EP1957709A1 - Method of producing paper and cardboard - Google Patents

Method of producing paper and cardboard

Info

Publication number
EP1957709A1
EP1957709A1 EP06830916A EP06830916A EP1957709A1 EP 1957709 A1 EP1957709 A1 EP 1957709A1 EP 06830916 A EP06830916 A EP 06830916A EP 06830916 A EP06830916 A EP 06830916A EP 1957709 A1 EP1957709 A1 EP 1957709A1
Authority
EP
European Patent Office
Prior art keywords
pulp
hemicelluloses
xylan
bleached
paper
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Withdrawn
Application number
EP06830916A
Other languages
German (de)
English (en)
French (fr)
Inventor
Osmo Pekkala
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
UPM Kymmene Oy
Metsa Fibre Oy
Original Assignee
Keskuslaboratorio - Centrallaboratorium Oy AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Keskuslaboratorio - Centrallaboratorium Oy AB filed Critical Keskuslaboratorio - Centrallaboratorium Oy AB
Publication of EP1957709A1 publication Critical patent/EP1957709A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/22—Other features of pulping processes
    • 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
    • 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
    • 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

Definitions

  • the present invention relates to a method according to the preamble of claim 1 for producing paper and cardboard.
  • a bleached cellulosic pulp which comprises hemicelluloses on a paper or cardboard machine.
  • Bonding degree of the fiber network controls the mechanical properties of paper. The network would have no cohesion if there were too few bonds between the fibers. Thus, bonding degree of the fiber network should be increased to improve strength properties and runnability of paper.
  • the bonding between papermaking fibers is conventionally considered primarily to be due to hydrogen bonds.
  • Carboxylic groups are often components of hydrogen bonding.
  • High contents of carboxylic acid groups on fiber surfaces increases inter-fiber bond strength.
  • the concentration of acidic groups on the surface of the fiber has a relatively greater effect on bonding and tensile strength of the dried sheet than the total concentration acidic groups.
  • Uronic acid groups in hemicelluloses are the main carboxylic group constituents in wood.
  • the higher xylan content of birch wood compared, for example, to eucalyptus, makes a controlled manipulation of the xylan content in the fiber wall or on the fiber surface of pulp favorable with respect to tailor-make birch pulp properties for different paper and board grades.
  • Adsorbed xylan is claimed to contribute to the mechanical strength of paper by enhancing interfiber bonding [2].
  • Xylan also plays an important role in determining the chemical interactions between fibers, water, and a variety of chemicals used in the papermaking process.
  • the effects of xylan on the strength properties of pulps are claimed to depend on the degree of polymerization of xylan, the amount of xylan, its chemical structure as well as its distribution in the fiber wall [3].
  • Xylan located especially on the outer surface of fibers is generally considered to have an important effect on fiber-fiber bonding and thus on the strength properties of pulp.
  • Phenomena and effects of xylan resorption on pulp fibers have been reviewed and discussed in some studies. They include e.g. behavior of xylan during kraft pulping, mechanism and effects of conditions on resorption of xylan, distribution of the desorbed xylan in pulp and influence of the adsorbed xylan on the properties of pulp.
  • the present invention is based on the concept of reducing the hemicellulose content of bleached cellulosic pulp, such as bleached pulp of deciduous wood raw-material, by selectively removing an essential portion of the hemicelluloses, in particular xylans, contained in the bleached pulp to produce a modified pulp.
  • the hemicellulose can be extracted from the bleached pulp at alkaline conditions.
  • an alkaline agent such as an alkali metal hydroxide or carbonate, or a hydrolytic enzyme, such as xylanase, can be used.
  • the extracted xylane can be adsorbed onto the fibre surface of other papermaking pulps, such as pulps of deciduous and coniferous chemical pulps, chemimechanical pulps and mechanical pulps. Thereby an increased bonding between the fibres is reached and the strength properties of the fibrous mixtures or of the papers or cardboard manufactured therefrom is obtained.
  • the extracted hemicellulose can also be employed for producing various chemicals, such as furfural and xylitol from xylane. Even if a great number of studies have been carried on the adsorption of hemicellulose onto fibers and the influence thereof on the properties of the pulp, provision of hemicellulose by extraction of bleached pulp and its use for readsorption or for other uses has not been described in the art.
  • the method according to the present invention is mainly characterized by what is stated in the characterizing part of claim 1.
  • a more targeted chemical composition of pulp fibers can be achieved, when the adjustment of hemicelluloses in pulp fibers is carried out in one well-controlled stage after fluctuating cooking and bleaching stages.
  • hemicelluloses can be taken from one bleached pulp and transferred to another resulting in two pulps with varying properties, one pulp with properties related to low hemicelluloses content in the fiber wall and the other with properties related to high hemicelluloses content on the fiber surface (Fig. 1).
  • Location of hemicelluloses in fiber wall may be favorably influenced by this hemi-transfer.
