With a view to analyze the present status and foresee the future perspectives of paper technology, a roundtable discussion was taken place among specialists from paper industry, machine manufacturer and university. Pulp and paper equipment manufacturers of Scandinavian countries were also invited to join this meeting.
The topics covered from the resource problems to the forefront of pulp and paper technology as well as paper products, and the discussion was conducted according to the following sequence.
1. Introduction
2. Resource problems 3. Biotechnology and biomass utilizations
4. Waste paper and solid waste problems
5. Utilization of nonwoody pulp
6. Pulping technology
7. Bleaching technology
8. Energy and manpower saving
9. New pulping technology
10. Sheet forming technology
11. Coating technology
12. Information and communication papers
13. Packaging papers
14. High performance and specialty papers
15. How to make paper industry more attractive to future generations
16. Paper science and technology education
17. Dreams for future technology
First the historical development of paper industry in Japan was traced back, and the present status and key issues of paper technology as well as inherent issues of paper industry were pointed out by the chairman of this discussion meeting. Then the discussion started.
As for resource roblems, the conditions of sustainable supply of pulp wood in Japan for the next generation was discussed associated with the utlization of domestic forest resources, global environmental issues and biotechnology applications.
The forefront of high-technology like biotec, electronics and advanced materials will have keen impact on the future development in paper technology.
A veriety of key technology to cope with global environmental issues in paper industry like chloline-free bleaching, bio-pulping, bio-bleaching were discussed.
Technological possibilities for the development of innovative pulping and bleaching methods, highest paper machine speed, waste paper utilization ratio etc. were also dealt with in the meeting. Significance of education and construction of image of paper industry to maintain sustainable progress and development of paper industry in the next era was pointed out.
Lastly each participant had expressed his personal dream for the future paper technology.
This voluminous discussion is expected to provide the reader with wider and global perspectives for the paper technology in the next global and borderless technology era.

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Recently pulp and paper plants became more sophisticated, and the role of instrumentation techniques became essential for their operation. This paper reviews the history of the development of instrumentation techniques in pulp and paper processes. The paper stresses the importance of maintenance techniques in a total production system in future. The paper also discusses emerging techniques such as neural network and process simulation to reduce the operators work load.

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Meanwhile, dioxin draws the largest attention among effluent components from pulp and paper factories. Long ago, we installed oxygen bleaching equipment as the most effective means of reducing dioxin challenges in the pulp and paper industries of countries in the Pan-Pacific region attending this Conference.

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Mitsubishi New Twin-Wire Former has been developed from extensive fundamental research and innovative technology timely consolidating the industry's trend and customer's needs. The New Former's unique drainage concept provides the possibility of producing many kinds of printing paper grades with superior sheet structure over a wide range of basis weight and speeds.

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A theoretical study was made on the influence of headbox elements on paper quality with reference to actually measured data, for the purposes of improving headboxes' performance and preventing troubles in papermaking.
It was derived from the study that the non-uniformity in the stock jet may cause uneven basis weight profiles, fiber orientation etc. For further quantitative analysis of the possible causes, an imaginary headbox was set and computer simulated calculations were conducted with regards to local flow conditions in the upstream aiming at finding their influence on the jet.

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Application of enzyme to the kraft pulp bleaching was investigated to reduce the amount of AOX generated during bleaching.
The pulp which had been pretreated with xylanase was bleached using several sequences and the qualities of the resultant pulps were compared with one another.
As a result, it was found that the pretreatment with xylanase enabled to reduce the amount of chlorine or chlorine dioxide at the first stage by 20 to 25% without any adverse influence on the pulp quality.
The reason why the brightness was improved owing to the treatment with xylanase is considered to result not only the reduction of the kappa number of (D/C) E pulp, but also the improvement in the bleachability in a subsequent stage.
Reference is also made to a non-chlorine bleaching trial on the mill scale using the xylanase.

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The present state and the future one of the deinking market and technology in Pan Pacific countries are described in this paper.
The production of deinked pulp (DIP) will be rapidly increased in near future in Pan Pacific countries.
The deinking with a flotating process has been and will be superior.
The impact of DIP production increment is different in each country. It is mainly on the environment and resources problems in ripe countries and on the appropriation for the shortage of pulp sources with improving life in advancing countries.
The technological difference in flotation, soaking and dispersion are discussed in correlating with the deinking agent (DIA). The higher G/L (gas by liquid) flotaters have been installed in some Japanese mills. Thus displector type DIA with a good ink detachability, a low foaming and a quick foam disapperance have been developped. The soaking process is useful to produce the high quality DIP, because it is benfitable for deinking by chemical reactions with deinking chemicals. The disperser and/or the kneader are usually installed in many mills. This process is useful to peel the undetached inks from cellulose fiber for deinking ONP (old newsprint). Free inks are finer by this operation and become difficult to be removed on the flotater. The divided addition of DIA is useful to this trouble.
The dispersing process is used for adjusting the ink particles distribution in deinking waste toner printed paper. DIA with a strong affinity to toner inks has been developped.

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There are two trends in sizing technology in modern papermaking : the change from acid to neutral stock sizing and the increase in surface sizing. Alkyl ketene dimer, alkenyl succinic anhydride and cationic polymer dispersions are commonly used for the neutral stock sizing of woodfree paper grades.
In this paper, the specific properties of AKD, cationic polymeric sizing agents and combinations of both groups are reviewed. It is also demonstrated that the application of polymeric sizing agents in the size press is an interesting alternative to conventional wet end sizing. Neither the products nor the two processes, stock or size press addition, should be seen as simple alternatives to one another. Each should used as a basis for developing synergisms and working out the most efficient technical and economic solutions.

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One of the most important quality parameters concerning finished paper is curl. Of the many mechanisms which induce it, the three most prevalent are attributed to drying conditions, variations in fiber orientation, and single sided coatings. Current methods employed to address and correct for curl provide limited, and in some instances, complex solutions. Recent applications representing varying ranges of operating conditions demonstrate the controlled delivery of steam utilizing a Coanda Nozzle* as a superior decurling medium.
(*The paper industry has long utilized the Coanda Nozzle in air flotation dryers. The discovery of the Coanda effect is attributed to Henri-Marie Coanda whom some credit with the first jet aircraftin 1910)

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In the paper manufacturing industry, process computer has been adopted from early periods for the purpose of monitoring and controlling manufacturing processes. However, various kinds of intelligent equipment used for such production system are extremely sensitive to the industrial (corrosive) environments. This report will introduce the mechanism, various test data and examples of implementation of a corrosion control system based on the gas removal technology by chemical adsorbent as “protective measures against corrosion of process computer” in such industrial environments.

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