DTF (Direct Transfer Film) printing is a new textile printing method in current market. It has similar printing outcome as DTG (Direct to Garment) printing, however DTF printing is extremely flexible and versatile. It can print on a large range of material such as nylon, polyester, denim, silk, and cotton. Unlike DTG printing is limited to cotton-based material only.
Beside versatile and flexibility, DTF printing combine reliability, unmatched quality and high productivity. It handles large production volumes, which is essential in this fast-growing industry.
DTF is a revolutionary new printing technique that's more affordable and accessible compared to DTG, screen printing, sublimation or laser white toner transfers. DTF required a special printer and DTF ink to print the image on PET transfer film. With DTF you can transfer to 100% cotton shirts without pre-treatment, saving a lot of money and time. DTF is washable unlike laser toner transfers and it feels a lot better to the touch.
How DTF printing works
Step 1 – Print on PET Film
Insert the PET film in the specific printer. Print the entire image on the pet film. There are 2 layers printing to perform by the printer. First layer prints the CMYK image, follow by second layer to print white ink on top of the CMYK image. Due to the image will be transferred to the fabric later, therefore all images printed on PET film must be mirror-image.
Step 2 – Powdering
This step is the application of hot-melt adhesive powder on the film that has the printed image on it. The important thing is to ensure that the powder is evenly spread all over the printed surface on the film. Basically this process is done by automated powder shaker machine.
Step 3 – Curing the powder with printed image
This main purpose for this process is to make the adhesive powder become half melt so that the powder can mix with printed ink then dry out together. The most common way is to apply appropriate heat on both printed image and the powder. For best results, it is highly recommended to go by the manufacturer specification for powder melting point.
Step 4 – PET film completed
Finally, the DTF film with printing is completed. In short, the printed images is just temporary stay on the PET film. Later, the image will be transfer to fabric by using the heat press process. "
Heat Transfer to Fabric
Step 1 – Pre-pressing
The step involves pre-pressing of the fabric by using heat press machine. The fabric is kept in the heat press and pressurized under heat for about 2 to 5 seconds. This is done to flatten the fabric and also ensure de-humidification of the fabric. The pre-pressing helps in proper transfer of the image from the film on to the fabric.
Step 2 – Heat Press Transfer
This is the heart of the DTF transfer process. The PET film placed on top of the fabric, then apply appropriate temperature and pressure by using heat press machine. This process allows adhesive powder start melting in between fabric and printed ink. Of course, we must allow enough time for the powder to melt completely. Any mistake on this process will cause damage on fabric and reliability issue.
Step 3 – Cold Peel
It is important that the fabric and the now attached film on it cool down to room temperature before pulls the PET film off. After peel off the PET film, the printed image will stay on the fabric.
Step 4 – Post-pressing
To ensure that printed image can stick on fabric permanently and improve reliability, it is important to perform post-pressing for around 10 second. "
Advantage and Disadvantage of Direct to Film Printing
Works with almost all types of fabrics
Does not require pre-treatment The Fabrics thus designed exhibit good wash characteristics.
The fabric has very slight hand feel touch
The process is faster thus shorter production lead time
The feel of the printed areas is slightly affected when compared to that of fabrics designed with Sublimation printing
As compared to sublimation printing, the color vibrancy is slightly low.