The lignin content of the red pine wood extracted with alcohol-benzene solvent and of the pulps prepared from the extracted red pine wood by neutral sulfite process, are determined by sulfuric acid in several concentrations. Then their methoxyl and sulfur contents are determined, and the following chief results are obtained:
1. To determine the lignin content of red pine wood, using 72% optimum concentration of sulfuric acid it requires 4 hrs at 20°C
2. The methoxyl contents of the prepared lignin from red pine pulps are always smaller than that from red pine wood, and the higher the degree of pulping the smaller methoxyl content of the prepared lignin is obtained.
3. It is estimated that the measured methoxyl amounts of red pine wood or pulps are not all due to their lignin contents, but some to their carbohydrate parts.
4. On the process of lignin determination of sulfite pulps by 72% sulfuric acid, considerable amounts of sulfonic radical of lignosulfonic acid in the pulps are splited.
5. The higher the degree of pulping the more strongly the concentration of sulfuric a_??_id effects on the analysed lignin value.

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Beech wood was cooked with the sulfite liquor (total SO₂, 6.92%. combined SO₂, 1.52%. max. temp. 140°C) for 10.5, 12 and 12.75 hours, and three unbleached pulps were obtained. The pentosan, lignin, degree of polymerization and its distribution of the pulps were determined. Non-uniformity coefficient was obtained by comparing DP_w (viscosity average) with DP_n (from osmotic measurernent of the acetone solution of the nitrate). The results were as follows.
1. With increase of time for cooking, the lignin content decreased rapidly but the decrease of pentosan content was not so considerable. The increase of the low DP portion of the pulps was marked.
2. Non-uniformity coefficient obtained by the measurements of viscosity and osmotic pressure showed decrease(0.89, 0.70, 0.54) with increase of time for cooking. This result was contradictory to the fact that the marked increase of the low DP portion was observed at the later stage of cooking. This would be due to the diffusion of the low DP portion through the membrane in the osmotic cell.

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The levelling effect of ideal drafting is theoretically studied. After some analysis it is concluded that the coefficient of variation of fiber end density in slivers may be diminished by drafting, if the frequency distribution φ(x) of velocity change point of floating fibers in drafting field does not vary with time. Assuming that the distribution φ(x) is normal and uniform, it is shown that the diminution of coefficient of variation in density of slivers is larger in higher drafting, wider distribution of fiber velocity change point and shorter term variations. On a further consideration, it is suggested that the levelling effect like this may be found in other spinning processes besides roller drafting, and it may be possible to diminish a particularly remarkable irregularity by using process in which the distribution φ(x) is proper for its wave length and the draft apparatus which has wide distribution of fiber velocity change point may be rather effective for diminishing thickness irregularities.

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In the previous paper we discussed the problem of the simple fibre motion in the roller draft field, but the practical behavior of the fibre is not so simple as we have shown previously.
Therefore the experimental result with respect to the draft curve does not correspond with the theoretical result.
In this paper to overcome the difficulty, we separated the practical fibre motion from the velocity distribution of the draft field. we assumed that the velocity distribution is the mean velocity which depends on the practical fibre motion.
In this case the practical fibre motion is regarded as the two velocity groups, one equal to the linear velocity of the front roller and the other one equal to that of the back roller, as done by Foster.
Then we induced the generalized sliver diagram and the draft curve after the Goodings method.

