Abstract: An elongated sheet (10) is used to form a thermally insulated cup (30). The sheet includes a pair of spaced apart smooth portions (12, 13) connected by a middle portion (11). The smooth portions are folded on opposite sides of the middle portion. The middle portion is corrugated or otherwise distorted or deformed to create air space. The folded sheet is wound around a mandrel to form a cylinder. The ends of the smooth portions are joined together, and a bottom closure (14) is attached to form the cup. The finished cup includes a smooth outer shell (12S), a smooth inner shell (13S), and a middle layer (11L) sandwiched therebetween. The middle layer forms many air spaces between the shells to thermally insulate the contents of the cup, and also provide structural strength. The cup can be constructed of paper, which makes it biodegradable and recyclable, and its simple construction method makes it easy and inexpensive to manufacture using standard, conventional machinery. In an alternative embodiment (FIG.

Abstract: An elongated sheet (10) is used to form a thermally insulated cup (30). The sheet includes a pair of spaced apart smooth portions (12, 13) connected by a middle portion (11). The smooth portions are folded on opposite sides of the middle portion. The middle portion is corrugated or otherwise distorted to create air space. The folded sheet is wound around a mandrel to form a cylinder. The ends of the smooth portions are joined together, and a bottom closure (14) is attached to form the cup. The finishell cup includes a smooth outer shell (12S), a smooth inner shell (13S), and a middle layer (11L) sandwiched therebetween. The middle layer forms many air spaces between the shells to thermally insulate the contents of the cup, and also provide structural strength. The cup can be constructed of paper, which makes it biodegradable and recyclable, and its simple construction method makes it easy and inexpensive to manufacture using standard, conventional machinery. In an alternative embodiment (FIG.

Abstract: A thermally insulated cup or container (30) includes a smooth outer shell (12S), a smooth inner shell (13S), a corrugated layer (11L) sandwiched therebetween, and a bottom closure (14). The inner shell, corrugated layer, and outer shell are formed by simply winding a continuous elongated paper sheet (10) in a three-layered spiral, then sealing them together. The corrugated layer forms many air pockets between the shells to thermally insulate the contents of the cup, and also provide structural strength. The paper construction of the cup makes it biodegradable and recyclable, and the simple construction method of the cup makes it easy and inexpensive to manufacture.