Treatment of fibrous materials

The specification describes and claims a method of treating fibrous material which comprises applying to the fibrous material a composition comprising an organosilicon compound having a group =NCO(CHR)nOH connected with a silicon atom of the organosilicon compound. The organosilicon compound consists of or comprises (A) a silane according to the general formula R¹aAbSi(R˝NXR′)c or (B) a polysiloxane comprising one or more siloxane units according to the general formula any remaining units of the polysiloxane being at least predominantly according to the general formula A represents a hydroxyl or a hydrolysable group, R¹ represents a monovalent hydrocarbon group having up to 8 carbon atoms, R² represents a hydroxyl group, a group R¹, a group OR¹ or a group COR¹, R⁴ represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group or an aryl group, R′ represents a group R⁴ or a group X, R˝ represents a divalent hydrocarbon group which may have nitrogen, oxygen or sulphur present in the carbon chain, X represents a group CO(CHR)nOH in which R represents a hydrogen atom, a hydroxyl group, a hydrocarbon group or a hydroxyl substituted hydro- carbon group a has the value 0, 1 or 2, b has the value 1, 2 or 3, c has the value 1 or 2, the sum of a + b + c = 4, m has the value 0, 1 or 2, p has the value 1 or 2, q has the value 0, 1, 2 or 3, r has the value 0, 1 or 2 and n has a value in the range 2 to 7. Fabrics treated according to the method have a satisfactory handle and improved non-yellowing properties.