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WO2007009221A1 - Amelioration de la blancheur et de la stabilite de la blancheur de matieres lignocellulosiques - Google Patents

Amelioration de la blancheur et de la stabilite de la blancheur de matieres lignocellulosiques Download PDF

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Publication number
WO2007009221A1
WO2007009221A1 PCT/CA2006/001146 CA2006001146W WO2007009221A1 WO 2007009221 A1 WO2007009221 A1 WO 2007009221A1 CA 2006001146 W CA2006001146 W CA 2006001146W WO 2007009221 A1 WO2007009221 A1 WO 2007009221A1
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group
groups
paper
paperboard
hydroxymethyl
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PCT/CA2006/001146
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English (en)
Inventor
Zhirun Yuan
Thomas Q. Hu
John A. Schmidt
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Pulp and Paper Research Institute of Canada
FPInnovations
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Pulp and Paper Research Institute of Canada
FPInnovations
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Publication of WO2007009221A1 publication Critical patent/WO2007009221A1/fr
Anticipated expiration legal-status Critical
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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
    • 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
    • D21H21/30—Luminescent or fluorescent substances, e.g. for optical bleaching
    • 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
    • D21H17/03—Non-macromolecular organic compounds
    • D21H17/05—Non-macromolecular organic compounds containing elements other than carbon and hydrogen only
    • D21H17/10—Phosphorus-containing 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
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/63—Inorganic compounds
    • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
    • 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
    • D21H21/28—Colorants ; Pigments or opacifying agents

Definitions

  • the present invention relates to a method that can be used in paper mills to enhance brightness and brightness stability of lignocellulosic materials which have a pigment coating or pigment filler, that contains, or in which the pigment has been treated with, certain water-soluble phosphines or phosphonium compounds.
  • Lignocellulosic materials such as wood are the raw materials used for the production of pulps and papers, hi order to make papers, lignocellulosic materials such as wood are first reduced to pulps (discrete fibres) by a mechanical or chemical pulping process.
  • mechanical pulping pulps are produced in a yield of 90-98% (with retention of lignin) mainly through the action of mechanical forces.
  • chemical pulping pulps are produced through the action of the pulping chemicals such as sodium hydroxide and sodium sulphide at elevated temperatures.
  • mechanical pulps is the so- called thermomechanical pulp (TMP) produced from the thermomechanical pulping process.
  • TMP thermomechanical pulp
  • chemical pulps is the so-called kraft pulp produced from the kraft pulping process.
  • Chemical pulps are often bleached with oxidative bleaching chemicals to remove the residual lignin in the pulps and to provide the bleached pulps with high brightness and brightness stability.
  • Mechanical pulps are bleached, if desired, with chemicals that do not remove lignin significantly or at all, such as hydrogen peroxide or sodium dithionite [Dence and Reeve, Pulp Bleaching - Principles and Practice, Tappi Press: Atlanta, p. 457-512, 1996].
  • Alkaline hydrogen peroxide in the presence of peroxide stabilizers such as sodium silicate and magnesium sulfate, is capable of bleaching mechanical pulps such as spruce TMP from an initial brightness of 55-60% to 70-80% ISO.
  • pigment coating can increase the brightness and brightness stability of lignin-containing and lignin-free papers.
  • the extent of the improvement depends on the coat weight, the pigments used, and the relative brightness of the coating color and the basesheet [Yuan et al., 2004 TAPPI Coating Conference Proceedings, Baltimore, MD, USA].
  • the pigments provide some brightness stability by either scattering or absorbing incident UV light.
  • Common pigments used for the coating of papers include titanium dioxide (TiO 2 ), clay, precipitated calcium carbonate (PCC), and ground calcium carbonate (GCC).
  • the above-mentioned pigments are also commonly used as fillers in various grades of papers to replace more expansive fibers or to obtain improved optical properties and printability.
  • pigment filler improves the paper brightness if the brightness of the filler itself is higher than that of fibers.
  • the application of fillers is especially important when opacity is needed at a low basis weight.
