[Note: The classification number that follows each entry is an aid to indexing and finding citations by subject. Addresses of publishers like TAPPI , IPST or Pira can be found in the list of Useful Addresses sent out to each subscriber. To find out how to get a copy of a given paper, call the Abbey Publications office.]
Lockwood-Post's Directory of the Pulp, Paper and Allied Trades, 1998 ed. To appear Nov. 1997. $277 (item # 158-001) + $7 shipping in the U.S., $9.50 to Canada. Travel ed. $232. Call 1-800/848-5594 to order.
This is the venerable heavy-duty reference book that covers the paper industry: not just paper mills in the U.S., but paper and pulp mills, converters, distributors, suppliers, and mill officials in both the U.S. and Canada, as well as other information, e.g. a list of watermarks and brand names. For each mill it gives address, phone number, officials, principal machinery, products and tonnage produced. The industry changes rapidly; 4,600 listings have been changed since the 1997 directory. (1C4.4)
Paper Buyers' Encyclopedia and Competitive Grade Finder Pocket Edition for 1997/98 have been published. The Encyclopedia costs $95 in book form and $150 on disk. Order by fax from 610/524-8912 (Grade Finders Inc., 662 Exton Commons, PO Box 944, Exton, PA 19341).
This is a comprehensive guide for buyers of printing papers. It lists all the papers on the market by type (e.g., recycled offset, embossed, cotton content) and lists features of each paper in tabular form--including whether it is alkaline. There are also sections for manufacturers, converters, suppliers and grade classifications. (1C4.5)
"Simpson Reduces Machine Downtime with Automated Water Disinfection," by Garry Bohren and Jerry Weisenfelder. Pulp & Paper, Aug. 1997, p. 75-76.
Control of microorganisms in mill process water is a bigger problem with alkaline than with acid papermaking, the authors say, because the acidic environment acts as a natural disinfectant. In Simpson's Anderson, California, fine paper mill, they found that manual dosing of the shower water with gaseous chlorine did not give close enough control, because they still had occasional sheet breaks. Switching to an automated system allowed them to maintain a low consistant chlorine level of 0.3 ppm. (This is pretty low. The city water in Austin contains 27 ppm.) Now they have no sheet breaks from microorganisms, and no corrosion from excess chlorine. (2H2.10)
"Effect of Paper Properties on Fusing Fix," by D.J. Sanders, D.F. Rutland and W.K. Istone. J. Imaging Sci. Technol. v. 40 #2, Mar.-Apr. 1996, p. 175-179. (PBA Abstract 4619, 1997).
In order to select a test that could predict fuser fix in photocopies accurately, the authors tested 25 model papers with a variety of size, filler and surface treatment. Measurements of surface energy, surface tension, and surface composition were made on all of them, and fusing fix was quantified by crease tests. The crease width correlated significantly only with surface energy dispersive components. (3A9.2)
Spot Test Analysis, 2nd ed., by E. Jungreis. 1996. 400 pp. $69.95 from Cole-Parmer Instrument Co., 1-800/323-4340. Cat. # GY-15264-14, ISBN 0-471-12412-5. (3A9.7)
pH & Buffer Theory, by Rilbe [sic]. 1996. $84.95 from Cole-Parmer Instrument Co., 1-800/323-4340. Cat. # GY-15164-02; ISBN 0-471-96735. (3A9.7)
"The pH of New Library Books, 1976-1993: A Compilation of Survey Results," by Ellen McCrady. Abbey Newsletter v.21 #1, p. 1-3 1996 [i.e., 1997]. Nine surveys, 1981 to 1993, are summarized. One survey was done in Japan; one in a Utah public library, paperbacks only; one of medical serials only; and so on, so they are not easy to compare. Still, it seems safe to say that over 90% of hardcover books published in the U.S. are now alkaline. (3A9.8)
"On the Kinetics of Degradation of Cellulose," by A.M. Emsley et al. Cellulose v. 4 #1, Mar. 1997, pp. 1-5. (Paperbase Abstracts # 5346, 1997)
