Product Features:
1. Achieving a high wiring aspect ratio to contribute to the production of a display with higher image quality and larger size
As the need for a touch display with a higher image quality and larger size increases, a touch sensor placed on the display is required to maintain its touch function while maintaining the high image quality. Against this background, a transparent conductive film, which makes up the touch sensor, requires both low resistance and high transmissivity. However, with the ordinary etching method for manufacturing a metal mesh, there is a trade-off between low resistance and fine wiring. It achieves low resistance, but requires a greater wiring width, resulting in insufficient transmissivity. Meanwhile, by adopting its original roll-to-roll construction method, Panasonic has succeeded in forming a wiring pattern with a high aspect ratio that reduces the wiring width to 2 μm, which was difficult to achieve with conventional etching methods, thus developing a transparent conductive film combining low resistance and high transmissivity.
This technology enables the manufacturing of a touch display with a higher image quality and larger size, and contributes to development of a design-free transparent antenna utilizing transparency.
Fig. 1 Panasonic's original roll-to-roll construction method
Fig. 2 Electron microscope photos showing the surface and cross-section of a wiring line manufactured by the original construction method
2. Double-sided full wiring that offers high coordinate accuracy and improved flexibility
Conventional capacitive touch sensors are manufactured by laminating together two films, one for the transmission electrode and the other for the reception electrode. This manufacturing method has a problem whereby the positional accuracy of both electrodes depends on the mechanical precision of the laminating device and the viscosity of the adhesive. Panasonic, on the other hand, has formed the transmission and reception electrodes on the front and back surfaces of a single film through double-sided full wiring patterning by using the company's original roll-to-roll construction method, thus succeeding in significantly improving the relative positional accuracy of the electrodes. Panasonic's method makes the device thinner, improving its bendability to make it more flexible.
3. Contributing to the reduction of environmental impact by reducing display's power consumption and using fewer materials
Panasonic's transparent conductive film allows fine wiring, thus achieving a high aperture ratio [3]. This increases the transmissivity of light emitted from the display, allowing the transparent conductive film to reduce its power consumption by about 4%, compared with a conventional transparent conductive film manufactured by an ordinary etching method, when both films are incorporated in displays with the same area and resolution.
In addition, by forming the transmission and reception electrodes on the front and back surfaces of a single film through double-sided full wiring patterning, a touch sensor can be created using one film, instead of two as is usually the case, thereby contributing to a reduction in environmental impact.
Table 1. Specifications
| Product name | Transparent conductive film |
| Wiring line | Width | 2.0 μm |
| Thickness | 1.5 μm |
| Transmissivity | 94％ |
| Sheet resistance | 2 Ω/sq. |
| Frame wiring L/S[4] | 8/8 μm |
| Base material | PET, PC, COP |
| Bendability | ≧R2 mm |
[Term Descriptions]
- [1]: Metal mesh: electrode consisting of a lattice of metal wires
- [2]: Aspect ratio: thickness to width ratio of a wiring line
- [3]: Aperture ratio: percentage of an opening per area
- [4]: L/S: wiring width (line) to interval (space) ratio of adjacent wires
For product inquiries, contact:
Electromechanical Control Business Division, Industry Company, Panasonic Corporation
https://www3.panasonic.biz/ac/e/user/new_question/index.jsp?ad=press20220216
Detailed product information:
https://ac-blog.panasonic.com/en/control/touch-panels/metal_mesh/special?ad=press20220216
Media Contact:
Panasonic Corporation Corporate PR Center
https://news.panasonic.com/global/contacts/
About Panasonic
Panasonic Corporation is a global leader developing innovative technologies and solutions for wide-ranging applications in the consumer electronics, housing, automotive, and B2B sectors. The company, which celebrated its 100th anniversary in 2018, operates 522 subsidiaries and 69 associated companies worldwide and reported consolidated net sales of 6,698.8 billion yen for the year ended March 31, 2021. Committed to pursuing new value through collaborative innovation, the company uses its technologies to create a better life and a better world for customers. Learn more about Panasonic: https://www.panasonic.com/global.