  • the hemicellulose fraction removed from the bleached cellulose pulp can be utilized, for example for producing fine chemicals, such as pentose monomers or dimers, or the hemicelluloses obtainable from extraction of bleached cellulose pulp can be used at the wet end of the papermachine as a chemical in a fashion similar to starch.
  • the present invention concerns a method of producing paper or cardboard from bleached cellulosic pulp, which contains hemicelluloses.
  • the hemicellulose composition of bleached cellulosic pulps depends on the wood species and on the pulping conditions.
  • the term "hemicelluloses" generally covers comparatively short-chained polysaccharides consisting mainly of xylosyl-, glucosyl-, galactosyl-, arabinosyl- or mannosyl-residues.
  • the hemicelluloses are partially soluble, in particular in alkaline media.
  • the predominant hemicellulose component in deciduous wood species is xylan or xyloglucan, which typically contains glucuronic acid groups in position 4 of the anhydroxylose unit.
  • the acidic side chains of pulp xylan are not exclusively composed of the 4-O-methyl- [alpha] -D- glucuronic acid or [alpha] -D-glucuronic acid present in native wood, but an essential part of the 4-methyl glucuronic acids have during pulping been converted to an unsaturated derivate thereof, viz.
  • hemicelluloses present in bleached cellulosic pulps include glucomannan and arabinogalactan, the latter of which is typically present in coniferous wood materials.
  • the present invention particularly concerns the treatment of bleached cellulosic pulp comprising a pulp prepared by alkaline pulping of a raw-material predominantly composed of deciduous tree, such as a bleached cellulosic pulp prepared by kraft pulping or a similar pulping process of wood of the Betula species.
  • a bleached cellulosic pulp prepared by kraft pulping or a similar pulping process of wood of the Betula species.
  • kraft pulping the wood raw-material is cooked in an aqueous solution of sodium hydroxide and sodium sulfide, known as white liquor, to selectively dissolve the lignin.
  • white liquor aqueous solution of sodium hydroxide and sodium sulfide
  • the yield of kraft pulping is typically about 45 %.
  • Bleaching can be carried out with oxygen containing bleaching chemicals, such as ozone and peroxides, with chlorine containing bleaching chemicals, such as chlorine dioxide or chlorine gas, or combinations of these bleaching chemicals.
  • oxygen containing bleaching chemicals such as ozone and peroxides
  • chlorine containing bleaching chemicals such as chlorine dioxide or chlorine gas
  • the present invention is not limited to the use of kraft pulping in combination with conventional bleaching methods, but is extends to any combination of cooking with bleaching which produces a bleached pulp that contains a significant portion of hemicelluloses.
  • the hemicellose content is up to about 25 % by weight of oven dried material, a typical concentration in bleached pulp of deciduous wood species being about 15 to 22 % by weight.
  • a significant part of the hemicelMoses are removed by extraction before the pulp is used for making paper or cardboard.
  • significant part designates in this context a removal of, preferably at least 5 wt-% and less than 50 wt-%, in particular about 7 to 30 wt-%, of the hemicelMoses present in the pulp. Typically, some 8 to 20 wt-% are removed for the purpose of the present invention.
  • the extraction is typically carried out using an aqueous solution or dispersion of an alkaline substance or an enzyme or a mixture thereof. It is preferred to carry out extraction at a consistency of about 0.1 to 25 %, preferably about 0.5 to 20 %, in particular about 1 to 15 %.
  • an aqueous solution containing an alkaline substance can be employed, such a substance being selected from the group of alkali metal and earth alkaline metal hydroxides and carbonates or mixtures thereof.
  • an alkaline substance such a substance being selected from the group of alkali metal and earth alkaline metal hydroxides and carbonates or mixtures thereof.
  • pulping liquors or solutions e.g. bleaching or washing solutions
  • white liquor or green liquor can be particularly mentioned.
  • the aqueous solution contains 0.01 to 5 M of the alkaline substance, a preferred range of concentration being about 0.5 to 3 M for alkali metal hydroxides, such as sodium hydroxide.
  • the extraction with an aqueous solution or dispersion of an alkaline substance or a mixture of alkaline substances is, according to one embodiment, carried out at ambient temperature and pressure for 1 min to 24 hours, preferably about 5 min to 12 hours, in particular about 10 min to 6 hours. According to another embodiment, the extraction is carried out at an elevated temperature of 20 to 150 0 C for 1 min to 24 hours, preferably about 5 min to 4 hours.
  • the aqueous extraction solution can contain at least one hydrolytic enzyme capable of releasing hemicelMoses from the pulp.
  • hydrolytic enzymes are hydrolases selected from the group of hemicellulases and pectinases.
  • a particularly interesting group of enzymes comprises xylanases.
  • the hemicelluloses are selectively removed from the pulp essentially without degrading them.
  • the extraction liquor contains but a small proportion of mono- or disaccharides derived from the hemicelluloses.
  • the extracted pulps exhibit interesting and valuable properties, which can be utilized as such for making specific paper and cardboard products, as will be discussed below, the invention also provides for the use of the removed hemicelluloses.
  • the extraction products are therefore recovered and subjected to further processing.
