Thermal transfer, thermal printing: the best choice for bar code printing

Today, the demand for bar codes has become indispensable. More and more goods use bar codes and variable data to transfer many product information, such as production date, storage location, delivery data, materials and styles. Such as stored in the trademark, therefore, the printing plant must strengthen the understanding of bar code printing technology, in order to actively meet the requirements of commodity packaging and logistics management.

In bar code printing, when it is necessary to print a stream code or variable information, because the cost of plate making is high, the traditional printing method can no longer meet the requirements. However, the speed of laser and ink jet printing is relatively slow, and there are many restrictions on paper, and it is not very applicable in industrial applications. Therefore, the use of computer-to-plate printing thermal transfer printing method has become the main solution for printing bar codes and variable information.

Printing principle

1. It relies on the heat generated by the print head to melt the toner on the ribbon to form text. Thermal transfer printing systems are mainly composed of thermal transfer printers (also known as barcode printers), ribbons (also known as ribbons), stickers (some high-end printers can also print a variety of computer tickets). The cooperation of these three parts determines the print quality. In addition, thermal transfer printers can also perform thermal printing jobs that are suitable for applications where the durability of labels and printed information is less demanding, such as supermarket price tags, which can often be accomplished using inexpensive thermal printing.

2. Thermal printing

Thermal printing requires the use of a dedicated thermal label to produce a corresponding color change based on the heat of the hair print to complete the print job. Since the thermal label itself is lower in price than the thermal transfer label, printing does not require the use of a ribbon, so the printing cost is relatively low. Labels that can be used for thermal transfer and thermal printing are classified into six categories based on their durability.

Hot print labels

1. Economical thermal label

Short service life, poor anti-fouling performance, typical application forms include: supermarket commodity price tag, warehouse logistics management tag, address tag and so on.

2. Coated thermal labels

It has a long service life, good anti-fouling properties, and is suitable for labels that have a slightly longer retention time, such as labels for dairy products and frozen foods, as well as labels printed in hospitals and laboratories.

3. Economic heat transfer label

Also known as ordinary coated paper labels, it is mainly applied to logistics and warehouse management.

4. Heat transfer label

Heat transfer labels are expensive, but they are still the preferred products of some large companies. They are often used in the packaging of brand-name products.

5. Thermal transfer polyolefin film label

The label is mainly made of white and transparent colored materials. Because of its softness, it is mainly used in the clothing industry, and it is attached to the clothing to mark the specifications and dimensions.

6. Thermal transfer PET tags

Mainly used in the electronics industry, such as product description of household appliances, serial number in the cell phone panel.

Currently available thermal transfer printers are classified into high-end industrial type, mid-range industrial type, and low-grade industrial and commercial dual-use type, depending on the print speed, resolution, print quality, and reliability.

Thermal transfer equipment performance

1. Print speed

The high-end industrial printer central processor is 64-bit or 32-bit. Due to the faster processing of pictures or texts, the printing speed can reach 10 to 16 inches/second; the mid-range industrial printer CPU is 32 bits or 16 bits, printing speed is 5-8 inches/second. The low-end industrial and commercial dual-use CPU is 8-bit, so the print speed is only 2-5 inches per second, and it is usually used for small batch printing.

2. Print resolution

At present, the resolution of thermal transfer printers on the market is mainly four types of 600 dpi, 400 dpi, 300 dpi, and 200 dpi. 300dpi resolution has been able to meet the bar code printing accuracy requirements, is the most commonly used models. When you need to print a fine picture, you can also use a higher-precision printer.

3. Print quality

The quality of thermal transfer printing is mainly reflected in the quality of graphic images at high speed. Most high-speed printers use the latest edge pressure printheads (also called hoverhead printheads). Its advantage is that the print head can move freely up and down, which is more flexible (it is not only easy to install and remove, but also can realize many special functions, such as high-speed printing and ribbon saving functions), easy to clean, good heat dissipation, and long service life. . The traditional flat pressure print head is not movable due to its location, heat dissipation is slow, dust is easy to accumulate, and its service life is relatively short. It cannot print at high speed and is only suitable for ordinary label printing.

4. Job reliability

Whether the printing position is accurate and the stability of the sensor, the rationality of the paper feeding structure, the firmness of the printer shell, and the printer's motor are closely related. The high-end printer has three super motors to move the paper, take the ribbon and the print head up and down, and the three parts can be synchronized or not synchronized, thus achieving the ribbon saving function in high-speed printing. Followed by whether the printer is an industrial design. This is related to the quality of the stepper motor, the number of power supplies, and the stability of the circuit board.

5. Special features

High-end printers have many special features to suit the needs of different occasions.

1) Save the ribbon. When the customer's label printing area only occupies a small part of the label, the ribbon saving function plays a role in reducing the cost of the ribbon.

2) Automatic print head inspection function. When printing large quantities of orders, the barcode of each label can be guaranteed to be accurately read. Even manual inspections cannot guarantee a 100% yield. With the print head self-test function, the printer will automatically detect the print head when it finishes a certain number of tasks to ensure the quality of the printed labels.

3) Replace the label and ribbon material prompts. When the label or ribbon runs out, the printer will issue a warning in advance to shorten the replacement time.

4) Double knife function. As long as customers add a cutting knife to the printer, they can cut every label and leave a margin for cutting. However, on special occasions, especially the tag label of the garment industry, all edges of the slitting need to be cut off after printing to leave a perfect label. The double knife function can achieve this effect.

5) Single sheet feeding mode. Although single-format printers have been commonly used in the printing of clothing labels, for some printing plants, reel-based printing is still the main method. Occasionally, there are small-volume single-sheet orders that can be printed on the printer. Add a single sheet feeder.

6) The scanner can print and scan once.

7) Automatic labeler. When the labeling speed is not very high, a sticker labeler can be installed on the barcode printer to complete the printing and labeling work at one time, thus saving hardware costs.

8) Print head width selection function. Using a machine with this feature when the label is very wide but the print width is very small will save the cost of the print head.

9) The print head unit is easy to replace. Usually the flat pressure print head needs to be replaced by a tool, which is troublesome. The edge pressure type print head is relatively simple, and it is only necessary to turn the positioning screw by hand.

As mentioned above, high-end industrial printers are suitable for large-scale, large-scale printing services, and special functions help reduce production costs. They are the preferred model for printing shops. The low-end industrial and commercial dual-use printers are suitable for small batch use in office applications.

ribbon

The printing effect is related to the matching degree of the ribbon and the label, in addition to the setting of the printer itself. High-speed printing must use high-speed ribbons (ie, edge-pressure ribbons). In general flat-press printing, flat-pressure ribbons are selected, and they cannot be mixed. Depending on the material of the label, the type of ribbon used is also different.

Source: hc360 HC Security Industry Channel