SIST EN ISO 19403-2:2020
(Main)Paints and varnishes - Wettability - Part 2: Determination of the surface free energy of solid surfaces by measuring the contact angle (ISO 19403-2:2017)
Paints and varnishes - Wettability - Part 2: Determination of the surface free energy of solid surfaces by measuring the contact angle (ISO 19403-2:2017)
ISO 19403-2:2017 specifies a test method to measure the contact angle for the determination of the surface free energy of a solid surface. The method can be applied for the characterization of substrates and coatings.
NOTE 1 For the determination of the surface free energy of polymers and coatings, either the method in accordance with Owens, Wendt, Rabel and Kaelble or the method in accordance with Wu is used preferably.
NOTE 2 The morphological and chemical homogeneity have an influence on the measuring results.
NOTE 3 The procedures indicated in ISO 19403-2:2017 are based on the state-of-the-art employing the drop projection method in penumbral shadow. Other methods are not excluded.
NOTE 4 Measuring the contact angle on powders is not part of ISO 19403-2:2017. For further information, see the bibliography.
Beschichtungsstoffe - Benetzbarkeit - Teil 2: Bestimmung der freien Oberflächenenergie fester Oberflächen durch Messung des Kontaktwinklels (ISO 19403-2:2017)
Peintures et vernis - Mouillabilité - Partie 2: Détermination de l'énergie libre de surface des surfaces solides par la mesure de l'angle de contact (ISO 19403-2:2017)
Le présent document spécifie une méthode d'essai permettant de mesurer l'angle de contact afin de déterminer l'énergie libre de surface d'une surface solide. Cette méthode peut être utilisée pour la caractérisation de substrats et revêtements.
NOTE 1 La détermination de l'énergie libre de surface de polymères et de revêtements se fait de préférence conformément à la méthode d'Owens, Wendt, Rabel et Kaelble ou à la méthode de Wu.
NOTE 2 L'homogénéité morphologique et chimique influe sur les résultats des mesurages.
NOTE 3 Les modes opératoires indiqués dans le présent document s'appuient sur les dernières techniques connues employant la méthode de projection de la goutte dans la pénombre. Les autres méthodes ne sont pas exclues.
NOTE 4 Le mesurage de l'angle de contact sur des poudres ne fait pas partie du présent document. Pour plus d'informations, voir la Bibliographie.
Barve in laki - Omočljivost - 2. del: Določevanje proste površinske energije površin trdnih teles z merjenjem stičnega kota (ISO 19403-2:2017)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 19403-2:2020
01-april-2020
Barve in laki - Omočljivost - 2. del: Določevanje proste površinske energije površin
trdnih teles z merjenjem stičnega kota (ISO 19403-2:2017)
Paints and varnishes - Wettability - Part 2: Determination of the surface free energy of
solid surfaces by measuring the contact angle (ISO 19403-2:2017)
Beschichtungsstoffe - Benetzbarkeit - Teil 2: Bestimmung der freien Oberflächenenergie
fester Oberflächen durch Messung des Kontaktwinklels (ISO 19403-2:2017)
Peintures et vernis - Mouillabilité - Partie 2: Détermination de l'énergie libre de surface
des surfaces solides par la mesure de l'angle de contact (ISO 19403-2:2017)
Ta slovenski standard je istoveten z: EN ISO 19403-2:2020
ICS:
87.040 Barve in laki Paints and varnishes
SIST EN ISO 19403-2:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 19403-2:2020
---------------------- Page: 2 ----------------------
SIST EN ISO 19403-2:2020
EN ISO 19403-2
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2020
EUROPÄISCHE NORM
ICS 01.040.87
English Version
Paints and varnishes - Wettability - Part 2: Determination
of the surface free energy of solid surfaces by measuring
the contact angle (ISO 19403-2:2017)
Peintures et vernis - Mouillabilité - Partie 2: Beschichtungsstoffe - Benetzbarkeit - Teil 2:
Détermination de l'énergie libre de surface des Bestimmung der freien Oberflächenenergie fester
surfaces solides par la mesure de l'angle de contact Oberflächen durch Messung des Kontaktwinkels (ISO
(ISO 19403-2:2017) 19403-2:2017)
This European Standard was approved by CEN on 4 November 2019.
