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What is the Difference Between These Three Print Heads?

May. 24, 2021

On the surface, it is a question of print head selection. In-depth understanding is actually an application problem for different inks and different market needs. To better improve the consistency and coordination with boards, inks, and media, this should be the original intention of Epson I3200 series print heads divided into water-based, UV, eco-solvent and other different types, with targeted subdivision.

Water-based is easier to understand. I don’t think anyone would want to use water-based print heads for UV and eco-solvent (oil-based) solutions. It is almost impossible to get high viscosity and low sheet UV inks through water-based print heads and obtain good control. At the same time, the life of the print head must be considered in this process. We will not discuss unconventional thinking too much. Because that road has been verified by history: this road is nowhere. Then Uv Ink Manufacturer will focus on the difference between UV print head and oil-based eco-solvent print head.

Uv Ink

About UV ink and eco-solvent ink:

1. Physical and chemical structure stability:

To understand this proposition, let us first understand the basic formula of each ink:

The composition of UV ink is much more complicated. Under the same conditions, UV inks are more likely to produce changes in physical and chemical properties.

2. Viscosity:

Both inks have a relatively wide range of viscosity, generally 4-20 centiples; but conventionally, UV is much larger than weak solvents in terms of solid content. Therefore, under normal circumstances, the viscosity of UV ink should be greater than that of weak solvent ink. Of course, the viscosity will be greatly affected by temperature. We will not go into more details about the viscosity. Normally, it is enough that the viscosity of the UV ink is greater than that of the weak solvent.

3. Surface tension:

According to the information provided by relevant experts, both have a relatively large range of options in terms of surface tension. The range is approximate: 22~35 dyne. The specific choice depends on the print head.

4. Corrosion:

For both types of inks, there is a certain degree of corrosiveness, but the degree of corrosiveness has not been investigated so far. It will also depend on the choice of each manufacturer's formula.

5. Temperature viscosity curve

Using a UV print head to print eco-solvent inks has no problem with fluency, but flying ink will appear and the shape of ink droplets will change. This will cause the amount of ink to pass through and the accuracy will be affected. This will bring about a series of problems such as adjusting the waveform and reducing the viscosity. This must be a test for the performance and stability of the UV print head. For equipment manufacturers, spending more time and energy to re-complete the technical update is also a kind of approach for equipment manufacturers.

The two print heads are mostly the same, with the same quality, the same accuracy, and the same ignition frequency. There are two differences:

1. The ink droplet size has a slight difference between single dots and multiple dots. UV ink droplets are about 1 pl smaller than weak solvent ink droplets. But whether this difference is eliminated or magnified when we cooperate with the ink, board, and ink circuit system, depends on the test situation in the actual cooperation;

2. Although the difference in viscosity value is not very large, there is no crossover part in the middle. The viscosity value of UV is 5~7 mPa·s, while the weak solvent is 3~4 mPa·s; for UV ink, it must be heated to about 45℃ to reach the viscosity characteristic of about 7 mPa·s, and it is dynamic; But the eco-solvent ink has a viscosity of about 4 mPa·s at about 25°C.

Our company also has Uv Ink on sale, welcome to contact us.