SIST EN 646:2019

Paper and board intended to come into contact with foodstuffs - Determination of colour fastness of dyed paper and board

This document describes procedures for the testing of dyed paper and board intended to come into contact with foodstuffs. Some procedures depending on the foreseeable use of the material are given.
Visual evaluation against a grey scale provides grading of the bleeding.
For samples having significant different sides, a migration can occur from one glass fibre to the other and could lead to wrong interpretation of the fastness of one side. It is advisable to check these samples using large sampling procedure to prevent cross contamination of the glass fibre during the migration procedure. The procedure is described in Annex A. If lower limit of detection is required, this procedure could also be used.

Papier und Pappe vorgesehen für den Kontakt mit Lebensmitteln - Bestimmung der Farbechtheit von gefärbtem Papier und Pappe

Dieses Dokument legt ein Verfahren zur Prüfung von gefärbtem Papier und Pappe, die für den Kontakt mit Lebensmitteln bestimmt sind, fest. Es werden verschiedene Varianten angegeben, je nach vorher¬sehbarer Nutzung des vorhandenen Werkstoffs.
Die visuelle Bewertung gegen einen Graumaßstab gibt Abstufungen beim Ausbluten vor.
Bei Proben mit wesentlich unterschiedlichen Seiten kann es zu einer Migration von einer Glasfaser zur anderen kommen, was wiederum zur falschen Interpretation der Farbechtheit auf einer Seite führen könnte. Es ist empfehlenswert, diese Proben im großen Probenahmeverfahren zu prüfen, um eine Querkontamination der Glasfasern während des Migrationsvorgangs zu vermeiden. Das Verfahren ist in Anhang A beschrieben. Wenn niedrigere Nachweisgrenzen gefordert sind, könnte dieses Verfahren ebenfalls zur Anwendung kommen.

Papiers et cartons destinés à entrer en contact avec les denrées alimentaires - Détermination de la solidité de la couleur des papiers et cartons colorés

Le présent document décrit les modes opératoires d’essai pour papiers et cartons colorés destinés à entrer en contact avec les denrées alimentaires. Plusieurs modes opératoires selon l’utilisation prévisible du matériau sont décrits.
L’examen visuel par rapport à une échelle de gris permet un classement du dégorgement.
Pour les échantillons dont les faces sont sensiblement différentes, une migration peut se produire d’une fibre de verre à l’autre et peut conduire à une mauvaise interprétation de la solidité d’une face. Il est recommandé de vérifier ces échantillons à l’aide d’un mode opératoire d’échantillonnage utilisant des échantillons de grande taille afin d’empêcher la contamination croisée de la fibre de verre au cours de la procédure de migration. Le mode opératoire est décrit à l’Annexe A. Si une limite de détection inférieure est requise, ce mode opératoire peut également être utilisé.

Papir, karton in lepenka, namenjeni za stik z živili - Ugotavljanje obstojnosti barve v obarvanem papirju, kartonu in lepenki

Ta dokument opisuje postopke za preskušanje barvanega papirja in kartona, namenjenega za neposreden stik z živili. Podani so nekateri postopki, odvisni od predvidene uporabe materiala. Vizualna ocena na lestvici sivih tonov omogoča razvrščanje izločljivosti. OPOMBA: Pri vzorcih, katerih strani se precej razlikujejo, lahko pride do prehajanja iz enega steklenega vlakna v drugega, kar lahko privede do napačnega prepoznavanja obstojnosti ene strani. Te vzorce je treba pregledati s postopkom velikega vzorčenja, da se prepreči navzkrižna kontaminacija steklenih vlaken med postopkom prehajanja. Postopek je opisan v dodatku A. Če je potrebna spodnja meja zaznavanja, se lahko uporabi tudi ta postopek.

General Information

• Status: Published
• Public Enquiry End Date: 19-Apr-2017
• Publication Date: 10-Dec-2018
• ICS: 67.250 - Materials and articles in contact with foodstuffs
• ICS: 85.060 - Paper and board
• Technical Committee: VPK - Pulp, paper, board and products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 04-Dec-2018
• Due Date: 08-Feb-2019
• Completion Date: 11-Dec-2018
• Ref Project: EN 646:2018 - Paper and board intended to come into contact with foodstuffs - Determination of colour fastness of dyed paper and board

Relations

• Replaces: SIST EN 646:2006 - Paper and board intended to come into contact with foodstuffs - Determination of colour fastness of dyed paper and board
• Effective Date: 01-Jan-2019

Overview

SIST EN 646:2019 is a European standard developed by CEN that specifies the procedures for determining the colour fastness of dyed paper and board intended for direct contact with foodstuffs. This standard ensures that coloured food packaging materials do not transfer dyes or stains during use, safeguarding food safety and consumer health. The document replaces the previous EN 646:2006 and includes updated test conditions, procedures, and evaluation criteria reflecting current industry needs.

Key features include:

• Testing dyed paper and board materials for colour bleeding.
• Use of visual grading against a grey scale for staining evaluation.
• Special procedures for samples with significantly different sides to avoid cross-contamination.
• Defined test fluids and contact conditions simulating real-world food packaging scenarios.

Key Topics

• Scope and Purpose
  SIST EN 646:2019 applies to dyed papers and boards that come into contact with food, addressing both long-term and short-term contact conditions. It provides methods tailored to different foreseeable uses of the packaging material.

• Test Principle
  The testing involves placing the dyed paper or board between layers of unstained glass fibre papers saturated in specific test fluids. After exposure under controlled time, temperature, and pressure, the transfer of colour to glass fibre papers is visually assessed using an EN 20105-A03 grey scale.

