Development of Karl Fischer Reagents

Substance
Sample Quantity
(g)
Measurement Value
(µg)
Chapter III: Applications - 2
17. Chemicals & Materials for Electronic Equipment and Electrical Parts
Key Points
Materials for electronic equipment and electrical parts are made of
mixed or composite materials. They vary widely in terms of both the raw
materials and their form. The methods used to measure moisture
content must be selected with reference to the characteristics of each
item. These items generally have a low moisture content and many are
insoluble in solvents. For this reason, moisture content is measured
using moisture vaporization and coulometric titration.
Chemical products such as liquid crystals, photoresists and capacitor
electrolytes can be dissolved in dehydrated solvents or electrolytes.
This means that they can be titrated directly using volumetric or
coulometric titration.
Chemical substances may be either liquid or solid. For viscous liquids,
a syringe with a 2mm diameter needle should be used.
[Examples of Measurement]
(1) Volumetric titration
Reagents used: Karl Fischer Reagent SS-Z (or SS)
Dehydrated Solvent GEX, OL II (or MS, CM) 25-50ml
Substance
Capacitor electrolyte
Liquid crystal
Photoresist
Liquid crystal
Photoresist
Dehydrated
solvents
General-use
"
Oil-type
1.0504
0.5578
Sample Quantity
(g)
0.0454
1.0998
1.0823
(2) Coulometric titration
Reagents used: Aquamicron AX (or AS) 100ml
Aquamicron CXU 5ml
196
998
Measurement Value
(mg)
3.67
0.23
3.23
Moisture Content
(%)
187ppm
0.179
Moisture Content
(%)
8.080
209ppm
0.298
165