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
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19403-2:2020 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 19403-2:2020
EN ISO 19403-2:2020 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 19403-2:2020
EN ISO 19403-2:2020 (E)
European foreword
The text of ISO 19403-2:2017 has been prepared by Technical Committee ISO/TC 35 "Paints and
varnishes” of the International Organization for Standardization (ISO) and has been taken over as
EN ISO 19403-2:2020 by Technical Committee CEN/TC 139 “Paints and varnishes” 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 August 2020, and conflicting national standards shall
be withdrawn at the latest by August 2020.
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.
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 19403-2:2017 has been approved by CEN as EN ISO 19403-2:2020 without any
modification.
3
---------------------- Page: 5 ----------------------
SIST EN ISO 19403-2:2020
---------------------- Page: 6 ----------------------
SIST EN ISO 19403-2:2020
INTERNATIONAL ISO
STANDARD 19403-2
First edition
2017-06
Paints and varnishes — Wettability —
Part 2:
Determination of the surface free
energy of solid surfaces by measuring
the contact angle
Peintures et vernis — Mouillabilité —
Partie 2: Détermination de l’énergie libre de surface des surfaces
solides par la mesure de l’angle de contact
Reference number
ISO 19403-2:2017(E)
©
ISO 2017
---------------------- Page: 7 ----------------------
SIST EN ISO 19403-2:2020
ISO 19403-2:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 19403-2:2020
ISO 19403-2:2017(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus and materials. 2
6 Sampling . 3
7 Procedure. 4
7.1 General for measuring on the horizontal drop . 4
7.1.1 Setting up the contact angle measuring system . 4
7.1.2 Test conditions. 4
7.1.3 Conditioning of the test panels . 4
7.2 Measurement . 4
7.2.1 General. 4
7.2.2 Static method . 4
7.2.3 Dynamic method (progressive contact angle) . 5
7.2.4 Determination of the contact angle . 6
8 Evaluation . 6
8.1 General . 6
8.2 Owens-Wendt-Rabel-Kaelble method (OWRK method) . 6
8.3 Wu method . 7
9 Precision . 8
9.1 General . 8
9.2 Repeatability limit, r . 8
9.3 Reproducibility limit, R . 8
9.4 Calculation in accordance with Owens-Wendt-Rabel-Kaelble method (OWRK method) . 8
10 Test report . 9
Annex A (informative) Notes on measuring practice .10
Bibliography .14
© ISO 2017 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 19403-2:2020
ISO 19403-2:2017(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 on 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 the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee
SC 9, General test methods for paints and varnishes.
A list of all parts in the ISO 19403 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 19403-2:2020
INTERNATIONAL STANDARD ISO 19403-2:2017(E)
Paints and varnishes — Wettability —
Part 2:
Determination of the surface free energy of solid surfaces
by measuring the contact angle
1 Scope
This document specifies a test method to measure the contact angle for the determination of the surface
free energy of a solid surface. The method can be applied for the characterization of substrates and
coatings.
NOTE 1 For the determination of the surface free energy of polymers and coatings, either the method in
accordance with Owens, Wendt, Rabel and Kaelble or the method in accordance with Wu is used preferably.
NOTE 2 The morphological and chemical homogeneity have an influence on the measuring results.
NOTE 3 The procedures indicated in this document are based on the state-of-the-art employing the drop
projection method in penumbral shadow. Other methods are not excluded.
NOTE 4 Measuring the contact angle on powders is not part of this document. For further information, see the
bibliography.
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 4618, Paints and varnishes — Terms and definitions
ISO 19403-1, Paints and varnishes — Wettability — Part 1: Terminology and general principles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 and ISO 19403-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
4 Principle
A minimum of three drops of at least two test liquids are dosed onto the flat surface of a test specimen.
For every drop, the contact angle is measured. From the averaged contact angles of every liquid, their
surface tensions, as well as their polar and dispersive fractions, the surface free energy of the solid is
calculated by means of an appropriate model, divided into the polar and dispersive fractions.
