers by including additional components (options) in the configuration, which leads to an increase in the cost of the machine. Technologically, plate UV printers are a preferred solution over the conveyor configuration due to the presence of a fixed table: the possibility of material displacement, regardless of its weight, is avoided, and, as a result, more accurate application of paint to the surface relative to the edges of the material is ensured, which is not always possible with the conveyor belt.

UF-ink

In aqueous and solvent-based inks, 50% to 70% of the volume is occupied by substances that evaporate from the surface after application. In contrast, UV ink is a polymer that, when printed, is almost 100% transferred to the surface and does not evaporate anywhere. UV inks, despite their higher cost relative to other types of inks, are used up to twice as efficiently.

UV curable inks typically consist of the following components:

• photoinitiators;
• oligomers;
• monomers;
• dyes;
• special additives.

Photoinitiators.

During UV curing, photoinitiators are the main components. After absorbing ultraviolet light from a source located in the printing carriage, the photoinitiators penetrate the reactants that trigger the chemical polymerization reaction (the reaction of combining individual molecules into long molecular chains). This process converts the liquid ink into a solid film.

Oligomers.

These substances determine the final properties of the cured film, including elasticity, resistance to atmospheric and chemical influences. Oligomers have a high molecular weight and are a kind of chemical framework of UV ink.

Monomers.

A monomer is a single molecule that can become chemically bound to other monomers to form a polymer. Monomers are present in the ink composition to give them special properties, increase the hardness and abrasion resistance of the film, but can also increase the viscosity of the chemical compound.

Dyes.

In UV ink, dyes based on paints or pigments are used. Typically, dyes are based on pigments because of their high retroreflective power and durability compared to paints.

Special additives.

Depending on the formula of the UV ink, flow forming and thinning agents, antioxidants and stabilizers may be included. To ensure uniform coating of the material, special surfactants are added to the ink composition. It is very important to control the spraying process, which affects the correct formation of the point and is important to ensure high image quality.

Stabilizers affect the shelf life of the ink and the resistance of the composition to heat, which is important at high injection temperatures. The stabilizers neutralize or absorb reactive molecules in the ink during storage and prevent their premature polymerization. Graphic diagrams of the process of curing the UV ink are shown below.

Under the influence of UV radiation from the source, photoinitiators activate the polymerization reaction - intermolecular bonds are formed.

The polymerization process continues for some time after the radiation exposure has ceased. After all the components are included in the reaction, the ink is completely polymerized. The speed of curing is greatly influenced by the power of ultraviolet radiation. The higher it is, the faster the reaction proceeds.

After the completion of the chemical reaction, a film is formed with strong molecular bonds and spent photoinitiators in the structure.

Paint curing system

One of the most important components of a UV printer is an ink curing system. Since the beginning of the first UV devices, powerful ultraviolet lamps have been the only means of curing the ink. Relatively recently, full-fledged UV printers have appeared using UV-LEDs that emit ultraviolet light.

UV lamps.

Such radiation sources are mounted on the printing carriage of the printer. An aluminum reflector and a powerful cooling system are installed on the back side of the printed field to the lamp. In most printer models, the material is protected from radiation during the reverse travel of the carriage by special curtains, which open and close automatically depending on the selected printing modes.

The use of UV lamps implies the obligatory presence of a lamp cooling system in the printer, and for printing on temperature-sensitive materials, the presence of a material cooling system after irradiation.

The disadvantages of this type of ultraviolet light sources are the release of a large amount of heat during the operation of lamps, high energy consumption, relatively short lamp life (from 600 to 1500 hours). Despite this, it is UV lamps that are installed in more than 95% of all UV printing equipment. To the relatively short life of lamps, another drawback is added: the unreliability of the lamp cooling system. As a rule, in most design solutions, an air cooling system is installed in UV printers. When operating the equipment in conditions that differ from those recommended by the manufacturing plant, a quick failure of cooling fans is possible. To avoid such equipment failures, it is necessary to regularly prevent the printer cooling systems and comply with the operating conditions according to the technical data sheet of the machine.

UV LEDs.

From the very beginning of the creation of UV printers, manufacturers tried to find an alternative to UV lamps. The only option at the time was ultraviolet emitting diodes, but the difficulty was that the LEDs then had very low power (measured in milliwatts) and high cost. But the LED industry is developing at a fairly fast pace, and today there are already full-fledged printers that use LED sources of ultraviolet radiation. The advantages of this technical solution are many: high efficiency of LED strips, lack of strong heating of the material, low power consumption and turning on LEDs in milliseconds. During the time that the life of the LEDs is estimated, when working with a printer on two UV lamps (for bidirectional printing), you will have to replace each lamp more than 40 times.

Currently, the difficulty in operating UV printers on LEDs is associated not so much with diodes due to their insufficient radiation power, but with the need for a special chemical composition of UV ink and the lack of a sufficient number of paint suppliers. Therefore, when buying an LED UV printer, it is necessary to seriously take the choice of a supplier of consumables. So, it is quite possible that at a certain and most crucial moment the user may be without consumables for his machine.

