Under normal circumstances, the blackness of carbon black is the core detection index of its product quality. A Spectrophotometer is often used to analyze its blackness. So besides the blackness detection, what other properties of carbon black can be tested?
1. Tinting strength of carbon black
①. Principle
Industrial colored reference carbon black (ITRB) or standard reference carbon black 3# (SRB3#) is mixed with zinc oxide and liquid plasticizer, and the obtained paste is ground evenly, and then coated into a film with uniform thickness, Use a reflectometer sensitive to different gray gradients to measure the reflectance of light.
Mix the samples in the same way, and measure the reflectance of the light. The coloring strength of the sample can be obtained from the ratio of the reflectance of the two lights.
②.Calculation method
Tinting strength T is measured by the ratio of the light reflectance of the standard sample to the sample, as shown in formula (1), and the value is expressed in %:
In the formula:
R------0.100 Reflectance value of 0g standard sample
S------sample reflectance value
Take the color spectrum CS-660 spectroColorimeter as an example to illustrate how to measure the tinting strength of carbon black
1. Prepare the ink slurry film of standard reference carbon black and sample carbon black according to the standard
2. Use CS-660 to measure the Y value of the standard reference carbon black, that is, the reflectance value Yt of the standard reference carbon black
3. Use CS-660 to measure the Y value of the sample carbon black, that is, the reflectance value Ys of the sample carbon black
4. Calculate the coloring strength of the sample carbon black T=Yt/Ys
2. Particle size measurement
①. Principle
The light source shines on the carbon black surface at an angle of 45°, the carbon black absorbs most of the incident light, and a small part of the incident light is reflected from the carbon black surface. The smaller the particle size of carbon black, the weaker the reflected light. The photovoltaic cell converts the light energy of the diffused light in the vertical direction into electrical energy, and the reflectance is displayed on the reflectometer, and the particle size value of carbon black is calculated from the relationship between the particle size and the reflectance.
②.Calculation method
Substitute the reflectance value of the sample carbon black into the following empirical equation to calculate the carbon black particle size (D), and the value is expressed in nanometers (nm):
In the formula:
D------carbon black particle size value, the unit is nanometer (nm);
I------reflectance value of carbon black.
Take our CS-600C as an example to explain how to measure the particle size of carbon black
1. Use CS-600C to measure the reflectance value Y of carbon black
2. Y is equal to I in the particle size formula, and the Y value is substituted into I, and the particle size of carbon black can be calculated from the particle size formula.
