Method and apparatus for forming films

The apparatus according to the invention is for forming filled pouches and it comprises: (a) a vacuum supply apparatus, (b) an elongated conveyor support, (c) an elongated row of vacuum apertures leading from the vacuum supply apparatus and discharging through the conveyor support, (d) a sequence of processing stations above the row of apertures in the conveyor support and which comprise holding, forming, filling and sealing stations, (e) a conveyor which includes a plurality of recessed vacuum moulds in its upper surface and mounted to slide over the conveyor support through each the processing station, (f) vacuum orifices extending through the conveyor into the vacuum moulds for transferring under-pressure from the vacuum apertures to each of the moulds, (g) means for supplying formable sheet material on to the conveyor at or ahead of the holding station, (h) drive means for driving the conveyor carrying the sheet material through the processing stations, and (i) means for supplying into the mould recesses through the vacuum apertures and the vacuum orifices a forming under-pressure at the forming station and at one or more subsequent processing stations wherein the under pressure at the forming station is greater than the under-pressure at one or more (and preferably all) of the subsequent processing stations and wherein the film is polymeric and is selected from the group consisting of polyvinyl alcohols, polyvinyl pyrrolidone, polyalkylene oxides, (modified) cellulose, (modified)cellulose-ethers or -esters or -amides, polycarboxylic acids and salts including polyacrylates, copolymers of maleic/acrylic acids, polyaminoacids or peptides, polyamides including polyacrylamide, polysaccharides, including starch and gelatine, natural gums, such as xanthum and carragum.