DTF Printing: Addressing Oily and Moisture Issues for Optimal Results

DTF printing is a specialized heat transfer technology that uses dedicated DTF printers and consumables to transfer designs onto products like clothing. Compared to traditional printing techniques, DTF printing offers advantages such as flexibility, vibrant colors, durability, and the ability to achieve complex designs. However, with the increasing demand for quality and reliability, some users might encounter issues like oily and moisture after DTF transfer. Today, we'll discuss how to address these issues.

Understanding the Causes

The occurrence of oily, moisture, or bubbling in DTF printing is closely related to the printing process, materials used, and environmental conditions.

Process Factors

In the DTF printing process, after printing the white ink layer, DTF hot melt powder is sprinkled on it. Approximately 50%-60% of the moisture remains trapped in the ink layer at this stage. The DTF film then passes through a drying zone at 135°C to 140°C, where the hot melt powder melts into a glue layer, covering the ink. However, 30%-40% of residual moisture remains between the ink layer and the glue layer. Although the surface appears dry at this point, over time, the moisture and glycerin gradually seep out, causing the printed surface to look moist or oily.

Preventive Strategies

To minimize this issue, consider using DTF printers with a three-stage drying system:

Initial Stage (110°C): This initial temperature promotes moisture evaporation and starts the drying process without significantly melting the adhesive powder.

Intermediate Stage (120-130°C): This temperature range effectively dries the glycerin and other oily components trapped in the ink.

Final Stage (140-150°C): The highest temperature rapidly melts the adhesive powder, ensuring it binds tightly with the ink layer, enhancing the durability of the design.

In addition, insufficient temperature and time for powder curing, or application to non-breathable fabrics can easily cause oil seepage on the surface.

Material Considerations

The quality of materials is crucial for achieving perfect DTF prints. The materials used affect color accuracy, detail reproduction, durability, and even the final texture of the product.

Storage Tips

Since DTF films have a moisture-absorbing layer that readily absorbs moisture from the air, proper storage is essential. After each use, it is recommended to return the DTF film to its original packaging to avoid direct contact with the floor or walls. If the original packaging is not available, seal the remaining DTF film and store it in a well-ventilated, dry place.

Environmental Impact

A humid environment exacerbates DTF printing issues. Moisture in the air can affect the DTF film’s ink absorption, leading to uneven ink droplets and oily. Additionally, excessively humid conditions can cause ink to accumulate around the nozzles, clogging the print heads and affecting print quality.

Mitigation Measures

Regular Ventilation: Open windows or use exhaust fans to maintain air circulation and reduce the buildup of humid air.

Invest in a Dehumidifier: In high-humidity seasons or regions, deploying a dehumidifier can significantly lower indoor humidity levels.

Control the drying temperature: Control the appropriate temperature and time during the drying process. Too high a temperature will cause the ink to evaporate too quickly, while too low a temperature or too short a drying time will cause oily.

Best Printing Practices: Control the appropriate amount of ink used to prevent excessive moisture retention and oiliness.

Regular Maintenance: Keep the printer head clean to prevent nozzle clogging and ensure smooth ink delivery.

Careful Storage: Ensure all materials (including raw materials and finished products) are stored in dry, well-ventilated areas to minimize exposure to moisture.

In conclusion, achieving perfect DTF printing requires a comprehensive approach that addresses not only the printing process but also material and environmental factors. By implementing these strategies, you can minimize oiliness, bubbling, and other issues, ensuring your DTF prints consistently deliver excellent results.