Coil coated metals - Test methods - Part 3: Colour difference and metamerism - Instrumental comparison

This part of EN 13523 specifies procedures for determining the instrumental colour difference (CIELAB) of an organic coating on a metallic substrate.
Establishing a standard as well as the magnitude of an acceptable colour difference are not covered by this method.
Two appropriate methods are given in this part of EN 13523:
a)   instrumental colour difference measurement using a tristimulus colorimeter;
b)   instrumental colour difference measurement using a spectrophotometer or equivalent.
Care shall be taken when measuring e.g.
-   textured surfaces;
-   fluorescent coatings;
-   metameric coatings;
-   multi-coloured, pearlescent, metallic or special colour effect coatings.
In order to determine whether metamerism is present, the metamerism index is determined (see EN 13523-15) and/or a visual examination (see EN 13523-22) is performed with different artificial light sources.

Bandbeschichtete Metalle - Prüfverfahren - Teil 3: Farbabstand und Metamerie - Farbmetrischer Vergleich

Dieses Dokument legt Verfahren zur farbmetrischen Bestimmung des Farbabstandes (CIELAB) einer organischen Beschichtung auf einem metallischen Untergrund im Vergleich mit einer anderen, die als Referenz verwendet wird (üblicherweise Referenz genannt), und die Metamerie in Abhängigkeit von der Lichtart fest.
Wenn zwei Farbproben identische spektrale Reflexionskurven aufweisen, ist ihre Farbe bei jeder Lichtart unabhängig von deren spektralen Eigenschaften gleich. Dies wird „unbedingt gleich“ genannt. Es ist auch möglich, dass zwei Farbproben, die unterschiedliche spektrale Reflexionskurven aufweisen, unter einer bestimmten Lichtquelle gleich aussehen, jedoch nicht unter einer anderen Lichtquelle mit anderen spektralen Eigenschaften. Dies wird „metamer“ genannt.
Eine quantitative Beschreibung der Metamerie ist der „Metamerie-Index“.
Die Angabe des Metamerie-Index ist von begrenztem Wert, wenn E (der gemessene Farbabstand für eine bestimmte Lichtart) >0,5 ist. Der Metamerie-Index ist nicht zum Bestimmen des absoluten Farbabstands oder der Farbkonstanz einer bestimmten Probe bei Lichtartwechsel geeignet.
Der Farbabstand unter der Bezugslichtart ist durch die Farbmaßzahlen L*, a* und b* zu messen.
Von diesem Verfahren ausgeschlossen sind fluoreszierende Beschichtungen, mehrfarbige Proben, Proben mit Metallic-Beschichtungen und Proben, die Perlglanzeffekte aufweisen.
Die Festlegung einer Referenz sowie der Größenordnung eines annehmbaren Farbabstandes sind nicht Gegenstand dieses Verfahrens.
Zwei Verfahren sind in diesem Dokument angegeben:
a)   farbmetrische Messung des Farbabstandes mit einem Dreibereichs-Farbmessgerät;
b)   farbmetrische Messung des Farbabstandes mit einem Spektralphotometer oder einem gleichwertigen Gerät.
Es wird empfohlen, dass bei z. B. folgenden Messungen besonders sorgfältig gearbeitet wird:
—   strukturierte Oberflächen;
—   fluoreszierende Beschichtungen;
—   Beschichtungen mit Metamerie;
—   mehrfarbige Beschichtungen, Beschichtungen mit Perlglanzeffekt, Metallic-Beschichtungen oder Beschichtungen mit besonderem Farbeffekt.

Tôles prélaquées - Méthodes d'essai - Partie 3 : Différence de couleur et métamérisme - Comparaison au moyen d'instruments

