I prepared hydrotropic pulps (HP) and neutral semichemical pulps (NSCP) from Japanese red pine (Pinus densiflora) and Japanese oak (Quercus serrata).
The results are as follows.
1. There are no difference in four excellent hydrotropic reagents for cooking (H). So, xylensulfonic soda shall be used as it is the most inexpensive.
2. As the concentrations are 25% or less, cooking abilities of H are markedly dropped. They are fairly increased as the concentrations of H are increased from 35% to 45%. But, as the parts of 45% reagents are deposited at room temperature, 35% reagents shall be generally used.
3. The chips of 1mm x 3mm x 3mm are superoir than the wood powders for the cooking samples.
4. Japaneses red pine cannot be cooked by H. Lignins of the cooked materials by H are much than those of original samples inspite of using of any kinds and any concentrations of H. Longer the cooking times are, higher the lignins of cooked materials and less holocelluloses of them will be.
5. Japanese oak can be cooked by H, but the cooked materials having less than 5 to 10% lignin will not be able to obtain. Longer the cooking times over this lignin content are, reversely lignin of cooked materials increase rapidly and holocellulose of them decrease distinctly.
6. The same yields of cooked materials will be obtained at the temperature of 150 to 180°C in the same lignin, content.
7. Using Japanese oak, the yields of NSCP are 71% and those of HP are 55% in the same lignin content of 10%.
8. Therefore, hemicelluloses of much quantities shall be dissolved into the liquor of H, and the wased liquor of H cannot be reconverted to original liquor by such dilutions, filtrations and concentrations as Mckee's theses.
9. Two step cooking process including prehydrolysis of H cannot be completely considered economically.

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Sizing is achieved by adding Petroleum Resin first to the pulp in beater and then, when it is well mixed with about 20% of precipitated calcium carbonate in the pulp, aluminium sulphate (“ alum ”). It will be observed the perfect of sizing on the tissue paper, or the test result of K.B.B Sizing test by sugar solution is indicated about 50 seconds, Stockigt method was 5 seconds. (40g/m²)
Influences affected by the fluorescent whitening agent to the sizing effect were investigated.

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According to the information of the Japan Tappi, in Japan, there are three systems for the refining procedures in semichemical pulping. These systems are as follows :
1. Single-pass refining system.
2. Double-pass refining system.
3. Fiberizing and refining system.
This paper deals with the results of studies on the effects of fiberizing or refining variables ineach system for refining procedure.
In these experiments, beech wood chips cooked by the neutral sodium sulphite solution were refined in a 12 in. single-rotating mill (Spraut Waldron refiner).
The following results were obtained.
1. In the single-pass refining system and the primary refining step at the double-pass refining system, it was found that the unit refining energy was dependent on the refining temperature. The screenings were influenced by the plate separation and the refining temperature. When the operation was treated at high refining temperature, unit refining energy was decreased, but the screenings were increased. But then, screenings were decreased by the narrow plate separation at high refining temperature.
2. In the fiberizing and refining system, it was found that the total energy consumption per unit of feed was dependent on the feeding rate at the refining step, and the unit refining energy was dependent on the plate separation, the refining consistency, and the feeding rate at the refining step.
3. In the fiberizing and refining system, the freenesses and screenings of refined pulps were influenced by the following factors : plate separation, feeding rate, and refining consistency at the refining step. Therfore, refining at the narrow plate separation, low feeding rate, and low refining consistency made it possible to reduce freeness and screenings of refined pulps.
4. In the fiberizing and refining system, the physical properties of refined pulps were influenced by the plate separation at the refining step. As the plate separation was decreased, the physical properties of refined pulps were improved.
5. From these relationships (2, 3, 4), it was clear that there were constant relationships among the unit refining energy, freeness of refined pulps, and physical properties of refined pulps.
As the unit refining energy was increased, the freenesses of refined pulps decreased. The bulk density, bursting strength, and tensile strength of these pulps rose as the freeness was decreased.
6. The physical properties of refined pulp were improved by beating except the tear strength.
7. It was not distinguished that the physical properties of beaten pulps differed with the beating methods except the fiberlength distribution, bulk density, and specks in a hand sheet.

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