EP1774097A2 - Use of cyclodextrin for reducing yellowing of pulp and paper - Google Patents
Use of cyclodextrin for reducing yellowing of pulp and paperInfo
- Publication number
- EP1774097A2 EP1774097A2 EP05769014A EP05769014A EP1774097A2 EP 1774097 A2 EP1774097 A2 EP 1774097A2 EP 05769014 A EP05769014 A EP 05769014A EP 05769014 A EP05769014 A EP 05769014A EP 1774097 A2 EP1774097 A2 EP 1774097A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- cyclodextrin
- pulp
- paper
- yellowing
- chromophore
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/20—Macromolecular organic compounds
- D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
- D21H17/24—Polysaccharides
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/001—Modification of pulp properties
- D21C9/002—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives
- D21C9/005—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives organic compounds
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
- D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
- D21H21/143—Agents preventing ageing of paper, e.g. radiation absorbing substances
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
- D21C5/005—Treatment of cellulose-containing material with microorganisms or enzymes
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/02—Washing ; Displacing cooking or pulp-treating liquors contained in the pulp by fluids, e.g. wash water or other pulp-treating agents
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
- D21H17/005—Microorganisms or enzymes
Definitions
- the present invention relates to a method for preventing or reducing yellowing/brightness reversion of paper and pulps.
- Paper production involves, as a first step, the formation of pulp from wood.
- raw or pre-treated wood chips are "cooked" under high pressure and temperature in the presence of alkali and sulfide to dissolve the polymeric lignaceous material between the individual wood fibers.
- the liberated fibers still contain significant amounts of the colored lignaceous material within the fiber wall that can be removed to varying degrees via a spectrum of conventional bleaching operations/chemistries.
- the bleached wood fiber may contain various amounts of residual lignin and extractives (e.g. resin acids, fatty acids, triglycerides, terpenes, terpenoids, waxes, etc.).
- Paper and pulps prepared from bleached fiber containing trace amounts of residual lignin and/or extractives have been associated with enhanced sensitivity to color/brightness reversion upon exposure to elevated temperatures. Such thermal extremes can be encountered during conventional shipping and storage operations or within the dryer section and at the paper reel winder as the bleached fiber is converted into the final paper end- product.
- heat-sensitive precursors of chromophores such as lignin, extractives, as well as oxidation, condensation and cyclization products of carbohydrate origin (e.g. 2-furfural, hydroxymethyl furaldehyde, etc.) can be converted to chromophores resulting in yellowing (color reversion) or brightness reversion of the end product which is undesirable. Therefore such chromophore precursors should preferably be removed from the pulp at washing stages throughout pulping, bleaching and papermaking operations.
- a more aggressive washing regime is required to remove such color-forming components and is accomplished by means of investment in new equipment and/or existing equipment upgrades. Not only does this generally correspond to increased water and energy consumption, additional washing may increase the yield loss.
- Another means to reduce the concentration of chromophores precursors is to incorporate an additional stage into the bleaching sequence which not only necessitates significant capital expenditure, but also requires the increased usage of chemicals. Regardless of the treatment, certain color- forming materials may still remain within the washed pulp (especially those of carbohydrate origin).
- the present invention therefore relates to a method for reducing or preventing yellowing/brightness reversion of pulp and paper during conditions associated with conventional use (e.g. storage, shipping, paper production, archiving, etc.) comprising entraping the chromophore precursors present in the pulp within cyclodextrin rings and removing the resulting inclusion complex, such as, during conventional washing by adding or generating the cyclodextrin before or during washing.
- conventional use e.g. storage, shipping, paper production, archiving, etc.
- the aspect of the present invention therefore relates to a method for reducing yellowing/brightness reversion of pulp and paper comprising direct addition of cyclodextrin to the pulp or in situ generation of cyclodextrin followed by a subsequent washing step to remove the formed cyclodextrin inclusion complexes.
- the present invention relates to paper production and to the reduction of yellowing and/or brightness reversion of the pulp or the paper product.
- Pulp can be prepared from wood (virgin pulp) in a conventional kraft pulping procedure as described above or from recycled paper. Frequently, pulp will be comprised of a combination of the two fibre sources. For the purposes of the present invention, any type of paper making process is relevant and/or any paper making pulp can be applied.
- the amount of pulp based on recycled paper relative to the total amount of pulp is at least 2%, or at least 4%, or at least 6%, or at least 8%, or at least 10%, or at least 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 or at least 95%.
- the part of the pulp which is not derived from recycled paper may be derived from mechanical pulping, chemical pulping, and any mixtures thereof, such as, chemi-mechanical pulping, thermo-mechanical pulping, chemi-thermo-mechanical pulping, etc.
