2005年2月 紙パ技協誌

Newsprint in the Press

Masakazu Akatsuka
Hiroshima Research and Development Center, Mitsubishi Heavy Industries, Ltd.

Objectives of this paper are to discuss newsprint in the newspaper printing press through introducing the structure and function of the press, paper behavior in the press, and characteristics of newsprint.
It is possible to assume paper as elastic film with variation of elastic modulus upon water absorption through the printing process. Surface strength must be increased to reduce piling problem while brightness of paper must be similar among papers to be used in many sites to keep consistent print quality across the nation. It is also important to evaluate characteristics of paper under the condition corresponding to the actual operation.

Advanced Forming Fabric Technologies for Each Paper Grade

Hiroyuki Nagura
R & D Div., Nippon Filcon Co., Ltd.

According to our market research in Japan, while the forming fabric market has been shrinking annually, the number of forming fabric designs has been increasing every year. In this market situation, we would like to explain what kinds of forming fabric design are more popular for each paper grade, how they changed in comparison with 5 years ago, what the main factors to decide the direction of those changes are and what advanced forming fabric technologies for leading them are. Also, at the viewpoint of R&D, we would give some suppositions regarding the trends of new forming fabric technologies for future challenges and their solutions.

The Latest Development and Trend of Seamed Felt

Makoto Saito and Hiroshi Abe
Albany Nordiskafilt KK

 During the seventies, papermakers expressed their need for a press felt with seam, to make the felt installation easier. The reason for this was that the development of felt with seam had moved forward and the base weaves now contained both MD/CD with single monofilaments. With the single monofilament base weaves, the felt construction became stiffer and by that harder to install.
 More than 20 years ago, the dream became reality, and the first press with seam was installed at PM9-2P in Skarblacka, Sweden, producing a Kraftsack paper. The year was in 1982 and the trial was successful. The rumor was spread around and its future expectation became very positive for paper makers. The design of seamed felt was patented, but many of the licenses were sold to interested competitors to promote the development.

About The DOCTOR SYSTEM for Wire and Press Part

Shunich Hagita

  COUCHDOCTOR effective to the prevention of the occurrence of the mist and the hole obstruction and the improvement of the water profile.
DOCTOR FOR CERAMICS is doing DOCTORING enough, using a shower.
A big fault of all DOCTOR is Dregs stick to the reverse side of BLADE. However, it could remove by SELF developed afresh. If you use SELF CLEANING DOCTOR together with DOUBLE DOCTOR, a bigger effect can expect

Introduction of Trinippress into Paper Machine for Corrugating Medium

Toshihiko Ohara
Amagasaki Mill, Rengo Co., Ltd.

Amagasaki Mill No. 8 Paper Machine (PM No.8) of Rengo is manufacturing corrugating medium, basis weight from 115g to 200g.
The paper machine installed in 1979. The wire part was remodeled into Twinwire Duo Former F in 1987. As for the press part, we had not remodeled since the first. However, currently the press part became too old, and February 2002 which was renewed.
At selecting the new type of press section, we mainly took into account the improvement of runnability and energy saving by dehydrating at the end of press part. As a result, we decided to introduce the trinippress to the paper machine despite no performance of the introduction in the paperboard field.
In this report, I would like to report on the outline of the installation of trinippress and the current operating condition of PM No. 8.

Rebuild of Headbox & Ontop-Former at No.7PM

Hideya Takizawa
Iwakuni Mill, Nippon Paper Industries Co., Ltd.

No.7 paper machine at Iwakuni mill, Nippon Paper Industries, has been in operation since 1987.This machine has a 408-ton production capacity of coatbase paper per day, and has played the core role in our mill, the specialty being the high quality coated paper.
In January, 2004, the wet section was modified in order to enhance the sheet quality of coatbase.With this project, the Sym Flow-D headbox with advanced dilution control system and Sym Former-MB with a loadable blade module, being supplied by Metso-SHI Co., Ltd. allowed us to achieve a higher level of MD and CD quality and sheet formation.
This article introduces the latest operating experience, focusing on effects of this project.

