ROHM Thermal Printhead Delivers Long Service Life on All Thermal Recording Paper Types


Kyoto, Japan – Semiconductor manufacturer ROHM CO., LTD., has developed the KD2003-DF20A thermal printhead featuring a highly durable protective film. The company began shipping samples of the part, whose protective film offers approximately three times the wear resistance of previous models and prevents both scratching and galvanic corrosion of the head, in January (sample pricing: ¥3,000 per part) and expects to begin mass production at a monthly volume of 100,000 units in March 2011 at ROHM Electronics Dalian Co., Ltd., (located in Dalian, China).

The miniaturized printer market has grown with the worldwide adoption of technologies such as POS systems, EFT systems, and CAT terminals, driving sustained growth in demand in the thermal printhead market. A trend toward use of low-cost thermal recording paper in this type of printer in response to operators' desire to lower maintenance costs has led to the use of some paper types with poor surface characteristics that cause abnormal wear, scratching, and galvanic corrosion, reducing thermal printhead service life.

While manufacturers have tried to address this problem by using harder materials to manufacture the printhead's protective film, increasing the film's strength raises issues in terms of its composition and the shape of the heat-producing part of the head. In some cases, existing products have been rendered unusable after about 10 km of printing distance-depending on the frequency with which the printer is used, as little as several months-when certain low-quality thermal recording paper is used.
To overcome these challenges, ROHM has made improvements both in the structure of the hard substances in the protective film material and in the head design itself. By optimizing the substances that make up the protective film material and their composition, ROHM was able to dramatically improve the new thermal printhead's wear resistance and deliver approximately three times the durability of previous models (allowing a warranty of 150 km compared to 50 km for previous models).
Furthermore, the new design delivers a 15% improvement in print efficiency over older models as well as better print quality thanks to an increase in the protective film's thermal conductivity. As an additional advantage, the new printhead uses the same shape as previous models, eliminating the need for manufacturers to change printer designs and allowing the new part to be used to replace damaged printheads in existing printer models.

ROHM has earned high praise from customers for leveraging its accumulated semiconductor technology and thick- and thin-film deposition technology to create a portfolio of products that meet needs such as high print speed and quality in a broad range of markets, including POS terminals and label printers. The company drew on this extensive array of technologies to develop the KD2003-DF20A, which will allow customers to enjoy maintenance-free system operation and improved print quality.

Principal features of the KD2003-DF20A thermal printhead

  1. High wear resistance (abrasion life:150 km)
  2. High scratch resistance
  3. 15% improvement in print efficiency
  4. High corrosion resistance

Comparison of protective film wear

Wear Resistance Evaluation (based on actual printing tests)


  1. Scratching (SiC)
    Damage sustained by the thermal printhead due to the ingestion of foreign matter. When foreign matter is caught between the platen and the thermal printhead, it may scratch the surface of the printhead. Large scratches can affect the resistance of the heating element, causing issues such as white lines in print.
  2. EFT (electronic funds transfer system)
    A system for electronically debiting bank accounts. EFT systems allow funds to be moved between accounts or used to make payments. Capabilities of the system include account access via cash dispensers and ATM machines, online banking services for homes and businesses, automatic debits using magnetic strips on cards, and online, real-time debits when making purchases with cards such as the Visa Electron card.
  3. CAT (credit authorization terminal)
    A type of terminal used by merchants to verify customer credit for purchases. Stores with CAT terminals are linked to card issuers via phone lines or the Internet, allowing businesses to verify that cards are not lost or stolen and to check expiration dates and credit limits.