- a papermaking pulp often comprises both recycled paper and fresh so-called virgin pulp.
- the source of recycled fibre can be any of the grades of recycled furnishes known in the art or mixtures thereof, as well as mixtures of recycled fibres with virgin fibres.
- Major grades of recycled fibre furnishes are for instance MOW (mixed office waste), SOW (sorted office waste), ONP (old newsprint), OMG (old magazines) and OCC (old corrugated containers).
- raw or pre-treated wood chips are "cooked” under high pressure and temperature in the presence of alkali and sulfide to dissolve the polymeric lignaceous material between the individual wood fibers.
- the liberated fibers still contain significant amounts of the colored lignaceous material within the fiber wall that can be removed to varying degrees via a spectrum of conventional bleaching operations/chemistries.
- the bleached wood fiber may contain various amounts of residual lignin and extractives (e.g. resin acids, fatty acids, triglycerides, terpenes, terpenoids, waxes, etc.).
- Extractives such as the hydrophobic fatty acids and esters are very problematic during paper making process. They can cause severe deposits on the process equipment. In addition, the presence of these extractive compounds has been associated with increased sensitivity to thermo-yellowing. Even after lipase treatment, the newly formed long chain fatty acids are still too hydrophobic to dissolve in the process water.
- Suspected heat-sensitive precursors of chromophore molecules within conventionally pulped and bleached wood furnishes include residual lignin and extractives as well as oxidation, condensation and cyclization products of carbohydrate origin (e.g. 2-furfural, hydroxymethyl furaldehyde, etc.). Formation of chromophores, in response to elevated temperatures, ultimately manifests as a "yellowing” or "brightness reversion" of the end- product. In most instances, chromophore precursors are lipophilic with limited solubility within the process water.
- a chromophore comprises any compound which will give rise to a coloring of the pulp or paper.
- the chromophore can be formed from a chromophore precursor at elevated temperatures.
- Cyclodextrin may effectively entrap the chromophore and/or chromophore precursor and enhance their solubility in water. This corresponds to enhanced removal of the chromophore/chromophore precursors from the pulp at the washing stage.
- many of the precursors adversely affect certain physical properties of paper (i.e. tear, tensile, bulk, etc.) but physically disrupting interfiber interactions through adsorption onto the fiber surface.
- Enhanced removal through formation of complexes with cyclodextrins may enable a degree of recovery of any number of these affected properties.
- cyclodextins The most important feature of cyclodextins is their ability to form solid inclusion complexes (host-guest complexes).
- the lipophilic cavity of cyclodextrin molecules provides a micro-environment into which an appropriately sized non-polar moiety can enter to form an inclusion complex.
- Inclusion in cyclodextrins exerts a profound effect on physiochemical properties of guest molecules as they are temporarily locked or caged within the host cavity, which give rise to some unique beneficial modifications of the guest molecules.
- the properties include solubility enhancement of highly insoluble guests, stabilization of labile guests against the degradation, masking off flavours, and controlled release of drugs and flavours.
- solubility enhancement of entrapped chromophore/chromophore precursor molecules is utilized.
- Cyclodextrin may effectively entrap those hydrophobic materials and enhance their solubility in water. Cyclodextrin can also work with lipases and other enzymes to improve the efficiency.
- the paper making process comprises the following steps: a) preparing a pulp from wood and/or material comprising recycled paper; b) adding or in situ generating cyclodextrin; c) washing; d) making paper from the treated pulp.
- steps a)-d) further, optional, steps may be included, for example one or more of the following steps: e) treating the pulp with one or more enzymes; f) de-inking, e.g. by pulping the fibres in the presence of an aqueous alkaline solution, optionally containing a peroxide compound, such as hydrogen peroxide; g) separation of the fibres from the contaminants, e.g. by screening (coarse and/or fine); h) centrifugal cleaning; i) flotation, e.g. using one or more surfactants; j) washing, e.g. using one or more surfactants; k) dispersion; e.g. using one or more surfactants; and/or
- the enzyme may be introduced prior to the pulping, during a pulping stage, during or before, preferably right before, a stock preparation stage, or after a flotation or a de-inking stage.
- a purpose of the present invention is therefore to provide a method for reducing yellowing of pulp and paper comprising adding to the pulp or in situ generating cyclodextrin followed by a subsequent washing step to remove the formed cyclodextrin inclusion complexes from the pulp.
- the formation of the cyclodextrin inclusion complexes may also disrupt the conversion of the entrapped chromophore precursors.
- Cyclodextrin may be used in the form of alpha-, beta-, and gamma-cyclodextrin. In one particular embodiment the cyclodextrin is alpha-cyclodextrin. Cyclodextrin should preferably be present during washing of the pulp but can be added at an earlier stage. In one embodiment cyclodextrin is added during pulp formation. In another embodiment cyclodextrin is added after pulp formation but before washing. In still another embodiment cyclodextrin is added during washing.