Progress of OptiConcept Paper Making Machine

Hiroaki Tagashira
Metso SHI Co., Ltd.

Since 1st OptiConcept complete news print machine started in China, 10 complete OptiConcept machines have already started. One of the main targets of the OptiConcept was to combine all paper making processes into one paper making line.
The concept was realized by development of OptiSizer as for the coating unit and OptiLoad as for the on line multi nip calender. There are 4 complete LWC machines are running with this concept. In addition to the development of all online concepts, further development of section technology has been continued. Result of the latest development, such as new OptiFlo headbox, OptiDry vertical dryer and OptiSpray coating are introduced.

The Investigation of the Elution Tests of the Fluorescent Whitening Agents Contained in the Paper Packing Container for Foodstuffs

Takashi Miyagawa, Masayuki Omatsu and Takayuki Jikibara
Material Analysis Center, Oji Paper Co., Ltd.

Naoto Arai
Environmental Affairs Dep., Oji Paper Co., Ltd.

We requested some analytical organizations to carry out the fluorescent whitening agents examination of the papers, which have possibility to contact with foodstuffs directly. Although the examination was performed based on the official standard method, Kansyoku No.244, there was a considerable difference in the results obtained from the examinations carried out by various organizations. Kansyoku No.244 examination is performed as follows.
First, the specimen is extracted with weak alkali water. Then, the pH value of extract is adjusted between pH3 and pH5 with diluted HCl solution, and the gauze is dipped in the above extract. Finally, the gauze is observed under UV lamp to judge whether fluorescent whitening agents are extracted or not. In this investigation, it was found that the fluorescent whitening agents efficiently stained the gauze in strong acid water, but were little in weak acid and alkali water and the observer’s abilities of recognizing the fluorescence was difference, respectively.
The different results of the examinations carried by the analytical organizations were caused by the difference in pH, at which the gauze was dipped in the extract, and the observer’s ability of the recognition of the fluorescence.

The Development of MJ Former for Paperboard Grade

Akihito Nagano
Mitsubishi Heavy Industries, Ltd., Paper & Printing Machinery Division

Hiroshi Iwata and Kazuhiko Masuda
Mitsubishi Heavy Industries, Ltd., Hiroshima R&D Center

Production increase and the trend toward to lighter weight have been prevailing rapidly in the packaging industries on high speed operation. On the other hand, to increase an efficiency of the production, the number of multi-ply layers is reduced by heavier base paper.
Mitsubishi Heavy Industries has developed a new Roll Blade former to respond these market requirements. This new former has high drainage capacity, operational flexibility and gives excellent paper quality.
The first installation will be start-up in April 2005 in Germany.

Development of Biopulping Process with Cellulolytic Activity Suppressed Coriolus hirsutus

Seiji Nakagame, Mari Kabuto, Toshiko Sakaguchi, Sayaka Nakao, Akira Tsukamoto and
Jun Sugiura
Oji Paper Co., Ltd., Advanced Technology Research Laboratory

Biopulping, defined as a treatment of lignocellulosic materials with lignin-degrading fungi prior to pulping, can reduce energy and chemicals during the pulp making process. Coriolus hirsutus, one of the lignin-degrading fungi, is a promising strain for biopulping, because it degrades lignin efficiently and grows at higher temperature. However, C. hirsutus can not be directly applied to biopulping, because the cellulolytic activity of this fungus brings about negative effects on both pulp yield and paper strength.
In the present work, we cloned several cellulolytic genes of C. hirsutus and constructed a tandemly arranged antisense gene to suppress cellulolytic activities by the genetic modification. The transformants carrying a tandemly arranged antisense gene have lower cellulolytic activity than the host strain. Application of this treatment to wood chips has successfully led to higher cooking yield in chemical pulping without any negative effects on paper strength.

