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The present invention relates to rigid-buckling-resistant-fluted containers with an arcuate outer rim. The container such as a pressformed paperboard plate of overall diameter “D” including a generally planar bottom region, an upwardly extending fluted region surrounding the generally planar bottom

The present invention relates to rigid-buckling-resistant-fluted containers with an arcuate outer rim. The container such as a pressformed paperboard plate of overall diameter “D” including a generally planar bottom region, an upwardly extending fluted region surrounding the generally planar bottom region, and an outwardly and downwardly extending peripheral region having an arcuate radial profile. The containers being produced of a lightweight board but exhibiting high strength and rigidity relative to the low weight board.

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1. A press formed paperboard container of overall diameter “D” having: a) a generally planar bottom region;b) an upwardly extending fluted region surrounding said generally planar bottom region;c) an outwardly and downwardly extending peripheral region having an arcuate radial profile and pleats wit

1. A press formed paperboard container of overall diameter “D” having: a) a generally planar bottom region;b) an upwardly extending fluted region surrounding said generally planar bottom region;c) an outwardly and downwardly extending peripheral region having an arcuate radial profile and pleats with substantial resistance to opening formed therein, the downward extent of said outwardly and downwardly extending peripheral region being at least 0.01D, and the radial extent of said outwardly and downwardly extending peripheral region being at least 0.017D, wherein each flute in the upwardly extending fluted region has an uppermost extremity, and wherein said pleats terminate at or about said uppermost extremity. 2. The press formed paperboard container of claim 1, wherein the container is a plate or bowl. 3. The press formed paperboard container of claim 2, wherein the board is coated with polypropylene in an amount ranging from about 5 to about 20 lbs per 3000 sq. ft. ream. 4. The press formed paperboard container of claim 2, wherein the container is a plate and wherein the plate is coated with styrene butadiene/calcium carbonate. 5. The press formed paperboard container of claim 2, wherein the outwardly and downwardly extending peripheral region adjoins said upwardly extending fluted region. 6. The press formed paperboard container of claim 2, wherein the upwardly extending fluted region is separated from said outwardly and downwardly extending peripheral region by an annular region of paperboard. 7. The press formed paperboard container of claim 2, wherein the container is a plate and wherein the paperboard from which said plate is formed bears a clay coating on its upper surface. 8. The press formed paperboard container of claim 7, wherein the clay coating on the upper surface of the paperboard from which said plate is formed has a coating weight of between 8 and 15 pounds per 3000 square foot ream. 9. The press formed paperboard container of claim 2, wherein the container is a plate and wherein the pleats in said outwardly and downwardly extending peripheral region having an arcuate radial profile are generally linear and are evenly spaced about the periphery of said plate. 10. The press formed paperboard container of claim 2, wherein the pleats in said outwardly and downwardly extending peripheral region having an arcuate radial profile have a cross-section generally in the form of an inverted “Ω” (omega). 11. The press formed paperboard container of claim 2, wherein the pleats in said outwardly and downwardly extending peripheral region having an arcuate radial profile are formed from radially extending scores. 12. The press formed paperboard container of claim 2, wherein the container is a plate and wherein paperboard from which said plate is formed has a basis weight of between 80 and 155 pounds per 3000 square foot ream. 13. A stack of plates according to claim 1, wherein two or more plates are nested with substantial absence of adherent bonds between surfaces of adjacent plates. 14. A stack of plates according to claim 1, wherein two or more plates are nested into a stack, and wherein adjacent plates in said stack are formed simultaneously during a single pressing stroke in a single die set. 15. The press formed paperboard container of claim 2, wherein each flute in the upwardly extending fluted region is separated from the adjacent flutes by a generally frustoconical land region having a width of at least 0.005D at its uppermost extremity. 16. The press formed paperboard container of claim 2, wherein each flute in the upwardly extending fluted region flares upwardly and outwardly from the generally planar bottom region defining a scallop-shaped concavity having a width of at least about 0.03D at its uppermost extremity. 17. The press formed paperboard container of claim 2, wherein said generally planar bottom region has a crown having a height of no more than 0.05D. 18. The press formed paperboard container of claim 2, wherein said generally planar bottom region has a gravy ring having a depth of no more than 0.05D formed thereabout. 19. The press formed paperboard container of claim 1, wherein a junction between the downwardly extending peripheral region and said upwardly and outwardly extending interior wall define a scalloped edge. 20. The press formed paperboard container of claim 1, wherein a junction between the outwardly and downwardly extending peripheral region and said upwardly extending fluted region defines a scalloped edge having a radius of curvature of between 0.025″ and 0.125″. 