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  5. Silfit Z 91

Silfit Z 91

Our premium Silfit Z 91 is derived from Sillitin Z 86 through a specialized thermal process. During this process, the crystal water in the kaolinite content is removed, resulting in the formation of new, almost amorphous mineral phases. The silica content remains stable at the applied temperature. The result: products with exceptionally high whiteness and impressive color neutrality – ideal for your application.

Product characteristics
Value
Unit
Testing method
Functionalizationuntreated
Color values L*
Color values a*
Color values b*
96.5
-0.2
1.0
according to CIELAB
Color wettedExtra white
Particle size D50
Particle size D97
2.1
9.0
µmbased on ISO 13320
Residue > 40 µm10mg/kgbased on DIN EN ISO 787 Teil 18
Volatile matter at0.2%based on DIN EN ISO 787 Teil 2
Electrical conductivity20µS/cmbased on DIN EN ISO 787 Teil 14
pH Value6.5based on DIN EN ISO 787 Teil 9
Density
Bulk density
Tamped density
2.6
0.30
0.55
g/cm³based on DIN EN ISO 787 Teil 10
based on DIN ISO 903-1976
based on DIN EN ISO 787 Teil 11
Spec. Surface area (BET)
Oil absorption
10
65
m²/g
g/100 g
based on DIN ISO 9277
based on DIN EN ISO 787 Teil 5
Hardness silica/kaolinite
Abrasivity
7/4.5
40
mgbased on Mohs
based on Einlehner
Refractive index n1.55sin α / sin β
Water solubility
Acid solubility
< 0.5
< 1
%based on DIN EN ISO 787 Teil 3
based on DIN 53770 (0,1 N HCL)
Chemical Analysis
SiO2
Al2O3
Fe2O3

86
13
< 1
%based on DIN 51001 (RFA)
Mineralogical Composition
Neuburg silica
Calcined kaolinite

60
40
%based on X-ray diffraction pattern analysis combined with Rietveld
Equilibrium moisture content at 25°C
and 50% relative humidity
and 80% relative humidity
and 90% relative humidity

0.12
0.22
0.54
%based on DIN 66138
Water absorptionnot specifiedml/gbased on Baumann
Packaging
Variant
Weight
Paper bag25 kg
EVA bag10 to 20 kg
Big bag type 1≤ 600 kg
Big bag type 2≤ 750 kg
Big bag type 3≤ 900 kg
Bulk
Documents
Document
Download
Material Specification
Silfit Z 91PDF
Safety Data Sheet
SDS Silfit Z 91 - English (GB)PDF
Technical Data Sheet
TDS Elastomers - Silfit Z 91PDF
TDS Paints and varnishes - Silfit Z 91PDF
TDS Thermoplastics - Silfit Z 91PDF
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