The rheological properties of pulps during acetylation process were discussed by using the rotationalviscometer. Cotton linter, commercial wood pulp for acetyl-cellulose and Viscose, purified wood pulps which were treated by hot alkali, cold alkali or acid hydrolysis, and pentosan were used. The rheological properties which were estimated from their rheogram is different by pulps respectively. And viscosities of their acetylation products were also examined.
Higher reactive pulps for acetylation changes, generally, their flow properties from non-newtonian flow to Bingham flow at early stage of acetylation than poorer one. Cotton linter changes most rapidly his flow properties and also have lower apparent viscosity of acetylation mixture than any pulps., But wood pulp which was hydrolyzed with mild condition and xylan do not change their non-newtonian flow properties during acetylation. And also wood pulp which was mercerized and then hydrolyzed with hard condition, did not exhibit the non-newtonian flow and always took a Bingham flow from beginning to end.
From these results, it seems that this difference of rheological behavior between cotton linter and wood pulps may depend upon the difference of their fine structure and the presence of non-cellulosic materials in them. And on account of these differences wood pulp may take a poorer dispersity of his acetylation bath.
This poorer dispersity of the acetylation bath of wood pulp causes higher viscosity than cotton linter for their accetylation products in the same solvent. It is said that wood pulp has a higher viscosity ratio (27%/7%) than linter. This difference of their viscosity ratio may depend also upon the poorer dispersities of wood pulps in the acetylation mixture.

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1.Chainlength of xylan extracted from ground-up beech wood was determined with the method of cuprammonium-viscosity. It was observed when the xylan concentration was over 5gr. per liter, the viscosities of cuprammonium solution were not variable with velocity gradients (Table 2) and composition of cuprammonum solution (Table 1) but if the concentration was under 5gr. per liter, the variation of viscosity was much greater. So the viscosity must be measured at the xylan concentration between 5gr. and 10gr. per liter. (See Table 1).
2. Xylan was easily hydrolysed by hot dilute hydrochloric acid solution but fairly resist oxidation in cold concentrated alkali state. (Fig. 2, Fig. 4). Its uniformities of chainlength were thought to be increased by hydrolysis. (Fig. 2, Fig. 4). The condition of xylan dispersion in the acid liquor at the earier stage of hydrolysis might considerably change yields, chainlength and polymolecularity of xylan hydrolysed.
3. Chainlength of non-resistant xylan extracted from pulp were determined . (Table 3). 4. Three series of experiments were undertaken to investigate the influences of xylan chainlength for viscose process. Xylan with different chainlength were added to aged alkali cellulose before xanthation. (Table 4, 5)
Viscosities, Hottenroth numbers and transparences of viscose in each series were determined and compared each other.
It was observed that xylan with short chainlength were less influenced to properties of viscose than that with long one, as compared with results of our former investigation. (H. Asaoka & K. Kudo : J. Chem. Soc. Japan, Ind. Chem. Section, 56 (1353) 455).
But in short chainlength xylan such as degree of polymerization 60 and 20, differences between them were very small.
It might be considered the shorter one had much effect upon viscose properties. (Table 6, Fig. 5, 6, 7).

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The I. G. T. Printability Tester is a miniature cylinder press, which operate at accelerating speed .It is designed by Instituut voor Grafische Tecknick TNO, Holland.
We have carried the test of picking registance about art paper and examined the conditions of picking registance, printing difference of the both side, and relation of directional properties of paper.
On the test, we used pendulum Pe, attachment A and B. Pe is falling pendulum weight, max speed is 230ft/min. A and B are spring load driving, the former is 500ft, imin at max speed, the latter is 750ft/min at max speed.
Ink for testing paper is S. G. medium of Dainihon-ink.
It is concluded, (1) at the temperature 20-30·C, S. G ink is stronger than the standard, (2) by S. G ink, data of picking registance increase to up-wards curve line, according to temperature. (3) when inking time is long, decrease picking registance as linear, (4) kinds of spring tension, 25kg, 35kg and 50kg, gave the same results.
(5) Twelve strips of covering are suitable for the test. (6) Using the same sample, three kinds of printing speed are not the same result between each. Pe>A>B
(7) About the inking film, when it is printed parallel to machine direction, moreink cause strong picking registance. (8) The parallel printing to machine direction are stronger than cross direction on both sides of paper.

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