BS/EN 646-2018 pdf download.Paper and board intended to come into contact with foodstuffs – Determination of colour fastness of dyed paper and board.
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 colourfastness — Part A03: Grey scale for assessing staining (ISO 105-A 03)
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 (iSO 3696)
ISO 65882. Paper, board and puips- Determination of pH of aqueous extracts — Part 2: Hot extraction
3 Terms and definitions
For the purposes ot this document, the lollowing term and delinition applies.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.orgj
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
colour fastness
lack of transfer of colour from a paper to a non-stained glass-fibre paper, saturated with a test fluid and evaluated visually for staining against a grey scale
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 against a grey scale. The test fluids used are distilled or deionized water, diluted acetic acid, alkaline salt solution and olive oil depending on the type of contact expected.
5 Materials and equipment
5.1 Unstained glass fibre papers’) of 60 mm x 90 mm. The glass fibre papers shall meet the following conditions:
a) grammage 70 g/m²
9 Procedure
9.1 In case of test conditions D, the glass plates (52), the mass (5.4) and the vegetable oil (fA) are stored for 1 h at testing temperature in a drying cupboard (5.&); distilled or deionized water (i.1) is boiled in kettle (52). Thc use of cotton gloves is sufficient.
9.2 Immerse two sheets of unstained glass fibre papers (51) in a test fluid (6J.. 62.6.3 or 6A). Remove the sheets after saturation and free the sheets from excess fluid by wiping on the rim of the container.
9.3 Place one sheet of unstained glass fibre paper with its smooth side upwards on the glass plate (52). Place the test piece (C1au8) immediately on the unstained glass fibre paper. Cover it with the second saturated sheet of unstained glass fibre paper, so that the smooth side of the unstained glass fibre paper is in contact with the test piece again. Place a second glass plate (52) on top of the second unstained glass fibre paper and for procedures A and B wrap the total assembly in polyethylene film (5.3) to prevent the edges from drying out, load it with a mass of 1 kg (5A) and allow it to stand under the condition of Tahk2 with protection against direct light penetration.
9.4 If test pieces of a grammage of> 140 g/m2 are to be investigated, an appropriate even number of unstained glass fibre paper layers (5.1) is used so that the total of their grammages just exceeds the grammage of the test piece.
9.5 After the storage time open the assembly. Place the unstained glass fibre papers on 3 adjacent glass rods. 0 8 mm to 0 10 mm, with the side which was in contact with the test piece upwards, cover them without contact to prevent light penetration and air-dry at ambient temperature. Unstained glass fibre papers saturated with olive oil are not dried.
10 Test conditions
Table 2 describes the test conditions of EN 646.
11 Evaluation
Evaluate the staining of the glass fibre papers on the side with which they were in contact with the sample using the grey scale (55). When several layers of unstained glass fibre papers are used, evaluate only the layer that was in contact with the test piece. lithe two sides of the sample produce different results, the test report shall state to which side of the sample the data relates.
For the grading a distinction is drawn between different evaluation grades: Grade one signifies poor fastness; grade five signifies good fastness. The grade of the grey scale which is the most similar to the stained glass fibre paper, beginning at 4/5, is given as the evaluation grade of the tested paper. The choice between S and 4/S is also made to the most similar grade.
In the case that paper or board Is coming into contact with foodstuffs only with one side (e.g. food packaging) and it is known which side is facing the food, only this side will be evaluated.BS/EN 646-2018 pdf download.