Is Water-based Ink Suitable for Screen Printing?
Date: Apr 02 2025 From: Star Color
The proportion of water-based ink in the printing industry is constantly increasing due to its unique environmental protection properties. So, can water-based ink be used in screen printing? As a widely used printing method, screen printing covers numerous fields, ranging from garment dyeing and printing to electronic product labeling. How does water-based ink perform in screen printing? Let's explore it from aspects such as environmental protection, adhesion, and drying.
I. Adaptation Foundation of Water-based Ink and Screen Printing
The principle of screen printing is to make the ink pass through the mesh holes of the graphic part and transfer onto the substrate through the extrusion of the squeegee, forming a graphic identical to the original. Water-based ink uses water as the solvent or dispersion medium. Compared with traditional solvent-based inks, it has the significant advantage of low volatile organic compounds (VOCs) emissions, which makes it highly consistent with the current development trend of the printing industry in terms of environmental protection.
In terms of the rheological properties of the ink, water-based ink has a moderate viscosity. If water-based ink is to be used in screen printing, a thickener is required.
| Performance Indicator |
Water-based Ink |
Solvent-based Ink |
Industry Requirement Standard |
| Viscosity (Pa·s) |
3-8 (with thickener needed) |
10-15 |
Textiles: 5-10; Plastics: 8-12 |
| Drying Time (25℃) |
15-30 minutes (natural drying) |
5-10 minutes |
Continuous production requires ≤10 minutes |
| Adhesion (Cross Hatch Test) |
3B-4B (with pretreatment needed) |
4B-5B |
≥4B (ASTM D3359) |
II. Adhesion Performance of Water-based Ink in Screen Printing
(I) Key Factors Affecting Adhesion
- Substrate Material: The substrates of different materials have a great impact on the adhesion of water-based ink. On cotton fabrics, the water in the water-based ink can penetrate into the fiber interior. After the water evaporates, the film-forming substances in the ink will combine closely with the fibers, thus obtaining good adhesion. However, on the surfaces of some smooth plastic materials such as polypropylene (PP) or polyethylene (PE), due to their low surface energy, it is difficult for water-based ink to adhere. Usually, the plastic surface needs to be pretreated, such as corona treatment, plasma treatment, etc., to increase the surface roughness and polarity and improve the ink adhesion.
- Ink Formula: The resin in water-based ink is the core component determining the adhesion. Acrylic resin, polyurethane resin, etc. are commonly used in water-based ink formulas. Taking acrylic resin as an example, acrylic resins with different structures and molecular weights have different adhesion performances on different substrates. Some specially modified acrylic resins can form chemical bonds or physical adsorption with various materials, significantly enhancing the adhesion.
(II) Practical Methods for Improving Adhesion
In actual screen printing production, in addition to pretreating the substrate to improve the adhesion of water-based ink, the printing process parameters can also be optimized. In terms of ink preparation, it is necessary to operate strictly in accordance with the formula requirements to ensure the accuracy of the proportion of various components, so as to ensure the stability of the ink performance and the reliability of the adhesion.
| Material |
Pretreatment Solution |
Target Dyne Value (mN/m) |
| Polyester Textiles |
Plasma treatment (power 300W) |
≥54 |
| PET Plastic |
Coating with water-based primer (3g/㎡) |
≥48 |
| Glass |
Soaking in silane coupling agent (KH-550) |
≥56 |
III. Drying Challenges of Water-based Ink in Screen Printing and Solutions
(I) Analysis of Drying Challenges
- Slow Drying Speed: Compared with solvent-based inks, the drying speed of water-based inks is relatively slow. This is because water has a high latent heat of evaporation and requires more energy to volatilize. In the screen printing process, if the drying speed is too slow, it will lead to low printing efficiency. There may also be problems such as ink smudging and sticking, affecting the printing quality.
- Great Influence of Environmental Humidity: Environmental humidity has a significant impact on the drying of water-based inks. In a high-humidity environment, the evaporation of water is hindered, and the drying time of water-based inks will be greatly extended. In seasons with high humidity, if the humidity exceeds 80%, the drying speed of water-based inks may be several times slower than under normal conditions, seriously affecting the production progress.
(II) Effective Measures to Solve Drying Challenges
- Optimizing Drying Equipment: Using suitable drying equipment is the key to solving the drying problem of water-based inks. Hot air drying is one of the commonly used methods. By blowing hot air onto the printed substrate, the evaporation speed of water is increased. The temperature and air volume of the hot air can be adjusted according to the material of the substrate and the printing speed.
- Controlling Environmental Humidity: Installing dehumidifying equipment in the printing workshop and controlling the environmental humidity within the appropriate range of 40% - 60% is helpful for the drying of water-based inks. Reasonably arranging the ventilation system of the workshop to timely discharge the water vapor generated during the drying process and maintaining the stability of the relative humidity of the air can create good conditions for the drying of water-based inks.
| Drying Method |
Temperature/Time |
Energy Consumption (kW·h/㎡) |
Applicable Materials |
| Infrared Pre-drying |
60℃×2 minutes |
0.8 |
Paper/Cardboard |
| Hot Air Main Drying |
80℃×5 minutes |
1.2 |
Textiles/Plastics |
| UV Curing (Optional) |
200mJ/cm²×10 seconds |
0.5 |
Products with High Resistance Requirements |
IV. Environmental Advantages of Using Water-based Ink in Screen Printing
(1) Low VOCs Emissions
Traditional solvent-based inks will release a large amount of VOCs during use. These volatile organic compounds will not only cause pollution to the atmospheric environment and form hazards such as photochemical smog but also have adverse effects on the health of the operators in the printing workshop. Water-based ink uses water as the main solvent, and its VOCs emissions are extremely low, which complies with the current environmental protection regulations. It reduces the environmental compliance costs for printing enterprises and contributes to improving the working environment and atmospheric quality.
(2) Biodegradability and Utilization of Renewable Resources
Many components of water-based inks have biodegradability. The resin in some water-based inks is made of bio-based materials, which are derived from renewable plant resources, etc. After the ink is discarded, it can gradually decompose in the natural environment, reducing pollution to the soil and water bodies.
V. Conclusion
Water-based ink has broad application prospects in screen printing. Although there are some challenges in terms of adhesion and drying, through the pretreatment of the substrate, the optimization of the ink formula, the adjustment of the printing process parameters, and the adoption of suitable drying equipment and environmental control measures, these problems can be effectively solved.
Its remarkable environmental advantages, whether from the protection of the atmospheric environment by low VOCs emissions or the contribution to sustainable development through biodegradability and the utilization of renewable resources, make it an ideal choice for the screen printing industry to achieve green development.
RU
EN
CN
