GB/T 22899.2-2008Paper and board -- Measurement of hygro-expansivity -- Part 2: Hygro-expansivity up to a maximum relative humidity of 86% (English PDF)

Foreword

GB/T 22899 "Paper and board Determination of wet expansion" is divided into two parts.

--- Part 1. Maximum relative humidity 68% expansion to wet process;

--- Part 2. Maximum relative humidity 86% to wet expansion process.

This is Part 2 GB/T 22899 of.

The partial modification of the use of ISO 8226-2:1990 "Paper and cardboard wet expansion Part 2. The maximum relative humidity is increased 86% of the wet expansion process "(in English).

This part of ISO 8226-2:1990 as compared to the main differences are as follows.

--- International Standard ISO document standard will be referenced in the normative references converted to its corresponding national standard, GB/T 450 Paper and cardboard to take samples and specimens to the vertical and horizontal, positive and negative determination (GB/T 450-2008, ISO 186:2002, MOD);

--- International Standard ISO document standard will be referenced in the normative references converted to its corresponding national standard, GB/T 451.2 Paper and cardboard quantitative determination (GB/T 451.2-2002, eqv ISO 536:1995);

--- International Standard ISO document standard will be referenced in the normative references converted to its corresponding national standard, GB/T 10739 paper, paperboard and pulp sample processing and testing standard atmospheric conditions (GB/T 10739-2002, eqv ISO 187:1990);

--- International Standard ISO document standard will be referenced in the normative references converted to its corresponding national standard, Determination of GB/T 22899.1 wet expansion of paper and cardboard - Part 1. The maximum relative humidity of 68% to the wet process Expansion (GB/T 22899.1-2008, ISO 8226-1:1994, MOD).

Appendix A of this section is an informative annex.

This part is proposed by the China National Light Industry Council.

This part of the National Standardization Technical Committee under the jurisdiction of the paper industry.

This section drafted by. China Pulp and Paper Research Institute, the national paper quality supervision and inspection center, China Paper Association Professional Committee of Standardization Members will.

1 Scope

This section GB/T 22899 specifies the method of determining the relative humidity of paper and cardboard from (33 ± 2)% ~ under (84 ± 2)% balance Methods of moisture expansion.

The purpose of this section is to reveal the use of paper and paperboard performance at high relative humidity, it can also be used to determine the short time during the printing process Ultra-moisturizing effect on the paper.

This section applies to ordinary paper and cardboard.

This section does not apply to the crepe paper and corrugated cardboard.

2 Normative references

The following documents contain provisions which, through reference GB/T 22899 in this section constitute provisions of this section. For dated reference documents Member, all subsequent amendments (not including errata content) or revisions do not apply to this section, however, encouraged to reach under this section Parties to research agreement to use the latest versions of these documents. For undated reference documents, the latest versions apply to this section.

GB/T 450 and take samples to an aspect of paper and paperboard samples, positive and negative determination (GB/T 450-2008, ISO 186.

2002, MOD)

GB/T 451.2 Paper and paperboard quantitative determination (GB/T 451.2-2002, eqv ISO 536:1995) GB/T 10739 paper, paperboard and pulp sample processing and testing standard atmospheric conditions (GB/T 10739-2002, eqv ISO 187.

1990)

Determination of GB/T 22899.1 wet expansion of paper and cardboard - Part 1. The maximum relative humidity to 68% moisture expansion process Rate (GB/T 22899.1-2008, ISO 8226-1:1994, MOD)

3 Terms and Definitions

The following terms and definitions apply to this part of the GB/T 22899 of.

Known length of paper or paperboard, balance and relative humidity from a lower value to a predetermined higher value during a predetermined length of its occurrence the change.

Note. The sample is considered contraction absorbent expansion is negative.

Principle 4

To ensure that all samples were tested from a humidity level similar to the initial relative humidity, this section contains a pre at low relative humidity Processing step.

At (23 ± 1) °C, 0 load and (22 ± 3)% relative humidity, temperature and humidity conditions of the sample pre-treatment. Then (33 ± 2)% and Under (84 ± 2)% relative humidity, the sample to be appropriate and quantitative load, measuring the change in length of the specimen between two relative humidity.