Since 1994, small-sized lithium-ion batteries have been used in our daily life, such as cellular phone, digital camera, digital audio, note-book computer, power-assisted bicycle and various power tools. In 2009, electric vehicles (EV) using large-sized lithium-ion batteries (10-25 kWh) have been commercialized and now the production numbers are rapidly increasing as the most promising device under the collaboration of automobile companies and battery makers. During last decay, the battery performances such as energy density, power density, and service life have been improved significantly. Also, much efforts for solving safety problem have been put into the development of battery materials such as positive electrodes, negative ones, separators and electrolytes. However, the performances and safety level of the large-sized batteries are not enough for use in the practical EVs. Further improvement has been required for high-speed charging-discharging performances even at a low temperature. The development of advanced separators using high performance papers would be one of the most important task for satisfying both high performances and safety for the large-sized lithium-ion batteries.

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The plant cell wall consists of cellulose nanofibers or cellulose microfibril bundles. Since nanofibers are tight bundles of semi-crystalline extended cellulose chains, their thermal expansion is as low as that of quartz, while their strength is five times that of steel. However, the industrial utilization of nanofibers has been limited despite their being the most abundant biomass resource on the earth. Recently, due to the risk of depletion of oil reserves and global environmental concerns, the effective extraction of cellulose nanofibers and their utilizations have gained increasing attention. This review summarizes the research works on the production of nanofibers from plant resources and their application to design polymer composites.

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A novel metal-capturing fiber was successfully developed by wet-spinning of viscose rayon with a chelating polymer having a long-chain aminocarboxylate backbone and grafted chelating resins. Such procedure was very simple and as-designed fiber composite demonstrated a high affinity for various metal ions. Besides, neither alkali nor alkaline earth elements were adsorbed under the acidic conditions. The developed metal-capturing fiber would be effective to remove and recover the targeted trace metals from sample solutions in high salt concentrations such as environmental and food samples. This report summarizes the functional design of the chelating resin and the development of the metal-capturing fiber.

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Biodegradable materials are widely applied to various products from the environmental viewpoints due to their gradual degradation to water and CO₂ by soil microorganisms. However,there still remain some problems in the practical manufacturing of biodegradable fibers, e.g., the agglutination in the melt-spinning process and high frictional properties. Such undesirable features cause poor openability and/or dispersibility in the web-forming to produce nonwoven fabrics. In this paper,we propose one solution by controlling the crystallinity of PLA mixed with biodegradable resin and by using fiber finish with more slippery properties. As-designed biodegradable fibers possess the processing suitability to make the fabrics,and are equivalent to polyolefin fibers in physical properties,while keeping faster biodegradability. Therefore,a potential market is being developed to make use of these unique characteristics.

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Newly-developed short cut fìbers for wet-laid nonwovens are introduced in this report. At fìrst, Bio-PET short cut fìbers composed of biomass EG (ethylene glycol) are proposed as an eco-friendly material for environmental strategies. The Bio-PET fibers can contribute much to the reduction of both fossil resources consumption and CO₂ emission. Besides, new papers made of only “Nano-Front™" short cut fìbers and fìne fìbers with unique profìled cross sections (less than 1 dtex) have been developed and the expected novel functions are presented.

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Japan, after World War II, has put full-scale efforts into the re-establishment of the industrial fields of steel, ship building, motorcar, electronics, precision machines, civil engineering, construction and petrochemistry. The general consensus of all Japanese people,"Catch up with and overtake western nations", has strongly pushed forward the progress of various industries including the related supporting ones. However, it was proved that manufacturing itself is the primary factor of environmental destruction, and the Club of Rome reported "The Limits to Growth" in 1970; after that it took more than 30 years before the world started for the same objective, aiming at a sustainable society. Japan's economic strength equivalent to Europe and the United States is at a standstill now, struggling to create the industrial structure innovation. Japan's specialty such as ship building and textile industry has already been shifted to overseas in the early stage of economic growth, and besides another strong area, motor industry, is now facing difficulties. As developing countries are gaining more power, innovative creation of future-generation industry is anticipated as a substitute for the motor industry. In such industrial situations, we need to take into full consideration the future of the high perforrmance paper from various angles, which should be from growing industry, business field, environmental issues, customer needs and new technology. Also above all, the high perforrmance paper rosy future needs to be realizedthrough horizontal cooperation by all person engaged in the same industry.

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Innovative technology for needleless electrospinning,"Electro bubble spinning",was successfully developed. The novel spinning method enables the production of nanofibers by stirring the spinning liquid with compressed air,resulting in the improvement of the productivity as compared to the conventional needle processes. The pore size of wet-laid nonwoven fabrics was reduced by spraying nanofibers,and the pore size distribution became narrower. Besides,this technique could control the particle sedimentation in the inorganic particle dispersive system by stirring the spinning liquid with compressed air. Thus,the continuous fabrication of organic-inorganic hybrid nanofibers and composite nanofibers was also achieved. In addition,ceramic nanofibers were prepared by the calcinations of particle dispersive nanofibers. The hydrolyzed tetraethoxy orthosilicate sol can regulate the fiber diameters in the mass production system,and the multilayer nanofibers with different diameters are also manufactured by the electro bubble spinning of these sol precursors. The electro bubble spinning system without needles is expected to improve the productivity of nanofibers,and to provide a possibility to cut down the production cost.

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Fibrous polymer materials with a pulp-like shape are useful as a raw constituent for high performance paper. In this report, we introduce a new method for processing synthetic polymers in a pulp form using a shear force of steam and subsequent coagulation in a poor solvent, where the polymer solution immediately changes into the pulp form. This synthetic pulp can be fabricated into a sheet by wet papermaking and/or dry molding methods. As-designed sheets possess original properties of polymers, and can be utilized in a wide range of applications such as air filters, battery materials and artificiall leathers.

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Various acrylate materials have been developed for emergent functionalization such as antibacterial, deodorant, flame-resistant, water-absorbing, hygroscopic and heating properties. Furthermore, the movement to aim at health and comfortable life arises from the current increase of medical expenses and forthcoming aging society. Thus, there is a sharp increase in the demand for health care and amenity materials. This paper reports the recent development of multifunctional acrylate materials for health care to meet such demand.

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Paper materials coated with unused components in citrus essential oil have an insect-repellent property against Sitophilus zeamais. This paper reports the applications of the functional papers to cardboard box and cereal bag for repelling grain-storage insects.

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