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Outer and inner constructions, having important effects upon the quality of woven fabrics, are completed by the behaviors of the warp & weft yarns during the following weaving periods;
(I) Behaviors of the warp & weft yarns during the weft inserting motion.
(II) Behaviors of the warp & weft yarns during interlacing period which is effected by the beating motion.
(III) Relaxation of the warp & weft yarns which built the fabric constructions at an equilibrated state being not influenced by the beating motion.
The calculation concerning the behaviors of the warp & weft yarns when the reed leaves the cloth-fell and while the reed is beating the cloth-fell during the above-mentioned period (II) is shown in this report.
When the reed leaves the cloth-fell, the equilibrated position of the last weft yarn inserted is calculated by the following equation; where β (=α₀): Shedding angle (q. v. Fig. 1) α₁: Interlacing angle (q. v. Fig. 1) μ: Frictional coefficient between warp & weft yarns
Then the interlacing angle of the weft yarn beaten at the cloth-fell before n beatings, is calculated by the following formula;
Moreover, while the reed beats the cloth-fell, the interlacing angle concerning the weft yarn beaten last is calculated by the following formula too; where T₀: Tension of warp yarn before the reed beats the cloth-fell T₀′: Tension of warp yarn increased owing to the beating k: T₀′/T₀ And, for n, after the weft yarn last beates up the cloth-fell, we obtained the following equation:
Therefore, by n>1 we can calculate from the equation (2)-(4) easily the interlacing angles α₁, α₂, ……α_n and α₁′, α₂′, ……α_n′ with which one warp crosses each weft before and after each beating, when numerical values of β, k and μ are given
Then, comparing α₁, α₂, ……α_n with α₁′, α₂′, ……α_n′, we observed the theoretical interlacing phenomena between the warp & weft yarns, and established a guide for future experimental studies.

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Polyvinyl alcohol (P. V. A.) fibre without heat treatment was swollen in water, methanol, or their mixture at room temperature and then, after replacement of medium, treated with Tetramethylene Diisocyanate (T. M. D.) in sealed tube. Nitrogen content was estimated for treated sample fibre.
The affections of treating conditions upon the degree of reaction were examined. Addition of T. M. D. on fibres is greatly affected by the degree of swelling and the kind of solvent used at the reaction (Benzen, Dioxane, Pyridine or their mixture.) As the reaction medium, Pyridine was most favourable.
T. M. D. added on fibre was from 0.2 to 8 moles per 100 V. A. units. Upon the X-ray examination, formation of Polytetramethylene Urea was not found in fibre.

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Tenisle strength and elongation of P. V. A. fibres with various quantities of Tetramethylene Diisocyanate (T. M. D.) was examined.
It was found that the relation between their tensile properties and T. M. D. content is similar to that between the tensile properties and sulphur content in vulcanzied rubber. This phenomenon is probably due to Diurethane cross-linkage formed between P. V. A. molecules.
Among several series of the treated fibre swollen to various degrees in the pretreatement, the above tendency was more remarkable, where the swelling is greater. The less swelling, the less T. M. D. content gave rise to the effect of cross-linking.
Suitable heat treatment of the fibre, which is treated by adding a comparatively small amount of T. M. D. and fully swollen, improves appreciablly their tensile strength and hot water resistance.

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From the determination of transmission values of light through a tyrosin solution which is exposed to ultra-violet rays, and reflection values of light by a boiled-off silk which is also exposed to ultra-violet rays, the authors found a method to estimate the tendency to yellowing and browning that occures in a boiled-off silk when it is exposed to atmosphere.
After exposing silk samples to ultra-violet ray for respectively 1 and 48hours, the reflection value of samples at 380mμ and 480mμ was measured with a electric spectrophotometer, and obtained the following values:
where, Ref⁰_λ and Ref⁰_λ′ stand for reflections of rays at λ=480mμ and λ′=380mμ of those samples that had not been exposed to Ultra-Violet ray; and Ref¹_λ and Ref¹_λ′ stand for reflections at λ and λ′ after 1hr exposure to U. V. ray and lastly Ref⁴⁸_λ′ the reflection at λ′ after 48hrs exposure.
The comparison of these corresponding values with those of the standard silk sample gives the degree of yellowing and browning in a more quantitative way.

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Sample of silk fabric scoured under different condition were prepared, and their tendencies to yellowing and browning were examined. The authors also investigated a relationship between composition or construction of silk fibroin and yellowing or browning af a boild-off silk.
The yellowing or browning during scouring can be diminisehd by adding a reducing agent to scouring liquor. The liability to yellowing or browning after scouring has some relation with a destruction of peptide chaid in fibroin which occurs during scouring, and this destruction takes place more easily when the pH of liquor is higher.
From the results it can be deduced that a boild-off silk will not easily yellow or brown, if silk is scoured in a liquor of low pH, and in a neighbourhood of isoelectric point of silk by adding a reducing agent.

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