2007年4月 紙パ技協誌

Characteristics of Technical Development in the Japanese Paper Industry
-A Welcoming for Newcomers to the Industry-

Kiyoaki Iida
Project for preserving and publicizing technical archives of the Japanese paper industry

 Though it has been disadvantageous in wood resource and energy supply, the Japanese paper industry has been one of major paper producers in the world. That fact demonstrates that the Japanese paper industry has technical capability, comparable to other major players in the world.
 Technical capability is not easy to define, as it has many faces. So, it is divided in six categories, namely strategic planning, wood resource development, energy conservation, productivity and quality control, environment preservation and R & D power. The historical efforts of the industry in these six categories are reviewed.
 It turns out that the Japanese paper industry has been coping with successive changes and difficulties in the business with its technical capability. Its flexible and challenging attitude toward problems is deserved to be proud of. With that capability, the industry has been survived in the international competition.
 The industry will face difficulties in the future as it had in the past. It will be flexible and challenging as it did.

Remodelling Effects and Operating Experience of ISHINOMAKI PM N5

Hiroki Nagata
Ishinomaki Mill, Nippon Paper Industries Co., Ltd.

 Paper Machine N5 in Ishinomaki Mill started the operation on 1988 as on-line blade coating machine. This is one of the nucleus machines which produces approximately 500-ton of LWC per day.
 In 2005 September, in order to achieve following "Quality improvement", "Production increase" and "Reduction of labor",a large-scale remodelling was installed.
 (1) On top former conversion
 (2) 3P shoe press conversion
 (3) On-line hot soft nip calendar addition
 (4) Reel center wind conversion
 (5) Disuse of the rereeler and super calendar
 (6) Automated winder core supply system addition
and so on.
 This report is described about the remodelling summary and the latest operation experience of PM N5.

Operational Experience of Gas Engine
-Reduction of CO2 by Energy Plant Conversion-

Kazuyoshi Seo
Takasago Mill, Mitsubishi Paper Mills Limited

 Today, environment protection and energy-savings are crucial issue not only for industries but also for households and individuals.
 MPM carries an environment charter and slash of carbon-dioxide emission is regarded as one of the major subjects to be tackled. One example is the implementation of a power plant in Takasago mill operated by high-efficiency gas engine. The plant, with the help of ESCO, materialized co-generation and turning the fuel from petroleum to gas. We will accomplish the reduction of carbon-dioxide emission in Takasago mill by 27% in accordance with our plan.

Application of Photocatalytic Effect to Coated Papers

Hidehiko Kai
Pulp and Paper Laboratory, Nippon Paper Industries Co., Ltd.

 Titanium dioxide works as a photocatalyst oxidizing most of organic matter strongly under the light which has a wavelength around 400 nm or shorter than 400 nm. Organic matter is decomposed to CO2, H2O, and so on. In these days, there are many products with the functions of deodorization, sterilization, and self-cleaning in the market. Photocatalyst TiO2 has extremely small diameter around 10 to 20 nm. The reason of being nano order is large surface area. For instance, the average diameter of 150 nm TiO2 is estimated about 10 m2/g, while 7 nm TiO2 has a greater surface area of 320 m2. We found that titanium dioxide which has diameter around 10 nm works most effective when then are applied as a coating pigment. We have developed unique "photocatalyst paper" with air purifying effect. TiO2 surface modified with decomposable binder by TiO2 were used to avoid chalking. The photo catalytic paper includes new technologies such as preventing chalking and printability control.

Efforts for Green Procurement of Raw Materials

Yoshiaki Matsubayashi
Environmental Management Department, Oji Paper Co., Ltd.

 In 1994, Oji Paper introduced its own New Raw Material Safety Sheets to improve the chemical substance management. Under this cutting-edge green procurement system, new raw materials are evaluated whether they can be safely handled by employees in our mills and used in our products, and also reviewed to prevent environmental pollution.
 The Oji Paper Group requests suppliers to provide our Safety Sheets ahead of the trial of new raw materials, and when they include substances that do not meet the criteria established, the trial can be stopped.
 JIS Z 7250 requires manufacturers and importers that sell chemical substances to provide Material Safety Data Sheet (MSDS) to customers, which contains information on the safety and proper handling of chemical substances. The Oji Paper Group obtains MSDS prior to the trial of new raw materials. However, it is often the case that the information on MSDS from suppliers is inadequate for assessing the raw materials to ensure the safety during production and use, and for complying with the green procurement of our customers. Accordingly, the system of our unique New Raw Material Safety Sheets is becoming more important in these days and progressing to attain our green procurement.

