NC State
H. Bucher. Discontinuities in the microscopic structure of wood fibres. In Fundamentals of Papermaking Fibres, Trans. of the Ist Fund. Res. Symp. Cambridge, 1957, (F. Bolam, ed.), pp 7–26, FRC, Manchester, 2018.


A discontinuous structural organisation characterises biological cells such as wood fibres. The correlation between discontinuities in the microscopic fibre structure and some physical and chemical features of the fibres are discussed. The co-axial lamellar structure, a longitudinal discontinuity, is of particular importance in fibre technology. Considering morphological phenomena during maceration of wood fibres, we came to the conclusion that a real discontinuity exists between the secondary wall and its inner layer, the so-called tertiary wall. The special morphological and individual character of the tertiary wall (S3) is demonstrated in a number of micrographs and colour slides. Information is given of the structure of the tertiary wall and the helix angles of the fibrillar pattern are indicated for 8 species of softwood. As the colour slides are not published in this paper and the number of micrographs has had to be reduced, some abridgements of the paper were necessary.

Download PDF