A. Cochaux et al., FUNDAMENTAL-STUDY OF TEAR RESISTANCE OF P ULP AND PAPER .2. RESISTANCE TO TEARING AS FUNCTION OF MORPHOLOGICAL PROPERTIES, Cellulose Chemistry and Technology, 29(2), 1995, pp. 215-229
The tear index essentially depends on the transformation of weak point
s into dislocation areas. There are two kinds of weak points. The firs
t one results from the presence of springwood fibre bordered pits. The
second one is the accumulation of amorphous cellulose in a cross sect
ion of the fibre cell well. When weak points are not transformed into
dislocation areas, a good tear index may be obtained. Flexibility is a
nother important factor for paper physical properties, since fibre def
ormations are allowed, which produces an increase of the interfibre bo
nding and the bulk of paper.