Products

Home  >  Products  >  Functional Materials: Electro-conductive Materials

Functional Materials

  • Contact us by
  • Email
  • Phone

Electro-conductive Materials ET·FT·FN·FS Series

Characteristics of ISK's electro-conductive materials

ISK's electro-conductive materials consist of antimony-doped tin oxide (ATO), which is an electron conductor. The materials show excellent conductivity and absorption of near infrared rays (heat rays).

The following four types of products are available.

  • ET series : White electro-conductive titanium dioxide, spherical type
  • FT series : White electro-conductive titanium dioxide, acicular type
  • SN series : Transparent electro-conductive materials, spherical type
  • FS series : Transparent electro-conductive materials, acicular type

ET and FT series are coated with ATO on titanium dioxide. Therefore, they have excellent whiteness and hiding power derived from titanium dioxide.

SSN and FS series are ultra-fine ATO. These are suitable for applications which need transparency.

Major applications :Anti-static applications (paints, fibers, plastic)

Click here for applications for heat ray absorption.

Grade variety

  Spherical type Acicular type
White electro-conductive titanium dioxide

Photo: ET series1. ET series

Photo: FT series2. FT series

Transparent electro-conductive materials

Photo: SN series3. SN series

Photo: FS series4. FS series

1. White Electro-conductive Titanium Dioxide, ET series

In ET series, spherical titanium dioxide is used as a core and it is coated with ATO layer. Basic properties are summarized in the table as below.

ET-500W and ET-600W are based on pigmental titanium dioxide (primary particle size : 0.25 µm), while ET-300W is based on ultra-fine titanium dioxide (primary particle size : 0.04µm).

Click here for properties of coating film

  ET-500W ET-600W ET-300W
Composition TiO2, SnO2(Sb doped)
Crystal form of TiO2 rutile
Particle size (µm) 0.2~0.3 0.2~0.3 0.03~0.06
Powder resistivity (Ωcm)1) 2~5 10~30 10~30
Specific gravity 4.6 4.5 5.0
Specific surface area (m²/g)2) 6~8 6~8 25~35
Oil absorption (g/100g) 15~20 15~20 25~35
Powder color :L value 84~88 88~92 70~80

1) 9.8 MPa compressed powder, 2) BET method.

Photo: ET-300W

Photo: ET-500W

2. Acicular Electro-conductive Titanium Dioxide, FT series

FT series are rutile acicular TiO2 coated with ATO layer, which is commercially produced only by ISK. Three grades with different sizes are available. The greatest feature of FT series is to be able to get the required conductivity with relatively lower content than spherical type such as ET series because of acicular shape. The use of FT series can reduce the content to 1/2~1/3 of spherical type. While there are several different types of acicular or fibrous conductive materials based on potassium titanate, FT series are not easily broken and have excellent stability of conductivity under various dispersion strength in comparison with other materials.

Click here for properties of coating film

  FT-1000 FT-2000 FT-3000
Composition TiO2, SnO2(Sb doped)
Crystal form of TiO2 rutile
Particle size (µm)1) D: 0.13
L: 1.68
D: 0.21
L: 2.86
D: 0.27
L: 5.15
Powder resistivity (Ωcm)2) 2~10 2~10 10~60
Specific gravity 4.4 4.7 4.3
Specific surface area (m²/g)3) 12~18 10~16 2~8
Oil absorption (g/100g) 40~60 40~60 50~70
Powder color :L value 85~90 85~90 90~95

1) Example of volume surface mean diameter measured with image analyzer. 2) 9.8 MPa compressed powder. 3) BET method.

D: Diameter, L: Length.

Photo: FT-1000

Photo: FT-2000

Photo: FT-3000

3. Transparent Electro-conductive Materials, SN series

SN products are fine ATO, whose primary particle size is about 0.02µm.

SN products are designed for usage in fields where both high transparency and electroconductivity are required.

Both powder type, SN-100P, and its water dispersion, SN-100D, are available.

In addition, dispersions in organic solvents such as toluene and MEK are also available.

Click here for technical data for SN series

  SN-100P (powder) SN-100D (water dispersion)
Composition TiO2, SnO2(Sb doped) TiO2, SnO2(Sb doped)
Particle size (µm) 0.01~0.031) 0.085~0.122)
Powder resistivity3)(Ωcm) 1~5 5~305)
Specific gravity 6.6 6.65)
Specific surface area4)(m²/g) 70~80 70~1005)
pH - 5.0~7.0
Concentration (wt%) - 30

1) Primary particle size. 2) Secondary particle size. 3) 9.8 MPa compressed powder. 4) BET method.
5) Data obtained from evaporated powder.

Photo: SN-100P

4. Acicular Transparent Electro-conductive Materials, FS series

FS products are acicular ATO which can achieve transparency and electroconductivity.

Due to the acicular shape, FS products can be used for coatings or plastics with less amount to obtain required electroconductivity compared with SN products.

Both powder type, FS-10P, and its water dispersion, FS-10D, are available.

In addition, dispersions in organic solvents such as toluene and MEK are also available.

