Heat Transfer Presses – an introduction
Heat transfer printing is used to create individual high-quality text or graphics images relatively inexpensively. From team sports to fashion apparel and all manner of personalisation in-between, heat transfer presses are the most important tool for this popular form of textile finishing.
While heat presses are often used to apply designs to fabrics, specially designed presses can also be used to imprint designs on mugs, plates, jigsaw puzzles, caps, and other products.
A heat press is used to permanently apply a heat transfer to a substrate. Popular transfer materials are Heat Transfer Vinyl cut with a Vinyl Cutter, Printable Heat Transfer Vinyl, Inkjet Transfer Paper, Laser Transfer Paper, Plastisol Transfers. Using a heat press to apply a transfer is the only way to ensure accurate time, temperature, and an even of pressure over the transfer, which are all essential to a successful and long lasting transfer.
The correct time, temperature and pressure also determine the success of Sublimation printing, a method that uses heat to transfer dye onto substrates such as a plastics, paper, or fabric. A successful transfer for this process results in a bright, colourful and lasting print.
In the following, we would like to give you an overview of some important transfer press equipment features.
The value of a heat transfer press
As a matter of principle, an investment should be in a healthy relationship with the available resources and expected revenues. However, consideration is also given to how long and intensive a press is to be used, how important the buyer is to aspects such as quality, safety, ease of use and support and whether and how quickly spare parts can be procured. For some users, the topic of sustainability or social aspects also play a role. The more important the buyer is to some of these points, the more a press will cost and be worth it, and thus the user more joy than grief.
Folding / clam press versus swiveling press…
The heat press manufacturers distinguish between two different opening types of transfer presses: vertically opening and horizontally swiveling presses (also known as a swing press). Vertical-opening presses offer the advantage that due to the shorter function path (flaps instead of pivoting), they enable faster operation. Moreover, the space requirement is less because no space is required for the lateral pivoting (the swing). The disadvantage is that the textiles cannot be positioned as easily on the printing plate as with a swivel press whose heating plate can be pivoted away beyond the printing surface. As a matter of experience, work is easier for beginners with a swivel press than with a clam press. In addition, a swivel press reduces the risk of accidentally touching the heating surface and causing burns.
Manual, semi-automatic or pneumatic presses?
Manual presses are devices in which the transfer process is initiated or terminated by lowering or opening the heating plate by hand. The transfer time is entered manually on the control panel and the time of unlocking is indicated by an optical or acoustic signal. Manual presses are especially useful for beginners and therefore suitable for small to medium runs. They are cheaper to purchase and still allow professional work.
Working with semi-automatic presses is more comfortable. Although the heating plate must be lowered manually to the pressure surface, it is automatically opened (thanks to an electromagnet) and automatically pivots to the side of some models. As a result, the operator has to apply less force for opening and pivoting compared to a manual press. At the same time, it can dispense with the acquisition of a compressor, as would be required with pneumatic devices, with a semi-automatic solution. Such presses are also suitable for small to medium runs.
Pneumatic presses are even more comfortable and efficient. They achieve a very high contact pressure. Printing is initiated at the touch of a button. After expiry of the timer, the device opens automatically without the operator having to pay attention. A higher contact pressure is particularly important with large area transfers or with certain sublimation pressures in which the manual pressure force is no longer sufficient. Pneumatic presses are particularly useful in high runs where the use of manual presses would be too strong. Pneumatic presses from Lotus usually operate at a pressure of 2.5 to 8 bar. A compressor is required for operation.
In all the described variants, a productivity increase can be achieved with the purchase of a press with two workstations. While one textile is printed, the operator can already pull the second one and prepare it for printing.
Traditional Heating coil or Mikanite Technology?
There are different heating coil technologies available. Curved single-piece heating elements are either installed in a heating plate (consisting of aluminum, cast iron or steel) or installed directly on the heating plates. The closer the heating coil curves are to each other, the better the temperature distribution. In the case of a defect, however, the entire heating coil or heating plate must be replaced. Lotus uses Mikanite surface heating elements. These are mainly used where a surface is to be heated quickly, effectively and evenly. The Mikanite heating technology records short heating-up times and a long service life of the heating elements. Due to the tight installation of the absolutely flat heating rods, an even, covering and optimal temperature distribution is ensured. The optimal adaptation between the heating element and the heating plate additionally ensures a very high operating life. In the case of a defect, the heating elements can be replaced individually at Lotus. The Mikanite technology saves costs and protects the environment. It is recommended to carry out an annual check to determine whether the heating temperature distribution of transfer presses used is still uniform or if it corresponds to the temperature indicated in the display. The easiest way to do this is by means of stick-on temperature measuring strips, which are available from specialist retailers.
CE marking is not a certificate
The EU is calling on all European producers and those who bring presses from outside Europe to comply with certain safety regulations. Corresponding conformity is documented by the companies with the CE marking. Buyers should bear in mind that the providers themselves prove the conformity of the devices themselves. It is therefore not an independent certificate, such as SGS or TÜV. In fact, not every device is equally safe. Prospective buyers should therefore take a closer view of whether the desired press actually complies with the UK safety standard and ask the dealer if they have any uncertainties.