Nowadays, SBR latexes are used as a main binder for color developer and also for micro capsule. (CB and CF paper) They give various effect on the properties of carbonless paper. In this paper, technical trend in this field is reviewed. And, the effects of colloidal and polymer design of SBR latex on the following important performance items of carbonless paper;
1) Picking Strength
2) Density of the developed color
3) Light resistance of the developed color
4) Setting speed of desensitizing ink
5) Smudging are discussed.

View full abstract

Sumitomo Heavy Industries, Ltd., has developed a new type of airpreheater “SUMITOMO-OCAP” and a new type of hot water recovery system “SUMITOMO-VALMEX”.
“SUMITOMO-OCAP” was commercialized by introducing technical Patents from NorthAtlantic Technologies, Inc., U. S. A., and is a very unique gas-to-gas and gas-to-liquid heat exchanger for a variety of heat recovery application. There are many advantages to OCAP's innovative no-weld construction.
“SUMITOMO-VALMEX” was commercialized by introducing technical know-how from Valmet Paper Machinery Inc. of Finland, and is a new type of hot water recovery system featuring the advantages characteristic of both the plate type and tube type heat exchangers.
Large umber of OCAP & VALMEX have been delivered to many paper & pulp companies and have been applied for their heat recovery systems.

View full abstract

The sulfite-quinone cooking has been investigated as an alternative to the kraft process in terms of delignification, pulp yields, and pulp qualities. However, behaviors of lignin in this cooking have not been clarified, and there are few studies in which delignification selectivity and pulp qualities were compared at given delignification rates and H-factors with those of the soda-quinone and the kraft-quinone cookings. In this study, yezo spruce/saghalien fir mixed chips and beech chips were cooked by the three kinds of cookings under the conditions where the delignification at a given H-factor (cooking temp. : 170°C cooking time : 2 h) were equal. Pulp yields, handsheet strength properties, and characteristics of lignins in those pulps and black liquors were compared, and behaviors of lignin and mechanism of delignification in the sulfite-quinone pulping were discussed. In these experiments, 1, 4-dihydro-9, 10-dihydroxyanthracene sodium salt (DDA) was used as a quinone additive, and this sulfite-quinone cooking was called the alkaline sulfite-DDA cooking because sodium hydroxide, sodium sulfite, and DDA were used as cooking chemicals. The results are summarized as follows :
(1) The alkaline sulfite-DDA cooking of yezo spruce/saghalien fir wood gave pulp of almost the same kappa no. 50 as the soda-DDA and the krart-DDA cookings. At kappa no. 50, the total pulp yields of the former were higher than those of the latter. However, the screened pulp yields of the alkaline sufite-DDA cooking were almost the same as those of the kraft-DDA cooking and slightly lower than those of the soda-DDA cooking because of its higher yields of screen rejects.
(2) This cooking of beech wood gave pulp of kappa no. 26.4, but it had no advantage of pulp yields compared with the soda-DDA and the kraft-DDA cookings.
(3) The contents of sulfonic acid group of lignin in pulps given by this cooking were about 0.1-0.2/phenyl propane unit.
(4) Handsheet strength properties of this cooking were almost the same as those of the kraft-DDA cooking.
(5) Gel chromatography indicated that the dissolved lignin of this cooking was richer in low-molucular lignin fractions than those of the other cookings.
(6) Alkaline nitrobenzene oxidation of screened pulps and black liquors of this cooking gave higher yields of vanillin (soft wood) or vanillin and syringaldehyde (hard wood) than those of the others.
(7) In the alkaline sulfite-DDA cooking, the condensation of lignin was depressed by the addition of sodium sulfite. This must be a reason why delignification is accelerated together with the increase of solubilyty of lignin with the cleavage of β-ether linkages by quinone compounds and the sulfonation by sulfite.

View full abstract

Liquid transfer and dynamic penetration as well as their relationships to roughness of papers, such as softwood and hardwood bleached sulphate pulp sheets and commercial india and coated papers, were investigated.
As smoothness of paper surface increased, the initial liquid transfer and absorption volume decreased. The amount of water transfered at the contact time 0, which could be obtained by extrapolation from the relationship between liquid transfer and contact time, might be interpreted as the roughness index Kr'. This became smaller when the void volume on the paper surface decreased. Moreover, the thickness of water layer and its volume ratio to that of void on the paper surface at the initial stage were calculated as 11.1 μm and 46% for the softwood bleached sulphate sheet, 9.6μm and 54% for the hardwood sheet, 8.8 μm and 41% for the india paper and 1.8μm and 16% for the coated paper, respectively.

View full abstract