Product DescriptionCarbon Materials Dispersion Technology + Hybrid Technology

As the push toward creating an IoT and a trillion sensor society accelerates, the Toyo Ink Group proposes a sustainable self-powering systems that convert minute thermal energy such as exhaust heat from factories and body heat into electricity.

By using our printable organic materials, our researchers have developed thermoelectric materials that exhibit excellent processability and usage versatility, and can be applied to various situations such as flexible curved surfaces and wearable electronics.

Product Features

Product Characteristics: Organic vs. Inorganic Thermoelectric Modules

Although their output power is smaller than that of inorganic devices, Toyo Ink Group’s organic modules exhibit high integration, light weight and flexibility of the printing process, making it possible to save space, arrange curved surfaces, and implement wearable devices.

Developed products
(Organic thermoelectric module)
Conventional products
(Inorganic thermoelectric module)
(At 25℃ / 80℃ temperature difference)
μW mW
Output voltage
(At 25℃ / 80℃ temperature difference)
1V 0.12V
Weight 5.3g 22.5g
Occupied volume 3.6cm3 6.1cm3
Flexibility Good
(No degradation in performance when r = 0.5 to 2 cm wrapped)
Printing Process Suitable Not suitable


Example 1: Self-powered systems for various edge sensors

Application image: Power source for smart factories and infrastructure sensors

Example 2: Wearable sensors

Application image: Skin for robots, environmental sensors

Technology OverviewHybrid Technology + Dispersion Technology of Carbon Materials

The Toyo Ink Group has developed organic thermoelectric conversion materials with excellent flexibility and printing characteristics (patterning, large area) and is in the process of applying prototype materials in the creation of thermoelectric conversion modules. Our researchers focused their attention on materials engineering and adopted carbon nanotubes (CNTs) with excellent thermoelectric properties and high electrical conductivity. By combining them with our proprietary organic materials, we were able to further improve CNT properties. The performance of the new thermoelectric conversion materials is evaluated by the power factor (PF: power generated per unit temperature difference). The PF value is obtained from the product of the Seebeck coefficient that indicates the electromotive force per unit temperature difference and the electrical conductivity. However, there is usually a trade-off between Seebeck coefficient and conductivity. To address this issue, we achieved high PF values by combining both Seebeck coefficient and conductivity at a high level by leveraging our unique hybridization technology that enhances the electronic interaction between CNTs and organic materials, and our CNT dispersion technology that constructs an optimal conductive path in the coating film.

PF:Power Factor (W/mK2)
S:Seebeck coefficient (V/K)

(Figure) Ideal film for improving thermoelectric conversion performance (PF)

Hybrid Technology

・Energy level control

We specially engineered the HOMO/LUMO energy levels of the organic materials for greater control of the electronic interactions such as the charge carrier transfer between carbon and organic materials.

・Adsorptive property control

By incorporating skeletons that interact with carbon materials, we can improve the adsorptivity to carbon materials and enhance the hybrid effect.

Improve thermoelectric performance by enhancing the electronic interaction between carbon and organic material.

Carbon Materials Dispersion Technology

By controlling the carbon material in an optimal dispersion state using our original dispersant and formulation, we achieved high conductivity (mobility) by inking the thermoelectric material and optimizing the conductive path in the coating film.

SEM image of coated film
Ink dispersion viscosity

Enhancing Electron Interaction between Carbon and Organic Materials to Improve Thermoelectric Performance

Flexible organic thermoelectric conversion materials

  • p- and n-type materials with high thermoelectric performance (PF: 270 μWm-1・K-2 <)
  • Can be applied by inking

Toyo Ink SC Holdings Co., Ltd Inquiry for Organic Thermoelectric Materials and Flexible Modules

※Required fields must be filled in.

E.g. Robert
E.g. Smith
If you are not an employee or student, please state "Individual."
Select from the list