ISO 3688:2022 PDF

Scope: This document specifies two procedures for the preparation of laboratory sheets prior to measuring optical properties. One is the preparation of pads in a Büchner funnel using a filter paper or a wire screen and the other one is the preparation of laboratory sheets in a standard sheet former (conventional or Rapid Köthen). This document is applicable to all wood pulps and to most other types of pulp. It is not applicable to pulps with very long fibres, such as those made from unshortened cotton, flax and similar materials, unless they are reduced to a suitable fibre length (about 2 mm) before performing the methods. It is not applicable to recycled pulps (see ISO 21993). It is not applicable to opacity measurements or to the determination of light scattering and absorption coefficients.

ISO 3688:2022 Referenced Document

ISO 3689 Paper and board; Determination of bursting strength after immersion in water (Revision of ISO 3689-1976)
ISO 5263-1 Pulps - Laboratory wet disintegration - Part 1: Disintegration of chemical pulps
ISO 5263-2 Pulps - Laboratory wet disintegration - Part 2: Disintegration of mechanical pulps at 20 °C
ISO 5269-1 Pulps - Preparation of laboratory sheets for physical testing - Part 1: Conventional sheet-former method
ISO 5269-2 Pulps - Preparation of laboratory sheets for physical testing - Part 2: Rapid-Köthen method
ISO 7213 Pulps — Sampling for testing

2022 ISO 3688:2022 Pulps — Preparation of laboratory sheets for the measurement of optical properties
1999 ISO 3688:1999 Pulps - Preparation of laboratory sheets for the measurement of diffuse blue reflectance factor (ISO brightness)
1980 ISO 3688:1977/Amd 1:1980 Pulps; measurement of diffuse blue reflectance factor (ISO brightness); amendment 1
1977 ISO 3688:1977 Pulps; Measurement of diffuse blue reflectance factor (ISO brightness)