  • the hemicelloses are recovered in the form of an aqueous dispersion or solution.
  • the hemicelluloses are contacted with cellulosic or lignocellulosic fibres under conditions conducive to adsorption of them onto the fibres.
  • the fibres which the hemicelluloses are adsorbed on include fibres of chemical, chemimechanical or mechanical pulps used for the production of paper and paperboard products.
  • hemicelluloses taken from a first bleached pulp can thereby transferred to a second, optionally also bleached pulp, resulting in two pulps with varying properties, one pulp with properties related to low hemicelluloses content in the fiber wall and the other with properties related to high hemicelluloses content on the fiber surface.
  • the same pulp can thereby be used for preparing two different kinds of paper or board qualities.
  • the hemi-transfer embodiment can be carried out by recovering the hemicelluloses in the form of an aqueous dispersion which then is fed as such, or optionally after concentrating or dilution to desired consistency, to the headbox of a paper or cardboard machine where they are contacted with the fibres in the furnish.
  • the hemicelluloses can be adsorbed onto the fibres at a consistency of about 0.05 to 20 %, preferably about 0.1 to 20 %, in particular about 0.5 to 10 %.
  • the adsorption of the hemicelluloses onto the fibers is carried out at alkaline conditions, preferably mildly alkaline conditions, the pH being about 7 to 13, in particular about 7.5 to 10. It is possible to operate at essentially neutral conditions, also. However, it has been found that the adsorb amount increases somewhat at increased pH.
  • the concentration of hemicelluloses in the aqueous dispersion or solution used for adsorption of hemicelluloses onto the fibres is preferably about 0.1 to 50 g/1, such as about 0.5 to 30 g/1, in particular about 1 to 20 g/1, more particularly about 1.5 to 15 g/1.
  • the recovered hemicelluloses comprise mainly xylan.
  • the hemicelluloses generally, in particular xylan, have interesting properties when adsorbed onto pulp fibres. In particular, it has been found that they can be adsorbed onto cellulosic or lignocellulosic fibres used for paper or cardboard in order to improve mechanical strength properties, including tensile strength, bonding and elasticity.
  • the method according to the present invention generally leads to a lowering of the total yield of the bleached cellulosic pulp by a maximum of 15 %, preferably by a maximum of 10 %, preferably about 1 to 8 % by weight.
  • the pulp can be used as a raw-material for the production of various paper and cardboard products, in particular uncoated and coated paper or cardboard products having a grammage of 25 to 500 g/m 2 , (for papers typically about 40 to 180 g/m 2 , and for cardboards typically about 180 to 450 g/m ) exhibiting one or several improved properties from the group of brightness, resistance against yellowing, drainability and water retention. These properties will also be discussed in more detail below.
  • the papers can be used e.g. as printing papers and the board materials e.g. as liners in FBB products.
  • One particularly interesting application of the invention is for the production of fine papers from the extracted pulp.
  • the extracted hemicelluloses represent an extremely pure raw-material - pure with respect to the polysaccharide composition and lacking extractives etc. - and they can be used as a raw-material for the manufacture of chemicals.
  • fine chemicals include, in the case of xylan, xylitol and furfural.
  • Xylitol is a sweetening agent with interesting properties and very diverse applications. Xylitol can be prepared from xylose in a batchwise, three-phase hydrogenation process. It is also possible to produce xylitol from xylose by fermentation. Furfural can be prepared commercially by dehydration of pentose sugars, such as xylose.
  • furfural is being use as a feedstock for furfuryl alcohol which is, again employed in the production of thermosetting furan resin and furan cement.
  • hemicellulose fraction (xylan) from one bleached birch kraft pulp and by transferring it onto another significant changes in chemical and physical properties of the fibers are achieved.
  • the technical properties of pulp for paper and board can be changed and usability of a bleached birch kraft pulp improved with respect to a plurality of paper and board grades.
  • Alkali extraction of a birch kraft pulp mainly removes xylan from the pulp and increases cellulose content and viscosity of the pulp.
  • the amounts of extractives are also
  • Fibers become lighter and their fiber width and wall thickness is reduced, indicating improved formation capability and reduced flocculation tendency of fibers in papermaking.
  • Sorption of xylan onto kraft pulp fibers have an opposite, but not as significant effect on fiber properties as the high xylan amount in polysulfide pulp fibers.
  • a reduced xylan content improves initial pulp properties like drainage, bulk and light scattering. Although some properties, like tensile strength, bonding, elasticity and dimension stability, are also to extent detrimentally affected, by subjecting the pulp to more beating aiming, e.g., at reaching a predetermined tensile strength level, many of these changes in pulp properties can be compensated. Sorption of xylan onto birch kraft fibers changes many pulp properties according to the same lines as the increased xylan amount in polysulfide fibers, but to a lesser extent. Some initial pulp properties like tensile strength, bonding and elasticity are improved.
