The paper gives an overview of research policies and some research activities in pulp and papermaking in Finland.
Some facts are about the special features of pulp and papermaking in Finland are summarised. These facts could be considered the essential driving forces of the research activities. In addition to running their own research laboratories, the Finnish pulp and paper industries generally participate actively in the planning and financing of research at institutes and at university departments.
The “research network” of Finnish pulp and papermaking (industry/institutes/universities), which is a very important strength factor is described. An overview is given of main current or recently concluded government-sponsored research programs. Common denominators of these programs are environmental issues, energy savings and highly refined paper products. Some specific examples are given of results from pulping, papermaking and forest products chemistry. In the future, changes in price relationships between raw materials, energy, labour force and capital will probably lead to emphasis of research on total life cycle analysis of the utilization of wood as a raw material and a better understanding of the relationship between pulping, washing and bleaching procedures and paper properties

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Development of some organosolv pulping systems including phenol, solvolysis and organic acid processes have been reviewed. The Alcell process and the Organocell process are also dealt with. Special emphasis is placed on the production mechanism of eugenol and isoeugenol from lignin during alcohol-bisulfite delignification.

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Since 1989 environmental pressure and the landfill problem have encouraged business machine and paper industries to utilize recycled paper for office use, and to recycle office wastepaper.
Several recycled paper products for xerographic copying machines and printers had been marketed previously, but early recycled papers caused problems such as paper jams and generation copy background with the equipment.
Research and development for correcting problems of recycled paper with xerographic equipment in response to the environmental demands are reviewed.
The recent technologies of cut sheet xerographic paper and wastepaper recycling have been combined and significantly improved to develop recycled papers of better quality for use in the office place.

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Ink transfer on paper is the most basical problem in printing because ink transfer effects printing quality directly. Although the effects of properties of ink and paper on ink transfer have been studied, ink set and trapping in the first step of printing are not clarified yet.
In this paper, the effects of ink characteristics and paper structure on ink set and trapping just after printing are discussed on the basis of experiments using various kind of inks and papers.

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The standard fiber analysis method such as TAPPI T 401 requires the analyst be skillful and experienced in the field of pulp and paper microscopy. No matter how skillful the analyst is, the measurement is still lacking in an objectivity. A new method for determining fiber composition of a pulp has been devised. This method is partly based on the standards but uses an image analysis and fiber length distribution data so that more accurate and objective results can be obtained.
To determine the weight ratio of fiber composition in a blend of different pulps, the fiber length distribution of a pulp was assumed to be a result of the superimposition of distributions of known pulps.
Since the weight ratio based only on fiber length data is not satisfactory, we have combined fiber length data with image analysis results to obtain the required accuracy.
The proposed method has provided a better result than the standard microscopic method by expert fiber analysts within a certain range of pulps, but further studies are required to device a more sophisticated method.

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Stress analysis under the surface compression for SCP medium (semi-chemical medium) in fiberboards which are shown as semi-elliptic and sinusoidal waves is considered. Then relations between stress distributions and shapes of SCP medium are discussed, and strength efficiencies (strength per mass of the corrugated sheet) E_fe and E_fs for elliptic and sinusoidal waves are discussed from results of the analysis. Obtained results are as follows :
(1) Lateral weight W_oe in SCP medium of the elliptic wave under the constant surface compression is smaller than lateral weight W_oe in the sinusoidal wave. Ratio of W_oe/W_oe is about 0.7. W_oe and W_oe decrease with the increment of thickness T of SCP medium.
(2) Maximum values (σ_emax for elliptic wave, σ_emax for sinusoidal wave) of their absolute stresses are on inner surfaces of contact positions with kraft liner. Ratio of/σ_emax/σ_emax is about 1.6 and increases with the increment of wave length L. Maximal values of absolute stresses for elliptic and sinusoidal waves of SCP medium occur at 7 L/32 and L/6 from their contact positions along the machine direction.
(3) In range ρ (radius of curvature at the top of SCP medium) >T/2 (T : thickness of the medium), σ_emax decreases with the increment of T. Initially σ_emax decreases, then increases with increments of L and wave height h. In the range ρ> T/2, E_fe and E_fs increase and decrease with increases of T, L and h.

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Concerning pulp production from non-woody plants, we have been studying on the chemical pulping of rice and wheat straws since 1987. There are two reasons why this research project was planned. (a) More than 99% of pulp are produced from wood in Japan. Considering the increase of paper demands in future, it is doubtful whether or not we are able to obtain enough materials in future, and we may be obliged to use non-woody plants even in a small amount. For information, kenaf, non-woody plant is noticed recently as pulp materials. (b) China is well-known country to use non-woody plants like straw, reed, bamboo and so on as pulp materials. Soda cooking has been mainly adopted in the case of pulp making. However, the recovery of soda and the utilization of dissolved lignin in black liquor are not developed yet. This is due to a large quantity of ash which disturbs the post-treatment of black liquor. On the basis of two reasons above-mentioned, it is necessary for Japan to adjust the pulping process of non-woody plants seems to be appropriate at the present technical level. Moreover, the removal of ash from black liquor and the utilization of lignin are also indispensable to be solved.
This report describes the pulp analysis and the pulp sheet strength of rice and wheat straws by soda and alkaline sulfite cookings. Moreover, soda lignin was isolated from black liquor and sulfomethylated, and the dispersion property of sulfomethylated lignin was examined. The results are summarized as follows :
(1) Delignification of rice straw by soda cooking is more rapid than that of wheat straw. Corresponding with delignification, the brightness of the former is higher than that of the latter.
(2) The ash fraction is dissolved during soda cooking, although a few % of ash is still contained in soda pulp. However, the ash fraction during alkaline sulfite pulping is difficult to be dissolved, and 1617% of ash are contained in pulp. Such a high amount of ash may regulate the extensive application of alkaline sulfite pulp.
(3) Sheet strength of soda pulp is higher than that of alkaline sulfite pulp. However, these strength results represent only the preliminary work, because there is the difference of about 100 ml CSF between soda and alkaline sulfite pulps.
(4) Standard dispersing number of sulfomethylated lignin is higher in rice straw than in wheat straw.
(5) Summarizing the previous (2) - (3) items, soda pulp is superior than alkaline sulfite pulp.

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