Abstract
The effect of surfactants derived from amino acid on the detergency for carbon black soil, palmitic acid and mixed fatty acid as a model of oily soil from a cotton fabric were studied. In addition, the soiling of a polyester fabric by carbon black soil and emulsification of olive oil in N-acyle amino acid surfactant of aqueous solution were also estimated.
Since we have ascertained the excellent performance of N-acyle amino acid surfactant through an extensive investigation, we wish to report the results.
1) The detergency of carbon black component was effective for cotton fabric in the order of: soap>HS21 (N-acyle amino acid surfactant) >SDS at 20°C, 40°C and 60°C. The detergency of HS-21 was less decreased in the hard water than that of a soap, though the detergency of SDS increased with increa-sing water hardness.
2) The soiling of a polyester fabric by carbon black soil in HS-21 aqueous solution was very low, even if water hardness increased.
3) Since the emulsification with HS-21 was much superior to that of SDS, HS-21 were more effective in removal of palmitic acid and mixed fatty acid than SDS.
4) The fatty acid was removed from cotton fabrics in the order of C8>C10>C12<C18. A fatty acid of lower melting point except oleic acid was removed easier than those of higher melting point.
5) The removability of saturated and unsaturated fatty acid is dependent on the kind of fiber. Unsaturated fatty acid (oleic acid) was removed from a fabric in the order of: polyester>cotton. On the other hand the order of that of saturated fatty acid (palmitic acid) was cotton>polyester.