© ISO 2017 – All rights reserved 1
---------------------- Page: 11 ----------------------
SIST EN ISO 19403-2:2020
ISO 19403-2:2017(E)
5 Apparatus and materials
Ordinary laboratory apparatus, together with the following.
5.1 Contact angle measuring system.
Any state-of-the-art contact angle measuring device, preferably systems with digital image capture
and analysis for measuring the contact angle. Figure 1 shows a schematic example of a contact angle
measuring system.
Key
1 light source
2 specimen holder
3 graduaded micro syringe
4 optical system
5 screen
NOTE 1 The image capturing system is oriented in a way that the optimal image resolution ratio (ratio of
width and height) can be used.
NOTE 2 The device used can differ from the schematic diagram in regard to light path and the arrangement of
the components.
Figure 1 — Schematic diagram of a contact angle measuring system
5.2 Dosing unit.
The dosing unit makes it possible to precisely apply drops in the range of microlitres to the surface.
5.3 Test liquids.
At least two of the test liquids suggested in Table 1. The test liquids shall have at least “purity grade” for
analysis. Water shall have a surface tension of at least 71,5 mN/m.
It is recommended to test the suitability of the liquids used in accordance with ISO 19403-3 or EN 14370
prior to measuring their surface tensions. For guidance, the values from the literature for the surface
tension, σ , are indicated in Table 1. It is also possible to use an individually measured value of the
l
surface tension as reference value. According to experience, the measured value should not deviate
more than ±2 % from the value from the literature or the individually determined value.
2 © ISO 2017 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 19403-2:2020
ISO 19403-2:2017(E)
The test liquids shall not physically or chemically affect the surface. The test liquids have a maximum of
different polar and dispersive fractions of surface tension.
For at least one of the test liquids used, the polar fractions shall be larger than 0 mN/m (see Table 1).
In case only two test liquids are used, water and di-iodomethane are recommended. In case three
liquids are used, ethylene glycol should be used additionally.
In case of high viscous test liquids like glycerol and ethylene glycol, a needle with higher inner diameter
could be necessary to achieve the recommended dosing rate.
NOTE The values in Table 1 refer to 25 °C measuring temperature. For measuring under standard
atmosphere (see 7.1.2), no significant deviations can be assumed.
Table 1 — Suggested test liquids
Test liquid Surface tension Dispersive fraction Polar fraction Source
d
p
σ σ
σ
l l
l
mN/m mN/m
mN/m
Water 72,8 21,8 51,0 Reference [4]
a
Di-iodomethane 50,8 50,8 0,0 Reference [4]
1,2-ethanediol
47,7 30,9 16,8 Reference [4]
(ethylene glycol)
1,2,3-propanetriol
63,4 37,0 26,4 Reference [4]
(glycerol)
Hexadecane 27,6 27,6 0,0 Reference [4]
1- bromo-
44,6 44,6 0,0 Reference [4]
b
naphthalene
Benzyl alcohol 38,9 29,0 9,9 Reference [5]
Decalin
30,6 30,6 0,0 Reference [4]
(isomer mixture)
cis-Decalin 32,2 32,2 0,0 Reference [2]
trans-Decalin 29,9 29,9 0,0 Reference [2]
a
Di-iodomethane is relative instable, yellowing after short time by splitting-off iodine.
Di-iodomethane swells and dissolves a lot of plastics and of organic coatings.
Di-iodomethane reacts with common metals (e.g. magnesium).
b
1-bromo-naphtalene reacts with common metals (e.g. magnesium).
1-bromo-naphtalene tends to swelling and dissolving of high-molecular compounds.
6 Sampling
Take a representative specimen of the substrate to be tested. The specimens shall not be contaminated
before measuring.
Preferably, the specimen should have the minimum size of 10 cm × 10 cm.
See also Annex A.
