クラフト紙の物理的強度についての統計学的解析 (その一)

抄録

The present paper -was reported the results of statistical analysis which are obtained from the dataof the tests of physical strength done variously on the kraft papers.
It is the ultimate propose of this investigations to establish the function of discrimination for kraft.paper to be coincided with the practical intensity as they apply to bags.
However, with respect to relationship between the values of physical strength on the raw paper and the dynamical actions of paper bag under practical conditions are not only complicated but also to be attended with difficulties to do the analysis.
Firstly, in order to clear the above mentioned regards and for knowing the general tendency of strength values, it was necessary that the statistical data of phisical strength on the good number of kraft papers. According to these data, we have analysed mostly the individual correlationships among the values of each strength, and have done the functional indication of those relationships by the method of least squares. Moreover, calculating the unbiased estimate of population variance of the most probable values of its function for the true values which have to itself were sllown the confidence band of the each functions in a 5 percent level of significance.
In the analytical indications which we have tried are obtained the results as follows. It was found that to be related organically to among the individual physical properties of kraft paper, and also the relationships to be indicated mostly with the primary and exponential functions such as y=a+bx, y=ax^b or y=ab^x.
The regression formulas between the basis weight and the individual strength values are shown in Figs. from 1·1 to 1·6. And, the regression formulas of the machine direction to cross direction in the each strength value are shown in Figs. from 2·1 to 2·5.
Moreover, the regression formulas among the each individual strength are shown particularly in Figs.to 3·1 to 3·17. Jast as it is clearly in Figs. from 3·10 to 3·15, we could certify that the several regression formulas which are obtained after analyzing the data of dynamic tensile are shown smaller the precision error of regression with the individual strength than in the other cases. The dynamic tensile tester which we have used to this test is manufactured by TOY0 Testing Machine Industry Co.Ltd., it is a new tester for kraft paper (Photo. I).
Besides, in Figs. from 4·1 to 4·8, it shown that the relationships with the values of strength and its observation error (standard deviation) in the each physical test.
In addition, the paper sample which we have tested is a natural kraft of 54 kinds and an apporo ximate basis weight from 50 to 100 grams per square metre. For as the physical strength tests, mostly the tesile by Schopper type, burst, tear and the fold endurance by M. I. T method were tried with the Japanese standard for testing method of paper and pulp.