Recently although a large quantity of corrosion-resistance alloy is required for the chemical industry and others, the Nickel production in this country is very poor at the present time. Therefore, the requirement of Nickel always cannot be filled. To economize this material and produce a lower-price stainless steel, we studied the manufacturing method of stainless clad plate and its qualities.
Base metal of stainless clad plate is mainly low carbon steel, and clad metal is 18% Chromium and 8% Nickel type austenitic stainless steel.
As the results of various tests, it is recognized as follows : -
1. Of many manufacturing methods, the casting method is the most suitable for mass-production because of easiness of working and the lowest cost.
2. In its manufacture, finishing of contact face in both metals, heating time or reduction ratio do not affect the contacting strength of clad plate. For convenience of making, reduction ratio can be fixed properly as about 3-10.
3. The tensile strength of clad steel generally agrees with the value, calculated from the thickness ratio between clad metal and base metal layer. Nevertheless the endurance limit of clad plate is far higher than the calculated limit.
4. The thermal conductibity of clad steel is considerably improved compared with the mere stainless steel.
5. When the clad plate is heated, both metals diffuse mutually in contact face and consequently contacting stress increases. On the contrary, there arise some warp which is attributed to the difference of thermal expansion, and it grows up greatly by heating up to the transformation of mild steel. When heating is necessary, it is desirable to make the temperature about 600°C. To avoid any distortion to arise in heated clad plates, the double-clad plate is recommended.
6. In the weld joining of clad steel plates an unbroken corrosion-resistant surface must be maintained. There is no difficulty in welding processes.
7. Clad plate can be cut easily by oxy-acetylene gas with the backing steel on top and incline the torch at proper tip angle from the vertical toward the direction of cut.

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When the resin are saponificated by Na₂CO₃ with high temperature and long time, there appears wrong color in the resin soap, and remains unfavourable color in the paper when are used as sizing matter.
We are carried several experiments about to avoid their color. First, we recognized that short time cooking by NaOH with high temperature was effective to avoid contamination and at the same time adding Superite (Sodium Sulfoxylate formaldehyde) with NaOH was more effective. Namely, Superite are decomposed to SO₂ and CH₂O at about 100°C, these strong reduction power are active to avoid wrong color. This Chemical is alkali side, so that sizing agent are not injured.
We got the following formula in the experiments as test method :
resin : color number 60-125
NaOH : about 10% for resin
Superite : 50% for resin
Liquor ratio : 1 : 1 (for solid)
cooking time : 1 Hr.
The size from these conditions are approximately same grade compare with pale color resin (color number 15)
As other chemicals, Na₂SO₃ are not effect on bleaching power and H₂O₂ NaCLO injures size agent.
On low temperature saponification, Delthirna method are effective to pale grade color resin to more prevent contamination of paper. But of all experiments, most effective method was Superite method in high temperature with short time cooking.

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Neutral sulphite semi-chemical pulps of beech (Fagus crenata Blume) were made with yields ranging from 60 to 72%. The cooking liquors used in this test were : sodium sulphite liquor with no buffer and sodium sulphite liquors with such buffering agents as sodium carbonate, sodium bicarbonate and calcium hydroxide. The results of these digestions were compared with each other in point of physical and chemical properties of pulps, and then the effects of these buffering agents on pulp properties were closely studied. The results obtained were as follows :
(1) The value of buffering agent in cooking increased as its alkalinity became stronger.
(2) As yields of crude pulps increased total cellulose contained in the pulps decreased and the lignin contents increased.
(3) With respect to the affection of buffers on values of total cellulose per lignin (each based on the wood), it was indicated that when calcium hydroxide, sodium bicarbonate and no added buffer were used, the pulps were more or less similar, but the use of sodium carbonate buffer resulted in a lower value at the similar yield of crude pulp. And these values derceased according to the rate of increase in pH values of the spent liquor.
(4) The brightest pulps were obtained when pH value of the spent liquor was somewhere from 7.2 to 7.7 with the aid of the abovementioned buffering agents.The highest brightness of the pulp was attained when no buffer was added to the cooking liquor. The addition of a limited quantity of calcium hydroxide and sodium bicarbonate proved next best, while sodium carbonate brought forth the lowest in the brightness of the pulp.
(5) Unbuffered pulps would be considered advantageous for fully bleaching because of the lowest chlorine number, considering the relations between crude pulp yields or lignin contents and chlorine number.
(6) When several pulps were treated by the one-stage calcium hypochlorite bleaching process, the bleached pulp yields were from 66 to 68%, as against the quantity of wood used. The brightness of the pulp obtained therefrom 55 to 65%.
In conclusion, considering total cellulose, lignin contents, chlorine number, brightness, extracted resin and the pulp strength, I found out that the uubuffered pulp was the best and that those pulps obtained with calcium hydroxide, sodium bicarbonate and sodium carbonate fell off in point of properties in the order mentioned.

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Several experiments have been made to reseach the relations between chip characteristics......chip length, moisture content of chips and rotten woods and qualities of the sulphite rayon pulp from the coniferous woods.
The longer chips used, the cooking time lengthens to some extent, and we have higher pulp yield at same Sieber No. and slightly lower alpha cellulose content at same relative viscosity. But their differences are rather neglegible small in the rayon pulp range. We prefer to use the relatively shorter and uniform chips in order to cook the sulphite rayon pulp.
The difference in moisture content of chips in commercial circumstances hardly effects to sulphite cooking velocity. It is almost sure that the penetration of cooking liquor into wet chips is faster than in dry chips. We have gained the pulp with higher yield and slightly lower alpha cellulose content from extremely wet chips. We are not anxious about inuniformity of the sulphite pulp from the deviation of the moisture content of chips
The sulphite process very hardly delignified from the rotten woods, in comparison with easily hydrolysed the carbohydrates. At the same Sieber No. pulps from the rotten woods have considerably lower yield and alpha cellulose content in proportion to their rotten sections. We must keep away from even small amount of the rotten wood chips to enter into the digester.

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1) 碎木機用500HPと300HP電動機の周圍温度が生産量に及ぼす原因を探究した。2) 7.8.10.11の4ケ月の周圍温度と負荷の變化による電動機の温度を寒暖計法により測定した。3) この500HP電動機は年間定格電流84Ampにて運轉出來得ざる事實が明瞭化した。4) 300HP電動機は年間周圍温度は考慮しなくてよい。5) 負荷の變化による生産量は第四圖に示した。6) 電動機の負荷による温度の關係を第三圖に示し檢討を容易にした。7) 500HP電動機に關する運轉成績よりチップ生産量の増減と改修の事實を明瞭化した。

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