ANNEX IIEXAMPLES OF THE CALCULATION OF PERCENTAGES OF THE COMPONENTS OF CERTAIN TERNARY MIXTURES USING SOME OF THE VARIANTS DESCRIBED IN POINT I.8.1 OF ANNEX I
VARIANT No 1
Using this variant, that is using two different specimens and removing one component (a = wool) by dissolution from the first specimen and a second component (b = polyamide) from the second specimen the following results can be obtained:
Treatment with alkaline sodium hypochlorite does not entail any loss in mass of polyamide, while unbleached cotton loses 3 %, therefore d1 = 1·0 and d2 = 1·03.
Treatment with formic acid does not entail any loss in mass of wool or unbleached cotton, therefore d3 and d4 = 1·0.
If the values obtained by chemical analysis and the correction factors are substituted in the formula under point I.8.1.1 of Annex I, the following result is obtained:
P3% (cotton) = 100 — (10·30 + 50·00) = 39·70
The percentages of the various clean dry fibres in the mixture are as follows:
| Wool | 10·30 % |
| Polyamide | 50·00 % |
| Cotton | 39·70 % |
These percentages must be corrected according to the formulae under point I.8.2 of Annex I in order to take account also of the conventional recovery rates and of the correction factors for any losses in mass after pre-treatment.
As indicated in Annex II to the Directive relating to textile names, the conventional recovery rates are as follows: carded wool 17·0 %, polyamide 6·25 %, cotton 8·5 %, also, unbleached cotton shows a loss in mass of 4 % after pre-treatment with light petroleum and water, Thus:
P3A% (cotton) = 100 — (10·97 + 48·37) = 40·66.
The composition of the yarn is therefore as follows:
| Polyamide | 48·4 % |
| Cotton | 40·6 % |
| Wool | 11·0 % |
| 100·0 % |