A unified model for the aging of cellulose in paper was derived, using the ModelMaker modelling package, which accurately represented the change in DP and in tensile strength with time. This model has replaced the Ekenstam (zero order) approximation, and gives more accurate predictions of the time it would take for DP to fall to very low values, when the tensile strength is critically low. This will allow better forecasts of the useful life of paper. (3B1.21)
"Alkaline Hydrolysis of Cellulose. (1). Without Chemical Additives," by A. Cochaux et al. Rev. ATIP 50, no. 4: 148-156 (Aug. 1996). (Abstr. Bull. IPST, Abstr. # 11490; also #12986, apparently an accidental duplication, 1996-97)
The effects of temperature, treatment duration, and buffer alkalinity on the alkaline hydrolysis of cellulose in cotton linters was investigated. The principal effect was breakage of glucosidic links; other effects were peeling reactions initiated by the hemiacetal functions on the end of the polymer. (3B1.21)
"Alkaline Hydrolysis of Cellulose. (2). Alkaline Hydrolysis with Anthraquinone," by A. Cochaux et al. Rev. ATIP 50 #5: 191-196 (Sept.-Oct. 1996). (ABIPST Abstr. 12987, 1997)
Anthraquinone does not affect alkaline hydrolysis of cotton linters in amounts under 1-2%. It is expected to accelerate delignification kinetics and increase pulp yields. (3B1.21)
"Identity of Crosslinks in Thermally Aged Paper," by D.C. Chamberlain and D.J. Priest. Cellul. Chem. Technol. 30, #3/4: 329-334 (May-Aug. 1996). (Abstr. Bull. IPST, 1996-97. For a copy of this paper or any ABIPST paper, send $18 to Institute of Paper Science and Technology, 500 10th St., NW, Atlanta, GA 30318, 404/894-5727, fax 404/894-4778, e-mail: firstname.lastname@example.org.)
The cause and effects of crosslinking during thermal aging of Whatman cotton chromatography paper was investigated. Dry-aged samples impregnated with aluminum salts (alum or aluminum chloride) were analyzed for wet and dry tensile properties, degradation, WRV and moisture regain. Results: the aluminum salt was necessary to catalyze crosslinking and degradation; higher concentrations and longer treatment times reduced moisture regain and WRV. Soaking of thermally treated samples in redox agents known to destroy crosslinking functions increased wet strength, especially for aluminum chloride-treated papers. Redox data eliminated aldehyde, aluminum and ester groups as causes of cross-linking, and pointed to ether linking. (3B1.21)
"Viscosity/DP Relationships for Cellulose Dissolved in Cuprammonium and Cupriethylene Diamine Solvents," by J.H. Morton. Chemistry and Processing of Wood and Plant Fibrous Materials (Biochemical Society and Chembiotech Ltd.): 151-158 (1996; Woodhead Publishing Ltd.). (ABIPST abstract 11503, 1997)
New viscosity/DP(w) equations relating cupriethylene diamine (CED) and cuprammonium testing to the DP(w) of cellulose in dissolving pulps derived from wood and cotton linters were established, and good agreement with existing measures was found. (3B1.21)
"Reversible Aging of Paper Measured by Near Infrared Spectroscopy," by C. Soremark and L. Wallbacks. Progress in Paper Physics - A Seminar, Stockholm, Sweden, 9-14 June 1996, pp. 69-70. (PBA Abstr. 3778, 1997)
A model was formulated "that predicts the time of aging at 50% relative humidity." [This part of the abstract is unclear, but it picks up when de-aging of a sample of kraft linerboard is described.] "After aging for 3 months the sample was de-aged by cycling it between 20 and 95% relative humidity twice, after which the aging process was carried out again. The de-aged sample returned to time zero and then followed the model for aging as before de-aging. This supports the theory that the aging process is reversible upon sorption/desorption of moisture." (3B1.21)
"The Influence of Mechanochemical Action on the Photosensitivity of Refiner Pulps," by J.H. Zhu et al., J. Pulp Paper Sci., v.23 #7, July 1997.
