Archives for posts with tag: thermal transfer

Pen has become a universal word. We no longer say fountain pen or ballpoint pen. But could we imagine a ballpoint pen without the spherical point?

Not quite. What is nowadays a simple thing we take for granted, was born after years of experimentation and analysis.

The first patent on a ballpoint pen was issued on 30 October 1888, to John Loud, a leather tanner, who needed a writing instrument that could write on his leather products. Obviously, fountain pens couldn’t do that. But because the instrument could not be used for writing letters, (they were way too coarse) it did not gain commercial usage.

László Bíró, was a frustrated Hungarian newspaper editor. Frustrated because he had to spend too much time filling up fountain pens. So something had to be done. Receiving help from his brother, a chemist , Bíró fitted his pen with a tiny ball in its tip that was free to turn in a socket. As the pen moved along the paper, the ball rotated, picking up ink from the ink cartridge Bíró filed a British patent on 15 June 1938.

What do ballpoint pens have in common with print heads?

A lot. Imagine thermal printers without thermal print heads. The truth is the entire functionality of a thermal printer lies in its print head. Their precision is responsible for the quality of their output. That is, the better the quality of a thermal print head, the better the quality of the printed text.

Thermal print heads are mainly used in the industrial labelling sector.  Bar codes and price tags also use the thermal transfer printing system and implicitly the thermal print heads.

As the barcode is now universal and used beyond its initial commercial purpose, barcode printing is an everyday process that needs to rely on quality thermal print heads. The very first scanning of the famous barcode was of a Wrigley chewing gum in June 1974.

Barcode printing can either use the direct thermal printing method or the thermal transfer printing one. Although a bit less expensive, direct thermal printers produce labels that can become illegible if exposed to heat, direct sunlight, or chemical vapors. Needles to say, the print heads used in the thermal transfer printing type produce a more accurate, long lasting image.

For those interested in the latter option, www.als-store.co.uk, as approved partners, is able to supply various thermal print heads like Avery Dennison and Zebra. Other consumables, thermal transfer labels and ribbons can also be found here.

It all started in the 15th century when the skilled Johannes Gutenberg devised the movable type printing technology. This was the first major revolution that determined the course of culture and communication. Centuries later, we have the photocopier, the thermal printer and the laser printer.

A thermal printer produces a printed image by selectively heating coated thermal paper when the paper passes over the thermal print head. The coating turns black where heated and an image is thus produced.

In theory, it sounds easy, and even in practice this is easy, but only because others thought hard of how to make this mechanism possible. One of the reasons it’s possible and so easy is due to the thermal print head which is responsible for a line of controlled dots of heat which will produce an image in conjunction with heat sensitive ribbons or paper.

Since they are direct responsible for the actual image we can see on various items, mainly labels, the quality of the thermal print heads has to be one of the best. Let’s just say they have to cope with a very demanding and fast paced environment. Not properly maintained or badly manufactured, they will generate text that is difficult to read, unacceptable now when consumers have to be informed as most accurately as possible about the product they are about to purchase.

How Does Thermal Transfer Ribbon Work?

Thermal transfer printing is a fast and clean process with no warm-up or cooling time required. It is not a wet or dirty process either and the results are instantly dry, requiring no curing. By using a single-pass ribbon, the print is perfect from the start to the very end of a roll, making it the standard for producing barcodes and variable information labels, on-demand.

A thermal transfer label printer from the likes of Avery, Sato, TEC, Zebra etc produces text, barcodes and graphics by using a fixed low-powered print head which spans the entire width of the print area. The print head comprises of a single row of thousands of tiny elements (“dots”) of a size typically 8 or 12 dots per millimetre, yielding a print resolution of 200dpi or 300dpi – but even 600dpi is available.

The Difference Between “Direct Thermal” and “Thermal Transfer”:

A Direct Thermal printer uses the heat from the dots in the print head to activate a chemical coating in a specially produced thermal label, which darkens the area in contact with each dot, in order to produce the label image.  A Thermal Transfer printer uses a thermal ribbon:-

Thermal transfer ribbon is a roll of clear plastic (PE) film coated on one side with a coloured pigment, or “ink”, most commonly black (although many colours are available). Depending on the printing requirements, the coating can be formulated using either wax, resin or a mixture of both. The thermal transfer ribbon passes over the thermal print head, with the coated side pressed against the label surface. The heat energy produced by each dot causes the pigment to transfer off the carrier film and bond to the surface of the label.

The element dots which make up the print head are electronically heated up and cooled rapidly by the printer as both the label and ribbon pass under it at the same time. Speeds of 300mm per second and faster are quite achievable with the right match of ribbon, label and printer.

There are many aspects we encounter on our daily life that we pay very little towards or no attention at all, accumulated aspects that helps us create the sophisticated life style that many of us live today. Thermal transfer is one of those aspects that are encountered on a daily basis in various situations from the beginning of a day to the end of the night.

So what is this thermal transfer? Thermal transfer is a printing technology used by the printing industry. It involves printing on paper and other materials by melting a coating of ribbon so it stays glued onto the surface where it is applied. The quality of labels varies depending on the nature of the labels usage. This varies from day to day commercial use such as postage and packaging to industrial hazardous chemical use.

In the morning when checking the post, the labelling used on the letters are encounters of thermal transfer printing. Some labels have different durability purposes, whereby the post stamp itself is designed to be able to survive weather with minimal exposure to rain and water before the item is distorts. The material of the printing is determined by the type of thermal ribbon and the surface material used.

The stamp can be used with wax-resin ribbons where it is designed to last a long time, but should not be in direct contact with liquids such as water, oil or chemicals which would dissolve its image. Thermal transfer printing uses three different types of ribbons which are wax ribbon, wax-resin ribbon and resin ribbon.

During the rest of the day, encounters of thermal transfers will continue as the vast majority of packaged products today have used complex printing methods. Other products such as magazines will also use thermal transfer printing for various samples. Packaging is a vital part of a successful product in today’s competitive market where consumers are short on time and laden with choice.