21. The press formed paperboard container of claim 1, wherein the downward extent of said outwardly and downwardly extending peripheral region is from 0.01D to about 0.04D. 22. The press formed paperboard container of claim 1, wherein the radial extent of said outwardly and downwardly extending peripheral region is from 0.017D to about 0.088D. 23. A press formed paperboard container of overall diameter “D” having: a) a generally planar bottom region;b) an upwardly extending fluted interior wall region surrounding said generally planar bottom region;c) an outwardly and downwardly extending peripheral region having an arcuate radial profile formed therein, the downward extent of said outwardly and downwardly extending peripheral region being at least 0.01D inch, and the radial extent of said outwardly and downwardly extending peripheral region being at least 0.017D, wherein a junction between the outwardly and downwardly extending peripheral region and said upwardly extending interior wall defining a scalloped edge, said scalloped edge having a radius of curvature of between 0.025″ and 0.125″. 24. The press formed paperboard container of claim 23, wherein the container is a plate or a bowl. 25. The press formed paperboard plate container of claim 24, wherein the hoop strength of said outwardly and downwardly extending peripheral region being substantially greater than that of said upwardly and outwardly extending interior wall region. 26. The press formed paperboard plate container of claim 24, wherein pleats in said outwardly and downwardly extending peripheral region exhibiting substantial resistance to opening. 27. The press formed paperboard plate container of claim 24, wherein pleats in said outwardly and downwardly extending peripheral region have a cross-section generally in the form of an inverted “Ω” (omega). 28. The press formed paperboard plate container of claim 24, wherein the container is a plate and wherein the weight of the paperboard from which said plate is formed being less than 155 lbs/3000 sq ft ream. 29. The press formed paperboard plate container of claim 24, wherein the container is a plate and wherein a load deflection curve of said plate increases monotonically up to a load of at least 200 grams. 30. The press formed paperboard plate container of claim 26, wherein a plurality of said pleats being capable of sustaining a load of at least about 2 lbs/0.625″ strip without extending in excess of 0.02″. 31. The press formed container of claim 23, wherein the container is a plate, and wherein the plate is formed from a circular blank having between 30 and 75 score lines formed therein. 32. The press formed container of claim 23 wherein the container is a plate, and wherein said upwardly extending fluted region has between 30 and 80 flutes formed therein. 33. The press formed container of claim 23, wherein the container is a plate, wherein the plate is formed from a circular blank having between 30 and 75 score lines formed therein, and wherein the number of score lines does not equal the number of flutes. 34. The press formed paperboard plate of claim 33, wherein the number of flutes is at least 5 more than the number of score lines. 35. The press formed paperboard container of claim 23, wherein the downward extent of said outwardly and downwardly extending peripheral region is from 0.01D to about 0.04D. 36. The press formed paperboard container of claim 23, wherein the radial extent of said outwardly and downwardly extending peripheral region is from 0.017D to about 0.088D. 37. A press formed paperboard container of overall diameter “D” having: a) a generally planar bottom region;b) an upwardly and outwardly extending fluted interior wall region surrounding said generally planar bottom region; andc) a downwardly extending peripheral region, the downward extent of said downwardly extending peripheral region being at least 0.01D, the junction between the downwardly extending peripheral region and said upwardly and outwardly extending interior wall defining a scalloped edge having a radius of curvature of no more than 0.125″. 38. The press formed paperboard container of claim 37, wherein an outwardly extending annular evert is formed about said outwardly and downwardly extending arcuate peripheral region extending outwardly at an eversion angle β of at least about 25 degrees with respect to the lowermost downwardly sloping portion of the outwardly and downwardly extending arcuate peripheral region. 39. The press formed paperboard container of claim 37, wherein the upwardly and outwardly extending flexible interior wall region spans a radial extent (delta X) of between about 0.15″ and 0.25″ while having a height (delta Y) of between about 0.2″ and 0.5″. 40. The press formed paperboard container of claim 37, wherein each flute in the upwardly extending fluted region flares upwardly and outwardly defining a scallop-shaped concavity increasing in width and depth from its lower terminus near the generally planar bottom region to its uppermost extremity. 41. The press formed paperboard container of claim 40, wherein said pleats terminating at or about said scalloped edge. 42. The press formed paperboard container of claim 40, wherein the degree of pressing of any pleats interior to said scalloped edge is controlled such that the hoop strength of said upwardly extending region is substantially less than that of said outwardly and downwardly extending peripheral region. 43. The press formed paperboard container of claim 37, wherein the downward extent of said outwardly and downwardly extending peripheral region is from 0.01D to about 0.04D. 44. The press formed paperboard container of claim 37, wherein the junction between the downwardly extending peripheral region and said upwardly and outwardly extending interior wall define a scalloped edge having a radius of curvature of between 0.025″ and 0.125″.