This is one of a great number of studies currently being done to discover the cause and prevention of color reversion in mechanical pulps. The research team tested the hypothesis that free radicals formed during mechanical pulping somehow increased the number of chromophores in the lignin, and found no evidence for generation of free radicals. Addition of radical scavengers during the refining process did not lead to brighter pulps or prevent yellowing. (3B1.4)
"Yellowing of Newspaper after Deacidification with Methyl Magnesium Carbonate," by Vladimír Bukovsky. Restaurator 18: 25-38, 1997.
An obstacle to long-term storage of newspapers in archives is that they darken significantly when deacidified. Cellulose is at least partially protected by deacidification against acid degradation, but what is happening with the lignin? The author reviews what is known about the role of photooxidation and free radicals in the darkening process and describes accelerated and natural aging (5.5 years) of deacidified and methanol-washed newsprint samples. First all samples were exposed to light for 185 days. This darkened the deacidified paper more than the other, but after aging it was the same or a bit brighter than the untreated paper.
Some of the conclusions: Deacidification of paper with methyl magnesium carbonate retarded oxidation by 39-50%. The presence or absence of acid in newsprint had no decisive impact on the degree of lignin oxidation and brightness reversion of paper during photooxidation. If the deacidified newsprint is later stabilized with sulphanilic acid, its tendency to oxidize at an increasing rate (due to an unstable linkage of the Mg with OH groups in the lignin) is significantly retarded. Mg, either in linkage with lignin or in the form of Mg ions, significantly retards oxidative degradation. Deacidification of newspapers with Mg is effective. (3B1.4)
"Minimization of the Brightness Loss due to Metal Ions in Process Water for Bleached Mechanical Pulps," by Y. Ni, Z. Li and A.R.P. van Heiningen. Paper given at the 83rd annual meeting of CPPA Technical Section, Jan. 28-31, 1997, Montreal. The preprints are in 2 vols., 725 pp. total, and cost C$80.00. ISBN 1-896742-10-6. (PBA Abstract 4467, 1997)
Brightness loss can be as high as 4 units if the process water contains metal ions present in concentrations typical of tap water. Heat-induced yellowing is also catalyzed by metal ions. Both kinds of yellowing are explained by the formation of colored complexes between lignin functional groups and metal ions. Addition of DTPA prevents most yellowing. (3B1.5)
"Acid Sizing with Calcium Carbonate," by M. Patel and J.C. Panigraphy. IPPTA v.8, #3, Sept. 1996, pp. 87-92. (PBA Abstr. 2824, 1997)
In India, a process has been developed for surface coating of calcium carbonate so that it can be used with acid sizing. Either PCC or GCC can be used. It is anticipated to be useful in small and medium size mills there. (3B1.7)
"A Linear Logarithmic Relationship of Yield vs. Kappa Number and Yield vs. Lignin Content for Sulphite, Kraft and Soda Pulps," by V. Masura. Cellul. Chem. Technol. v.30, #1-2, Jan.-Apr. 1996, pp. 81-94. (PBA Abstr. 2837, 1997)
Pulps tested were prepared by acid magnesium sulphite, acid calcium sulphite, magnefite, kraft and soda pulping of Norway spruce and beech woods. Yield was related to kappa number and lignin content by logarithmic straight line equations or power equations. (3B1.7)
A similar study was published in the next issue of Cellul. Chem. Technol. (no. 3-4, May-Aug. 1996, pp. 323-328): "Total Lignin vs. Kappa Number Relationship for Soda Pulps of Sugar Cane Bagasse," by M.G. Maximino and A.M. Adell.
"Yellowing of Coated Papers under the Action of Heat, Daylight Radiation, and Nitrogen Oxide Gas," by M. Mailly et al. Tappi Journal, May 1997, p. 176-183.
Coated papers tend to yellow because the latex (binder) in the coating is affected by daylight and certain gases like NO2 and NH3, which are found in coating pigments and dryer sections. Latexes testing in this study were radical emulsion terpolymers of styrene, butadiene, and acrylic acid terpolymers, which contained antioxidants and optical brighteners. Films of these latexes were aged in a Xenotest apparatus that gave off light matching sunlight; under another condition, UV was filtered out. They were also aged in the dark by NO2 (25 ppm) and NH3 (50 ppm) gases, at 20°C and 50% RH.