Click here for technical data for FS series

  FS-10P(powder)) FS-10D(water dispersion)
Composition Sb doped SnO2 Sb doped SnO2
Particle size (µm) L: 0.2~2.0
D: 0.01~0.02
-
L / D (aspect ratio) 20~30 -
Powder resistivity1)(Ωcm) ~100 ~6003)
Specific gravity 6.6 6.63)
Specific surface area2)(m²/g) 25~35 40~603)
pH 2.5~3.5 8.0~10.0
Concentration (%) - 20

1) 9.8 MPa compressed powder. 2) BET method. 3) Data obtained from evaporated powder.

Photo: FS-10P

To top of page

Characteristics of ET and FT series

1. Relationship between content and conductivity

The relationship between content and surface resistivity, volume resistivity are depicted in figure 1 and 2 respectively.

The acicular FT-1000 and FT-2000 exhibit better conductivity at lower content than spherical ET-500W. Therefore, it can be said that conductive materials with anisotropy are more advantageous. In addition, FT-2000 which has larger acicular shape than FT-1000 shows better performance in conductivity.

Fig. 1.Content and surface resistivity (air-drying acrylic system)Fig. 1. Content and surface resistivity
(air-drying acrylic system)

Fig. 2. Content and volume resistivity (poly vinyl chloride system : twin screw extruder)Fig. 2. Content and volume resistivity
(poly vinyl chloride system : twin screw extruder)

2. Relationship between film thickness and surface resistivity

Surface resistivity indicates degree of difficulty of electric conduction on the surface. However, in practice, electric current flowing inside of coated film can not be neglected. Accordingly, there is a tendency that the thicker the film is, the smaller surface resistivity is.

Fig.3 shows the relationship between film thickness (dry) and surface resistivity. When the film becomes thin, the surface resistivity rises drastically.

Fig. 3. Film thickness and surface resistivityFig. 3. Film thickness and surface resistivity

3. Whiteness and conductivity

The most advantageous characteristic of ET and FT series is whiteness. In general, electroconductivity and whiteness are counteractive factors each other. ET and FT are designed with taking these balance properly into account. When practically applying the materials in coatings, whiteness and conductivity of the coatings can be varied by changing formulations. Fig.4 and 5 indicate the relationships between whiteness and conductivity in variation of PWC.

Fig. 4. Whiteness and surface resistivity (ET-500W and 600W)Fig. 4. Whiteness and surface resistivity
(ET-500W and 600W)

Fig. 5. Whiteness and surface resistivity (FT-1000 and 2000)Fig. 5. Whiteness and surface resistivity
(FT-1000 and 2000)

Fig.6. Whiteness and surface resistivity (Mixture of FT-2000 and pigmental TiO2Fig.6. Whiteness and surface resistivity
(Mixture of FT-2000 and pigmental TiO2

To top of page

Characteristics of Transparent Electro-Conductive Materials, SN series

1. Relationship between surface resistivity and content

The relationship between surface resistivity and content in thin coatings is shown in Fig. 1. Low haze, i.e. high transparency, and sufficient conductivity can be achieved for the thin coatings.

Fig. 1. Relationship between surface resistivity and content (water-borne coatings with 0.43µm thickness)Fig. 1. Relationship between surface resistivity and content (water-borne coatings with 0.43µm thickness)

* Haze values are shown in parentheses

2. Film thickness and surface resistivity

Surface resistivity represents the ability of surface electric current. However, the surface resistivity actually measured tends to decrease as the coating thickness increases due to the influence of the inner electric current. Fig.2 shows the relationship between surface resistivity and coating thickness.

Fig.2 Relationship between surface resistivity and coating thickness.Fig.2 Relationship between surface resistivity and coating thickness.

3. Transparency (Haze)

The electroconductivity and haze are affected by pigment concentration, dispersion time and coating thickness. Fig.3 to 5 show the relationships between two parameters.

Fig.3 Relationship between pigment concentration and hazeFig.3 Relationship between pigment concentration and haze

Fig.4 Relationship between dispersion time and hazeFig.4 Relationship between dispersion time and haze

Fig.5 Relationship between coating thickness and hazeFig.5 Relationship between coating thickness and haze

From the results, lower haze can be obtained by lower pigment concentration, stronger dispersion and thinner coating. However, taking the conductivity into account, total quality of the coating film will be improved by making the content higher and the thickness lower.

4. Dispersion stability

Fig.6 shows ζ potential of SN-100P. From neutral to alkaline pH, SN-100P has significantly negative ζ potential. This property is rarely seen in other oxides. Accordingly, SN-100D, which is water dispersion product of SN-100P, shows superior dispersion stability due to the strong electric repulsion. SN-100D shows excellent stability without adding dispersing agents.

Fig.6 Zeta potential of SN-100PFig.6 Zeta potential of SN-100P

5. IR-shielding ability of SN-100P

Fig.7 shows transmittance curve of SN-100P coating. Infrared rays are absorbed due to the plasmon absorption of free electrons of SN-100P.

Fig.7 IR-shielding abilityFig.7 IR-shielding ability

To top of page

Acicular Transparent Electro-conductive Materials, FS series

1. Color of the coating containing FS product

FS products are light-colored compared with SN products as seen below.

Photo: Color of the coating containing FS product

2. Surface resistivity of the coating containing FS products

The acicular FS products can achieve sufficient electroconductivity with a lower content compared with the spherical SN products

Graph: Surface resistivity of the coating containing FS products