In the second part of this series, wetting of fiber pad (fiber mat) and paper were reviewed. With these substances consisting of network structure, absorption and penetration are indispensable, so that the description is made of them within a scope concerning the wetting. The liquid migration from coating color into paper is also included.

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The purpose of this study was to obtain information that would help to improve the quality of paper produced by papermaking machines. Irregularities in fiber concentration in the flow of pulp suspension, and turbulence intensity, were measured in a duct, at the inlet of which various types of turbulence generators were installed. The turbulence intensity of the suspension flow was measured by two small pressure transducers. Irregularities in concentration were measured by fluctuations in the intensity of light transmitted through the pulp suspension in the duct section. The results show that irregularities in concentration are inversly related to turbulence intensity. It was also found that there is a time delay in the changes of concentration due to turbulence variations. It is believed that the results of this study will provide useful information for the development of improved papermaking machine headboxes.

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In this commentary, energy analysis was applied on KP process from the veiw point of exergy concept. The energy balance indicated the exergy loss in recovery boiler to be 8056 of the total loss in KP process.
Though the exergy efficiency of KP process is inferior to the other chemical processes, it is difficult to improve the efficiency under the existing pulping process. Utilization of the lignin and other organics burned in recovery boiler is one of the ways to improve the efficiency drastically. The other way is conversion of delignification reagent to, such as, organic solvent which require lower energy for its reuse as lignin extractor than alkali recovery. From this point, organosolv pulping can be a solution to the better energy usage.

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Young's modulus from a conventional elongation test of paper is usually underestimated, mainly because slippage occurs between the specimen and the grips during loading. A more accurate Young's modulus is sometimes required for a precise discussion of paper science or the suitable material design of paper. Although the vibrating reed method and the ultrasonic method have both been proposed for determining Young's modulus of paper, these techniques are limited by the requirement of special devices and a complicated measurement procedure. Therefore, a modified calculation method for Young's modulus from the elongation test is discussed in this study.
The apparent deformation (Δd) of paper in a conventional elongation test can be divided into two parts, a real sheet deformation (Δf) and a false deformation which includes the slippage (Δs). The percentage of Δs of the apparent strain becomes larger as span 1 decreases, because for a certain kind of paper at a certain external loading level Δs is considered to be the same regardless of test span. The amount of Δs at a given load can be obtained by extrapolating the relationship between apparent deformation at the load level and test span to zero span. Thus, Young's modulus can be calculated after the correction of sheet strain by the value of Δs.
The effect of restraint of lateral contraction near the grips on extensional rigidity was found to be small when calculated by the finite element method, provided that the span is more than twice the sample width. The results suggest that the specimen span should be more than 30 mm.
Young's modulus corrected in this way was fairly close to that obtained from the vibrating reed method.

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Characteristics of thermal decomposition of cigarette paper from flax pulp blended with wood pulp (blend ratio 9 : 1) treated with various burning chemicals (organic acid salts and phosphates) were investigated by thermogravimetry and differential scanning calorimetry (TG-DSC) both in air and helium atmosphere respectively.
The initial and the most active temperature at pyrolysis of blended pulp cigarette paper treated with burning chemicals were lower than those of the untreated cigarette paper both in air and helium. The amount of residual char of the treated cigarette paper was higher. A distinct effect on pyrolysis of the treated cigarette paper was observed at about 1% adsorption of burning chemicals.
Sodium and potassium salts of burning chemicals exert the different characteristic effect on smoking flavor and taste of treated cigarette paper.

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Using the extended computer model in Part III, the effects of the variations of dryer operating conditions in cross directions are investigated with two commercially running machines, a low speed fine paper machine and a high speed LWC machine. The cross directional data are converted to percent deviations from averages of each cylinders respectively, to get more useful informations on cross directional variations.
Regarding operating conditions, followings are summarized.
1. Cylinder pocket air absolute humidities show far bigger percent deviations than cylinder surface temperatures and cylinder pocket air temperatures in both machines.
2. The fine paper machine has bigger variations than the LWC machine in above three operating conditions.
The simulated results suggest several fundamental differences between two kinds of paper machines as followings.
1. In the fine paper machine, the cross directional variations of cylinder surface temperatures primarily cause the cross directional variations of water evaporation at each cylinder, which are accumulated to produce the variations of web moisture contents.
2. Even though a web dries up in a rather good moisture profile, it is suggested that its moisture profile during drying is not necessarily even all the way. The web moisture difference of 0.05 g water/g. fibre in a cross direction may well be expected at some cylinder.
3. In the LWC machine, the cross directional variation of water evaporation is rather influenced by that of cylinder pocket air absolute humidity, not by that of cylinder surface temperature.
4. One of the reasons of the above different behaviors may be that the ratio of water evaporation in pockets to total evaporation is higher in the LWC machine, which means that the pocket conditions are more influential in a high speed machine than in a low speed machine.
5. Moreover, the cylinder surface temperature variations of the LWC machine are quite limited. With this fact combined with the above reason, they become less important than the pocket conditions.

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