Undoubtedly, LEDs have proven the advantage of their technology in all respects, but the main criterion for many manufacturers of commercial graphics is the criterion of the economic feasibility of using a particular technology for their printing production.

Ink Supply System

The ink supply system is designed for uninterrupted ink supply to the printheads. The main components of the system are: ink storage tanks, superchargers (pumps), a white recirculation system, reverse pressure pumps (not in all printer models), subtanks (ink containers in front of print heads) and print heads. Let's look separately at the main nodes of this system.

Tanks

Containers for UV ink are made of opaque material. This is due to the property of the ink to solidify under the influence of ultraviolet light. The intensity of sunlight is not enough to quickly cure the ink, but over a long period of time this effect can affect the properties of the paint. For the same reasons, all UV printer tubes through which the paint flows are made of black material.

Superchargers

To supply ink from the main containers to the printing carriage, special ink pumps for each of the colors are used, which work depending on the readings of the sensors in the containers on the printing carriage (subtanks).

White recirculation system

For white, modern UV printers have a special paint recycling system. This is due to the property of white paint with long-term idle in containers to delaminate into components. The recirculation system ensures a uniform ink composition throughout the operation of the printer. The container with white paint is also equipped with a supercharger, like the main colors, for supplying paint to the subtanks.

Negative pressure system

When the printing mode is turned off, the ink should not flow out of the nozzles of the printing heads. To do this, you need to create a reverse pressure in the subtanks. At the moment, there are two ways to adjust the reverse pressure: adjust the position of the subtank and force the creation of reverse pressure. These ways have their advantages and disadvantages. Let's dwell on them in more detail. The position of the subtank is adjusted by changing the vertical position of the subtank relative to the printhead, thereby creating a back pressure. This design is cheaper and has no additional components. The main disadvantage of this method is the difficulty of pressure control under unstable and changing conditions. There is a possibility of ink failure to print heads at high print speeds.

Pressure adjustment with a pump implies the presence of a separate system that creates a negative pressure in the subtanks. The main advantage of such a system is the ease of control under various operating conditions. In addition, in this case, the ink is continuously supplied to the subtanks at high printing speeds.

Printhead

UV print heads are not fundamentally different from the heads used in modern printers using solvent-based inks (solvent and eco-solvent inks). Therefore, it is possible to consider the characteristics of the heads in general.

The most important characteristics of print heads are the speed and print quality they provide. I want to draw your attention to the word "quality": this is a concept that we can all interpret in different ways, and each has the concept of quality individually. In its direct definition, it sounds like this: "Quality is the correspondence of the actually obtained values ​ ​ (characteristics, detail, etc.) with the preset value." Therefore, I propose not to use this concept, but to replace it with specific descriptive characteristics - for example, high detail or uniform filling.

Print speed

So let's consider what affects print speed? Firstly, the speed of the printhead or the clock speed of the piezoelectric elements spraying the ink from the nozzles. The higher the clock speed, the more dots the printhead will be able to put per unit length at the same speed of movement of the printhead. Accordingly, heads with a high print frequency require the use of more high-tech service electronics, which significantly affects the increase in their cost. The number of print heads per ink multiplies the fast printing capabilities. So, when installing two heads on each color, we get twice as large a sealing area in one passage of the carriage.

When installing three or more print heads on one color, the result will be even higher, but there is one important nuance - pre-adjustment of the machine, or "mixing heads." When purchasing equipment with multiple print heads of the same color, you need to pay attention to the training of your operators by the service engineer of the supplier company, otherwise the installation and configuration of the equipment will take a lot of time and effort. It is easy to bring two or three print heads together, but it is already quite difficult to configure the operation of more than four heads. Mixing is necessary to correctly position the print heads of the same color between each other and three or more more groups of print heads of other colors. If you set up incorrectly, you will see "lashes" of colors within one print pass.

Existing high-frequency heads in a single color combination are capable of printing speeds up to 140 square meters per hour for outdoor use and up to 70 square meters per hour for printing in interior quality mode.

Image Detail (Print Quality)

The following characteristics of print heads are responsible for high image detail, smoothness of color transitions: drop size (in picoliters) and the number of print dies per unit length. High-speed outdoor printing machines use print heads with a drop size of 80 pl to 40 pl. With a high printing speed, this droplet size ensures saturation and uniformity of filling of uniform colors (spot fills). Large droplets, not having time to absorb into the material, spread, merging with neighboring droplets, which leads to the provision of more uniform colors without grain. Heads with a drop size of less than 40 pl are more suitable for interior image quality, where smooth color transitions and high detail are needed.

