EN ISO 3262-20:2021

Extenders - Specifications and methods of test - Part 20: Fumed silica (ISO 3262-20:2021)

This document specifies requirements and corresponding methods of test for fumed silica.

Füllstoffe - Anforderungen und Prüfverfahren - Teil 20: Pyrogenes Siliciumdioxid (ISO 3262-20:2021)

Dieses Dokument legt Anforderungen und die entsprechenden Prüfverfahren für pyrogenes Siliciumdioxid fest.

Matières de charge - Spécifications et méthodes d'essai - Partie 20: Silice pyrogénée (ISO 3262-20:2021)

Le présent document spécifie des exigences ainsi que les méthodes d'essai correspondantes pour la silice pyrogénée.

Polnila - Specifikacije in preskusne metode - 20. del: Pirogeni silicijev dioksid (kremenčev dim) (ISO 3262-20:2021)

General Information

• Status: Published
• Publication Date: 06-Apr-2021
• Withdrawal Date: 30-Oct-2021
• ICS: 87.060.10 - Pigments and extenders
• Technical Committee: CEN/TC 298 - Pigments and extenders
• Drafting Committee: CEN/TC 298 - Pigments and extenders
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 07-Apr-2021
• Completion Date: 07-Apr-2021
• Ref Project: SIST EN ISO 3262-20:2021 - Extenders - Specifications and methods of test - Part 20: Fumed silica (ISO 3262-20:2021)

Relations

• Replaces: EN ISO 3262-20:2000 - Extenders for paints - Specifications and methods of test - Part 20: Fumed silica (ISO 3262-20:2000)
• Effective Date: 14-Apr-2021

Overview

EN ISO 3262-20:2021 - “Extenders - Specifications and methods of test - Part 20: Fumed silica (ISO 3262-20:2021)” is the CEN-adopted ISO standard that specifies requirements and corresponding methods of test for fumed silica used as an extender/filler. Published in 2021 (second edition), this document replaces EN ISO 3262-20:2000 and was prepared by ISO/TC 256 in collaboration with CEN/TC 298.

Key topics and technical requirements

The standard defines test procedures and reporting requirements for quality assessment of fumed silica. Main technical topics include:

• Sampling and preparation of test portions to ensure representative results.
• Determination of silica content (principle, reagents, apparatus, procedure, expression of results and precision).
• Spectrometric determination of impurity oxides such as aluminium oxide (Al2O3), titanium(IV) oxide (TiO2) and iron(III) oxide (Fe2O3), including calibration, preparation of standard solutions and calculation of oxide contents.
• Carbon content measurement (combustion/analysis procedures, calibration and precision).
• Chloride content determination and reporting.
• Total loss on ignition and other typical compositional checks required for fumed silica extenders.
• Test report format and essential information to be recorded.

The 2021 revision includes editorial and technical updates such as a retitled main heading, revised carbon content and organic surface entries, changes in recommended desiccants, added examples for suitable carbon steel, and updated normative references.

Practical applications and users

This standard is intended for organizations involved in production, testing and use of fumed silica as an extender or filler in coatings and related formulations. Typical users:

• Manufacturers and suppliers of fumed silica for quality control and specification compliance.
• Analytical and QC laboratories performing compositional and impurity analyses (spectrometry, combustion, chloride tests).
• Paint, coatings and pigment formulators specifying filler performance and purity.
• Procurement and regulatory teams needing standardized test criteria and conformance evidence.

Applying EN ISO 3262-20:2021 ensures consistent quality control, comparable test data across laboratories, and clear specification language in commercial supply chains for extenders and fillers.

Related standards

• EN ISO 3262 series - other parts cover different extenders/fillers (see ISO website for full list).
• EN ISO 3262-20:2021 supersedes EN ISO 3262-20:2000.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2021
Nadomešča:
SIST EN ISO 3262-20:2001
Polnila - Specifikacije in preskusne metode - 20. del: Pirogeni silicijev dioksid
(kremenčev dim) (ISO 3262-20:2021)
Extenders - Specifications and methods of test - Part 20: Fumed silica (ISO 3262-
20:2021)
Füllstoffe für Beschichtungsstoffe - Anforderungen und Prüfverfahren - Teil 20:
Pyrogenes Siliciumdioxid (ISO 3262-20:2021)
Matières de charge - Spécifications et méthodes d'essai - Partie 20: Silice pyrogénée
(ISO 3262-20:2021)
Ta slovenski standard je istoveten z: EN ISO 3262-20:2021
ICS:
87.060.10 Pigmenti in polnila Pigments and extenders
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 3262-20
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2021
EUROPÄISCHE NORM
ICS 87.060.10 Supersedes EN ISO 3262-20:2000
English Version
Extenders - Specifications and methods of test - Part 20:
Fumed silica (ISO 3262-20:2021)
Matières de charge - Spécifications et méthodes d'essai Füllstoffe für Beschichtungsstoffe - Anforderungen und
- Partie 20: Silice pyrogénée (ISO 3262-20:2021) Prüfverfahren - Teil 20: Pyrogenes Siliciumdioxid (ISO
3262-20:2021)
This European Standard was approved by CEN on 19 March 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 3262-20:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 3262-20:2021) has been prepared by Technical Committee ISO/TC 256
"Pigments, dyestuffs and extenders" in collaboration with Technical Committee CEN/TC 298 “Pigments
and extenders” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by October 2021, and conflicting national standards shall
be withdrawn at the latest by October 2021.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 3262-20:2000.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 3262-20:2021 has been approved by CEN as EN ISO 3262-20:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 3262-20
Second edition
2021-03
Extenders — Specifications and
methods of test —
Part 20:
Fumed silica
Matières de charge — Spécifications et méthodes d'essai —
Partie 20: Silice pyrogénée
Reference number
ISO 3262-20:2021(E)
©
ISO 2021
ISO 3262-20:2021(E)
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

