6. Apparatus
6.1 A laboratory screening device, with 0.15 or 0.10 mm slotted screen plate. 6.2 Glass-fritted filter (15 cm in diameter). 6.3 Black wet-strength filter paper (15 cm in diameter). Maximum pore size 25 microns. 6.4 Coated paper with the following specifications: size 320 mm 210 mm, plybond resistance of 2 0.5 kN/m per DIN 54516, or 5.5 1.5 kPa per TAPPI T 541 Internal Bond Strength of Paperboard (z-Direction Tensile), 70 g/m2 basis weight of wood-free sized base paper, one-side coated 50 - 55 g/m2, ISO brightness 85 3%. 6.5 A heated press or sheet making system with heated press with temperature and pressure control. The pressure should be set at 0.8 bar (11.6 psi) and temperature at 90C. 6.6 Silicon coated paper. 6.7 Water-resistant black felt pen. 6.8 Filter washing device. 6.9 Image analysis system with a minimum of optical resolution of 65 microns/pixel (400 DPI) and 256 grey levels satisfying TAPPI T 563. Speck counting starts at 100 m (0.0078 mm2) in diameter. 6.10 Standard disintegrator, as described in TAPPI T 205 Forming Handsheets for Physical Tests of Pulp, Appendix A.