  • properties of bleached birch kraft pulp can be manipulated in a controlled way by transferring xylan from one pulp onto another. Exploitation of these changes in a pure bleached birch pulp, e.g. better bonding, will be further studied in pulp mixtures expressing certain paper and board grades.
  • Chips from normal pulpwood of birch from southeastern Finland were used in cooking experiments. Over-sized and fine fractions were removed on a wire screen with openings of 16x32 mm and 6x6 mm. From fresh chips of the accept fraction samples of 4.5 kg (as. o.d.) were weighted for the cooks and preserved frozen in a refrigerator. Before cooking the samples were melt at room temperature for a couple of days. Cooking experiments were carried out in KCL's 15 L rotating autoclaves under following conditions: Table 1
  • a polysulfide liquor was prepared at KCL oxidizing a laboratory made white liquor with the Moxy-method. Analysis of liquors before and after the oxidation were as follows:
  • the birch pulps were bleached with the sequence OD(EO)DND to the target brightness 90+ %.
  • Oxygen delignification was carried out in KCL' s 4OL DELFI reactor equipped with indirect oil bath heating and with inverter controlled mixer.
  • the process conditions were as follows:
  • Magnesium sulfate used as an inhibitor was added to pulp in plastic bag before heating the pulp to the reaction temperature by microwave oven.
  • the heated pulp was placed into the reactor, alkali with additional water was charged and the pulp slurry was mixed 30 seconds at a rate of 300 rpm.
  • the reactor was pressurized with oxygen and the pulp slurry was mixed 30 seconds at a rate of 600 rpm. During the whole reaction time the pulp was mixed after every 15 minutes for 18 seconds at a rate of 300 rpm at the balanced reaction temperature.
  • the handsheet was prepared for determination of kappa number, brightness and viscosity (Table 3). Pulp yield and residual alkali in O-stage liquor were determined, too. ECF bleaching
  • the extracted pulp was washed with 2 x 1 L H 2 O + IL 1% acetic acid + 2 x 1 L H 2 O before the yield determination, analysis and testing.
  • a bleached birch sulfate pulp was extracted with alkali under the conditions above but having a pulp charge of 300 g and the alkalinity 1.0 mol/1.
  • the yield of pulp after the extraction was 84.7%.
  • Combined washing waters were acidified to pH 4-5 with cone, acetic acid.
  • the precipitate was separated by centrifuging.
  • the amount of recovered precipitate was 295 g containing 15.0% dry matter with 70.7% xylose.
  • the xylan precipitate was first dissolved in 200 ml IN NaOH (0.01 N NaOH in the two latest experiments 1482 S6 and 1482 S7), then mixed with the pulp slurry containing NaAc 1 mol/1.
  • the alkalinity in the mixture was 0.1 and 0.001 mol NaOH/1, respectively.
  • the mixture was poured into a reactor, where air was removed by nitrogen gas before heating in 30 min to the temperature.
  • the temperature was 120°C, in later experiments 80°C.
  • the pulp was first filtrated, then washed with 2 x 1 L H 2 O + IL 1% acetic acid + 2 x 1 L H 2 O before the yield determination etc.
  • pH in the slurry after the treatment was adjusted, if necessary, to about 7 with acetic acid before the filtration and washings.
  • no acetic acid was used after the treatment or in washing.
  • the bleached pulps were beaten in PFI.
  • the original birch sulfate and polysulfide pulp were beaten with 0, 250, 500 and 1000 revolutions, all other pulps only with 0 and 500 revolutions.
  • the unbeaten and beaten pulps were analyzed for:
  • Xylan removal by the alkali extraction improved drainability of pulp and notably more with the polysulfide pulp than with the kraft pulp.
  • the effect of alkalinity was evident: drainability was improved in spite of xylan sorption. Only in the case of lowered alkalinity drainability as decreased. Water retention values behaved in a similar way to drainability.
  • a high NaOH concentration in the alkali extraction gave a noteworthy increase in bulk of unbeaten kraft pulp.
  • the alkaline extraction increased beating demand and respectively increased density, i.e. decreased bulk of pulp at a certain tensile index.
  • the xylan-rich polysulfide pulp, but not the xylan sorption kraft pulp had higher bulk than the kraft pulp at the same tensile index.
  • Modulus of elasticity after a constant beating of pulp, was reduced by the alkaline extraction of pulp but increased 10 % by the xylan sorption or even more, 30%, by the polysulfide cook.
  • the xylan sorption slightly improved dimensional stability, based on shrinkage of pulp, whereas the effect of the alkali extraction was negative.
  • the polysulfide pulp had 20-25% higher dimensional stability than the kraft pulp.
  • the xylan precipitation dimensional stability of the birch kraft pulp could not be improved to the level of the polysulfide pulp
  • Light scattering coefficient of the sheet with a constant beating was increased by the alkaline extraction of and reduced by the xylan sorption or by polysulfide cook Different beating behaviors of pulps caused, however, that at a constant tensile index level the light scattering coefficients of the kraft, polysulfide and xylan sorption pulps were equal.
  • the alkaline extraction of pulp resulted in lowered light scattering in this comparison.
EP06830916A 2005-12-05 2006-12-05 Method of producing paper and cardboard Withdrawn EP1957709A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI20051256A FI122975B (fi) 2005-12-05 2005-12-05 Menetelmä paperin ja kartongin valmistamiseksi
PCT/FI2006/000406 WO2007065969A1 (en) 2005-12-05 2006-12-05 Method of producing paper and cardboard

