Type：

Sealing Salt

Model：

500

Property：

500 is the pale green powder containing nickel is used for 

sealing under wide range of sealing temperature and easy to

use. The sealing film quality is high without poor appearance such

as uneven dyeing or smog on the processed surface. 

Working condition：

Precautions：

1. pH of the sealing solution may be varied because of the bring-in water, acid or alkali. Decrease the pH value by addition of diluted acetic acid and increase it by diluted sodium hydroxide.
2. The sealing temperature should be controlled at 90℃or above. If the process time is too long, the Al-part will produce powder on the film. If the pH value is beyond the scope of use, the reduction of sealing ability will also produce powder.
3. Filtration with a filter resistant to acid and high temperature is recommended.

Analysis method:

1. Take 10 ml of sealing solution and add 100 ml of pure water.
2. Add 10 ml of 6N- ammonium hydroxide and 2 to 3 drops of triethanolamine.
3. Add a small amount of murexide indicator until the solution become orange.
4. Titrate with 0.01M EDTA standard solution and make the solution color from orange to purple red (A ml).

Calculation: 500 (g/L) =A×F×0.331

          F-the coefficient of 0.01M EDTA standard solution