964,369. Rollers. IMPERIAL CHEMICAL INDUSTRIES Ltd. Jan. 25, 1963 [Feb. 19, 1962], No. 6292/62. Heading F2U. [Also in Division H5] A hollow roller 1 is heated to an accurately controlled temperature by means of a stationary aluminium cylinder 3 in which a resistance heater 4 is embedded and which has a cavity 5 containing a sintered bronze slipper 7 urged by springs 10 into contact with the inner walls of the roller and containing the bulb 8 of a thermistor and a thermocouple 9. The cavity 5 is lagged by a thermal insulator 6 so that the slipper assumes the temperature of the roller and the thermistor controls this temperature. The sintered bronze of the slipper may be impregnated with a lubricant such as polytetrafluoroethylene to avoid frictional heating of the slipper, alternatively the slipper may be made from copper, silver or aluminium. Methods of heating other than electrical may be employed and other temperature control arrangements may be used. As shown the roller driving shaft 2 passes freely through the heating cylinder 3.