Nestable, stackable containers

Claim 1

A nestable, stackable container comprising a continuous container body capable of being rapidly filled with and retaining a viscous liquid therein and having top and bottom walls joined by continuous side walls extending around the periphery of the container body, said container body having a forward portion terminating in a forwardly extending mouth part to provide access to the interior of the container, and a rearward portion thereof, and comprising (a) male or female die parts located on said top wall and adapted to cooperate with mating die parts on the botom wall of another container; (b) male or female die parts located on said bottom wall adapted to cooperate with mating die parts on the top wall of another container; (c) said forward portion of said container having a substantially convex curvilinear surface sloping continuously from said side walls to said mouth portion without intermediate shapes that upon rapid filling with said viscous liquid, will trap air within said container body; (d) said rearward portion of said container being formed with a substantially concave curvilinear surface sloping continuously from said side walls and conforming generally to the slope of the convex surface of said forwrad portion, so that a plurality of containers are stackable by mating male and female die parts on said top and bottom walls of said container, and nestable by juxtaposition of said convex and concave surfaces of a plurality of said containers, said surfaces being capable of contiguous relationship over major portions thereof whereby said convex and concave surfaces are in abutting and touching relationship so that a stack of containers will be better able to support itself.