An aqueous solution includes a polyalkylene glycol terminated poly-carbodiimide of formula 1:

##STR00001##

where: R.sub.1 is an aliphatic group from about 5 to about 12 carbon atoms, an isosorbide moiety, a 1,3-furan moiety, an L-lysine alkyl ester moiety, a rosin moiety, a cycloaliphatic unsaturated moiety, or a cardanol moiety; R.sub.2 is hydrogen or a methyl group; R.sub.3 is a methyl, ethyl, or propyl moeity; and n and m are integers and are each independently between 1 and about 30. The solution is optically clear.

According to the present invention, there is provided a fabric substrate for mounting a light emitting element. The fabric substrate comprises a fabric layer including at least one fabric, a stress buffer layer that is disposed on the fabric layer and minimizes an occurrence of physical strain and stress caused by bending the fabric layer, and a flattening layer that is disposed on the stress buffer layer and provides a flat surface to allow a light emitting element to operate.