The partition of disperse dyes between water and cellulose acetate has been studied by means of desorption experiments, and the results have been used to calculate values for affinity, heat of dyeing, and entropy change. Aqueous solubilities have been determined at different temperatures in order to obtain heats of aqueous solution, and values for fibre saturation and heat of solution in the fibre have been calculated.

It is shown that the dispersing agents added to disperse dyebaths stabilise the dye suspension and act as restraining and retarding agents. With some dyes, especially at low temperatures, the normal retarding effect is reversed, probably owing to an increase in the rate of dissolution of crystalline particles of dye in presence of dispersing agent.

The rates of fading in daylight of British dyed‐wool light‐fastness standards have been measured in an industrial and in a rural area.