Abstract: Paper food trays that are able to be compactly stacked together and that contain side walls and a bottom with gusset corners formed by overlapping gusset panels and paperboard blanks for forming the trays are described herein. These nestable food trays are stronger than nestable food trays that do not contain a gusset corner. Further, they are particularly useful to carry and hold foods that include a sauce or other liquid. The food trays are generally temporarily leak proof, such as for at least about 5 minutes, preferably for at least about 10 minutes, more preferably for at least about 15 minutes, after the food is placed in the tray.

Abstract: An inwardly offset surface of the cover of a carton is cut in a plane transverse to the top of the cover. A protrusion on the bottom surface of a complementary recess in the latch flap extends through the hole to latch the carton with the protrusion being within the cover recess to prevent accidental opening of the carton. The mold for producing the carton cuts the hole while thermoforming by relative movement between a male key mounted in the male mold member and female key mounted in the female mold member. Both keys have flat surfaces transverse to the closing motion of the molds. These flat surfaces are biased into engagement one with the other so that the plastic is cut in a shearing action.

Abstract: An inwardly offset surface of the cover of a carton is cut in a plane transverse to the top of the cover. A protrusion on the bottom surface of a complementary recess in the latch flap extends through the hole to latch the carton with the protrusion being within the cover recess to prevent accidental opening of the carton. The mold for producing the carton cuts the hole while thermoforming by relative movement between a male key mounted in the male mold member and female key mounted in the female mold member. Both keys have flat surfaces transverse to the closing motion of the molds. These flat surfaces are biased into engagement one with the other so that the plastic is cut in a shearing action.