BS EN 646:2018 pdf free.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 othe 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
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.
EN 20105-A03, Textiles-Tests for colour fastness-Part A03: Grey scale for assessing staining(ISO 105-A03) EN ISO 186, Paper and board-Sampling to determine average quality(ISO 186)
EN ISO 3696, Water for analytical laboratory use-Specification and test methods(IS0 3696)
ISO 6588-2,Paper, board and pulps-Determination of pH of aqueous extracts-Part 2: Hot extraction
4 Principle
A sample is brought into contact with glass fibre papers which have been saturated with a test fluid and placed under load for a given time and temperature. The staining of the glass fibre paper is evaluated salt solution and olive oil depending on the type of contact expec Lvater, diluted acetic acid, alkaline against a grey scale.The test fluids used are distilled or deionized.
7 Sampling
If a lot is tested then sampling is carried out in accordance with EN ISO 186.
8 Preparation of sample
Cut or punch several test pieces of 50 mm x 20 mm from the sample under investigation. Smooth edges shall be obtained.
9 Procedure
9.1 In case of test conditions D, the glass plates(5.2),the mass (5. 4)and the vegetable oil (6.4) are stored for 1 h at testing temperature in a drying cupboard (5.6);distilled or deionized water (6.1) is boiled in kettle (5.7). The use of cotton gloves is sufficient.