Abstract: This invention relates to plastic sheet material, and in particular concerns the production of a plastics sheet material which has a wide range of uses, because of the properties thereof.

Abstract: A method of forming plastic sheet material into articles. The sheet is heated and is formed into the article in a mould. The mould parts severe the portion of the sheet which is to be formed into the article and at the peripheral edge of the said portion the mould parts squeeze the plastics material to cause it to flow outwardly into a bead cavity in which the material forms into a thickened bead.

Abstract: This invention pertains to a method for thermoforming thin-walled plastics articles from an elongated polyolefin web which is manufactured so as to have minimum orientation so that it will expand lengthwise and widthwise when passed through a heating zone prior to thermoforming, which method comprises moving the web both laterally and longitudinally in a co-ordinated manner whereby the normal inclination of the web to sag because of the longitudinal and lateral expansion of the web due to heating is effectively eliminated.

Abstract: A method for molding thermoformable synthetic plastic sheet material into a circular lid having a downturned rim with a bead on its inner face. The sheet material is softened by heating and disposed between male and female dies which are moved together to fold the sheet material over the male die to form the downturned rim. The material forming the rim is compressed and sheared between the dies to force material into a bead cavity in the male die to form the bead. The molded lid can fit over the top edge of a container with the bead in sealing engagement with the container.