• Materials and Reagents
  Essential materials include unstained glass fibre papers with defined properties (grammage, pH, absence of cellulose), glass plates, polyethylene film, and specific test fluids such as distilled water, acetic acid solution, alkaline salt solution, and vegetable oil compliant with EU food contact regulations.

• Test Procedures
  Four key procedures simulate contact durations and conditions:

  • Procedure A: Long duration (24 hours at 23°C).
  • Procedure B: Medium duration (4 hours at 23°C).
  • Procedure C: Short duration (10 minutes at 23°C).
  • Procedure D: Hot contact (30 minutes at 90°C or 120°C depending on food type).

  The standard also covers preparation and handling of samples, including large sample testing for unevenly sided materials to prevent migration artifacts.

• Evaluation and Reporting
  Colour fastness is graded from 1 (poor) to 5 (excellent) against the grey scale. The test report must clearly state sample identification, testing procedure, test fluids used, results, and any deviations from the standard.

Applications

SIST EN 646:2019 is critical for manufacturers and quality control laboratories involved in producing food packaging paper and board. Its application ensures:

• Food Safety Compliance
  Preventing colour bleeding helps maintain food purity and meets regulatory requirements for materials in food contact.

• Packaging Quality Assurance
  Verifies the durability of dyes used in food packaging under various conditions, including oil contact and hot food exposure.

• Design and Development
  Supports innovation by providing reliable methods to test novel dyed papers and boards before market release.

• Regulatory Alignment
  Harmonizes testing across Europe, aiding manufacturers to comply with national standards and EU food contact legislation such as Commission Regulation (EU) No 10/2011.

Related Standards

• EN 20105-A03: Grey scale for assessing staining, used for evaluating colour fastness results.
• EN ISO 186: Sampling techniques to ensure representative test specimens.
• EN ISO 3696: Specification for laboratory water used in testing.
• ISO 6588-2: Measurement of pH in aqueous extracts of paper and board.
• Commission Regulation (EU) No 10/2011: Food contact materials regulation including vegetable oils used as test fluids.

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By adhering to SIST EN 646:2019, organizations can confidently assess and certify the colour fastness of food contact papers and boards, ensuring safety, compliance, and high-quality packaging performance.

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2019
1DGRPHãþD
SIST EN 646:2006
Papir, karton in lepenka, namenjeni za stik z živili - Ugotavljanje obstojnosti barve
v obarvanem papirju, kartonu in lepenki
Paper and board intended to come into contact with foodstuffs - Determination of colour
fastness of dyed paper and board
Papier und Pappe vorgesehen für den Kontakt mit Lebensmitteln - Bestimmung der
Farbechtheit von gefärbtem Papier und Pappe
Papiers et cartons destinés à entrer en contact avec les denrées alimentaires -
Détermination de la solidité de la couleur des papiers et cartons colorés
Ta slovenski standard je istoveten z: EN 646:2018
ICS:
67.250 Materiali in predmeti v stiku z Materials and articles in
živili contact with foodstuffs
85.060 Papir, karton in lepenka Paper and board
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 646
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2018
EUROPÄISCHE NORM
ICS 67.250; 85.060 Supersedes EN 646:2006
English Version
Paper and board intended to come into contact with
foodstuffs - Determination of colour fastness of dyed paper
and board
Papiers et cartons destinés à entrer en contact avec les Papier und Pappe vorgesehen für den Kontakt mit
denrées alimentaires - Détermination de la solidité de Lebensmitteln - Bestimmung der Farbechtheit von
la couleur des papiers et cartons colorés gefärbtem Papier und Pappe
This European Standard was approved by CEN on 22 July 2018.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 646:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Principle . 4
5 Materials and equipment . 5
6 Reagents . 5
7 Sampling . 5
8 Preparation of sample . 6
9 Procedure. 6
10 Test conditions . 6
11 Evaluation . 7
12 Test report . 7
Annex A (informative) Determination of the fastness of fluorescent whitened paper and
board on large samples . 8
A.1 Scope . 8
A.2 Preparation of large samples . 8
A.3 Test report . 8
Bibliography . 9

European foreword
This document (EN 646:2018) has been prepared by Technical Committee CEN/TC 172 “Pulp, paper
and board”, 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 May 2019, and conflicting national standards shall be
withdrawn at the latest by May 2019.
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 646:2006.
With regard to EN 646:2006 the following changes have been made:
a) Clause 1 “Scope” has been revised and extended;
b) in Clause 6 “Reagents” the test fluid “saliva simulant ” has been removed and the test fluid “alkaline
salt solution” has been introduced;
c) new test conditions, matching the use of the tested papers and boards have been included;
d) new definition for the glass fibre papers has been included;
e) evaluation against a grey scale only has been included;
f) editorial changes.
Attention shall be drawn to the fact that the glassfibre papers have not been duly validated before the
publication of this standard.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
1 Scope
This document describes procedures for the testing of dyed paper and board intended to come into
contact with foodstuffs. Some procedures depending on the foreseeable use of the material are given.
Visual evaluation against a grey scale provides grading of the bleeding.
For samples having significant different sides, a migration can occur from one glass fibre to the other
and could lead to wrong interpretation of the fastness of one side. It is advisable to check these samples
using large sampling procedure to prevent cross contamination of the glass fibre during the migration
procedure. The procedure is described in Annex A. If lower limit of detection is required, this procedure
could also be used.
2 Normative references
...