We quiz Folker Stachetzki, of Brother, about the ins and outs of direct-to-garment printing on polyester

Direct-to-garment printing on polyester? Surely DTG is limited to printing on cotton fabrics?

DTG is constantly changing and what once seemed impossible is now reality. It has always been a special challenge to apply water-based ink to polyester using the DTG process without changing the process too much, having to use other inks or making qualitative cuts. Brother has been working on this process for a long time, focusing on solving the challenges mentioned above, and we can now offer our solution to the market.

So, what type of garments and accessories can now be printed using DTG machines?

With the printing of polyester, we have opened up a whole new market with countless possibilities for our customers. At the moment, the football fan sector is booming, driven by the UEFA European Championship. Personalised fanshirts are a big hit and will remain so after the finals. The entire sports sector is very interesting due to the high amount of polyester clothing and the fact that very often small to medium runs are being personalised (club jerseys, etc). The workwear market is also very promising. From workwear with logos to safety waistcoats, there are almost no restrictions [see below].

How does DTG printing on polyester work?

The key to success is to block the dye from the polyester fabric from migrating into the ink. This means applying a larger amount of pretreatment, and increasing the amount of passes and the printing time to give the ink time to bind. With our solution, this means that the print file has to be created via a special polyester driver (available free of charge at all certified Brother dealers). Then you pretreat twice to get the required amount of fixation on the garment. All in all, the printing process takes a little longer than when printing on cotton. It is also very important that the textile is washed afterwards to achieve a very high wash resistance.

So I can use my existing DTG printer and inks for printing on polyester?

There are generally two different approaches to DTG printing on polyester: one is to use a special machine that prints only polyester, the other is to use the same machine that is used for cotton printing. Both approaches work fine, the customer’s preference will depend on their workflow. Brother has decided to remain flexible and offer polyester printing without additional investment. To come back to the question – you can use the same inks, the same pretreatment and the same printer. Only the settings are different from those used for cotton printing.

Is DTG printing limited to printing on white and light substrates, like sublimation printing?

Absolutely not. From the beginning, our aim was to have as few limitations as possible. Before the release, we tested all common colours and found no real limitations in the colours that can be printed. White, black, neon, red… it makes no difference.

Do you need to use different pretreatment for white and dark polyester fabrics?

There are different approaches to pretreatment too. We decided to make it possible to use the cotton pretreatment. This was one of the most difficult parts of the development. The difference between polyester printing and cotton printing is the mixing ratio of the pretreatment. But since most pretreatment machines have two tanks anyway, this is not really an issue. Also, if there is only one tank, the tubes do not have to be cleaned.

Are there any limitations to DTG printing on polyester? For example, can I DTG print on super-stretchy performancewear without the inks cracking?

We have found that our inks perform very well on many common polyester materials. Of course, with super-stretchy garments, any ink will reach its limit at a certain point. It is also not possible to print on water-repellent treated textiles. We recommend that you test the material beforehand.

How does the cost of DTG printing on polyester compare with that of DTG printing on standard cotton fabrics?

Since no additional equipment is needed and the driver software is free, there are no purchase costs. More pretreatment is needed for fusing, however the ink consumption is reduced when printing on polyester compared to cotton. What you certainly have to consider, and what can make a difference in the final costs, is the time factor.

What’s your best piece of advice for anyone thinking of using their DTG printer to print on polyester fabrics?

Try it out – be creative. A whole new market is open for you, just waiting for great, colourful, uniquely printed polyester products!

www.brother-industrial.com