Experiences of Carbonizing Furnace of Paper Waste Sludge

Nobuyuki Shirahama
Sendai Mill, Chuetsu Pulp & Paper Co., Ltd.

Sendai Mill has produced carbonized paper-waste sludge, burned directly in sludge kiln, and sell for soil improving material and insulation for steel production for long time. We replaced a new carbonizing facility instead of old kiln, due to a decrepit facility and response to waste disposal and public cleaning law.
 On this line, dewatered paper sludge is pelletized in zouryuuki, dried to 10% water content, and distilled to dry carbonized materials by indirectly-heated carbonizing kiln. Exhaust gas produced in this distiller is burned in furnace for the purpose of the use of heat content of sludge. This facility is not regulated within dioxin relevant laws, because of a sludge-carbonization facility. But we placed this facility designed with the enough idea of dioxin rules on the structure.
 We report about facility characteristics, operation after starting on Nov. 2002, and product properties.

Operating Experience of Finishing Plant, Fuji N-2 Paper Machine

Mikiya Suzuki
Fuji Mill, Oji Paper Co., Ltd.

In 2001, we reformed the production system of white lined board. In the papermaking plant, two former machines were stopped and N-2 machine, the fastest machine for white lined board was built.
On the other hand, in the finishing plant, in order to deal with planography products that is 80% of all products, four sheeters and three packagers were installed.
The new main point is the perfectly automated transport system in the finishing plant.From N-2 machine to sheeters, the transport is automated by conveyers and a crane, and from sheeters to packagers, by conveyers and transporters.
In this article, we will report the new automated device and our operating experience.

Reports of 16th PTS CHT Symposium

Jiayi Chen
Pulp & Paper Industry Department, Kurita Water Industries Ltd.

16th PTS CHT (The Chemical Technology of Papermaking) Symposium took place in Munich, Germany during 15 to 17, September in 2004. 37 of research and technical paper were presented. They covered the innovation in pulping, papermaking, environment, chemicals and mechanical engineering. In this report, retention aid, water management and scale control were reviewed.

Reports of 2004 TAPPI Fall Technical Conference

Takanori Miyanishi
Fushiki Mill, Nippon Paper Industries Co., Ltd.

The 2004 Fall Technical Conference was held during October 31 ? November 3, 2004 in Atlanta, Georgia, USA. It was the joint conference of Pulping and Engineering. The huge conference provided 97 presentations in 39 sessions in 4 separate rooms. Topics of my interest included
・Workplace transformation.
・Opportunities for cost reduction in pulp manufacture.
・Improving bleach plant operation.
・Optimizing pulp mill operations through process simulations.

SEC-MALS Study on the Molecular Conformation of Modified Starches for Papermaking

Hiroshi Ono

Pulp and Paper Research Laboratory, R&D Division, Nippon Paper Industries Co., Ltd.
Masahiro Yanagisawa and Akira Isogai
Graduate School of Agricultural and Life Science, The University of Tokyo

Modified starches such as hydroxyethylated, acethylated, hydorhobic ester, and oxidized starches were widely used in papermaking industries as a surface strength agent or a binder of coating color pigment. However, the molecular conformation of these modified starches in aqueous phase was not fully understood. The purpose of this study is to investigate the molecular conformation of modified starches, which helps ideal chemical modification design for certain papermaking process.
Investigations based on size exclusion chromatography (SEC) and multi-angle laser light scattering (MALS) were conducted to assess the influence of chemical modification and degree of substitution (DS), molecular mass, and solubilization method on the macromolecular features in aqueous phase of modified starches for papermaking. SEC-MALS analysis revealed that increasing the DS value of hydrophilic group, decreasing the molecular mass by acid treatment or oxidation, and alkaline dissolution made the modified starch macromolecular more expanded conformation in water solution.

Keywords: modified starch, SEC-MALS, conformation, hydroxyethylated starch, surface strength