The purpose of these tests were to decide the most suitable ratio of length to width (L/W) of Clupak paper bag and Normal Japanese kraft paper bag respectively.
In these tests, the paper bags used were all small type of them.
1) In Face & Back drop test, the most suitable ratio of L/W of Normal kraft paper bag was from 1.75 to 2.00 and that of Clupak paper bag was 1.25.
For one of the reasons, it seemed from the state of rupture of the bag dropped that the higher the ratio was the heavier the main impact energy might add to the lengthwise direction of the bag.
From the above assumption, Clupak paper bag was stronger by increasing the ratio because the toughness of M.D. was larger than that of C. D. of the paper, and while Normal kraft paper bag was stronger by decreasing the ratio because the toughness of C.D. was larger than that of M.D. of the paper.
2) Butt drop was not tesied. But, in this case, it was assumed that Clupak paper bag and Normal kraft paper bag would be stronger together by decreasing the ratio of L/W of the bag.
Therefore, the most suitable ratio of L/W of Clupak paper bag might exist in 1 .25 in the case of the both types of drop test.
3) It could be stated from the results of drop test that the rate of the strength of Clupak paper bag to Normal kraft paper bag was 1.82.1 times in the ratio=1.001.25, 1.51 .6 times in the ratio=1.50 and 1.2 times in the ratio=1.752.00.
4) In the most suitable ratio of L/W of each paper bag, the strength of Clupak paper bag to Normal kraft paper bag had 1.41.5 times.
5) Theoretical explanations about these results of the experiments mentioned above are carried out now by testing the decrease rate of the strength properties of paper during dropping the bag.