Table 2 UPF values, protection class and K/S values of plain weave fabric dyed with natural colorants at different concentrations
From: An evaluation of UV protection imparted by cotton fabrics dyed with natural colorants
| Â | Colorant | UPF | UV Protection Class | K/S |
|---|---|---|---|---|
Plain weave | 2% Madder | 11.1 | No Class | 0.20 |
| Â | 4% Madder | 15.8 | Good | 0.28 |
| Â | 6% Madder | 16.6 | Good | 0.38 |
| Â | 2% Cochineal | 28.5 | Very Good | 0.63 |
| Â | 4% Cochineal | 34 | Very Good | 0.79 |
| Â | 6% Cochineal | 36.6 | Very Good | 0.99 |
| Â | 2% Indigo | 43.1 | Excellent | 1.78 |
| Â | 4% Indigo | > 50 | Excellent | 2.56 |
| Â | 6% Indigo | > 50 | Excellent | 3.02 |