Can't Lower the Return Rate? Key Details to Check in DTF Printing

Can't lower the return rate? The pattern is peeling off, not fine, and feels dry and empty without adhering? This should be a problem that many DTF printing enterprises have dealt with either their users or themselves. But most of the problems are not that the ink is bad, but that these few details during the printing process were not done well!

1. Whether the Printing Ink Volume Matches the Curing Parameters

The habitual use of "full ink" and "highlight mode" can easily lead to overink, affecting adhesion. Excessive ink content will cause the surface layer of the pattern to not be fully cured, and it is prone to bubbling or delamination during subsequent hot pressing. Improper setting of printing parameters is one of the common reasons for the shedding of powder and film in patterns. If the printing speed is too fast and the curing time is insufficient, it will result in the ink not adhering fully to the transfer film, thereby affecting the adhesion of the pattern.

Solution

1. Adjust the printing speed: Ensure the printing speed is moderate, usually recommended to be between 150 and 250 mm/s.

2. Optimize the ink volume: Adjust the ink volume according to the complexity of the pattern and the material properties to ensure full coverage.

3. Extend the curing time: Appropriately extend the curing time to ensure that the ink is fully cured. For UV ink, the curing time is usually between 10 and 20 seconds.

Tips: It is recommended to conduct 2 to 3 small sample tests before turning on the machine to confirm that the printing status is stable.

2. Whether the Superimposition Sequence of White Ink and Colored Ink is Correct

The sequence of ink layers affects the pattern formation effect and adhesion performance.

Solution

1.The correct sequence should be: White ink as the base → Colored ink for coloring

2. Optimize the printing parameters

(1) Thickness of white ink: Recommended between 20 and 30 microns. Too thin affects coverage; too thick affects curing and adhesion.

(2) Thickness of colored ink: Typically 10–20 microns to ensure bright colors and rich details.

3. Curing time

(1) White ink: Cure for 10–15 seconds before printing color ink.

(2) Color ink: Cure for 15–20 seconds after printing.

Tips: Use the software’s preset function for multi-layer calibration.

3. Whether the Hot Pressing Time, Temperature and Pressure Are Set Precisely

Improper control of hot pressing directly affects whether the pattern is "locked up". It is a common cause of powder shedding and film delamination if time, temperature or pressure are off.

Solution

1. Adjust the temperature: Typically 130–150℃ depending on material.

2. Optimize the pressing time: 20–40 seconds depending on pattern complexity and film thickness.

3. Adjust the pressure: Maintain within 3–5 bar for firm transfer.

Tips: Record the optimal settings per material type and adjust for different film thicknesses or machine power levels.

4. Whether the PET Film Used is Compatible

Even the best ink and design will fail if paired with incompatible film. Poor PET film leads to demolding and weak adhesion.

Solution

1. Choose high-quality PET films:

(1) Brand: Choose reliable, market-verified brands.

(2) Uniform coating: Ensure even, defect-free film surface.

(3) Compatibility test: Always test before bulk production.

2. Check shelf life and storage:

(1) Expired film may have poor coating performance.

(2) Store in dry, cool conditions to prevent degradation.

Tips: Use A-grade PET film with cold-peel smoothness and no static. For special effects, consider matte or thick film.

5. Whether the Type of Hot Melt Powder and Coating Method Are Scientific

Hot melt powder is critical to adhesion. Uneven powder will cause irregular melting and transfer failure.

Solution

1. Test the powder:

(1) Small-batch testing for adhesion and durability.

(2) Environmental testing: Wash, UV, and abrasion simulations.

2. Optimize coating method:

(1) Powdering:

① Even distribution whether automatic or manual.

② Gently shake or tap to remove excess powder.

(2) Spraying:

① Adjust pressure and flow for even spread.

② Control drying to prevent residue.

Tips: Use general powder for cotton; elastic powder for stretch fabrics.

The development of DTF technology is accelerating the promotion of "on-demand customization" and "small-batch quick response" models. But stable print quality is what truly drives customer retention. By solving the key factors above, your DTF output will be fuller, more durable, and more stable.

If you need test samples, material suggestions or printing settings, feel free to contact us for personalized support and guidance.