The study focussed on the yellowing of antioxidants used with latexes, and fluorescent agents used with coating colors (i.e., calcium carbonate and kaolin) under exposure to heat, humidity, daylight radiation, and NO2 and NH3 gases. Conclusions: Yellowing of coating layers is due to the presence of antioxidants and fluorescent agents. UV light also yellows them, but visible light bleaches them. NO2 causes pronounced yellowing of antioxidants containing hindered phenolic products, because of the formation of nitro derivatives such as nitrophenol, diphenoquinone, and stilbene quinone.
NO2 also yellows fluorescent agents and interferes with their effect. (3B1.8)
"Atomic Oxygen Removes Soot from Paintings," by C. Wu. Science News 150, Dec. 14, 1996, p. 372.
The Cleveland Museum of Art asked NASA to find a way to remove soot from paintings, because of the large number in storage after salvage from fires, presumably all over the country. Sharon Rutledge of NASA's Lewis Research Center in Cleveland reported at the Materials Research Society last year that they were able to clean a heavy smoke deposit from canvas prepared with gesso by "showering" or "bombarding" the surface with atomic oxygen in a vacuum chamber. (The oxygen in air is not atomic oxygen, but paired atoms.) It took from one hour to 23 hours to clean the surface, depending on the type of smoke. The oxygen combined with the carbon-based materials and formed carbon dioxide, carbon monoxide and water. (3B2.31)
"The Bleaching of Paper with the Borane Tert-Butylamine Complex," by Marina Bicchieri and Paola Brusa. Restaurator 18 no. 1, p. 1-11, 1997. Although this bleaching compound is hazardous and toxic, it can be used if safety precautions are taken. It works well to bleach previously oxidized paper, and to forestall subsequent oxidative degradation, which can take place at both acidic and alkaline pH. Treatment with the compound approximately doubled the degree of polymerization, intensified colors in the prints, bleached the paper, and brought the pH from 4.5 to 8.5. (From the Abbey Newsletter. 3B2.36)
"Progress in Alkaline Rosin Size," by J. Fallman, G. Pieh and M. Sychra. Progress '93: Needs and Possibilities of Paper Industry Development in the Countries Changing Their Economic System[s]: Conference Proceedings--Papers. (2). New Technologies and Equipment for Paper and Paperboard Manufacturing: 123-137 (1993; Stowarzyszenie Papierników Polskich).
The authors are from a Polish chemical manufacturing company, and they are describing and promoting their product, Sacocell 309. It is treated to reduce anionic charge and the content of reactive carboxyl groups. It can be used with calcium carbonate. (3B3.4)
"New Procedure for the Analysis of Alkyl Ketene Dimers in Paper and Its Future Development," by J.C. Roberts and M. Jaycock. PITA Conference: Papex International '93: Conference Proceedings: 10-13 (1993; PITA). (ABIPST Abstract 15116, 1997)
A new technique makes possible the sensitive measurement of on-machine retention of the unreacted forms of AKD. (Unreacted AKD makes paper surfaces slippery, which causes unstable rolls in the warehouse and feed problems in copiers and other machines. Richard R. Dunn, below, summarizes these problems as "slip, refold and welding problems at the converters.") (3B3.4)
"Trends and Advances in Alkaline Sizing," by Richard R. Dunn (of Nalco Chemical). Pima's Papermaker, June 1997, p. 88-89.
Until the end of 1993, AKD (alkyl ketene dimer) was the most popular alkaline size for uncoated freesheet, according to the author's bar graph on the first page; then ASA (alkenyl succinic anhydride) dominated, and by 1995 had become nearly twice as popular as AKD. Early AKD had some intractable problems, which were ameliorated later on: slow on-machine size development; cure rate variability; foaming at the wet end; and the need to supplement the internal sizing with a size press (surface) treatment in order to ensure adequate sizing.