- the ratio of fatty acid to cyclodextrin is in one embodiment in the range from 10:1 to 1 :100, particularly from 5:1 to 1:75, even more particularly from 2:1 to 1 :50.
- cyclodextrin instead of adding cyclodextrin it could also be generated in situ, e.g. generated in the pulp from starch and glycosyltransferase (CGTase).
- CGTase glycosyltransferase
- the cyclodextrin is generated in situ from starch and glycosyltransferase.
- enzymatic treatments may be employed as are well known in the art of paper making and include enzymes selected from the following group of enzymes: proteases, amylases, pullulanases, lipases, hemicellulases, endoglucanases, cutinases, and pectinases; as well as any combination thereof.
- the present invention therefore relates to the combination of enzymatic treatment of pulp with addition of cyclodextrins.
- Suitable enzymes are enzymes that will facilitate the release and complex formation of the chromophore or chromophore precursors.
- Xylanase is known in the art as an enzyme capable of reducing yellowing of pulp and paper.
- the cyclodextrin treatment of the pulp is combined with a xylanase treatment.
- Example 1 Improved thermo stability of bleached eucalvpt kraft pulp (BEKP) by addition of alpha-cvclodextrin
- Launder-Ometer beakers (The Launder-Ometer (Atlas Electric Devices Company, Chicago, IL, USA) is a standard piece of equipment used in the textile industry that spins the beakers, end-over-end, within a pre-heated, .water-filled chamber.) containing 400 g of 5% w/w consistency BEKP were prepared (the initial pH of the pulp was not adjusted prior to cyclodextrin application).
- alpha-cyclodextrin was aliquoted to each beaker according to the chart above to achieve the desired final concentrations.
- the handsheets were then "aged” for 15 minutes at 160 0 C and the optical qualitative measurements repeated.
- thermo stability of BEKP was improved resulting in a reduction in yellowing of pulp pads by the addition of alpha-cyclodextrin.
- Linoleic acid is the most abundant fatty acid in wood extractives and constitutes a potential chromophore.
- a 0.1% linoleic acid suspension and a 1.0% alpha- cyclodextrin solution was prepared as follows:
- Linoleic acid solution stays suspended as long as agitation is continued.
- a 1.0% alpha-cyclodextrin solution was prepared by dissolving 2 g of alpha- cyclodextrinin 200 ml deionized water.
- the 0.1% linoleic acid suspension was mixed with the 1.0 % cyclodextrin solution at different ratios of fatty acid to cyclodextrin and the increase in turbidity was determined.
- the results are given in the Table 2 below.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US58600404P | 2004-07-07 | 2004-07-07 | |
PCT/US2005/024156 WO2006014563A2 (en) | 2004-07-07 | 2005-07-07 | Use of cyclodextrin for reducing yellowing of pulp and paper |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1774097A2 true EP1774097A2 (en) | 2007-04-18 |
Family
ID=35787656
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP05769014A Withdrawn EP1774097A2 (en) | 2004-07-07 | 2005-07-07 | Use of cyclodextrin for reducing yellowing of pulp and paper |
Country Status (9)
Country | Link |
---|---|
US (1) | US20080041541A1 (en) |
EP (1) | EP1774097A2 (en) |
JP (1) | JP2008506046A (en) |
CN (1) | CN101124362A (en) |
AU (1) | AU2005269835A1 (en) |
BR (1) | BRPI0512990A (en) |
CA (1) | CA2572918A1 (en) |
NO (1) | NO20070657L (en) |
WO (1) | WO2006014563A2 (en) |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20060124266A1 (en) * | 2004-11-23 | 2006-06-15 | Novozymes North America, Inc. | Use of cyclodextrins for reducing deposits during paper production |
JP5214248B2 (en) | 2005-02-15 | 2013-06-19 | ジョージア テック リサーチ コーポレイション | Method for changing the stickiness of a substance |
US8512523B2 (en) * | 2006-02-14 | 2013-08-20 | Georgia Tech Research Corporation | Method for altering the tack of materials |
CN101784722A (en) * | 2007-06-28 | 2010-07-21 | 巴科曼实验室国际公司 | Use of cyclodextrins for odor control in papermaking sludges, and deodorized sludge and products |
