Paper manufacturing process = finger print in paper e.g. refining, retention, sizing, filler, initial dewatering, forming, pressing, drying, drying symmetry, fabrics, etc. Paper structure Paper properties Customer demands Example (axial curl) jet-wire ratio, initial dewatering, surface sizing, drying, drying symmetry Orientation profile Twosidedness in elasticity and plastic limit bonding Paper curl Flat paper
PAPER STRUCTURE 1.FORMATION 2.ORIENTATION Fiber alignment Anisotropy in plane and in z-direction 3.MATERIAL DISTRIBUTION IN Z-DIRECTION 4.DENSITY AND IT´S Z-DIRECTIONAL DISTRIBUTION 5.POROSITY AND IT´S Z-DIRECTIONAL DISTRIBUTION Pore volume Pore size distribution 6.INTERNAL BONDING 7.INTERNAL STRESSES In-plane / anisotropy Twosidedness (z-directional), axial and small scale 8.SURFACE STRUCTURE … and OPTICAL PROPERTIES THERMAL PROPERTIES ELECTRICAL PROPERTIES
660 / 1300 = 0,51 about 50 % of paper is pores