The retention behaviour of twenty four anionic, cationic, sulphonated and amphoteric synthetic dyes has, been examined on plain and coconut oil impregnated egg shell layers using pure metha nol, pure acetonitrile and methanol-water, acetonitrile-water, acetonitrile-methanol and acetonitrile-acetone mixed mobile phases. The mobile phase composition and the effect of solubility of dyes on hR(f) values have been discussed. The mechanism of migration is explained in terms of partition on impregnated egg shell layers and the polarity of the mobile phase used. The acetonitrile-acetone (75:25) system was found to be most effective and gave several quaternary separations of dyes. A large number of separations of same coloured dyes as well as having approximately similar structural formula have been achieved. The separation of acidic dyes from basic dyes; acidic dyes from acidic dyes; and acidic dyes from amphoteric dyes are of special interest.