Improvements in the development of light-sensitive silver halide materials

摘要

Urethans are prepared as follows: (i) methoxypolyethylene glycol (M.Wt. 750) is reacted with bromoacetyl chloride to give methoxypolyethylene glycol bromoacetate which is in turn reacted with potassium isocyanate to give methoxypolyethylene glycol isocyanatoacetate and then ethanol, n-hexadecylol, ethylene glycol or a polyethylene glycol (M.Wt. 300 or 1000) to give the corresponding urethans or diurethans or (ii) methoxypolyethylene glycol (M.Wt. 750) is reacted with 2:5-diisocyanatotoluene or 1:6-diisocyanato-hexane to give a corresponding diurethan.