Meanwhile, ASA's faults were being whittled down: emulsification and analytical capabilities were improved, and ASA's tendency to leave deposits were reduced to about the same level as AKD's. The polymer itself has been purified and free acid residuals greatly reduced; and today's understanding of retention and drainage mechanisms makes it much easier to keep the size in the paper all the way through the manufacturing process. (3B3.41)
"The Increasing Role of Calcium Carbonate in the Paper Industry," by K. Brooks and J. Meagher. Paper, v. 198, #5, Oct. 4, 1982 [sic], pp. 18, 21, 25-7.
This paper was published 15 years ago, long before Pfizer's acid-tolerant calcium carbonate was first marketed, but it describes a forerunner of that product . The abstract says, "Blue Circle Industries (BCI) has developed a safe and reliable means of using calcium carbonate in a rosin/alum system involving the protection of the calcium carbonate from acid attack. Recent research studies in America have predicted that neutral sizing will account for 25% of printing grades by 1986 and 55% by 1991. BCI polymer systems for achieving high filler levels are described." (3B3.44)
"Quality, Cost Benefits Spur Increased GCC Use by Paper Mills Worldwide," by Ken L. Patrick. Pulp & Paper, May 1997, p. 81-84.
Natural ground calcium carbonate use for filler and coating continues to increase in Europe, the U.S. and Asia. In Europe there are 31 factories, supplemented by strategically located tank farms (because it is often delivered in a slurry).
Here are the author's figures for alkaline freesheet production around the world: U.S., 72%; Europe, 95%; Japan, 35%; and Australia, 55-60%. He says about 30 paper machines in Europe and at least 10 in the U.S. are producing neutral (pseudo) high-groundwood-containing coating base stock, some of which will be coated with GCC. There are three forms of GCC: chalk, limestone and marble. All can be ground ultra-fine, with particles below 2 microns, which gives a high gloss to the coated paper. (3B3.44)
"Recycling Solution to Sludge Disposal," by J.A. Sohara. Pap. Equip. Mater. Int. v.6 #1, Jan.-Feb. 1997, p. 21. (PBA Abstr. 2804, 1997)
The down side of recycling is finding a way to dispose of deinking sludge. The author suggests incinerating it. This produces a mineral compound that is primarily calcium aluminum silicate, which can be recycled as a high quality filler--except that it is not as bright as PCC and is more abrasive. (3B3.45)
"Precipitation of Calcium Carbonate within Pulp Fiber Walls by Means of Carbon Dioxide Process at Low Pulp Consistency," by S. Siven, P. Silenius and M. Lindstrom. Publication 64, Lappeenranta [Finland] University of Technology, Dept. of Chemical Technology, 1996. 27 pp. 27 Finnish marks (about $5.50) (ISBN 951-764-028-5) (PBA Abstract 6099, 1997)
Calcium carbonate was precipitated in the cell walls of birch pulp fiber using the carbon dioxide process. (Presumably this was supercritical carbon dioxide, which can be used as a liquid solvent.) Result: greater bending stiffness of loaded pulp; more uniform filler distribution; but lower strength when prepared at lower consistency. (3B3.46)
"Fiber Loading: Environment, Energy, and Economics," by John Klungness. Progress in Paper Recycling, Aug. 1997, p. 79.
This is not an article, but a brief summary of ongoing or recently concluded research at the Forest Products lab in Madison, Wisconsin. It is in a section of the journal devoted to "Industry Needs and Institutional Research," which appears periodically and provides a very valuable service. Jeffrey Dyer is the editor of this section. Some of the research reports are by graduate students. Reports are grouped by sponsoring organization, and the author's (or graduate advisor's) telephone and fax numbers are furnished. At the end of this 16-page section is a brief summary of ongoing research, a summary of the recycling industry's needs, and a discussion of how closely they match.
This particular summary focuses on five aspects of the research project: handsheet properties, sludge production, drying cost differentials, comparative energy needs, and economic savings. More carbonate can be gotten into the paper, and less is lost as sludge during recycling. Fiber loading (sometimes called lumen loading) puts the filler compound into the lumen of the fiber as well as between the fibers, so it does not interfere as much with fiber bonding. It is estimated that it can save 2.26 x 1011 BTU/year for daily production of 500 metric tons of deinked pulp, which comes to about $3 million per year.