ISO 3262-20:2021(E)
Contents  Page
Foreword .v
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Requirements and test methods . 2
5  Sampling . 2
6  Determination of silica content . 2
6.1 Principle . 2
6.2 Reagents. 3
6.3 Apparatus . 3
6.4 Procedure . 3
6.4.1 Number of determinations. 3
6.4.2 Test portion . 3
6.4.3 Determination . 3
6.5 Expression of results . 4
6.6 Precision . 4
7  Determination of aluminium oxide, titanium (IV) oxide and iron (III) oxide
contents by spectrometry . 4
7.1 Principle . 4
7.2 Reagents and materials . 4
7.3 Apparatus . 5
7.4 Procedure . 6
7.4.1 Preparation of standard matching solutions . 6
7.4.2 Spectrometric measurement . 6
7.4.3 Calibration graph . 7
7.4.4 Preparation of the test solution . 7
7.4.5 Determination of aluminium, titanium and iron . 7
7.4.6 Determination of the total loss on ignition . 7
7.5 Expression of results . 8
7.5.1 Calculation of the concentration of each element . 8
7.5.2 Calculation of the oxide content for each element . 8
7.6 Precision . 9
8  Determination of carbon content . 9
8.1 Principle . 9
8.2 Reagents and materials . 9
8.3 Apparatus .10
8.4 Procedure .10
8.4.1 Preparation of apparatus .10
8.4.2 Calibration .10
8.4.3 Determination .10
8.5 Expression of results .10
8.6 Precision .11
9  Determination of chloride content .11
9.1 Principle .11
9.2 Reagents.11
9.3 Apparatus .11
9.4 Procedure .12
9.4.1 Number of determinations.12
9.4.2 Test portion .12
9.4.3 Determination .12
9.5 Expression of results .12
ISO 3262-20:2021(E)
9.6 Precision .13
10  Test report .13
iv © ISO 2021 – All rights reserved

ISO 3262-20:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 256, Pigments, dyestuff and extenders,
in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/
TC 298, Pigments and extenders, in accordance with the Agreement on technical cooperation between
ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 3262-20:2000), which has been
technically revised.
The main changes compared to the previous edition are as follows:
— the main title has been changed from "Extenders for paints" to "Extenders";
— in Table 1, carbon content has been revised and organic surface has been refined;
— in 6.3.4, magnesium perchlorate has been changed to an example for a desiccant;
— in 8.2.3, suitable examples for carbon steel have been added;
— the text has been editorially revised and the normative references have been updated.
A list of all parts in the ISO 3262 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
INTERNATIONAL STANDARD ISO 3262-20:2021(E)
Extenders — Specifications and methods of test —
Part 20:
Fumed silica
1  Scope
This document specifies requirements and corresponding methods of test for fumed silica.
2  Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 787-2, General methods of test for pigments and extenders — Part 2: Determination of matter volatile
at 105 °C
ISO 787-9, General methods of test for pigments and extenders — Part 9: Determination of pH value of an
aqueous suspension
ISO 787-11, General methods of test for pigments and extenders — Part 11: Determination of tamped
volume and apparent density after tamping
ISO 787-18, General methods of test for pigments and extenders — Part 18: Determination of residue on
sieve — Mechanical flushing procedure
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 3262-1, Extenders — Specifications and methods of test — Part 1: Introduction and general test methods
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 3819, Laboratory glassware — Beakers
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
ISO 18451-1, Pigments, dyestuffs and extenders — Terminology — Part 1: General terms
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 18451-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
fumed silica
amorphous silica produced from silicon halides by high-temperature flame hydrolysis
ISO 3262-20:2021(E)
4  Requirements and test methods
For fumed silica complying with this document, the essential requirements are specified in Table 1 and
the conditional requirements are listed in Table 2.
In order to determine the pH value in an aqueous suspension, a 1 + 1 mass fraction mixture of water
and methanol is used.
Table 1 — Essential requirements and test methods
Characteristic Unit Requirement Test method
Grade A Grade B
according to
Silica content, min. 99,8 Clause 6
Oxide content
max. 0,05
— Al O
2 3
Clause 7
% mass
— TiO max. 0,03
fraction
— Fe O max. 0,003
2 3
a b
Carbon content <0,3 ≥0,3 Clause 8
Chloride content max. 0,025 Clause 9
Organic surface treatment or
— No Yes Clause 8
surface coating
% mass
Residue on 45 µm sieve max. 0,05 Not applicable ISO 787-18
fraction
% mass
Matter volatile at 105 °C max. 3 max. 1 ISO 787-2
fraction
% mass
Loss on ignition max. 2,5 max. 10 ISO 3262-1
fraction
pH value of aqueous suspension — 3,6 to 4,5 3,4 to 8 ISO 787-9
a
The carbon content is also part of the loss on ignition.
b
Usually does not exceed 15 %.
Table 2 — Conditional requirements and test methods
Characteristic Unit Requirement Test method
Grade A Grade B
according to
Apparent density after tamping g/ml ISO 787-11
To be agreed between
To be agreed between
2 the interested parties
Specific surface area m /g
the interested parties
5  Sampling
Take a representative sample of the product to be tested according to ISO 15528.
6  Determination of silica content
6.1 Principle
A test portion is ignited, weighed and treated with sulfuric acid and hydrofluoric acid. The silicon
tetrafluoride thus formed is evaporated off and the silica content is calculated from the impurities is
not required.
2 © ISO 2021 – All rights reserved

ISO 3262-20:2021(E)
6.2  Reagents
WARNING — Hydrofluoric acid is corrosive and toxic. The related operat
...