Abstract: A container having an annular sidewall with upper and lower annular peripheral edges and a lattice structure of elongate ribs interconnecting the upper and lower annular peripheral edges, wherein the lattice structure is an open framework defining a plurality of sidewall openings, and a base having an annular peripheral edge which is integral with the lower annular peripheral edge of the sidewall, the annular peripheral edge of the base surrounding a base wall structure which is integral therewith, the base wall structure having at least one injection moulding sprue at a central region of the base wall structure, wherein the at least one injection moulding sprue is connected to the upper annular peripheral edge of the annular sidewall by the base wall structure, the annular peripheral edge of the base, the lower annular peripheral edge of the sidewall and the lattice structure of the sidewall, wherein the sidewall and the base are composed of a thermoplastic polymer and define a central concavity for packagin

Abstract: A tray having: an annular sidewall having upper and lower annular peripheral edges, an upper annular peripheral rim which is integral with the upper annular peripheral edge, and a base having an annular peripheral edge which is integral with the lower annular peripheral edge of the sidewall, wherein the rim, the sidewall and the base are composed of a thermoplastic polymer and the sidewall and the base define a central concavity for packaging a product, wherein the base has a lattice structure of elongate foam ribs interconnected by foam junctions, wherein each foam rib has opposite ends, and each end is integrally connected to either the annular peripheral edge of the base or one of the foam junctions, wherein each foam rib and each foam junction has opposed upper and lower unfoamed solid skins of the thermoplastic polymer on opposite sides of a central cellular foam core of the thermoplastic polymer.

Abstract: A method of forming an article by controlling the thickness of a portion of the plastic composition which comprises a layer of molten plastic composition between opposite first and second solid skins, so that the thickness is constant with a very low tolerance of +/?0.5%, preferably +/?0.2%, when the portion is subsequently exposed to a reduced pressure to cause expansion of the layer of molten plastic composition to form a core layer of expanded cellular foam between the first and second solid skins, and by controlling the stretch of the first solid skin to be within the range of 0.5 to 3%, the expansion of the plastic composition can be highly uniformly controlled in the expanded wall parts.

Abstract: Methods of forming an article from a molten plastic composition comprising a polymer and a blowing agent. The methods include injecting the molten plastic composition into a mould, allowing the plastic composition to form a first solid skin adjacent to an in contact with a first cavity-forming surface of the mould and a second solid skin adjacent to and in contact with a second cavity-forming surface of the mould, and then opening the mould before the molten plastic composition between the first and second solid skins in at least one portion of the circumference of a region of the mould cavity defining an annular cross-section of the cavity has solidified.

Abstract: A hollow article for use as a beverage cup, or as a container, the hollow article having an annular sidewall and a base wall defining a central hollow cavity, a top rim of the sidewall and a bottom end of the sidewall, wherein the annular sidewall has a plastics material composed of a sandwich structure of inner and outer skins and an integral expanded cellular foam layer therebetween, wherein at least a portion of the annular sidewall has an inner surface of the sandwich structure inclined at a first acute angle to a longitudinal axis of the hollow article and an opposite outer surface of the sandwich structure inclined at a second acute angle to the longitudinal axis of the hollow article, wherein the second acute angle is greater than the first acute angle.

Abstract: Method of forming an article from a molten plastic composition including a polymer and a blowing agent.

Abstract: Methods of forming an article from a molten plastic composition comprising a polymer and a blowing agent. The methods include injecting the molten plastic composition into a mould, allowing the plastic composition to form a first solid skin adjacent to an in contact with a first cavity-forming surface of the mould and a second solid skin adjacent to and in contact with a second cavity-forming surface of the mould, and then opening the mould before the molten plastic composition between the first and second solid skins in at least one portion of the circumference of a region of the mould cavity defining an annular cross-section of the cavity has solidified.