Matters Needing Attention in DTF Heat Transfer Scheme

Nov 29-2021

1. Coating offset heat transfer process

The paint offset heat transfer process is to print water-based paint ink and white ink directly on the medium of PET transfer film. The printer is connected to a duster. After the PET transfer film is printed, it goes through the duster and sprinkles hot melt glue on the corresponding pattern. Powder, and finally dry, fix color and roll up in one step. And it does not limit the fabric, the scope of application is wider, and the color does not fade or fall off after washing.

With the mass production and practical application of different printers on the market, new problems are slowly emerging. Below we analyze and summarize various emerging problems and solutions for you.

The first emerging problem is: after the pattern is dried, the transfer fails during the transfer process, and the pattern cannot be firmly adhered to the fabric. Many printer users are analyzing and researching why. In fact, the reason is very simple, only hot melt powder is responsible for the task of bonding. That must be his responsibility. But why sometimes it sticks and sometimes it doesn't?

In response to this problem, our R&D department has repeatedly researched, tested and analyzed. Get a little experience. We believe that there are two reasons for the transfer failure. The first is: the problem of hot melt glue powder. The choice of hot melt powder plays a vital role in digital printing dusting, sticking, shaking and final pressing. The quality of hot melt powder directly determines the success or failure of your customers in the final transfer. Therefore, you must be careful in the selection of hot melt powder. The proportion of hot melt powder in the entire digital printing consumables is very small. Don't make more losses in order to reduce this cost!

2. How to choose hot melt powder?

It needs to be decided according to the second reason, that is, the fabric to be transferred, the size of the pattern and the application scene. The flatness of different fabrics is very different. For example, pure cotton fabric has good flatness and high density. It is easy to iron and press with ordinary hot melt powder, because the hot melt DTF transfer powder has a large bonding area with pure cotton fabric per unit area, and there is no gap. The more the amount of bonding, the better the firmness is naturally. On the contrary, for example, mesh knitted fabrics such as POLO shirts, sunscreen clothing, etc., have uneven surfaces, even gaps, and some do not have a waxy layer on the surface, which is not bonded to hot melt powder. At this time, it is not appropriate to use ordinary hot-melt adhesive powder, and ordinary hot-melt adhesive powder cannot achieve the ideal bonding strength.

In response to this problem, we have done a lot of work, and finally found a solution that can be solved: use different hot melt powders for different fabrics. First of all, for pure cotton fabrics or fabrics with good flatness, you can use ordinary hot-melt powder for digital printing. Adhesive enough to handle firmness requirements. For mesh fabrics or other fabrics that are not suitable for bonding, the hot melt powder must be exchanged decisively, otherwise the complete pattern cannot be avoided.

For types of fabrics that are not suitable for bonding, we have developed a high-viscosity hot-melt powder for digital printing. This hot melt powder is very sticky. It can complete the bonding task well for fabrics that are not easy to bond, but the disadvantages are also obvious. If the stickiness is strong, the feel will be hard, and the feel and stickiness need to be selected. It is possible to select it for transferring small patterns, LOGO, etc., but it cannot be selected for large-area patterns. Application scenarios such as: hat logo pattern, LOGO, small letters or text, etc.