Container having a high degree of thermal insulation

Claim 1

A container having a high degree of thermal insulation, comprising a preformed inner vessel having a frustroconical collar with an angle of convergence in the range 3° to 15°, a preformed, two-part outer vessel having a frustroconical collar with an angle of convergence in the range 3° to 15°, and a smooth-walled pre-cut neck tube connecting said inner and outer vessels together, end portions of said tube being received in said frustroconical collars of the respective vessels with an interstitial space defining a minimum radial gap up to 0.5 mm between each neck tube end portion and the respective frustroconical collar, and adhesive material received in the interstitial spaces for bonding the neck tube end portions in said frustroconical collars and defining respective bonded joints, the collars of the inner and outer vessels being frustroconical for substantially the extent of said bonded joints and the lengths of the collars, and each frustoconical collar at the beginning of its angle of convergence extending directly from a wall of the vessel to which it is associated, each wall defining a major enclosing surface of each respective vessel, said adhesive material in said interstitial spaces forming a continuous bond up to 0.5 mm thickness over a significant length of the neck tube end portion, wherein the axial length of the collars measured from the minimum radial gap between the tube neck ends and their respective frustoconical collars is between 10 and 30 min.