Le présent document décrit les modes opératoires permettant de déterminer, au moyen d’instruments, la différence de couleur (CIELAB) d’un revêtement organique sur un subjectile métallique par rapport à un autre revêtement utilisé comme référence (généralement appelé « référence »), ainsi que le métamérisme dépendant de l’illuminant.
Lorsque deux éprouvettes de couleur ont des courbes de réflexion spectrale identiques, les couleurs correspondent quel que soit l’illuminant et ses caractéristiques spectrales ; il s’agit d’un « appariement spectral ». Il se peut aussi que deux éprouvettes de couleur n’ayant pas la même courbe de réflexion spectrale présentent la même couleur sous une source lumineuse donnée, mais pas sous une autre source lumineuse de caractéristiques spectrales différentes ; il s’agit alors d’un « appariement métamérique ».
« L’indice de métamérisme » constitue une description quantitative du métamérisme.
L’indice de métamérisme a une valeur limitée lorsque ΔE (différence de couleur mesurée par des instruments pour un illuminant donné) est > 0,5. L’indice de métamérisme ne permet pas de déterminer la différence de couleur absolue ou la constance de couleur d’une éprouvette donnée si l’illuminant change.
La différence de couleur sous l’illuminant de référence doit être mesurée en coordonnées chromatiques L*, a* et b*.
Cette méthode ne s’applique pas aux revêtements organiques fluorescents et/ou multicolores, nacrés ou métalliques.
Cette méthode n’a pas pour objet d’établir une référence ou de déterminer l’amplitude d’une différence de couleur acceptable.
Deux méthodes sont décrites dans le présent document :
a)   le mesurage de la différence de couleur au moyen d’un colorimètre trichromatique ;
b)   le mesurage de la différence de couleur au moyen d’un spectrophotomètre ou d’un instrument équivalent.
Il est conseillé de prendre des précautions, par exemple lors du mesurage de :
—   surfaces texturées ;
—   revêtements fluorescents ;
—   revêtements métamères ;
—   revêtements multicolores, nacrés, métalliques ou à effet de couleur spécial.

Prevlečene kovine, ki se navijajo - Preskusne metode - 3. del: Barvna razlika in metamerija - Primerjava z merilnim instrumentom

General Information

Status
Published
Public Enquiry End Date
02-Dec-2020
Publication Date
08-Nov-2021
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
22-Oct-2021
Due Date
27-Dec-2021
Completion Date
09-Nov-2021

Relations

Buy Standard

Standard
SIST EN 13523-3:2021
English language
11 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day
Draft
oSIST prEN 13523-3:2020
English language
11 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 13523-3:2021
01-december-2021
Nadomešča:
SIST EN 13523-15:2015
SIST EN 13523-3:2014
Prevlečene kovine, ki se navijajo - Preskusne metode - 3. del: Barvna razlika in
metamerija - Primerjava z merilnim instrumentom
Coil coated metals - Test methods - Part 3: Colour difference and metamerism -
Instrumental comparison
Bandbeschichtete Metalle - Prüfverfahren - Teil 3: Farbabstand und Metamerie -
Farbmetrischer Vergleich

Tôles prélaquées - Méthodes d'essai - Partie 3 : Différence de couleur et métamérisme -

Comparaison au moyen d'instruments
Ta slovenski standard je istoveten z: EN 13523-3:2021
ICS:
17.180.20 Barve in merjenje svetlobe Colours and measurement of
light
25.220.60 Organske prevleke Organic coatings
SIST EN 13523-3:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 13523-3:2021
---------------------- Page: 2 ----------------------
SIST EN 13523-3:2021
EN 13523-3
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2021
EUROPÄISCHE NORM
ICS 25.220.60 Supersedes EN 13523-3:2014, EN 13523-15:2015
English Version
Coil coated metals - Test methods - Part 3: Colour
difference and metamerism - Instrumental comparison

Tôles prélaquées - Méthodes d'essai - Partie 3 : Bandbeschichtete Metalle - Prüfverfahren - Teil 3:

Différence de couleur et métamérisme - Comparaison Farbabstand und Metamerie - Farbmetrischer

au moyen d'instruments Vergleich
This European Standard was approved by CEN on 16 August 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 13523-3:2021 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN 13523-3:2021
EN 13523-3:2021 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 6

4 Principle ............................................................................................................................................................. 6

4.1 Colour difference ............................................................................................................................................. 6

4.2 Metamerism index .......................................................................................................................................... 7

5 Apparatus ........................................................................................................................................................... 7

6 Sampling ............................................................................................................................................................. 7

7 Test specimens ................................................................................................................................................. 7

8 Procedure........................................................................................................................................................... 7

8.1 Calibration ......................................................................................................................................................... 7

8.2 Measurement .................................................................................................................................................... 7

9 Expression of results ...................................................................................................................................... 8

10 Accuracy ............................................................................................................................................................. 9

11 Test report ...................................................................................................................................................... 10

Bibliography ................................................................................................................................................................. 11

---------------------- Page: 4 ----------------------
SIST EN 13523-3:2021
EN 13523-3:2021 (E)
European foreword

This document (EN 13523-3:2021) has been prepared 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 April 2022, and conflicting national standards shall be

withdrawn at the latest by April 2022.

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 13523-3:2014 and EN 13523-15:2015.
The main changes are:
a) the contents of EN 13523-3:2014 and EN 13523-15:2015 have been merged;
b) the definition for metamerism index has been added (3.4);
c) the list of the existing parts of EN 13523 has been updated;

d) the text has been editorially revised and the normative references have been updated.

