Our digital garment prints are full colour and can include white ink. This allows us to heat press vivid designs on both light and dark coloured garments.
Please contact us to discuss you project or visit the studio to see some samples.
Welcome back to Exhibit Printing studio. Today we are going to be talking about t-shirt printing. Such as the t-shirt I’m wearing. We are going to be looking at two different approaches, both a laser printing transfer film and a more traditional cut vinyl heat press approach. So, as the heat press warms up we will go to the computer and look at artwork preparation.
So here we are at the computer. I’ve opened up illustrator and I have a graphic which I am prepping to cut. It is important with vinyl cutting that you have a vector image. The best way to describe a vector image is that it is a series of lines. If I were to zoom in, as I will demonstrate in a minute, on just a jpeg or bitmap image all I would have is pixels. There is no information there for a computerised cutter to follow. However, this image has been prepared by the graphic designer as a vector which gives me the option to cut it on the vinyl cutter. So I am going to take this file and open up my cutting software. I need to do two things here. I need to make sure the scale is correct as I want the graphic to be 18cm wide to fit on the t-shirt. It has already been prepared at that width which is great. The other thing needed is to make sure the graphic is in reverse. This is because the adhesive side is on the opposite side to what you would imagine. If you don’t reverse the image when you send it to cut or print, you will end up with a final product which is back to front. So I am about to send this graphic to cut. It is quite a detailed design and during process I will be able to demonstrate one of the weaknesses of a cut vinyl approach when it comes to efficiency in production. As you can see, the vinyl cut works by moving back and forth while feeding the media from front to back. You are able to adjust the pressure for different materials and the speed it can work at is quite impressive.
So we have moved over to a different work station now. I have opened up the same artwork, but as a bitmap (an image) in photoshop. I am going to zoom in to demonstrate the different here. Rather than the artwork being line work, it is just made up of pixels. There is no information here for a vinyl cutter or laser cutter to follow. However, there is another process called a transfer film, which is printed on the laser printer, that doesn’t need to be cut it just needs to be printed. So that is the option that we will choose here and then we will be able to compare the two.
The transfer film is just coming out of our OKI 5 colour machine. The fifth colour is white, which we have chosen to use for this project. So this is the point where we can demonstrate the major difference between a laser transfer film and a vinyl cut film. The laser transfer film is basically done and is ready to transfer onto a garment and the project is complete. The cut vinyl approach is just cut. It still requires us to do what’s called weeding, which is removing all the negative to leave us with just the graphic we desire. For this reason, a transfer film is far quicker, especially when you are doing areas which are highly detailed. The cut vinyl might be more appropriate for say the text on the back of a football shirt or a simple company logo. I will get back to you once I have weeded this.
So the hard work with the weeding is now done and the cut vinyl is now ready to press. I have a long sleeve cotton white top and the first step is to press it for about 15 seconds to remove any moisture. The t-shirt is now ready for the vinyl, so I will just place the graphic on and position it, making sure it is straight before lowering down the press. This is a hot peel, which means I will peel the release liner away as soon as possible. And there we have it, a transfer onto a t-shirt.
Although the transfer film was quicker to print and the cut vinyl took longer to weed, this transfer isn’t quite ready to be pressed onto the garment yet. We have printed onto what’s called an a sheet, but the adhesive which is going to finally bond it to the garment is actually carried on the b sheet. When we press them together, the clever part is that the adhesive will only transfer over to any areas on the graphic where there is toner. This means that you don’t get a square edge around your graphic like you do with a cheap DIY kit. Also, no effort was put into the weeding process (the manual effort that goes into the cut vinyl).
I have just heated up the bottom plate and I am going to place my a side print with the b side (cut slightly smaller to fit on top of it). I will then cover it with some greaseproof paper and press for 90 seconds. The next stage of this process requires me to remove the b sheet whilst it is still hot. This is in order to let it bond as well as possible to the ‘a sheet’. There is a bit of art to it, and it can be quite easy to get yourself burnt. Ok, that has gone quite well. You should be able to see that on the b sheet that the adhesive has been lifted on the areas where there was toner. This is then thrown in the trash. Although it is difficult to see, the back of the printed area now has an adhesive layer which is ready to be pressed directly onto a garment. This vinyl also takes 20 seconds to press. Unlike the cut vinyl, this particular transfer is a cold peel which means we don’t get to do the grand reveal until is has had a chance to fully cool. So, the graphic is fully cool now which means we can pull away the release liner. This product has a glossy appearance. You can just leave it like this but what most people do is put it back in the press with the special grease-proof paper over the top. This will flatten it out and the finish will be much like the cut vinyl approach.
So, here we have two different garments. Both similar graphics printed in two completely different ways. In this example we have used a single colour for both of these designs, however, it is worth noting with cut vinyl you can have metallic finishes and anything through to garish glitter finishes. With the digitally printed version, it doesn’t need to be one colour. It can be full colour such as a photo. There are no real constraints as to creativity if you choose the correct process when printing garments. I hope this information has been useful to you. If you have any questions do not hesitate to contact us at Exhibit Printing.