It is worth considering what you want to achieve and why.
PERMASET Inks have good – excellent light fastness. Most colours* achieve a rating of 8/8 on the Blue Wool Scale, but all are not less than 6/8. This is even better than many fine art acrylics. When fully cured, prints have excellent wash and dry clean fastness.
*All Glow colours and Phosphorescent Green exhibit diminished light fastness, particularly in direct sunlight.
The above considers pigments. The resins are another matter. The chemistry that allows the prints to cure and in doing so, to attain wash, rub and dry clean resistance is reactive and may compromise very long term viability of prints, particularly on fibres like cotton and particularly in settings where the prints are constantly exposed to strong light. In such an environment, the fibres would be likely to degrade in any case.
For applications such as these, PERMAPRINT Premium (PPP) would be a preferable choice. PPP confers the same pigment benefits but in an archival quality resin system. The UV resistance of the PPP resin system is such that it has excellent outdoor durability.
However, use of PPP would mean that the soft handle and launderability properties that are typically required for textile applications would be lost.
As above, it is worth considering what you want to achieve and why.