© ISO 2017 – All rights reserved 3
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SIST EN ISO 19403-2:2020
ISO 19403-2:2017(E)
7 Procedure
7.1 General for measuring on the horizontal drop
7.1.1 Setting up the contact angle measuring system
Choose the location of the contact angle measuring system so that it is not exposed to
— vibrations,
— intense air flows (e.g. caused by air conditioning), and
— intense exposure to light from outside (e.g. windows, bright lighting).
Align the contact angle measuring system horizontally.
7.1.2 Test conditions
Carry out the test at (23 ± 2) °C and a relative humidity of (50 ± 5) % (see ISO 3270) and make sure that
all test media have this temperature.
7.1.3 Conditioning of the test panels
Condition the test panels at a temperature of (23 ± 2) °C and a relative humidity of (50 ± 5) % for a
minimum of 16 h prior to testing. Carry out the test immediately after conditioning.
7.2 Measurement
7.2.1 General
Place a preferably flat test specimen of the surface to be measured on the sample holder. Adjust the
sample holder so that the surface of the test specimen is located in the lower half of the image and that
it is horizontally aligned.
Fill the dosing system with the chosen liquid. Pay attention to fill without contamination or bubbles.
Set up an image representation that is sufficient in regard to brightness and contrast (mind the
specifications given by the manufacturer).
NOTE 1 If possible, set the light source of the contact angle measuring device so that the grey val
...
SLOVENSKI STANDARD
oSIST prEN ISO 19403-2:2019
01-julij-2019
Barve in laki - Omočljivost - 2. del: Določevanje proste površinske energije površin
trdnih teles z merjenjem stičnega kota (ISO 19403-2:2017)
Paints and varnishes - Wettability - Part 2: Determination of the surface free energy of
solid surfaces by measuring the contact angle (ISO 19403-2:2017)
Beschichtungsstoffe - Benetzbarkeit - Teil 2: Bestimmung der freien Oberflächenenergie
fester Oberflächen durch Messung des Kontaktwinklels (ISO 19403-2:2017)
Peintures et vernis - Mouillabilité - Partie 2: Détermination de l'énergie libre de surface
des surfaces solides par la mesure de l'angle de contact (ISO 19403-2:2017)
Ta slovenski standard je istoveten z: prEN ISO 19403-2
ICS:
87.040 Barve in laki Paints and varnishes
oSIST prEN ISO 19403-2:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 19403-2:2019
---------------------- Page: 2 ----------------------
oSIST prEN ISO 19403-2:2019
INTERNATIONAL ISO
STANDARD 19403-2
First edition
2017-06
Paints and varnishes — Wettability —
Part 2:
Determination of the surface free
energy of solid surfaces by measuring
the contact angle
Peintures et vernis — Mouillabilité —
Partie 2: Détermination de l’énergie libre de surface des surfaces
solides par la mesure de l’angle de contact
Reference number
ISO 19403-2:2017(E)
©
ISO 2017
---------------------- Page: 3 ----------------------
oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus and materials. 2
6 Sampling . 3
7 Procedure. 4
7.1 General for measuring on the horizontal drop . 4
7.1.1 Setting up the contact angle measuring system . 4
7.1.2 Test conditions. 4
7.1.3 Conditioning of the test panels . 4
7.2 Measurement . 4
7.2.1 General. 4
7.2.2 Static method . 4
7.2.3 Dynamic method (progressive contact angle) . 5
7.2.4 Determination of the contact angle . 6
8 Evaluation . 6
8.1 General . 6
8.2 Owens-Wendt-Rabel-Kaelble method (OWRK method) . 6
8.3 Wu method . 7
9 Precision . 8
9.1 General . 8
9.2 Repeatability limit, r . 8
9.3 Reproducibility limit, R . 8
9.4 Calculation in accordance with Owens-Wendt-Rabel-Kaelble method (OWRK method) . 8
10 Test report . 9
Annex A (informative) Notes on measuring practice .10
Bibliography .14
© ISO 2017 – All rights reserved iii
---------------------- Page: 5 ----------------------
oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(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 on 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 the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee
SC 9, General test methods for paints and varnishes.
