BS 7463-6 is identical to ISO 9184-6. The BS 7463 series focuses on Fibre furnish analysis of paper, board and pulps. BS 7463-6 specifies a method for the determination of fibre coarseness used in the fibre furnish analysis of paper, board and pulp. Fibre coarseness is a fibre property characterizing pulp. BS 7463-6 is applicable to pulps with relatively intact fibres, such as chemical and semi-chemical pulps.
A known mass of fibres is distributed evenly over a known area. The number of fibre crossings along a line of known length is counted on a microscope slide. The fibre coarseness is obtained by calculation. The weight factor determined in accordance with BS 7463-7 used in the fibre furnish analysis of paper, board and pulp can be calculated from the fibre coarseness.
Note: BS 7463-6 does not apply to mechanical and chemimechanical pulps or highly beaten chemical or semi-chemical pulps.
BS 7463-6 on the determination of fibre coarseness is useful for:
The coarseness of fibres has an important effect on many properties of paper. Coarseness (weight per unit length) of the fibres in a pulp may be ascertained by counting the crossings of a known weight of fibres per unit area on a prepared slide over lines of known length.
BS 7463-6 provides you with the procedure to calculate fibre coarseness. For pulps of clearly defined whole fibres, the precision of the result depends both on the skills of the operator and on the number of fibres counted. Chemical softwood pulps with fibre coarseness from 0,160 mg/m to 0,190 mg/m have been analysed for the repeatability of this method at the Finish Pulp and Paper Research Institute by several operators using one instrument.
BS 7463-6 helps to demonstrate the effects of fibre coarseness on the papermaking properties of softwood pulps by calculating the fibre coarseness. Fibre coarseness determines the strength and durability of paper.
ISO 9184-6:1994