Packaging

896,753. Packaging. NATIONAL DAIRY PRODUCTS CORPORATION. June 28, 1960, No. 22575/60. Class 94(1). A package with a removable cover sheet 12, Fig. 3, is formed from a container 8 of rectangular or square form having a border flange 10, the border flange 10 being provided with a line of weakness 14 along one side of the cup and underlying the cover sheet 12 whereby an edge portion 22 of the container flange beyond the line of weakness 14 may be pulled away to peel the cover sheet 12 from the border flange 10. The line of weakness 14 may be formed by a score-line, a series of perforations, or a strip of material disposed along the border flange 10 as a substitute for the flange material beyond the line of weakness. The packages may be made by forming a spaced series of cups 8, Fig. 1, in a strip 18 of thermoplastic material, filling the cups successively with the material being packaged, forming a line of weakness 14 in one border flange 10 by co-operating knife edged rollers 26 and 28 or other cutting means, placing a continuous cover strip 20 in position, forming a hermetic seal, without fusion or welding, by compressing and heating the cover 20 to the flange 10 by means of a bed 32 and platen 34, and then separating the sealed cups from each other by a suitable cutting mechanism (not shown). Alternatively the cover strip 20 may be secured in position by an adhesive. The cups 8 are formed by feeding the thermoplastic material step by step through the apparatus, heating the material to make it stretchable, and then forming the heated area into the desired shape by gas pressure, or a vacuum, or with suitable dies. Specification 778,496 is referred to.