Another research summary by the same author in this section is "Fiber Loading Technology Transfer." A demonstration of fiber loading's use with recycled newsprint, printing and writing grades and top liner for linerboard will be set up by a technical partnership consisting of Voith Sulzer's Recycling Technology Center, Praxair, Inc. and inventors at the Forest Products Lab, in order to encourage adoption of this economical new process. (3B3.46)
Paper Recycling Challenge Vol. II, Deinking & Bleaching. Mahendra Doshi and Jeffrey Dyer, eds. $110 from Progress in Paper Recycling (ph. 920-832-9101). 300+ pages. The first volume in this series was Stickies, published in April 1997. (3B3.6)
"Environmental Groups ask Clinton to Stop Federal Purchases of Virgin Copy Paper," by Ken McEntee. , Oct. 1996, p. 1, 3-5.
Recycled paper accounts for only 16% of the paper purchased by the federal government, even though Executive Order 12873, signed four years ago, was intended to increase federal purchasing of recycled paper. Nineteen states buy more recycled paper than the federal government does, on a basis of percentage of their total paper purchases, and three of these buy nothing but recycled.
To make matters worse, from the environmentalists' point of view, the President had not been using stationery manufactured from genuine postconsumer waste; his stationery was made of cotton linters (which does qualify as recycled, according to the definitions published by EPA, but not as postconsumer content recycled paper).
The environmental groups who want the President to direct the GSA and GPO to stop selling virgin paper, and to start using stationery with 20% postconsumer fiber to set a good example, is coordinating its efforts through the Government Purchasing Project (GPP). They are focussing on copy paper, the largest category of paper used by the U.S. government.
There is no mention in this article, or in any other recent literature, about the need to consider permanence as well as recycled content in making paper purchases. Although the Executive Order has the status of law, so does the Permanent Paper Law, PL 101-423, as recognized by Fran McPoland, the Federal Environmental Executive in a letter to the president of the New York Public Library, published in the Congressional Record and in the Abbey Newsletter (Oct. 1994, p. 76).
Perhaps the fact that there is a published list of papers that are permanent and recycled (North American Permanent Papers, 1995) leads readers to assume they are home free if they use a recycled paper from the list. In most cases this is true, but for large purchases and important documents, customers should still do their own testing. The mill or distributor may have substituted an acid version of the paper ordered; or the person who filled out the questionnaire at the mill may not have understood the directions. The recycled content can change at any time, and the raw material (waste paper) is sometimes unpredictable in nature and quality. (3B3.6)
"Chemicals [used in Papermaking]" Tappi Journal, July 1997, p. 68. This is simply a list of about 120 chemicals manufactured by TAPPI sustaining members, but it is in a handy form for anybody who just wants to know what kind of chemicals are used in papermaking. For a really comprehensive list, along with the suppliers of each chemical, see Lockwood-Post's Directory. (3B3.7)
"Classification of Groundwood Grades of Paper (From Newsprint to High-Grade Coated) with an Outlook for the 1990s," by A. Glassman. Pulp & Paper Canada 93:11 (1992), p. 48-51.
Classifications of paper change continuously, according to who is talking, who they are talking to, the purpose for which the paper is to be used; and new and revised kinds of papers are coming out all the time. Nevertheless, classification is necessary for purposes of communication and gathering of statistical data. Groundwood grades (stone groundwood, TMP, CTMP, and so on; also called "mechanical" grades) can be classified by process, product category, end use, product attributes/ characteristics, commercial acceptance, or by a new proposed standard. Europe, Japan, and North America all use different classifications. The author suggests using four criteria for groundwood content grades: 1) specifications, without regard to process, 2) broad categories, like newsprint LWC (lightweight coated), 3) end use, and 4) performance. (3B3.71)
"The Oversized Rubiks Cube," by E.P. Duffy. Paper Age v. 113 #5, May 1997, pp. 26-27. (PBA Abstr.6144, 1997)
The "Rubiks Cube" symbolizes the difficulties of classifying paper, among them grade fragmentation, variations in supply and demand, and new grades. The six sides of the cube represent the six main principles by which paper can be--and is--classified: paper manufacturing, end uses, distribution channels, print processes, advertising and promotion, and "other," which is broken down into seven more factors. The reader, if he gets this far, may feel like agreeing with the author when he says, "In the light of these considerations, grade classifications are a minor issue." (3B3.71)
"Crisp Imagery for Newsprint," by Stephen Verosko. Pima's Papermaker, July 1997, p. 62-63.