A list of all parts in the ISO 19403 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved
---------------------- Page: 6 ----------------------
oSIST prEN ISO 19403-2:2019
INTERNATIONAL STANDARD ISO 19403-2:2017(E)
Paints and varnishes — Wettability —
Part 2:
Determination of the surface free energy of solid surfaces
by measuring the contact angle
1 Scope
This document specifies a test method to measure the contact angle for the determination of the surface
free energy of a solid surface. The method can be applied for the characterization of substrates and
coatings.
NOTE 1 For the determination of the surface free energy of polymers and coatings, either the method in
accordance with Owens, Wendt, Rabel and Kaelble or the method in accordance with Wu is used preferably.
NOTE 2 The morphological and chemical homogeneity have an influence on the measuring results.
NOTE 3 The procedures indicated in this document are based on the state-of-the-art employing the drop
projection method in penumbral shadow. Other methods are not excluded.
NOTE 4 Measuring the contact angle on powders is not part of this document. For further information, see the
bibliography.
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 4618, Paints and varnishes — Terms and definitions
ISO 19403-1, Paints and varnishes — Wettability — Part 1: Terminology and general principles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 and ISO 19403-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
4 Principle
A minimum of three drops of at least two test liquids are dosed onto the flat surface of a test specimen.
For every drop, the contact angle is measured. From the averaged contact angles of every liquid, their
surface tensions, as well as their polar and dispersive fractions, the surface free energy of the solid is
calculated by means of an appropriate model, divided into the polar and dispersive fractions.
© ISO 2017 – All rights reserved 1
---------------------- Page: 7 ----------------------
oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(E)
5 Apparatus and materials
Ordinary laboratory apparatus, together with the following.
5.1 Contact angle measuring system.
Any state-of-the-art contact angle measuring device, preferably systems with digital image capture
and analysis for measuring the contact angle. Figure 1 shows a schematic example of a contact angle
measuring system.
Key
1 light source
2 specimen holder
3 graduaded micro syringe
4 optical system
5 screen
NOTE 1 The image capturing system is oriented in a way that the optimal image resolution ratio (ratio of
width and height) can be used.
NOTE 2 The device used can differ from the schematic diagram in regard to light path and the arrangement of
the components.
Figure 1 — Schematic diagram of a contact angle measuring system
5.2 Dosing unit.
The dosing unit makes it possible to precisely apply drops in the range of microlitres to the surface.
5.3 Test liquids.
At least two of the test liquids suggested in Table 1. The test liquids shall have at least “purity grade” for
analysis. Water shall have a surface tension of at least 71,5 mN/m.
It is recommended to test the suitability of the liquids used in accordance with ISO 19403-3 or EN 14370
prior to measuring their surface tensions. For guidance, the values from the literature for the surface
tension, σ , are indicated in Table 1. It is also possible to use an individually measured value of the
l
surface tension as reference value. According to experience, the measured value should not deviate
more than ±2 % from the value from the literature or the individually determined value.
2 © ISO 2017 – All rights reserved
---------------------- Page: 8 ----------------------
oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(E)
The test liquids shall not physically or chemically affect the surface. The test liquids have a maximum of
different polar and dispersive fractions of surface tension.
For at least one of the test liquids used, the polar fractions shall be larger than 0 mN/m (see Table 1).
In case only two test liquids are used, water and di-iodomethane are recommended. In case three
liquids are used, ethylene glycol should be used additionally.
In case of high viscous test liquids like glycerol and ethylene glycol, a needle with higher inner diameter
could be necessary to achieve the recommended dosing rate.
NOTE The values in Table 1 refer to 25 °C measuring temperature. For measuring under standard
atmosphere (see 7.1.2), no significant deviations can be assumed.