Development of Water-Resistant Paper
-Compatible with Color Laser Printers『OPER MDP』-

Masaaki Fukunaga
Product Laboratory, Nippon Paper Industries Co., Ltd.

 A waterproof paper "OPER", which maintains the same characteristics as general papers like 'softness', 'printability', 'convertibility', is used in a commercial printing and converting fields. As recently in a commercial printing field, on-demand printing is growing remarkably, we developed "OPER MDP" for color laser printings. As a countermeasure against high temperature treatment in the laser beam printing, "OPER MDP" is composed of a sheet of paper with higher internal bond strength and heat-resisting resin layers are extrusion laminated on both side of the sheet. And on the heat-resisting layers, coating layers are given to improve the electric properties and the fixing with toner. In this paper, we would like to show the significant characteristics of the newly developed "OPER MDP" and how we develop the product.

Operating Experience of RPF Boiler at Oita Mill

Yoshinobu Koike
Oita Mill, Oji Paperboard Co., Ltd.

 Oji Paperboard Co., Ltd., Oita Mill, using favorable geographical conditions, has started its operation on November 1957. Since then as environmentally friendly products, the Mill has been producing corrugated paper and white board paper. Particularly considering the environment seriously, we have installed facilities and have been trying to preserve the local and global environment.
 The Mill has been operating a clean boiler, whose main fuel is RPF (Refuse Paper & Plastic Fuel). RPF consists of mixture of recovered paper that is hard to be used as material for recycled paper and also waste plastic, which contributes to reduce the waste globally. Furthermore, comparing to the fossil fuel, RPF generates less CO2, which leads to contributes to prevent the global warming.
 Here, the outline, character and operational records of the RPF (#2) boiler and its electric generator(steam condition;11.6Mpa×541℃,max200t/h) facilities are reported.

Latest Development in Forming Technology

Timo Valkama
Metso Paper Inc.
Takashi Akazawa
Metso-SHI Co., Ltd.

 The ability of a papermachine to provide value for its owners depends, to a large extend, on the technical concepts chosen. The main components of a machine are developed in phases over the years. As a consequence, the key sections of a papermachine may have different operating ranges. Each new section can be utilized only partially, if other sections do not fully support the operating range of the new section.
 The new ValShoe and BelShoe technology developed by Metso Paper will improve the productivity and profitability of hybrid formers and bring exiting BelBaie formers BelBaie's to competetive level with gaptechnology. The new technology is cost-effective and competitive with any other technical solution available today. Considering the existing limitation and unutilized capacity of current production lines, ValFormer and BelBaie V technologies open up new opportunities for increasing the lifetime of the entire production line.

Estimation of Yield Variation in KP Mill

Junji Tanaka
Research and Development Center, Kawasaki Kasei Chemicals Ltd.

 SAQ® has been used as a cooking additive in many kraft pulp (KP) mills. This process is known as "Quinone Cooking". In order to establish a convenient method for estimation of KP yield variation by SAQ addition in pulp mill, analysis of black liquor is investigated.
 The yield variations by SAQ addition were compared between analysis of black liquor and actual measurement of pulp weight using the laboratory test sample. This result that estimated the variation of pulp yield was in agreement with the calculated value by actual measurement of pulp.
 Mill scale trials were conducted to examine the effect of SAQ. Black liquor samples were used the extracted liquor from a digester. As a result, the increases of pulp yield were observed by analysis of black liquor in all trials.

The Influence of Wet End Chemicals on Paper Density and Strength
-The Effect of Paper Additives Used for "Bulky Paper"-

Masayuki Takishita, Yohei Otsuka and Daijiro Arai
Paper Chemicals Division, Arakawa Chemical Industries, Ltd.

