In connection with work on southern tropical wood resins we investigated deresination pattern of chip resins during kraft pulping processes and some of these results have been described. This paper reports further work in this field. In order to minimize the possible errors inevitably coming from the process of experiments, the washing condition was kept constant and the operation was followed by measuring the remaining pulp resins.
Although the washing effect on deresination of the tropical wood pulps may be comparatively less, the fundamentals are similar to that of the Japanese wood kraft pulps.
The effects of the different washing variables on the deresination rate were tested to be systematized, mainly because the nature of pitch deposition on the subsequent stage is unknown.
The seasonal variation of pitch deposition can be considered to be caused most probably by temperature deviation of the pulp mill water, unrelated to other operating conditions. It is apparent that an optimum liquor temperature must exist for any maximum pitch deposition, but since this will vary somewhat from resin to resin, depending on the type of resin components, it is impossible to define any rigid set of temperatures that should be avoided.
The results of tackiness determination of resin as well as the nature of pitch deposition are also given.

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A new interest in registering behaviors of coated papers has arisen from recent trend towards eliminating paper conditioning at printing plants. Presented in this report are some of the new findings obtained from our recent studies regarding the registering behaviors of various coated papers which have been made in a most realistic way by double-printing a specially designed test pattern with a commercial single-color offset press and measuring the resultant misregister between1st- and 2nd-laid images by means of GATF Register Rule.
Dependence of register upon ΔRH, the difference in relative humidity between paper and atmosphere, was found to vary at every location, and in each direction, on the printed sheets. The misregister in MD-G (machine direction, gripper edge) is usually not important, but those in MD-B (machine direction, back edge) and CMD (cross machine direction) are often problematic and do not always move parallel to ecah other as ΔRH changes. The time of exposing the unwrapped paper stack to the atmosphere before being printed is another important factor affecting the dependence of register upon ΔRH. It has been indicated that appropriate control of relative humidity of coated paper to minimize the most troublesome misregister in MD-B depends upon every expanding and contractig factors as well as handling of paper involved in printing. When the time of exposure before printing is short, the relative humidity of paper is recommended to be controlled slightly lower than that of printing atomosphere. When it is long, the relative humidity of paper must be equal to or slightly higher than that of atomosphere so that the occurrence of troublesome wavy edges may be prevented.

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