Publications (1)

Publication Number Publication Date
EP1957709A1 true EP1957709A1 (en) 2008-08-20

Family

ID=35510626

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06830916A Withdrawn EP1957709A1 (en) 2005-12-05 2006-12-05 Method of producing paper and cardboard

Country Status (5)

Country Link
US (2) US20080295986A1 (fi)
EP (1) EP1957709A1 (fi)
BR (1) BRPI0619442A2 (fi)
FI (1) FI122975B (fi)
WO (1) WO2007065969A1 (fi)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7842161B2 (en) * 2006-12-18 2010-11-30 The University Of Maine System Board Of Trustees Pre-extraction and solvent pulping of lignocellulosic material
US7824521B2 (en) * 2006-12-18 2010-11-02 University Of Maine System Board Of Trustees Process of treating a lignocellulosic material with hemicellulose pre-extraction and hemicellulose adsorption
FI123421B (fi) 2008-05-09 2013-04-30 Upm Kymmene Corp Painettavaksi soveltuva tuote ja menetelmä painettavaksi soveltuvan tuotteen valmistamiseksi
MX2012004407A (es) * 2009-10-16 2012-05-08 Procter & Gamble Estructuras fibrosas que comprenden fibras de pulpa de madera dura tratadas con enzimas.
BR112012014327B1 (pt) * 2009-12-15 2019-06-25 Södra Skogsägarna Ekonomisk Förening Processo de polpação para formar uma mistura de polpa, mistura de polpa, e, polpa comercial
FI20115711L (fi) * 2011-07-01 2013-01-02 Metsae Fibre Oy Menetelmä hemiselluloosien poistamiseksi sellusta
US10415183B2 (en) 2013-04-15 2019-09-17 Metsä Spring Oy Method of producing regenerated cellulose and hemicellulose
CA2965427A1 (en) * 2014-11-17 2016-05-26 Novozymes A/S Enzymatic process combined with hot caustic extraction for the removal of hemicelluloses from paper-grade pulp
CN112048935B (zh) * 2020-08-14 2022-12-06 山鹰纸业(广东)有限公司 生物超声激光打孔纸袋纸及其制备工艺

