In the previous paper, it was shown that the yield of pulp obtained from beech wood, which was cooked by alkaline solution containing NH₄OH and (NH₄) ₂ SO₃, was higher than that of ordinary kraft pulp. (Pulp yield ; 64.655.8%, lignin content ; 6.90.9% based on wood)
This paper discusses the properties of the pulps in order to elucidate the reason for high yield. Chemical constituents and intrinsic viscosity of the pulps are given in Table 1. It has been shown that the degradation of holocellulose has been decreased successively with increasing the amount of NH₄OH in cooking liquor. The degradation of cellulose has been prevented by “stopping reaction”, which has been confirmed from the existence of C₆-metasaccharinic acid in the hydrolyzates of cellulose.
It is one of the reason for high pulp yield that the degradation of pentosans has been dropped rapidly by increasing the amount of NH₄OH in cooking liquor.
It has been supposed that aldonic acids consisted in cellulose-end groups was increased with increasing the amount of (NH₄) ₂SO₃, and acid hydrolysis of cellulose was proceeded successively.

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This paper presents some observations on the toxicity characteristics of the spent liquor from semi-chemical pulping comparing with that of kraft pulping. TLm (median tolerance limits) for 24 and 48 hr. exposure periods and MST (median survival time) was adopted for bioassay, and Himedaka (Aplocheilus latipes) and Medaka (Oryzias latipes) were used as test organisms.
The TLm-48 hr. value expressed by chemical oxygen demand for the neutralized SCP waste was 2, 340ppm, whereas that for KP waste was 755 ppm. This indicates that the toxicity of SCP waste is not so strong as KP waste.
The toxicity of SCP waste was comparatively stable. During the storage for several days, the toxicity of KP waste reduced day by day, while that of SCP waste was not reduced remarkably. This supports the feasibility of volatile toxicants such as methyl mercaptan and hydrogen sulfide for the KP waste.
The toxicity of SCP waste was not reduced by treatments of both the aeration and the irradiation of ultraviolet light. That of KP waste was, however, reduced considerably by each treatments. This difference was examined, and it is concluded that the suspended substance which appears after storage for certain period interfered the effectiveness of these treatments for SCP waste. The stability of SCP waste was considered to come in part from this interference of the suspended substance, which is made up mainly of xylose.

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Effects of polychlal fiber addition to Asbestos paper were studied.
The paper made of asbestos fibers and polychlal fibers showed good flame resistance without addition of any other fire retardants.
The paper was much improved in tensile strength, tearing strength, and folding endurance compared with ordinally asbestos paper. Drainage of asbestos stock was improved by addition of polychlal fiber.
Polychlal fiber used in this study was “Cordelan” manufactured by Kohjin Co.

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Synthetic pulp for papermaking may be manufactured by beating the fibers of polyvinylalcohol (the PVA) mixed-spun with starch or the fibers of polyolefins mixed-spun with PVA polymer.
Various papermaking tests were carried out with this synthetic pulp to obtain the following results.
1) The more the PVA or starch content in the fiber, the more easily can it be fibrillated and the better are the dispersibility and other properties for papermaking.
2) The PVA fibers, if pre-mixed with starch on spinning, can be made into paper by beating without mixing any other material such as wood pulp, wether the fibers have been subjected to only heat treatment or to both the heat treatment and formalization in their manufacturing process. The fibers heat-treated only may also be used as a bonding material.
3) If the beaten PVA fibers, heat-treated, are formalized to eliminate interfiber bonds, then the strength of the paper made will depend on only the tangle of the fibers and it can be estimated at a quarter of the whole strength of the same paper but not formalized.
4) Polyolefins can be converted into another synthetic pulp by means of flash-or mixed-spinning. This pulp can be made into synthetic paper, being mixed with wood pulp.
5) Hydrophilic synthetic pulp may be obtained by beating the thicker fibers that are produced by mixed-spinning the three polymers : polypropylene, polyethylene and polyvinylalcohol. Such synthetic pulp can be made into paper either by itself or by mixing wood pulp in any proportion, which will be, if calendered, not inferior at all in strength to the conventional paper of wood pulp

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In this new former, an air pressure ranging from about 0.05 to 0.1 psi is applied outside of the free surface of wet sheet on a conventional cylinder mould.
Predominent merits involved in this new method are discussed in this paper in contrast to the conventional and suction type formers as follows; the simplicity of the construction and operation, advanced speed and drainage rate, evening or leveling effect to the wet sheet, and the compacting effect to the sheet substance.

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