How to use offset UV dispersants
How to use offset UV dispersants
The use of offset UV dispersants mainly involves the selection of dispersants, the control of the amount of addition, and the details of the operation during the addition process. The following is a detailed answer to how to use offset UV dispersants:
1. Choose a suitable dispersant
Type selection:
The dispersants for UV offset inks are mainly inorganic, organic, and composite. According to the specific composition and requirements of the ink, you can choose a polymer dispersant, a polyester dispersant, or other suitable dispersant types.
Polymer dispersants (such as polyacrylates, polyurethanes, polyvinyl alcohol, etc.) are the most commonly used dispersants in UV offset inks, with good dispersibility and light resistance.
Inorganic dispersants (such as silicates, aluminum oxides, etc.) have good heat resistance and are often used in high-temperature resistant UV offset inks.
Performance requirements:
The dispersant should be able to evenly disperse the pigment in the ink, so that the ink has good fluidity and printability.
The dispersant should have good light resistance, be able to resist ultraviolet light, and prevent pigment precipitation.
For UV offset inks used to print high-temperature resistant materials such as plastics, a dispersant with good heat resistance should be selected.
2. Control the amount of addition
Addition range:
The amount of dispersant added should be determined according to the ink formula and the type and amount of pigment.
Generally speaking, the amount of dispersant added should be moderate. Too little will affect the fluidity, and too much may cause the ink performance to decline.
Experimental determination:
In actual production, the optimal amount of dispersant added can be determined by experiment.
By adjusting the amount of dispersant added, observe the changes in indicators such as ink fluidity, printability, and color vividness, so as to determine the optimal amount of addition.
3. Operation details during the addition process
Stirring evenly:
When adding the dispersant to the ink, ensure that it is stirred evenly so that the dispersant can fully play its role.
You can use stirring equipment or manual stirring, but the stirring speed and time should be moderate to avoid adverse effects on the ink performance.
Grinding operation:
During or after stirring, grinding operations can be performed to further refine the pigment particles and improve the dispersion effect.
Grinding time and grinding intensity should be determined according to the type of pigment and ink performance.
Viscosity adjustment:
If the viscosity of the ink is too high, you can use an oven to heat it to an appropriate temperature (such as around 60°C) to adjust the viscosity to improve the fluidity and printability of the ink.
However, care should be taken to avoid excessive temperature that may cause the ink performance to deteriorate or the dispersant to fail.
4. Precautions
Storage conditions:
The dispersant should be stored in a cool place at room temperature, avoiding direct sunlight and high temperature environments.
The storage period should follow the product instructions or relevant standards.
Safety:
When using dispersants, relevant safety operating procedures and protective measures should be followed.
Avoid direct contact of dispersants with skin, eyes, etc. If contact is made accidentally, rinse immediately with plenty of water and seek medical attention.
In summary
The use of offset UV dispersants requires the selection of appropriate dispersant types, control of the amount added, attention to the operating details during the addition process, and compliance with relevant storage and safety regulations. By using dispersants reasonably, the printability and color vividness of UV offset inks can be improved to meet the high quality requirements of printed products.