Item | Unit | Test | Grade AA | Grade A | ||
Method | ||||||
Basis Weight | G/M2 | ISO 536:1995 | 230-450 | 230-450±3% | ||
Density | ≤300 G/M2 | G/M3 | ISO 534:1998 | 0.82 | 0.83 | |
>300 G/M2 | 0.8 | 0.81 | ||||
Brightness (face) | ≥ | % | ISO2470:1999 | 94 | 92 | |
Smoothness | ≥ | s | ISO5627:1995 | 200 | 150 | |
PPS Roughness | ≤ | μm | ISO8791-4:1992 | 1.8 | 2 | |
Printing Gloss | ≥ | % | GB/T 12032 | 90 | 88 | |
Oil Absorbance | % | GB/T 12911 | 15~28 | |||
(K&N Value) | ||||||
Resistance to picking | m/s | ISO 3783:1980 | 1.5 | 1.4 | ||
( Middle Viscosity) ≥ | ||||||
Cobb | face ≤ | G/M2 | ISO 535:1991 | 50 | ||
Water absorptiveness | back ≤ | 120 | ||||
Stiffness | 230 G/M2 | mN·m | ISO2493:1992 | 2.5 | 2.3 | |
CD | 250 G/M2 | 3.2 | 3 | |||
≥ | 300 G/M2 | 5.4 | 5.2 | |||
350 G/M2 | 7.9 | 7.6 | ||||
400 G/M2 | 11 | 10.6 | ||||
450 G/M2 | 15.2 | 14.5 | ||||
Dust | 0.2~1.0mm2 | each/m2 | GB/T 1541 | 10 | 12 | |
(Spot) | >1.0~2.0mm2 | 0 | 0 | |||
≤ | >2.0mm2 | 0 | 0 | |||
Moisture | ≤300 G/M2 | % | ISO 287:1991 | 7.0±1.0 | ||
>300 G/M2 | 7.5±1.0 | |||||
*Test conditions: ISO 554 - 1976 (23 ± 1 °C / 50 ± 2 %) | ||||||
*MD= Machine Direction CD= Cross Direction |