Abstract: A lamp glass for a motor vehicle, such as a headlamp or indicating lamp glass, is of a plastics material such as polycarbonate, and is subjected to treatment with ultraviolet radiation before a protective coating is deposited on it.

Abstract: The invention relates to a belt and pulley transmission which is preferably but not essentially an infinitely variable transmission. The belt is formed from a stack of individual blocks working in compression and supported on one or more support bands. According to the invention, the blocks are formed from sintered metal material, while the bands which support and compress the blocks are made from aramide fibres, such as KEVLAR. Every tenth block is of sintered bronze, to reduce the risk of seizing, the remaining blocks being of sintered iron.

Abstract: A friction lining suitable for brakes, clutches etc. comprises mineral fibres which contain alumina, Al.sub.2 O.sub.3, silica, SiO.sub.2, and lime, CaO. The mineral fibres have a percentage by weight of alumina, Al.sub.2 O.sub.3, of between 18% and 25%, a percentage by weight of silica, SiO.sub.2, of between 38% and 45% and a percentage by weight of lime, CaO, of between 23% and 33% and preferably of the order of 27%. Moreover, the mineral fibres contain iron oxide, Fe.sub.2 O.sub.3, in a proportion by weight of between 0.5% and 1%, alkali metal oxides, Na.sub.2 O and K.sub.2 O, in a proportion by weight of between 4% and 10% and magnesia, MgO, in a proportion by weight of between 0.5% and 3%.