BS EN ISO 787-25:2006 2007
$102.76
General methods of test for pigments and extenders – Comparison of the colour, in full-shade systems, of white, black and coloured pigments. Colorimetric method
| Published By | Publication Date | Number of Pages |
| BSI | 2007 | 16 |
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 1 | BRITISH STANDARD BS EN ISO 787-25:2006 BS 3483-A7:2006 Methods for Testing pigments for paints – Part A7: Colorimetric method for the comparison of the colours, in full-shade systems, of white, black and coloured pigments |
| 2 | This British Standard, having been prepared under the direction of the Surface Treatments and Coatings Standards Policy Committee, was published under the authority of the Standards Board and comes into effect on 15 March 1994 Committees responsible for this British Standard |
| 3 | Contents |
| 4 | National foreword |
| 9 | 1 Scope 2 Normative references 3 Definitions 3.1 full-shade system 3.2 full-shade colour 3.3 mass tone 4 Principle |
| 10 | 5 Materials 5.1 Alkyd resin (binder) 5.2 Fumed silica 5.3 Preparation of the test medium Table 1 – Recommended quantities of white pigment and test medium Table 2 – Recommended quantities of coloured and black pigments and test medium 6 Apparatus 6.1 Photometer 6.1.1 For coloured and white pigments 6.1.2 For black pigments a) Accuracy b) Calibration and zero adjustment |
| 11 | Figure 1 – Black standard c) Standard deviation of tristimulus values 6.2 Substrate, of minimum dimensions 150 mm × 50 mm, uniform, non-fluorescent, compatible with the binder to be used and appropriate to the method of colour comparison. 6.3 Film applicator, for the application of the pastes of the test pigment and the agreed reference pigment to the substrate. 6.4 Stencil card (for covering specimens that are still moist when presented for measurement), approximately 0,5 mm thick, with … 6.5 Automatic muller, with ground-glass plates, preferably water-cooled. The plates shall be of diameter 180 mm to 250 mm and su… 6.6 Spatula, with flexible steel or plastic blade. 7 Sampling 8 Procedure 8.1 Test portion 8.1.1 White pigments 8.1.2 Coloured and black pigments |
| 12 | 8.2 Preparation of pigment dispersions 8.3 Preparation of test specimens 8.3.1 General 8.3.2 White pigments 8.3.3 Coloured and black pigments 8.3.3.1 Hiding layers for evaluating differences in full-shade colour 8.3.3.2 Non-hiding layers for evaluating differences in mass tone 8.4 Measurement |
| 13 | 9 Expression of results 9.1 White pigments and black pigments 9.1.1 Relative hue Table 3 – Name of relative hue 9.1.2 Amount of chromaticity difference 9.2 Lightness difference 9.3 Coloured pigments 10 Test report a) all details necessary to identify the product tested and the agreed reference pigment; b) a reference of this part of ISO 787 (ISO 787-25); c) the composition of the mill base (see 8.1); d) the method of preparation of the test specimens; e) the number of revolutions chosen if a muller was used; f) If available, the film thickness, the pigment concentration and the substrate; g) whether full-shade or mass tone; h) the type of apparatus (spectrometer or tristimulus colorimeter) and the measurement geometry used; i) the results of the test as indicated in clause 9; j) any deviation from the test method specified; k) the date of the test. |
| 15 | List of references |
| 16 | BS EN ISO 787-25:2006 BS 3483-A7:2006 |
