Packaging container for transporting ceramic substrates

1. A packaging container for transporting a plurality of ceramic substances, the packaging container packing a ceramic substrate set composed of the plurality of ceramic substrates that are stacked, the packaging container comprising:

a bottom portion having a rectangle; and

four side portions connected to four edges of the bottom portion respectively, wherein

side protrusions having a height of 2 mm or more facing inward are provided to at least two side portions facing each other among the four side portions such that the side protrusions contact the ceramic substrate set and hold the ceramic substrate set as a unit,

the bottom portion is provided with a bottom protrusion having a height of 2 mm or more facing inward such that the bottom portion contacts the ceramic substrate set and holds the ceramic substrate set as a unit, and

wherein the packaging container is configured to have a size relative to a size of the ceramic substrate set such that the ceramic substrate set presses against the packaging container due to deformation of the ceramic substrate set during packing of the ceramic substrate set in the packaging container.

2. The packaging container according to claim 1 , wherein

the ceramic substrate set is stored such that outer surfaces of the two ceramic substrates face two opposite side portions among the four side portions respectively,

each of the two side portions is provided with two or more rows of side protrusions extending continuously in a depth direction as the side protrusions, and

two or more rows of bottom protrusions are provided on the bottom portion as the bottom protrusion, the two or more rows of bottom protrusions extending continuously in a direction from one side portion to the other of two opposite side portions among the four side portions.

3. The packaging container according to claim 1 , wherein

the ceramic substrate set is stored such that an outer surface of the ceramic substrate at one end faces the bottom portion, and

two or more rows of side protrusions extending continuously in a depth direction are provided on each of the four side portions.

4. The packaging container according to claim 3 , wherein two rows of bottom protrusions are provided on the bottom portion as the bottom protrusion, the two rows of bottom protrusions extending continuously in a direction from one side portion to the other of the two opposite side portions among the four side portions.

5. The packaging container according to claim 3 , wherein two rows of bottom protrusions are provided on the bottom portion as the bottom protrusion, the two rows of bottom protrusions extending continuously in a direction from one side portion to the other of two opposite side portions among the four side portions, and two rows of bottom protrusions are provided on the bottom portion as the bottom protrusion, the two rows of bottom protrusions extending continuously in a direction from one side portion to the other of the other two opposite side portions among the four side portions.

6. The packaging container according to claim 3 , wherein two rows of bottom protrusions are provided on the bottom portion as the bottom protrusion, the two rows of bottom protrusions extending intermittently in a direction from one side portion to the other of two opposite side portions among the four side portions.

7. The packaging container according to claim 3 , wherein one row of bottom protrusion is provided on the bottom portion as the bottom protrusion, the one row of bottom protrusion extending continuously in a direction from one side portion to the other of two opposite side portions among the four side portions, and one row of bottom protrusion is provided on the bottom portion as the bottom protrusion, the one row of bottom protrusion extending continuously in a direction from one side portion to the other of the other two opposite side portions among the four side portions, and

the two bottom protrusions intersect at a nearly center of the bottom portion.

8. The packaging container according to claim 7 , wherein, the bottom protrusion includes a protrusion formed in a rectangle along an edge of the bottom portion.

9. The packaging container according to claim 1 , wherein

the ceramic substrate set is stored such that an outer surface of the ceramic substrate at one end faces the bottom portion, and

one bottom protrusion having an area ratio of 25% or more to a total area of the bottom portion is provided to the bottom portion as the bottom protrusion.

10. The packaging container according to claim 1 , wherein at least one of the bottom protrusion and the side protrusions of the at least two opposite side portions protrudes in a semicircular shape or a U-shape.

11. The packaging container according to claim 1 , wherein the four side portions have a shape that stands perpendicular to the bottom portion.

12. The packaging container according to claim 1 , wherein the four side portions are tapered such that an opening expands with respect to the bottom portion.

13. The packaging container according to claim 1 , wherein an outer frame forming an opening is formed with a flange substantially parallel to the bottom portion and outward.

14. The packaging container according to claim 1 , wherein a material of the packaging container for transporting ceramic substrates is plastic.

15. The packaging container according to claim 1 , wherein the ceramic substrate is a silicon nitride substrate or a silicon nitride metal bonding substrate.