JP6694651B2 (en) * | 2014-11-07 | 2020-05-20 | 日本食品化工株式会社 | Oil-based ink remover and method for producing the same |
JP7131296B2 (en) * | 2018-10-26 | 2022-09-06 | 王子ホールディングス株式会社 | Fine fibrous cellulose-containing composition and method for producing the same |
WO2020132120A1 (en) * | 2018-12-18 | 2020-06-25 | North Carolina State University | Fast disintegrating paper products and methods of making |
Family Cites Families (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1717799A (en) * | 1924-04-16 | 1929-06-18 | Robert A Marr | Pulp product |
US3426011A (en) * | 1967-02-13 | 1969-02-04 | Corn Products Co | Cyclodextrins with anionic properties |
US3453259A (en) * | 1967-03-22 | 1969-07-01 | Corn Products Co | Cyclodextrin polyol ethers and their oxidation products |
JPS636196A (en) * | 1986-06-26 | 1988-01-12 | 柴内 裕子 | Production of paper |
US5176796A (en) * | 1988-12-13 | 1993-01-05 | Jujo Paper Co., Ltd. | Avoiding pitch troubles using acylgerol lipase |
US5354424A (en) * | 1989-02-10 | 1994-10-11 | Rha Chokyun | Paper composition and methods therefor |
DK131193D0 (en) * | 1993-11-23 | 1993-11-23 | Novo Nordisk As | |
US5776842A (en) * | 1994-06-23 | 1998-07-07 | Cellresin Technologies, Llc | Cellulosic web with a contaminant barrier or trap |
RU2223985C2 (en) * | 1997-07-23 | 2004-02-20 | Циба Спешиалти Кемикалз Холдинг Инк. | Inhibition of cellulose and paper yellowing by the use of nitroxides and other simultaneously introduced additives |
ES2219861T3 (en) * | 1998-09-22 | 2004-12-01 | Alfred Pohlen | PROCEDURE FOR THE ELIMINATION OF STICKY IMPURITIES OF PAPER PASTE OBTAINED FROM PREPARED OLD PAPER, BY MINERALS CONVERTED TO HYDROPHOBES. |
US6689378B1 (en) * | 1999-12-28 | 2004-02-10 | Kimberly-Clark Worldwide, Inc. | Cyclodextrins covalently bound to polysaccharides |
AU2002253937A1 (en) * | 2001-02-12 | 2002-08-28 | The Procter And Gamble Company | Soil redeposition inhibition agents and systems |
US6849156B2 (en) * | 2001-07-11 | 2005-02-01 | Arie Cornelis Besemer | Cationic fibers |
DE10149313A1 (en) * | 2001-10-05 | 2003-04-17 | Bayer Ag | Use of aqueous brightener preparations to lighten natural and synthetic materials |
US20050107282A1 (en) * | 2002-11-14 | 2005-05-19 | The Procter & Gamble Company | Wipes and their use |
US7282113B2 (en) * | 2004-11-17 | 2007-10-16 | Tritexco, Inc. | Method for enzymatic deinking of waste papers, the waste papers so treated and the treating composition |
US20060124266A1 (en) * | 2004-11-23 | 2006-06-15 | Novozymes North America, Inc. | Use of cyclodextrins for reducing deposits during paper production |
US20060142432A1 (en) * | 2004-12-29 | 2006-06-29 | Harrington John C | Retention and drainage in the manufacture of paper |
EP1874993A4 (en) * | 2005-04-13 | 2008-10-29 | Novozymes North America Inc | Methods for reducing chlorine dioxide associated corrosion |
-
2005
- 2005-07-07 EP EP05769014A patent/EP1774097A2/en not_active Withdrawn
- 2005-07-07 BR BRPI0512990-7A patent/BRPI0512990A/en not_active IP Right Cessation
- 2005-07-07 US US11/571,638 patent/US20080041541A1/en not_active Abandoned
- 2005-07-07 WO PCT/US2005/024156 patent/WO2006014563A2/en not_active Application Discontinuation
- 2005-07-07 AU AU2005269835A patent/AU2005269835A1/en not_active Abandoned
- 2005-07-07 JP JP2007520511A patent/JP2008506046A/en active Pending
- 2005-07-07 CN CNA2005800230430A patent/CN101124362A/en active Pending
- 2005-07-07 CA CA002572918A patent/CA2572918A1/en not_active Abandoned
-
2007
- 2007-02-05 NO NO20070657A patent/NO20070657L/en not_active Application Discontinuation
Non-Patent Citations (1)
Title |
---|
See references of WO2006014563A2 * |
Also Published As
Publication number | Publication date |
---|---|
WO2006014563A2 (en) | 2006-02-09 |
NO20070657L (en) | 2007-02-06 |
AU2005269835A1 (en) | 2006-02-09 |
JP2008506046A (en) | 2008-02-28 |
CN101124362A (en) | 2008-02-13 |
US20080041541A1 (en) | 2008-02-21 |
CA2572918A1 (en) | 2006-02-09 |
BRPI0512990A (en) | 2008-04-22 |
WO2006014563A3 (en) | 2007-09-13 |
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