In the second and the third reports, the recent improvements and developments of coating methods for the production of printing papers were introduced.
In this report I would like to introduce some of the literatures showing the investigations on high-solids coating from the viewpoint of color formulation.
I would also like to take this special opportunity to comment on the relationship between the shape or the particle size of the color pigments and the color rheology, and further how the color rheology is changed when other pigments are mixed.

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Fluidized bed boiler (F.B.B.) and highly loaded coal water mixture (CWM) have recieved considerable world wide attention as prospective new coal utilization technologies.
The main advantages of FBB are considered as follows. FBB can burn a variety of fuels such as low grade coal including sedimented waste, and very high degree of desulfurization can be achieved directly in the combuster.
It has already been commercialized in industrial use, and 50 MW demonstration plant for verifing utility use are under construction.
Highly loaded CWM contains 60 to 75% coal suspended in water. It is ground into desirable particle size distribution somewhat finer than the standard pulverized coal grind and a complex chemical additive system gives the preferable CWM properties as liquid fuel.
Furthermore combustion test programms undergoing show excellent combustion characteristics because CWM include a lot of fine coal particle and water. So it is greatly expected that could be used as a substitute liquid fuel for heavy oil.

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The following is the explanation on the development process, technical features and the economical effectiveness of the Light-Weight Keyless Rotary Letterpress Printing Press, which was awarded a prize as one of the superior energy-saving machinery and equipment for the year 1984 from. The Japan Machinery Federation :

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Nayoro Mill started up in 1960 as “Teshiogawa Paper mfg. Co., Ltd.” The company name was changed in 1979 as “Hokuyo Paper Co., Ltd.” by reason of join with “Kitami pulp mfg. Co., Ltd.” This mill has 3 paper machines and 2 pulping processes and its productions are 400 tons per day of corrugating medium and 150 tons per day of paper board.
The mill site covers an area of about 225, 000 m² and the mill employees count about 200.

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Physical and mechanical properties of paper are obviously influenced by sheet geometry. In particular, local sheet density variation, if present, may cause measuring values of various kinds of tests to be scattered. Wet pressing is one of the most critical processes governing sheet density.
Thus, distribution of pressure applied on wet web during wet-pressing was investigated first using pressure sensitive plastic films. Red color intensity and patterns appearing on the films under standard conditions was compared with that in the absence of blotter papers. The comparison showed that the web was pressed unevenly with the standard method, and that the non-uniformity of press may be attributable to the presence of blotter papers, which have by nature a very uneven mass distribution.
In contrast, it was revealed that the local variation of sheet density calculated from both thickness and basis weight variation profiles on a scanning line was fairly small. The result indicates that after pressure was removed the collapsed fibers in the wet web began to expand toward the original shape in the presence of a relatively large amount of water. The recovery of bulk occurred independently of the degree of uneven pressure in the wet-press process.

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The best strain (Coriolus hirslits IFO 4917 (in this paper, abbreviated as WR 28)) was screened out among 48 strains of white-rot fungi. The optimum pH and the optimum temperature were pH 4 and 33-36°C, respectively. The strain WR 28 was capable of decolorization of lignosulfonate. And lignins of hardwoods, especially poplar (Populus trichocarpa T. & G.) were considerably delignified, however, soft woods, used in this experiment were not delignified except Japanese red pine (Picea resinosa Ait.). With non-woods, the lignin of rice straw (Oryza saliva L.) was not decomposed at all. For manila hemp (Musa texlilis Nee L.) and bamboo (Phylloslachys Sieb. el Zucc.), the degrees of delignification were high (39.0% and 22.0%, respectively, for WR 28). As for WR 28, Bavendamm reaction was positive with several phenols such as Guaiacol, Benzidine, ο-Anisidine, α-Naphthylamine, 2, 5-Xylidine, o-Toluidine and Pyrogallol.
Lignins of poplar and bagasse (Saccharuni officinarum L.) were decomposed to a degree of ca. 63% and ca. 80%, respectively, for 2 months.

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Studies were carried out on bleaching of Sugi PAP with Hydrogen Peroxide-Alkaline (Pa) solution. The Pa solution was a mixture of water, hydrogen peroxide (1-7% on od. PAP), sodium hydroxide (as Na₂O 1-10% od. PAP), and small quantities of auxiliaries (DTPA and AQ), the liquor ratio of the mixture to PAP being 10 l/kg.
Pa treatment made unbleached pulps into lower kappa no. and slightly higher brightness pulps (Hunter brightness 49%, kappa no. 15). Especially suitable quantity of sodium hydroxide (as Na₂O 2-3% on od. PAP) was effective for bleaching. Pa two stage treatment gave semi bleached pulp (Hunter brightness 59%, kappa no. 11) without chlorine. Pa Pa H three stage sequence gave a high brightness bleached pulp (Hunter brightness 78%) with small quantity of hypochlorite (as available Cl₂ 3% on od. PAP).

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