Impact absorber and packaging material

Abstract

An impact absorber includes a three-dimensional structure. The three-dimensional structure includes a closed top surface, an open bottom, a hollow inside, and a recess. The recess is disposed within an outline of the top surface.

1 . An impact absorber comprising a three-dimensional structure, the three-dimensional structure including:
 a closed top surface;   an open bottom;   a hollow inside; and   a recess within an outline of the top surface.   
     
     
         2 . The impact absorber according to  claim 1 , further comprising another recess within the outline of the top surface. 
     
     
         3 . The impact absorber according to  claim 1 ,
 wherein the recess has a U-shape, a C-shape, or a V-shape in cross section.   
     
     
         4 . The impact absorber according to  claim 1 ,
 wherein the recess has, in top view, a polygonal shape, a circular shape, or an outer shape in which curved lines or straight lines are connected with each other in a wave shape.   
     
     
         5 . The impact absorber according to  claim 1 ,
 wherein a depth of the recess is equal to or greater than twice a thickness of the impact absorber and equal to or smaller than half of a height of the impact absorber.   
     
     
         6 . The impact absorber according to  claim 1 ,
 wherein a distance between the outline of the top surface and the recess is greater than twice a thickness of the impact absorber and equal to or less than half of a length of the outline of the top surface along a same direction as the distance.   
     
     
         7 . The impact absorber according to  claim 1 ,
 wherein the impact absorber is a prismatic outer shape or a cylindrical outer shape.   
     
     
         8 . The impact absorber according to  claim 1 ,
 wherein the impact absorber comprises molded pulp.   
     
     
         9 . A packaging material comprising the impact absorber according to  claim 1  at at least one position. 
     
     
         10 . The packaging material according to  claim 9 ,
 wherein the top surface of the impact absorber is disposed at a position to contact on an object to be packaged.   
     
     
         11 . An impact absorber comprising a three-dimensional structure,
 the three-dimensional structure including:
 a closed top surface; 
 an open bottom; 
 a hollow inside; and 
 a groove crossing the top surface, the groove having a depth equal to or greater than twice a thickness of the impact absorber and equal to or smaller than one fifth of a structural height of the impact absorber. 
   
     
     
         12 . The impact absorber according to  claim 11 , further comprising another groove crossing the top face,
 wherein said another groove has the depth equal to or greater than twice the thickness of the impact absorber and equal to or smaller than one fifth of the structural height of the impact absorber.   
     
     
         13 . The impact absorber according to  claim 12 ,
 wherein the groove is orthogonal to said another groove.   
     
     
         14 . The impact absorber according to  claim 11 ,
 wherein the groove has a U-shape, a C-shape, or a V-shape in cross section.   
     
     
         15 . The impact absorber according to  claim 11 ,
 wherein the impact absorber has a prismatic outer shape or a cylindrical outer shape.   
     
     
         16 . The impact absorber according to  claim 11 ,
 wherein the groove has, in top view, an I-shape or a cross-shape including a continuous line connecting straight lines, a continuous line connecting curved lines, or a continuous line connecting a straight line and a curved line.   
     
     
         17 . The impact absorber according to  claim 11 ,
 wherein a width of the groove is equal to or more than twice a thickness of the impact absorber and less than one third of a width of the top surface of the impact absorber.   
     
     
         18 . The impact absorber according to  claim 11 ,
 wherein the impact absorber comprises molded pulp.   
     
     
         19 . A packaging material comprising the impact absorber according to  claim 11  at at least one position. 
     
     
         20 . The packaging material according to  claim 19 ,
 wherein a top surface of the impact absorber is disposed at a position to contact on an object to be packaged.