The EN 13523 series, Coil coated metals — Test methods, consists of the following parts:

— Part 0: General introduction
— Part 1: Film thickness
— Part 2: Gloss
— Part 3: Colour difference and metamerism — Instrumental comparison
— Part 4: Pencil hardness
— Part 5: Resistance to rapid deformation (impact test)
— Part 6: Adhesion after indentation (cupping test)
— Part 7: Resistance to cracking on bending (T-bend test)
— Part 8: Resistance to salt spray (fog)
— Part 9: Resistance to water immersion
— Part 10: Resistance to fluorescent UV radiation and water condensation
— Part 11: Resistance to solvents (rubbing test)
— Part 12: Resistance to scratching
— Part 13: Resistance to accelerated ageing by the use of heat
---------------------- Page: 5 ----------------------
SIST EN 13523-3:2021
EN 13523-3:2021 (E)
— Part 14: Chalking (Helmen method)
— Part 16: Resistance to abrasion
— Part 17: Adhesion of strippable films
— Part 18: Resistance to staining
— Part 19: Panel design and method of atmospheric exposure testing
— Part 20: Foam adhesion
— Part 21: Evaluation of outdoor exposed panels
— Part 22: Colour difference — Visual comparison
— Part 23: Resistance to humid atmospheres containing sulfur dioxide
— Part 24: Resistance to blocking and pressure marking
— Part 25: Resistance to humidity
— Part 26: Resistance to condensation of water
— Part 27: Resistance to humid poultice (Cataplasm test)
— Part 29: Resistance to environmental soiling (Dirt pick-up and striping)

Any feedback and questions on this document should be directed to the users’ national standards body.

A complete listing of these bodies can be found on the CEN website.

According to the CEN-CENELEC Internal Regulations, the national standards organisations 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.
---------------------- Page: 6 ----------------------
SIST EN 13523-3:2021
EN 13523-3:2021 (E)
1 Scope

This document specifies procedures for determining the instrumental colour difference (CIELAB) of an

organic coating on a metallic substrate compared to another one used as a reference (usually called

reference) and the metamerism depending on the illuminant.

When two colour specimens have identical spectral reflectance curves, they are matching under any

illuminant irrespective of its spectral characteristics. This is termed a “spectral match”. It is also possible

for two colour specimens having different spectral reflectance curves to match visually under a given

light source but not to match under another light source with different spectral characteristics; such

matches are termed “metameric”.
One quantitative description of metamerism is the so-called “metamerism index”.

Information on the metamerism index is of limited value where ΔE (instrumental colour difference for a

given illuminant) is > 0,5. The metamerism index is not suited for determining the absolute colour

difference or colour consistency of a given specimen at change of illuminant.

The colour difference under the reference illuminant is to be measured in colour coordinates L*, a* and

b*.

Excluded from this method are organic coatings producing fluorescence and/or which are multicoloured,

pearlescent or metallic.

Establishing a reference as well as the magnitude of an acceptable colour difference are not covered by

this method.
Two m
...

SLOVENSKI STANDARD
oSIST prEN 13523-3:2020
01-november-2020
Prevlečene kovine, ki se navijajo - Preskusne metode - 3. del: Barvna razlika -
Primerjava z merilnim instrumentom

Coil coated metals - Test methods - Part 3: Colour difference - Instrumental comparison

Bandbeschichtete Metalle - Prüfverfahren - Teil 3: Farbabstand - Farbmetrischer
Vergleich

Tôles prélaquées - Méthodes d'essai - Partie 3 : Différence de couleur - Comparaison au

moyen d'instruments
Ta slovenski standard je istoveten z: prEN 13523-3
ICS:
17.180.20 Barve in merjenje svetlobe Colours and measurement of
light
25.220.60 Organske prevleke Organic coatings
oSIST prEN 13523-3:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN 13523-3:2020
---------------------- Page: 2 ----------------------
oSIST prEN 13523-3:2020
DRAFT
EUROPEAN STANDARD
prEN 13523-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2020
ICS 25.220.60 Will supersede EN 13523-3:2014
English Version
Coil coated metals - Test methods - Part 3: Colour
difference - Instrumental comparison

Tôles prélaquées - Méthodes d'essai - Partie 3 : Bandbeschichtete Metalle - Prüfverfahren - Teil 3:

Différence de couleur - Comparaison au moyen Farbabstand - Farbmetrischer Vergleich

d'instruments

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 139.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
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. prEN 13523-3:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
oSIST prEN 13523-3:2020
prEN 13523-3:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 6

