Why is sublimation color on fabric suddenly lighter?

There can be several reasons why the color transferred by a roller heat transfer machine may become lighter suddenly. Here are a few possible explanations:

1. Temperature issue: The rotary heat press machine might not be maintaining the required temperature consistently. If the temperature drops during the transfer process, it can result in a lighter color transfer. Users can observe whether the temperature on the temperature controller or touch screen drops a lot during the continuous transfer process. In addition, you can use a thermometer to measure the actual temperature of the drum to see if it is too different from what is displayed on the temperature control meter. Of course, what is measured is the temperature on the outside, and the temperature controller shows the temperature inside the drum. There will be a little difference, which is normal.

2. Pressure problem: Insufficient pressure applied during the transfer can prevent the color from transferring properly. This can lead to a lighter appearance. You can check to see if the air source is stable and whether the pressure on the pressure gauge continues to drop while the machine is in use. Also check to see if the pressure has been turned down.

3. Blanket tension: If the blanket becomes loose, it will cause the color becomes lighter than before. You need to press with your hand to check whether the blanket is too loose. You can try to adjust the blanket to make it tighter. It may also be that the blanket has reached the end of its useful life and still cannot be made tight enough within the adjustable range.

4. Speed inconsistency: If the transfer speed is different, it can affect the color transfer. Leaving the transfer paper on the fabric for too short a duration might result in a lighter color outcome.

5. Heat transfer oil problem: If your machine has been used for a long time, it is possible that the amount of thermal oil is too low and more oil needs to be added. If it is not locked with a high-temperature valve, the oil level can usually be directly observed with the naked eye. If there is a lot of smoke at the position of the fuel tank cap, it is usually caused by insufficient oil level. It could also be that the oil is too old and needs to be replaced.

6. Transfer settings: Incorrect settings on the machine, such as the speed or pressure, can impact the color transfer process. It's essential to ensure that the machine is set up correctly for each specific transfer job.

7. Substrate issues: The material being transferred onto could affect the color outcome. Different fabrics or materials may react differently to the transfer process, leading to variations in color intensity.

To troubleshoot the issue, you may need to check the machine's temperature, pressure, and timing settings. Additionally, ensure that the transfer process is compatible with the material being used. If the problem persists, it's best to consult the manufacturer or a technical expert for further assistance.