Table 1 — Suggested test liquids
Test liquid Surface tension Dispersive fraction Polar fraction Source
d
p
σ σ
σ
l l
l
mN/m mN/m
mN/m
Water 72,8 21,8 51,0 Reference [4]
a
Di-iodomethane 50,8 50,8 0,0 Reference [4]
1,2-ethanediol
47,7 30,9 16,8 Reference [4]
(ethylene glycol)
1,2,3-propanetriol
63,4 37,0 26,4 Reference [4]
(glycerol)
Hexadecane 27,6 27,6 0,0 Reference [4]
1- bromo-
44,6 44,6 0,0 Reference [4]
b
naphthalene
Benzyl alcohol 38,9 29,0 9,9 Reference [5]
Decalin
30,6 30,6 0,0 Reference [4]
(isomer mixture)
cis-Decalin 32,2 32,2 0,0 Reference [2]
trans-Decalin 29,9 29,9 0,0 Reference [2]
a
Di-iodomethane is relative instable, yellowing after short time by splitting-off iodine.
Di-iodomethane swells and dissolves a lot of plastics and of organic coatings.
Di-iodomethane reacts with common metals (e.g. magnesium).
b
1-bromo-naphtalene reacts with common metals (e.g. magnesium).
1-bromo-naphtalene tends to swelling and dissolving of high-molecular compounds.
6 Sampling
Take a representative specimen of the substrate to be tested. The specimens shall not be contaminated
before measuring.
Preferably, the specimen should have the minimum size of 10 cm × 10 cm.
See also Annex A.
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7 Procedure
7.1 General for measuring on the horizontal drop
7.1.1 Setting up the contact angle measuring system
Choose the location of the contact angle measuring system so that it is not exposed to
— vibrations,
— intense air flows (e.g. caused by air conditioning), and
— intense exposure to light from outside (e.g. windows, bright lighting).
Align the contact angle measuring system horizontally.
7.1.2 Test conditions
Carry out the test at (23 ± 2) °C and a relative humidity of (50 ± 5) % (see ISO 3270) and make sure that
all test media have this temperature.
7.1.3 Conditioning of the test panels
Condition the test panels at a temperature of (23 ± 2) °C and a relative humidity of (50 ± 5) % for a
minimum of 16 h prior to testing. Carry out the test immediately after conditioning.
7.2 Measurement
7.2.1 General
Place a preferably flat test specimen of the surface to be measured on the sample holder. Adjust the
sample holder so that the surface of the test specimen is located in the lower half of the image and that
it is horizontally aligned.
Fill the dosing system with the chosen liquid. Pay attention to fill without contamination or bubbles.
Set up an image representation that is sufficient in regard to brightness and contrast (mind the
specifications given by the manufacturer).
NOTE 1 If possible, set the light source of the contact angle measuring device so that the grey values within
the drop close to the phase interface do not exceed the value 40 (referring to 256 grey value grades) and amount
to a minimum of 170 on the outside of the drop.
NOTE 2 It can be reasonable to test the modes of operation of the optical components by means of two-
dimensional images of drops. Such reference images are commercially available.
Move the needle to the upper margin of the image and bring into focus. Set up the zoom of the contact
angle measuring device so that the width of the contour of the drop takes up two thirds of the width of
the image.
7.2.2 Static method
Position the dosing needle approximately 3 mm to 6 mm above the surface of the test specimen. Dose
the drop so that the volume of the drop is between 2 µl and 6 µl, depending on the chosen liquid (for di-
iodomethane between 1 µl and 3 µl).
Apply one drop of the test liquid to the surface (see Figure 2).
NOTE 1 The contact between the drop and the solid surface can be achieved by putting down by means of the
needle or by picking up by means of the specimen table.
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oSIST prEN ISO 19403-2:2019
ISO 19403-2:2017(E)
a) Drop on the cannula b) Transfer of the drop c) Drop on the surface
Key
1 cannula
2 test liquid
3 surface of test specimen
Figure 2 — Putting down or picking up the drop
Align the baseline so that it runs through the three-phase points of the drop.
NOTE 2 A top-view angle can be set to help find the three-phase points.
Start measuring the contact angle immediately after finishing dosing. Prior to and during measuring,
no mutual transformation of materials between the test liquid and the surface should occur.
7.2.3 Dynamic method (progressive contact angle)
Choose the distance between the dosing needle and the surface so that the influence on the expected
contour of the drop is as slight as possible.
NOTE 1 As a first guidance for the distance between the needle and the surface of the test specimen, the one-
and-a-half-times diam
...
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