ISO 1762-2019 PDF

Full title and description

St ISO 1762-2019 — Paper, board, pulps and cellulose nanomaterials — Determination of residue (ash content) on ignition at 525 °C. This international standard specifies a laboratory procedure to determine the residue (ash) remaining after ignition of paper, board, pulps and cellulose‑based nanomaterials at 525 °C and provides guidance on sampling, sample preparation, apparatus and expression of results.

Abstract

ISO 1762:2019 describes a quantitative gravimetric method for measuring residue (ash content) by ignition at 525 °C (±25 °C). It covers normal paper, board and pulps and extends the method to cellulose nanomaterials with guidance for sample drying and handling to achieve reliable results and a target measurement precision of about 0.01 % (where practicable).

General information

• Status: Published (International Standard).
• Publication date: July 2019.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 85.040 (Paper, board and pulps).
• Edition / version: 4th edition (2019).
• Number of pages: 9 pages.

Scope

The standard applies to the determination of residue (ash content) on ignition at 525 °C for all types of paper, board and pulps and is extended to cellulose nanomaterials (defined as cellulose nano‑objects with external dimensions approximately in the 1–100 nm range). It specifies sample mass, drying and pre‑treatment recommendations, and notes how results should be reported (including reporting on a dry basis). The method is distinct from the procedure for ash determination at higher temperatures (e.g. 900 °C described in related standards).

Key topics and requirements

• Ash determination by ignition at 525 °C ± 25 °C (muffle furnace recommended).
• Measurement precision target of about 0.01 % where achievable; procedures to improve precision for low‑ash samples.
• Minimum test specimen mass on a dry basis (typical guidance: at least 1 g); residue recommendations (ideally ≥ 10 mg, preferably > 20 mg) and procedures for multiple aliquots if residue is very low.
• Apparatus: suitable muffle furnace, heat‑resistant crucibles (platinum recommended for very low residues), and an analytical balance with adequate readability.
• Separate determination or correction for moisture/dry matter (referencing the appropriate ISO moisture/dry‑matter methods) and clear expression of results on a dry basis.
• Additional sample preparation and drying guidance for cellulose nanomaterials (e.g., drying or freeze‑drying of suspensions and careful homogenization before subsampling).

Typical use and users

Routine testing and quality control laboratories in the pulp, paper and packaging industries; research laboratories working with cellulosic nanomaterials; producers and converters of paper and board verifying mineral/ash content; suppliers and purchasers specifying material composition and compliance; accreditation bodies and test houses performing comparative testing.

Related standards

Standards referenced or related to ISO 1762:2019 include methods for ash determination at other temperatures (for example methods that describe ignition at 900 °C), ISO standards covering sampling of paper and pulp, and ISO methods for moisture/dry‑matter determination that are used to report ash on a dry basis. ISO/TC 6 (Papers, board and pulps) is the technical committee responsible for the document.

Keywords

ash content, residue on ignition, paper, board, pulp, cellulose nanomaterials, muffle furnace, crucible, analytical balance, dry basis, ISO 1762

FAQ

Q: What is this standard?

A: ISO 1762:2019 is an international standard that defines a laboratory method for determining the residue (ash) remaining after ignition of paper, board, pulps and cellulose nanomaterials at 525 °C.

Q: What does it cover?

A: It covers the test procedure (ignition at 525 °C ± 25 °C), sample preparation and drying guidance (including special guidance for cellulose nanomaterials), apparatus and reporting requirements, and gives precision/accuracy guidance for routine use.

Q: Who typically uses it?

A: Analytical and quality control laboratories in the pulp and paper industry, research labs working with cellulosic nanomaterials, material suppliers and purchasers, and test houses performing standardized ash measurements.

Q: Is it current or superseded?

A: ISO 1762:2019 is the 4th edition (published July 2019) and it replaced the 2015 edition; ISO standards are normally reviewed on a five‑year cycle and this edition is the current published version as of its 2019 publication.

Q: Is it part of a series?

A: It is one of the ISO test methods addressing ash/residue and related properties of paper, board and pulps; related ISO documents address similar determinations at different temperatures and complementary properties such as moisture/dry‑matter and sampling standards for paper and pulps.

Q: What are the key keywords?

A: Ash content; residue on ignition; paper; board; pulp; cellulose nanomaterials; 525 °C; muffle furnace; analytical balance; dry basis.