Papermakers are now sizing newsprint, and using retention and drainage aids, to help them make a quality sheet to carry clear text, color pictures, and detail. At the same time, they have to use more recycled fiber and less water. This is a supplier's report of a study on sizing of newsprint. Normally, with virgin pulp, newsprint does not need sizing because natural resins are retained in the pulp. With recycled pulp, however, the papermaker has to compensate by chemical means; otherwise, runnability is reduced and sheet breaks plague production. Another cause of sheet breaks is carryover of surfactants from the recycling process.
This study compared AKD and rosin sizing, and internal and surface size, for their effect on hydrophobicity and clarity of printed image, compared to a sheet with no sizing. Advantages of using AKD are less color reversion because there is no alum in the paper, and less foaming and deposits from unretained rosin. The clearest printed images and least show-through are from use of both internal and surface size in the same sheet. (3B3.74)
"Bleaching Issue: Discussion and Perspectives," by D. Lachenal. EUCEPA International Environmental Symposium (1). Pulp and Paper Technologies for a Cleaner World (EUCEPA). Plenary Lectures: 35-44 (1993). (ABIPST Abstr. 13997, 1997)
The author gives a mild and fairly rational endorsement of totally chlorine-free (TCF) bleaching, saying that chlorine dioxide is converted progressively into hypochlorous acid, which is partly transformed into chlorine depending on its pH value, but which does not cause production of highly chlorinated phenolics. So chlorine dioxide leads to less toxic bleach plant effluents. But it is easier to recycle bleach plant effluents if TCF is used. There are no acceptable methods for recovering effluents containing chloride ions. (3B3.83)
"Presenting the Facts: Look at Totally Chlorine-Free vs. Elemental Chlorine-Free [Bleaching]: Case for ECF [Bleaching]," by D.C. Pryke (of Alliance for Environmental Technologies). Recycled Paper News 7 #7: 1, 3-5 (April 1997). (ABIPST Abstr. 16959, 1997)
The author defends the use of chlorine dioxide in an elemental chlorine-free bleaching program: the pulp is brighter and stronger; dioxin discharges are substantially reduced. But he cites a 1996 study report by the International Institute for Environment and Development (London, UK) that concludes that there were no appreciable environmental differences between the ECF and TCF processes. (3B3.83)
"New Pulp Bleaching Technology May be on the Horizon," by Ken McEntee. Recycled Paper News, May 1997, p. 2-4.
This is a report of the Conference on Clean Paper Making Technologies for the 21st Century, held in April at Green Bay, Wisconsin, and sponsored by the Oneida Tribe of Indians of Wisconsin. The main focus of the conference (of course) was the ECF-TCF debate, involving the environmental activists present, but author McEntee says that the polyoxometalate delignification process described by a Forest Products Lab representative sounds like it will make that whole debate irrelevant by making closed-mill technology (no effluents at all) possible.
