The sizing efficiency of pre-strained papers were measured by Stockigt and Cobb sizing test methods. It was found that the sizing efficiency of acidic-sized papers decreases with straining of sheet, while that of alkaline-sized papers exhibits a reverse tendency. Straining level also affects sizing efficiency. However, all these changes are within 10% of the sizing degree of the unstrained paper. Effect of the factors being affected by straining, such as paper thickness and porous structure, were studied on the basis of Lucas-Washburn equation. Analysis shows that the differences between alkaline- and acidic-sized papers could be interpreted in terms of the bonding forces between pulp fibers and sizing agents, and the uniformity of distribution of the sizing agents on the fiber surfaces.

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Wetting and penetration behaviors of paper with water were investigated by Bristow's test and newly developed ultrasonic attenuation method. Close correlations between the characteristic quantities determined by the two methods were confirmed with a series of test sheets of widely varied sizing levels, both for rosin sizing and alkaline sizing. The coefficient of correlation between wetting delays by the two methods was 0.92, with a proportionality constant of 1.07. The difference from the previous value for commercial papers was ascribed to the surface treatments.

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Interfacial electrical properties of the surface of nylon 6 fibers ungrafted and grafted with acrylic and methacrylic acid were investigated. The isoelectric point (ζ=0) shifted into acidic side with increase in the amount of grafting.
In neutral and alkaline solution, saturated values of ζ-potential of fibers decreased with increase in the amount of grafting. Stern potential (φ_δ) and the position (t) of slipping plane in the electric double layer of the fiber surface were estimated. φ_δ of grafted fibers decreased with increase in the amount of grafting and the value of t for grafted fibers was greater than that for ungrafted fiber.
It was suggested from these facts that the grafted nylon 6 fiber swelled remarkably in solution and that the hydrogel layer was formed at the surface by grafting of the fiber surface.

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The immobilization of enzyme using chitosan-aldehyde gels as novel supports, which were prepared by the reaction of chitosan with an aldehyde in 10% acetic acid and methanol, was investigated. In order to prepare the immobilized enzyme with high enzyme activity, the immobilization of enzyme using chitosan-aldehyde gels from various aldehydes was tried. The most active preparation was obtained on the enzyme immobilized in chitosan-formaldehyde gel. The immobilized, β-galactosidase using chitosan-formaldehyde gel was prepared with a high activity yield of 67% by incubating a mixture of 90 units of enzyme and 10g of hydrate gel with 1% glutaraldehyde at pH 5 and room temperature for 1hr. The enzyme immobilized by using chitosan-formaldehyde gel exhibited the optimum pH at 5, the optimum temperature at 50°C, and slightly improved thermal stability up to 60°C. The activity of chitosan-formaldehyde gel-immobilized enzyme packed in the column was retained without a remarkable drop in activity after being used over 20 days.

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The kinetic studies have been made of the binding of non-ionic azo dyes by β-naphthalenesulfonic acid-formaldehyde condensates (βNSF) by means of the stopped-flow and the temperaturejump methods.
The rate of binding is sensitive to the degree of condensation, N, of βNSF and to the behavior of βNSF as a flexible chain polyions. For βNSF with N>6, the time course of the binding measured by the stopped-flow method can be described by assuming that the binding occurs in two stages; a fast initial stage and a subsequent slow one. The fast stage is completed within 1ms (the dead time of the apparatus used). Whereas, for βNSF with N<5, the whole binding process finishes within the fast stage. The slow stage obeys pseudo first-order kinetics with k_app=0.16-0.23_s^-1, the experimental k_app's seem to be independent of the reactants concentration.
Then the fast stage was studied by means of the temperature-jump method. The relaxation curves for the binding by βNSF with N>5 can also be described by assuming two relaxation processes, a very fast initial relaxation (τ₁=ca. 15-25μs) and the subsequent slower one (τ₂=ca. 60-70μs). For βNSF with N<5, only the very fast process occurs. For the binding by βNSF with N=40(N>9), the values of τ₁ and τ₂ are independent of the reactant concentration, pH and pKa of the dye used.
Results obtained in this study suggest that the conformational change of βNSF to accommodate for the dye binding may participate in the rate determining step of the binding.

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Effects of the concentrations of sodium and hydrogen ions on the binding equilibria of 4-aminoazobenzene derivatives (model azo disperse dyes) by sodium salts of β-naphthalenesulfonic acid-formaldehyde condensates (βNSF) in water were determined spectrophotometrically; a βNSF with degree of condensation, N=40, was used. The detailed analysis of the results indicates that the binding of dye by the βNSF of a compact conformation is successfully described by an ion-exchange mechanism. At first, a trace amount of hydrogen ion in the solution is attached to the β-azo nitrogen of the dyes, then the protonated dye (DH) competes with sodium (Na) and hydrogen (H) ions for the dyeing sites in the βNSF, -SO₃^- The values of ion-exchange constants determined in the pH ranges of 4.126-4.9505 and 5.010-5.508 at 25°C were K^H_DH=0.14-0.60 and K^Na_DH-3.8-9.2×10^-4, respectively. The values of K^H_DH, obtained indicate the fact that the sulfonic acid group in the βNSF of a compact conformation behaves as a weak acid.

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The diffusion and the simultaneous reaction with cellulose of six reactive dyes bearing H-acid coupled with a substituted aniline as the chromophore and also bearing different reactive groups, dichlorotriazinyl, monochlorotriazinyl, dichloroquinoxaline-carbonyl and trichloropyrimidinyl, were investigated by the cylindrical film roll method. The experimental profiles of the active and the fixed species for these dyes agreed with the theoretical profiles described by the diffusion equation accompanied by the simultaneous pseudofirst-order reactions of the dye with cellulose and water, whose rate constants were denoted by K_c, and K_w, respectively. Linear relationships between log K_c, and pH were found for C. I. Reactive Red 41. The characteristic relationships similar to those observed by Ingamells et al. were found for Red 1 and Red 2, while they were not found for Red 3, Red 12 and Red 17 which had been applied at higher temperatures. The values of the surface dye concentration for Red 1, Red 2 and Red 41 decreased with increase in pH. The activation energies of the reaction with cellulose and those of the diffusion were found to vary with the reactive groups and, in the case of monochlorotriazinyl dyes, with the substituents on the triazine ring as well.

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Tri-O-benzylcellulose was oxidized to benzoylcellulose in good yields by ozonization. Degrees of substitution (DS) of benzoylcellulose thus prepared were higher than 2.5. A little depolymerization during the ozonization of tri-O-benzylcellulose was detected by gel permeation chromatography. In contrast, tri-O-p-methoxybenzylcellulose gave other reaction products than p-methoxybenzoylcellulose.

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