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL134024C (fi) * 1965-11-17 1900-01-01
GB8406866D0 (en) * 1984-03-16 1984-04-18 British Petroleum Co Plc Separating cellulose and hemicellulose
WO1995000698A1 (en) * 1993-06-25 1995-01-05 Kamyr, Inc. Hemicellulose recovery during kraft pulping
US6605350B1 (en) * 1996-08-23 2003-08-12 Weyerhaeuser Company Sawdust alkaline pulp having low average degree of polymerization values and method of producing the same
US6057438A (en) * 1996-10-11 2000-05-02 Eastman Chemical Company Process for the co-production of dissolving-grade pulp and xylan
AU1871797A (en) * 1997-02-28 1998-09-18 Novo Nordisk A/S Method for producing cellulose derivatives
JP2002510203A (ja) * 1997-06-10 2002-04-02 キシロフィン オイ 製紙等級の硬木パルプからのキシロースの製造方法
FI113060B (fi) * 1999-07-14 2004-02-27 Xyrofin Oy Menetelmä orgaanisten yhdisteiden valmistamiseksi
DE10229818A1 (de) * 2002-06-28 2004-01-15 Carl Zeiss Smt Ag Verfahren zur Fokusdetektion und Abbildungssystem mit Fokusdetektionssystem
PT1883731E (pt) * 2005-05-24 2016-01-26 Int Paper Co Fibras kraft modificadas

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2007065969A1 *

Also Published As

Publication number Publication date
US20080295986A1 (en) 2008-12-04
FI20051256A (fi) 2007-06-06
FI20051256A0 (fi) 2005-12-05
BRPI0619442A2 (pt) 2011-10-04
US20110168345A1 (en) 2011-07-14
FI122975B (fi) 2012-09-28
WO2007065969A1 (en) 2007-06-14

Similar Documents

Publication Publication Date Title
CA2666707C (en) Modified kraft fibers
US20110168345A1 (en) Method of producing paper and cardboard
US8182650B2 (en) Modified Kraft fibers
Odabas et al. Cellulosic fines: Properties and effects
Lindstrom Chemical factors affecting the behaviour of fibres-during papermaking
Pere et al. Influence of the hemicellulose content on the fiber properties, strength, and formability of handsheets
Iakovlev et al. Chemical pulping: paper technical potential of spruce SO2-Ethanol-Water (SEW) pulp compared to kraft pulp
Paszner et al. Beating behaviour and sheet strength development of coniferous organosolv fibers
Guo et al. PULP AND FIBER CHARACTERIZATION OF WHEAT STRAW AND EUCALUPTUS PULPS-A.
Dahlman et al. Effects of surface hardwood xylan on the quality of softwood pulps
Westermark et al. Influence of ray cells on the bleachability and properties of CTMP and kraft pulps
GB2382592A (en) Use of ozone to enhance the wet strength of fibrous cellulosic material
Tschirner et al. Recycling of chemical pulp from wheat straw and corn stover
USRE28777E (en) Refining of vegetable matter and delignification of the refined matter with chlorine dioxide
US20040200589A1 (en) Method of making pulp having high hemicellulose content
US20040200587A1 (en) Cellulose pulp having increased hemicellulose content
EP0096460A2 (en) Process for improving and retaining pulp properties
Laksono et al. Pulp and Paper Properties of Jenitri Wood (Elaeocarpus ganitrus)
Gupta et al. Potential of acetosolv pulping as an environment-friendly pulping method for spruce, beech, miscanthus, and characterization of handsheets
Lamminen Understanding the fines in BCTMP process
Resende et al. HEMICELLULOSES EXTRACTION AND USES IN THE PULP INDUSTRY
Liu et al. The influence of green liquor and anthraquinone-modified kraft pulping on hexenuronic acid and carboxylic acid group contents in high lignin pulps
Alekhina The Impact of Aspen and Alder on the Quality of NHBK
Sanchuan et al. Study on the Pulp and Fiber Characteristics of Wheat Straw and Eucalyptus Pulps

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20080526

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: OY METSAE-BOTNIA AB

Owner name: UPM-KYMMENE CORPORATION

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20130213

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20170301