4 Principle ............................................................................................................................................................. 6

4.1 Colour difference ............................................................................................................................................. 6

4.2 Metamerism Index .......................................................................................................................................... 7

5 Apparatus ........................................................................................................................................................... 7

6 Sampling ............................................................................................................................................................. 7

7 Test specimens ................................................................................................................................................. 7

8 Procedure........................................................................................................................................................... 7

8.1 Calibration ......................................................................................................................................................... 7

8.2 Measurement .................................................................................................................................................... 7

9 Expression of results ...................................................................................................................................... 8

10 Accuracy ............................................................................................................................................................. 9

11 Test report ...................................................................................................................................................... 10

Bibliography ................................................................................................................................................................. 11

---------------------- Page: 4 ----------------------
oSIST prEN 13523-3:2020
prEN 13523-3:2020 (E)
European foreword

This document (prEN 13523-3:2020) has been prepared by Technical Committee CEN/TC 139 “Paints

and varnishes”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 13523-3:2014 and EN 13523-15:2015.
The main changes are:
a) the contents of EN 13523-3:2014 and EN 13523-15:2015 have been merged;
b) the definition for metamerism index has been added (3.4);
c) the list of the existing parts of EN 13523 has been updated;

d) the text has been editorially revised and the normative references have been updated.

The EN 13523 series, Coil coated metals — Test methods, consists of the following parts:

— Part 0: General introduction
— Part 1: Film thickness
— Part 2: Gloss
— Part 3: Colour difference and metamerism — Instrumental comparison
— Part 4: Pencil hardness
— Part 5: Resistance to rapid deformation (impact test)
— Part 6: Adhesion after indentation (cupping test)
— Part 7: Resistance to cracking on bending (T-bend test)
— Part 8: Resistance to salt spray (fog)
— Part 9: Resistance to water immersion
— Part 10: Resistance to fluorescent UV radiation and water condensation
— Part 11: Resistance to solvents (rubbing test)
— Part 12: Resistance to scratching
— Part 13: Resistance to accelerated ageing by the use of heat
— Part 14: Chalking (Helmen method)
— Part 16: Resistance to abrasion
---------------------- Page: 5 ----------------------
oSIST prEN 13523-3:2020
prEN 13523-3:2020 (E)
— Part 17: Adhesion of strippable films
— Part 18: Resistance to staining
— Part 19: Panel design and method of atmospheric exposure testing
— Part 20: Foam adhesion
— Part 21: Evaluation of outdoor exposed panels
— Part 22: Colour difference — Visual comparison
— Part 23: Resistance to humid atmospheres containing sulfur dioxide
— Part 24: Resistance to blocking and pressure marking
— Part 25: Resistance to humidity
— Part 26: Resistance to condensation of water
— Part 27: Resistance to humid poultice (Cataplasm test)
— Part 29: Resistance to environmental soiling (Dirt pick-up and striping)
---------------------- Page: 6 ----------------------
oSIST prEN 13523-3:2020
prEN 13523-3:2020 (E)
1 Scope

This document specifies procedures for determining the instrumental colour difference (CIELAB) of an

organic coating on a metallic substrate compared to another one used as a reference (usually called

reference) and the metamerism depending on the illuminant.

When two colour specimens have identical spectral reflectance curves, they are matching under any

illuminant irrespective of its spectral characteristics. This is termed a “spectral match”. It is also

possible for two colour specimens having different spectral reflectance curves to match visually under a

given light source but not to match under another light source with different spectral characteristics;

such matches are termed “metameric”.
One quantitative description of metamerism is the so-called “metamerism index”.

Information on the metamerism index is of limited value where ΔE (instrumental colour difference for a

given illuminant) is > 0,5. The metamerism index is not suited for determining the absolute colour

difference or colour consistency of a given specimen at change of illuminant.

The colour difference under the reference illuminant is to be measured in colour coordinates L*, a* and

b*.

Excluded from this method are organic coatings producing fluorescence and/or which are

multicoloured, pearlescent or metallic.

Establishing a reference as well as the magnitude of an acceptable colour difference are not covered by

this method.
Two methods are given in this document:
a) instrumental colour difference measurement using a tristimulus colourimeter;

b) instrumental colour difference measurement using a spectrophotometer or equivalent.

Care should be taken when measuring e.g.
— textured surfaces;
— fluorescent coatings;
— metameric coatings;
— multi-coloured, pearlescent, metallic or special colour effect coatings.
2 Normative references
The following documents are referred to in the text in such a way t
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.