Above we have discussed certain values for the size of the printhead drop. Many heads are characterized by a fixed droplet size. By purchasing a printhead with a large drop, we deprive ourselves of the interior quality of the image and, conversely, by purchasing a head with a small drop, we lose the speed of printing advertising for outdoor use. For situations where you need to combine high speed printing of outdoor advertising and high detail of interior images in one printing press, the use of print heads with a dynamic drop (with a technology for forming a drop of ink of variable volume) is not best suited. Dynamic drop heads allow you to change its size depending on the type of area being sealed. For example, if it is a uniform fill, a large droplet size is used, and, conversely, for color transitions, a smaller droplet size is used. An example of static drop and dynamic printing is shown in the figures below.

Another characteristic of the printhead responsible for image detail is the physical resolution of the printhead, or number of printhead dies per unit length (1 inch). Duces are very small holes in the printhead through which the piezoelement sprays ink. The larger the nozzle, the greater the number of drops the printhead can apply to the surface in one pass, and the more tightly the drops will lie in relation to each other, ensuring uniform filling. There are several configurations for the arrangement of printed foils: single-row, double-row, staggered arrangement and rotation of the print head with a single-row arrangement of foils by a certain angle, which increases the density of drops, but reduces the size of the printed field in one pass of the head.

Paint heating

Some printheads are provided with an ink preheating system prior to surface injection. Such a technical solution is due to the properties of paints and the need for their preliminary preparation to ensure uniform application. There are heads with a single heating system for all heads of the printed carriage, where a single temperature is set for all subtanks, as well as heads with individual heating for each subtank. Do not forget that the paint of any shade uses chemical dyes, which in turn are various chemicals and affect the properties of the entire paint. Controlling the temperature of the ink separately for each subtank allows you to achieve a finer setting for each color, which is especially important in UV printers.

Major manufacturers

• Oce
• Fujifilm
• Inca
• Epson
• Mimaki
• Sigmajet
• Keundo

Global market

2023: Global UV Printer Market Size Up 10% to $2.17 Billion for the Year

In 2023, sales of UV printers on a global scale amounted to about $2.17 billion. The indicator of the previous year, when costs in this area were estimated at $1.98 billion, was exceeded by 10%. This is stated in the Market Research Future study, the results of which were published at the end of December 2024.

One of the main drivers of the industry in question, analysts call the growing demand for environmentally friendly solutions. UV printing technology provides instant curing of the ink, which reduces the amount of volatile organic compounds and harmful emissions associated with traditional printing methods. In addition, UV printers consume less power and generate less heat compared to other types of devices. These qualities not only benefit the environment, but also ensure compliance with the strict requirements for industrial production processes.

UV printers can work with any type of media, including wood, plywood, leather, metal, glass, cardboard, plastic and many other materials. In addition, such equipment ensures the durability of prints and their high quality. It is possible to print on colored, dark and transparent products without color distortion and loss of brightness. Moreover, products with the applied image can be operated immediately after printing. Thanks to these characteristics, UV printers are in demand in a variety of areas - from outdoor advertising and the production industry to interior design and souvenir making.

Technological advances also have a stimulating effect on the industry. Developers are constantly expanding the functionality of the equipment, increasing the speed and quality of printing, which makes UV printers more attractive to business. More and more brands are realizing the importance of packaging and creating marketing materials to attract consumer attention - UV printing devices allow them to effectively solve such problems.

The study authors identify four key industry segments: packaging printing, fabric printing, signage printing, and industrial printing. In 2023, these areas provided revenue in the amount of $0.87 billion, $0.54 billion, $0.45 billion and $0.31 billion, respectively. Significant players in the industry are named:

• Brother;
• Xerox;
• Mutoh;
• Videojet Technologies;
• Durst Group;
• Canon;
• JHF Technology;
• Kyocera;
• Inca Digital;
• Agfa Graphics;
• Mimaki Engineering;
• Roland DG;
• Epson;
• HP;
• Seiko Instruments.

Geographically, North America became the leader in 2023 with expenses of about $0.95 billion: the dominance of the region is due to the rapid introduction of advanced technologies and high demand for UV printers in various industries. In second place is located Europe with costs at the level of $0.6 billion. The Asia-Pacific region closes the top three, estimated at $0.4 billion. The contribution of South America amounted to approximately $0.1 billion, while the Middle East Africa brought in approximately $0.07 billion.

Analysts believe that in the future the industry will maintain a steady positive trend. However, issues such as significant upfront equipment setup costs and high levels of competition could hinder faster market expansion. At the end of 2024, revenue in the UV printer segment is estimated at $2.38 billion. Market Research Future analysts believe that in the future, the CAGR will be 9.7%. As a result, by 2032, costs on a global scale could increase to $5 billion.^[1]

According to Rusnano, the global UV printer market in 2008 amounted to 2,766 units (growth forecast by 2013 - 85%) and $607 million (growth by 2013 - 63%).

In turn, the UV ink market in 2008 reached 1,638 thousand liters (growth forecast by 2013 - 117%) and $248 million (growth by 2013 - 64%).

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