Studies on pitch and sticky problems during a last decade have been reviewed to search for possible overcoming policies in neutral papermaking process. It seems that one of the most effective means at present status is the use of cationic polymers with or without small quantities of alum, both of which are expected to scavenge the anionic trashes in system and to carry away the resinous materials with paper product. Various cautions are necessary, however, when applying them to the system containing mechanical pulp and/or calcium carbonate.

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This review relates to the new additives, which can solve the problems accompanied with gate roll coater operation.
A special type of modified polyamine can improve ink setting properties. And a certain type of polymer containing styrene can eliminate or alleviate plate fouling in offset printing and roll pattern in ultra light pigment coating.

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The Color Science Association of Japan has introduced the result of examination performed in co-operation with related organization in Japan, as to possibility whether the formula presented at CIE conference in Kyoto is adoptable to JIS as expressing method of whiteness.
The result shows that CIE whiteness formula advised by CIE, has approximate coincidence with psychological whiteness under a certain adoption limit.
However, if the limit of adoption range W<5Y-280 would be changed to smaller one such W<5Y-300, the relation between the whiteness and psycological scale would be improved.
Further discussion would be required as to this adoptable limit range.

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In the previous paper, the effects of wood extractives on resin speck formation in pulps, and resin deposition appeared as screen rejects were compared for bleached sulphate pulps from 24 Dipterocarpaceae woods grown in Sarawak. Taking consideration to the average diameter of vertical resin canals and the manner in which the canals were filled with resins and their distribution in the wood, the appearance frequency of resin was classified into four grades (_??_, _??_, +, ±) in the order of speck area.
Unfortunately, diameters of 24 wood discs used in the experiment were diversely distributed in the range from 20 to 85 cm. In the present report, therefore, speck area from 24 species were arranged in the descending order of disc diameter as shown in Fig. 1 (B). In the five species with appearance frequency _??_, four species were found to have the wood disk diameters larger than 40 cm. Conversely five species of seven species with±had those less than 30 cm. Namely, the larger the disc diameter seemed to be higher grade of appearance frequency of resin, and vise versa as shown in Fig. 1. This indicates that the relationships significant are found between wood disc diameter and resin speck formation.
Therefore, comparative studies on both speck formation and resin deposition as screen rejects were made by the use of S. kunstleri wood discs these diamter were 85 cm (L) and 50 cm (M) as shown in Fig. 2 and 3. The results are shown in Table 1, 2, and 3. Highly concentrated distribution of resin canals having larger diameter was found in the disc L compared to those in the three M discs (Top, Mid., Bot.). Among the latter three from a straight wood stem M of about 10 m high of S. kunstleri, the higher the location of the disc, the more number of series of resin canals with larger diameters were found. Surprisingly, no apparent series of vertical resin canals was found in both woods L and M within a range of disc diameter from zero to about 40 cm as shown in Fig. 6.This type of variation in canal distribution may happen to occur in other species of Dipterocarpaceae woods to cause significant effect on the appearance frequency of resin.
As shown in Table 2 and 3, the amounts of peculiar resins deposited as screen rejects in case of S. kunstleri were found to appear in the order of volume ratio of the canals having larger diameters to the chip volume. Total area of resin specks in pulp, however, appeared in the order of volume ratio of the canals to the chip.
Based on the mentioned above, trials were made to find out characteristic nature of the respective canals having the appearance frequency of resin _??_ of two Shorea species (No.11 and 8) and two Anisoptera species (No.23 and 24), and _??_ of five Shorea species (No.18, 9, 16, 14, and 10) as shown in Fig. 7. Among them, two Anisoptera species contain numerous diffuse vertical resin canals besides the normal ones. Each sample of 9 species, having canal volume ratio of about 0.2, 0.4, 0.6, and 0.8% to the chip were prepared by the same method as shown in Fig. 2-3, and then cooked and bleached to see the tatol speck area. The results were shown in Fig. 8-a. The each speck area was divided by the corresponding canal ratio to find out “the deposition index of resin speck” as shown by the dotted line in Fig.8-b. Because of dispersion of these data, “the average deposition index of resin speck” was calculated and finally shown by the solid line to be 532 for S. kunstleri, 80-111 for other three species with appearance frequency of resin _??_, and 8-34 for five species with_??_.

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