The properties of carboxyethylated polyvinyl alcohol (CEP) coating colors and coated paper were studied, and the correlations between high shear rheological properties and actual coating trials on a pilot equipment were discussed.
It was found that the colors had high shear rheological properties desiable equivalent to those of starch colors and casein colors, and the colors could be successful applied by blade, air knife and roll coaters to produce smooth, pattern-free coatings, while the flow properties of the unmodified PVA colors were less than those of CEP colors and they showed severe patterning.
In addition to good rheological properties of the colors, the qualities of the coated papers were satisfactory for printability tests, and especially, ink receptivity of the papers was superior to that of PVA/clay, starch/clay and casein/clay coated papers.

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キシレンスルホン酸やカルボン酸のような芳香族酸の塩類の高濃度溶液を使ってパルプを製造しようとする, いわゆるハイドロトロピック蒸解 (以下HCと略記) について, 前報では主としてチップからリグニンが溶出するさいのリグニン溶出機構を中心として検討した結果を報告した¹⁾ 。
従来, 代表的なハイドロトロピック剤 (以下HRと略記) として, キシレンスルホン酸, トルエンスルホン酸, サイメンスルホン酸および安息香酸のそれぞれソーダ塩が使用されており, 前報では新しくキシレンカルボン酸ソーダによる蒸解も併せ試みた¹⁾ 。ハイドロトロピック蒸解に限らず, 一般に化学パルプを得ようとするさい, 蒸解作業の主な目的は, 木材組織からリグニンを除去することによって, 繊維細胞の相互離解を容易にすることである。したがって, 蒸解のさい, チップからのリグニン溶出率が大きいほど, 蒸解後の解繊が手軽となり, リゼクトが少なく, 漂白性の向上が期待される。高いリグニン溶出率を持つ薬剤の開発や十分なリグニン溶出率を示し得るような蒸解条件の設定が注目されるのは, このためである。いままでのHCでは, リグニン溶出率が70～80%のHRが多く, 蒸解条件を吟味したとしても80%を大きく上回るものは少ない。前報で新しく合成したキシレンカルボン酸ソーダによる蒸解結果をみても, リグニン溶出率は従来のものより確かに向上したが, 依然として84～85%の線を越えることはできなかった¹⁾ 。
ここではリグニン溶出率に重点を置きながら, より強力なHR, つまりより高いリグニン溶出率を示し得る薬剤を, 前報¹⁾ で明らかにされたHRとして必要な性格づけを考慮しながら, 広い範囲にわたって, より多くの化合物のなかから見出そうと試みた。そのさいに得られたいくつかの知見を報告する。

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This paper describes the results of alkaline pulping of beech wood, which has been cooked by ammonium sulfite and ammonium hydroxide solutions. In series of cooking, liquor concentration, maximum temperature and cooking duration at maximum temperature were varied. Evaluation of pulpings were investigated by analysises of the residual lignin and pentosans in resultant pulps, bleaching and paper strength tests.
Summary of results are shown as follows ;
1) It was found that the best conditions for cooking were as follows :
Liquor composition : Ammonium sulfite 18%, Ammonium hydroxide 30%
Liquor to wood ratio 4.5 : 1
Maximum temperature 180°C
Time at maximum temperature 2hr.
2) Total pulp yield ranged from 55.8% to 64.6%. It was decreased with increasing sulfite-ion concentration. The pulp yield was increased rapidly in proportion to ammonium-ion concentration in the range of lower concentrations, but this relation was reversed over some ion concentration. This changing point was moved to the higher ammonium-ion concentration with increasing sulfite-ion concentration.
3) Residual lignin in pulps stood in the range of 0.89-6.90% (based on oven dry wood). The rate of delignification was proportion to [NH₄] [SO₃] ^3.016. The ability of delignification with sulfite-ion was about three cubed times as much as that of ammonium-ion.
4) The degradation of pentosans by cooking were controlled with increasing the concentration of ammonium-ion, but were activated with increasing the concentration of sulfite-ion.
5) Whiteness of bleached pulps were slightly lower than that of the ordinary bleached chemical pulps. In the case of well cooked pulps, decreasing of pentosans by bleaching was a little. The maximum decrement of pentosans was not exceeded about 4%. Yields of bleached pulps stood in the range of 53-56% (based on oven dry wood).
6) The strength properties of unbleached pulps were lower than those of the ordinary sulfate pulps, but those were improved by bleaching treatment. The strength properties of bleached pulps were similar to those of the ordinary bleached sulfate pulps. The pulps cooked by 18% ammonium sulfite and 40% ammonium hydroxide solution showed best strength properties.

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ディスクレファイナーにおける処理原料の濃度の高低はパルプの品質並びに処理量に対する大きな変動の要因であるが, これに対応するプレートパターンの選定のためにはプレート刃面のテーパー量の適否が極めて重要な要素である。
更に濃度に対するテーパー量の相関的数値については一般的平均値を示すことは出来るが, パルプの材種, 前処理の度合, その他に基づく複雑な条件を考慮すれば各事業所毎にその実績を基礎として決定せらるべきである。
中間濃度磨砕についてはレファイナー機構の大幅な改造が期待されるが, プレートについても多くの問題点が考えられ今後の大きな課題である。

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The use of fluorescent whitening dyes with food paper container or packing material and sanitary napkin for medical supplies is forbidden by the Food Sanitation Law in Japan.
The ground of this law is introduced ; the toxic experimental results and its opinions were introduced.
A measurement of fluorescent strength by colrimeter and the relationship between additional amounts and florescent strength, stripping method of fluorescent whitening paper were studied.
The retention of fluorescent dyes in paper is 31%.

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