 Low-density paper is now most trendy in Japanese market in recent years. Consumption of low-density paper, called "bulky paper", becomes higher and the market grows getting larger. Many types of "bulky paper" have been developed, and most of them are used for high quality printing paper, million-seller book, wood-free printing paper, and so on.
 One of the most important feature of "bulky paper" is a thickness of the paper. Although the basis weight of paper is same, bulky paper is thicker, lighter and softer than traditional ones. Paper strength of bulky paper is supposed to be weaker, therefore, it is important to prevent decreasing tensile strength or internal bond strength of the paper. In order to produce well-balanced sheet, addition level of paper strength agent, such as cationic starch, modified polyacrylamide, and bulking promoters (agent), organic and inorganic compounds, are discussed.

Introduction of Paper Technology Center for Stock Preparation
-Introduction of the Stock Preparation Trial Facility-

Takayuki Kokubun
Voith IHI Paper Technology Co., Ltd.

 In order to meet our customers' demands, Voith Paper and VIPT (Voith IHI Paper Technology) are ready to conduct stock preparation trials. Each single equipment trial as well as systematic trial can be conducted by customers' various requirements. Depending on what they would like to test, through reviewing the situation we can offer the most appropriate trial condition in advance and advise what trial facilities would be the most suitable one for them.
 Now, here we would like to introduce the stock preparation trial facilities of Voith Paper, Ravensburg and Heidenheim mills and VIPT's Paper Technology Center.

Structural Analysis of Water Resistance Paper Using New Types of Materials

Yoko Saito, Liu Xiang, Hideki Touda and Junji Kasai
ZEON CORPORATION, R&D Center Elastomer & C5 Chemicals

 We developed new materials that are called PVA-graft-Latexes. PVA-graft-Latexes are produced by grafting reaction of PVA as protective colloid on the surface of polymer particles. When we coat these PVA-graft-Latexes on the substrate materials such as papers, they show excellently high water resistance. We observed the latex films by using AFM. The structure of the coated film using PVA-graft-Latexes has not changed before and after contact with water. On the other hand, the coated film using conventional latexes has changed remarkably. The contact angle of the coated film using PVA-graft-Latexes was higher than that of conventional latexes.
 In this report we describe the characteristics and application of PVA-g-Latexes as water resistance papers with results of structural analysis.

A Report on ABTCP-TAPPI 2006
-39th Pulp and Paper International Congress & Exhibition-

Kunitaka Toyofuku

 The 39th ABTCP Pulp and Paper International Congress & Exhibition was held in Sao Paulo, Brazil on October 15-18, 2006 co-hosted by ABTCP and TAPPI.
 There were 8 special presentations by representative of association of the world and 68 general presentations on 6 sessions.
 Reflecting of positive overseas activity of ABTCP and growth of Brazilian pulp & paper industry, there were quite many presentations from foreign countries.
Special mention is enormousness of the attached exhibition. In the area of 10,000m2, 250 exhibitions were performed.
 After the meeting, I visited eucalyptus afforestations, Cenibra in Brazil and each subsidiary company of Nippon Paper Industries and Mitsubishi Paper Mills in Chile.

Effect of Surface Properties of Base Paper on Print Quality
-Application of Pre-calendering at High Temperature-

Hiroshi Koyamoto and Koji Okomori
Nippon Paper Industries Co., Ltd.

 The uniformity of coating layer is one of the most important properties of coated paper in terms of the print quality. If the coating layer is not uniform, poor print qualities such as mottling in offset printing might be occurred. The uniformity of coating layer is affected by surface properties of base paper such as roughness and porosity, and penetration of coating color into base paper. Pre-calendering is used to improve these properties of base paper, which leads to better coverage and uniformity of coating layer. For the pre-calendering of base paper, hard nip calender has been widely used. On the other hand, hot soft nip calender (HSNC) has been used as post-calender for coated paper. Comparing with conventional method like supercalender or soft nip calender (SNC), HSNC has advantages as followings, 1) increase of paper density is relatively small, 2) smoothness is higher at the same calendering linear load. In this study, the effect of HSNC for pre-calendering was investigated by comparing with/without pre-calendering using SNC (the temperature was different from HSNC). As a result of this comparison, mottling of LWC was improved by pre-calendering using HSNC. The base paper pre-calendered with HSNC has smaller pore diameter on the surface than that with supercalender or SNC. As a consequent, the coating coverage of base paper was improved by HSNC.

Keywords: Pre-calender, Hot soft nip calender (HSNC), Coated paper, mottling