Table 3 Physical properties of mineral flours used for anti-blocking in polyethylene

d 50 [μm]

6

3

5

3

7.6

Hardness (Mohs)

3.5

3.5

6.5

6

6

Density [g/cm³]

3.0

3.0

2.35

2.6

2.6

Refractive index

1.57

1.57

1.48

1.52

1.53

Brightness (Y/D65)

Y = 85

Y = 89

Y = 97

Y < 90

Y < 90