A speaker from International Paper gave a good defense of ECF bleaching. IP has converted all its bleach plants to ECF. (3B3.83)
"Neusiedler AG Begins Production of Hemp Paper." Wochenbl. Papierfabr. v. 125 #7, Mid-Apr. 1997, 388-390 (in German). (PBA Abstr. 6137, 1997)
"Hemptec" is a high quality copy paper from hemp that was launched by the Austrian company Neusiedler Actiengesellschaft in the first quarter of 1997. In all of Austria, only 900 hectares are devoted to hemp growing, which is about 1/7 of the acreage that would be needed to supply one pulp mill. (3B3.84)
"Utilizing Cellulon Cellulosic Fiber for Binding in Nonwoven Applications," by J.J. Miskiel. 1997 Nonwovens Conference, Memphis, 17-19 March 1997, pp. 101-104. (TAPPI Press, 1997, $59.85) (PBA Abstr. 5442, 1997)
Cellulon is a bacterial cellulose fiber that is very long, strong and thin. Because of its high surface area, it makes a good binder in specialty paper and nonwoven applications. Monsanto Performance Materials of San Diego is the supplier. (3B3.84)
"Focussing Scientific Excellence on Mechanical Pulping: The Mechanical and Chemimechanical Pulps Network," by H.J. Bolker. Pulp & Paper Canada 94:5, May 1993, p. T 133 - T 138.
This article is over four years old, but it gives a fairly complete description of the purpose, organization, projects and accomplishments of the Network, which had been founded two years earlier. Some of the findings are presented in five graphs and tables. (3B3.85)
Two papers published simultaneously in 1996 describe statistical/mathematical methods for finding the relationship between kappa number and lignin content for certain pulps at certain yields. Interestingly, they are from separate countries, Argentina and Slovakia. Both were listed in ABIPST, 1997 (abstracts 11069 and 11070). The citations are:
M.G. Maximino and A.M. Adell. "Total Lignin vs. Kappa Number Relationship for Soda Pulps of Sugarcane Bagasse." Cellul. Chem. Technol. 30, #3/4: 323-328 (May-Aug. 1996).
V. Masura. "Linear Logarithmic Relationship of Yield vs. Kappa Number and Yield vs. Lignin Content for Sulfite, Kraft and Soda Pulps." Cellul. Chem. Technol. 30, no. 1-2: 81-94 (Jan.-Apr. 1996). (3B3.87)
"Board Mill Conversion to the Alkaline Process," by D.J. Janigan, C. Cossette and L.G. Angell. A paper scheduled to be given at Paperweek Canada (78th annual meeting, Technical Section, CPPA, Jan. 1992), announced in Pulp & Paper Canada 92:12 (1991) p. 41. (3B3.87)
"Those Old Dioxin Blues: Some Small Fry are Exquisitely Sensitive Models of Dioxin Vulnerability," by Janet Raloff. Science News 151, May 17, 1997, p. 306.
Poisoning of fish in the Great Lakes by dioxins, polychlorinated biphenyls (PCBs) and related chemicals began in the 1930s. It peaked about 1970, at the same time that fisheries managers noticed that the offspring of apparently healthy fish were not able to survive to maturity. Trout were virtually extinct in Lake Ontario, the most polluted of the five lakes, by 1960.
After restocking for 25 years, as the pollutant levels fell, the fisheries have now seen their stock survive beyond the fry stage. As environmental offices continue to study the problem, however, new problems as well as new solutions become apparent. New lake contaminants have been identified that are at least as toxic as 2,3,7,8-chlorinated dioxin (TCDD), which until recently has been considered the most potent toxicant in this family. One of these newly identified contaminants is 2,3,6,7-tetrachloroxanthene, a component of paper mill waste that induces "blue sac" in lake trout fry (discoloration of the egg yolk sac attached to the young fry, as a result of exposure to TCDD). Another dioxin, used in a lamprey-killing compound in the Great Lakes, contains a chlorine atom and three fluoride atoms, among other chemical groups. Three research groups have discovered delayed effects of sublethal doses which indirectly cause death, such as the PCB damage to immune systems that contribute to large dieoffs in subsequent disease episodes.
Dioxin targets the cardiovascular system in both fish and mammals. In fish, it slows down the heart rate, prunes back blood vessels, interferes with ability to maintain the blood vessels, and induces oxidation. Antioxidants greatly reduce the damage done by dioxin. (3B3.9)
Timestamp: Sunday, 03-Mar-2013 21:42:54 PST
Retrieved: Saturday, 18-Nov-2017 04:50:19 GMT
Timestamp: Sunday, 03-Mar-2013 21:42:54 PST
Retrieved: Saturday, 18-Nov-2017 04:50:19 GMT