  • THPS tetrakis(hydroxymethyl)phosphonium sulphate
  • P(CH 2 OH) 4 ] 2 SO 4 are acidic (pH -3.2) due to the small dissociation of THPS to THP, formaldehyde and sulfuric acid [Ellzey, Textile Chem. Color. 10(5): 12 (1978); Frank et al., Textile Res. J. 52(11): 678-693 (1982)]. Higher pH will promote the release of formaldehyde from THPS or THP.
  • Formaldehyde an irritant for the respiratory tract, can react with sodium bisulfite to form formaldehyde-bisulfite adduct, or it can be reduced with a reducing agent such as sodium hydrosulfite or sodium borohydride.
  • a reducing agent such as sodium hydrosulfite or sodium borohydride.
  • the present invention provides a method that can be used to produce lignin- containing or lignin-free papers or paperboards with a higher and more stable brightness through a pigment coating or addition of pigment filler, that contains, or in which the pigment has been treated with, certain water-soluble phosphines or phosphonium compounds.
  • the phosphine or phosphonium compounds should possess at least one phosphorus hydroxymethyl bond/linkage. There is a synergy between the said phosphine or phosphonium salt and the pigment on the brightness gain and brightness/light stabilization of papers or paperboards coated or filled with the pigment or filler.
  • This invention also provides the lignin-free or lignin-containing paper or paperboard of higher and more stable brightness, which is produced by this method.
  • the inorganic pigment is the most abundant component in a coating color and it is also the most important factor affecting the properties of the coating color. Two desirable benefits of a pigmented coating or filling are increased brightness and opacity, which result from the high light scattering power of the pigments. Light scattering coefficient is the most important property for pigments.
  • Common inorganic pigments include titanium dioxide (TiO 2 ) clay, precipitated calcium carbonate (PCC), and ground calcium carbonate (GCC), silica and silicate, Talc, and alumina trihydrate.
  • phosphines or phosphonium salts described in WO 2004/070110 Al or a pigmented coating can separately increase the brightness and brightness stability of lignin-containing papers.
  • certain phosphines or phosphonium salts described hereinafter when combined with or used to pretreat pigments, increase synergistically the brightness and brightness stability of lignin-containing or lignin-free, pigment coated or filled papers.
  • THPS tetrakis(hydroxymethyl)phosphonium sulfate
  • a pigmented coating can further improve brightness and brightness stability over the enhancements obtained by using THPS or a pigmented coating alone.
  • a method for the synergistic brightness enhancement and brightness stabilization of papers and paperboards comprising pigmented coatings that contain, or in which the pigment has been treated with a water-soluble phosphine or phosphonium compound of formula (A):
  • the integers y, m, n and z have, in particular, the following values: n is 0 to 2, y is 1 to 5, z is 0 to 2, and m is 0 to 5.
  • synergistic brightness enhancement and brightness stabilization of lignin-containing or lignin-free papers or paperboards can be achieved through a pigment coating or addition of pigment filler, that contains, or in which the pigment has been treated with, certain water-soluble phosphines or phosphonium compounds.
  • the phosphine or phosphonium compounds should possess at least one phosphorus hydroxymethyl bond/linkage, preferably with a water-soluble tertiary phosphine or a quaternary phosphonium compound possessing at least one phosphorus hydroxymethyl bond/linkage.
  • Y 1 and Y 2 are both absent, Ri is a hydroxymethyl (HOCH 2 ) group, R 2 and R 3 , or R 2 , R 3 and R 4 are independently hydrogen, an alkyl group (R) or an ether group
  • R' is either hydrogen or an optionally substituted linear or branched alkyl group or optionally substituted aryl group; wherein optional substitution refers to the presence of one or more substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties;
  • X is suitably selected from chloride, sulfate, hydroxide, hydrosulfite, phosphate, carbonate, bicarbonate, bisulfate, alkoxide, formate, acetate, citrate, oxalate, ascorbate, ethylenediaminetetraacetate or diethylenetriaminepentaacetate.
  • the compounds of formula (A) for use in the invention need to be water-soluble and the variables in formula (A) are selected so that the compounds (A) have an overall water solubility of at least 0.001 g/L.
  • R 1 , R 2 and R 3 groups being collectively selected such that the molecule has an overall solubility of at least 0.001 g/L.
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R 2 and R 3 are independently selected from hydrogen and optionally substituted linear or branch alkyl groups, or optionally substituted aryl groups.
  • optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R' is either hydrogen or an optionally substituted linear or branched alkyl group or optionally substituted aryl group.
  • substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • R 1 is a hydroxymethyl (HOCH 2 ) group, and at least one of R 2 and R 3 is also a CH 2 OH group.
  • the water-soluble phosphine is the commercially available compound, tris(hydroxymethyl)phosphine (THP), P(CH 2 OH) 3 . Diphosphines and Bisphosphines:
  • the R 1 , R 2 , R 3 , R 6 and R 7 groups being collectively selected such that the molecule has an overall solubility of at least 0.001 g/L.
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R 2 , R 3 and R 7 are independently selected from hydrogen, optionally substituted linear or branched alkyl groups, or optionally substituted aryl groups.
  • optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • the diphosphine compound is of C 2 or C s symmetry.
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R' is either hydrogen or an optionally substituted linear or branched alkyl group or optionally substituted aryl group. Where optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R 1 is a hydroxymethyl (HOCH 2 ) group
  • R 2 is the same as R 3
  • R 1 , R 2 , R 3 and R 7 are all hydroxymethyl (CH 2 OH) groups.
  • Ri is a hydroxymethyl group (CH 2 OH); and R 2 , R 3 and R 7 are independently selected from hydrogen, a Lewis acid such as boron trifluoride (BF 3 ), optionally substituted linear or branched alkyl groups, or optionally substituted aryl groups.
  • a Lewis acid such as boron trifluoride (BF 3 )
  • optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • R' is either hydrogen or an optionally substituted linear or branched alkyl group or optionally substituted aryl group. Where optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • the phosphonium compound is the commercially-available tetrakis(hydroxymethyl)phosphonium sulphate (THPS), [P(CH 2 OH) 4 J 2 SO 4 , or tetrakis(hydroxymethyl)phosphonium chloride (THPC), [P(CH 2 OH) 4 ]Cl.
  • THPS tetrakis(hydroxymethyl)phosphonium sulphate
  • THPC tetrakis(hydroxymethyl)phosphonium chloride
  • Rj is a hydroxymethyl group (CH 2 OH); and R 2 , R 3 , R 4 , R 7 and R 8 are independently selected from hydrogen, a Lewis acid such as boron trifluoride (BF 3 ), optionally substituted linear or branched alkyl groups, or optionally substituted aryl groups.
  • a Lewis acid such as boron trifluoride (BF 3 )
  • optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • R 1 is a hydroxymethyl group (CH 2 OH); and R 2 , R 3 , R 4 ,
  • R' is either hydrogen or an optionally substituted linear or branched alkyl group or optionally substituted aryl group. Where optional substitution can refer to the presence of substituents selected from ether, amino, hydroxy, ester, thioether, amide, carbonyl, carboxyl, and carboxylate moieties.
  • Ri is a hydroxymethyl group (CH 2 OH); and at least one OfR 4 , R 7 and R 8 is also a hydroxymethyl (CH 2 OH) group.
  • alkyl and alkyl moieties are straight chain or branched and have 1 to 12, preferably 1 to 6 and more preferably 1 to 4 carbon atoms; alkyl moieties contemplates the alkyl portions of thioether, amide, ether and ester substituents; ii) aryl and aryl moieties and arylene have 6 to 14 carbon atoms and are preferably phenyl or phenylene; aryl moieties contemplates the aryl portions of thioether, amide, ether and ester substituents; iii) water-soluble means, with reference to the compounds of formula (A) that the compounds have an overall water solubility of at least 0.001 g/L.
  • filler refers to mineral pigments used in papermaking or coating processes. THPS can also increase the light scattering powers of the inorganic pigments or fillers even before they are added into the coating
  • Paper or paperboard "treated” with filler and a compound (A) as described herein contemplates the filler and the compound (A) being incorporated in the pulp from which the paper or paperboard is formed, or that the paper or paperboard is coated with a composition of the filler and a compound (A).
  • indications of the filler being present in the paper or paperboard contemplates the filler being incorporated in the pulp from which the paper or paperboard is formed, or that the paper or paperboard is coated with a composition of the filler.
  • the present invention is illustrated but not limited by the following examples.
  • machine-made papers containing mechanical pulp were coated with pigmented formulations with or without THPS or THPP.
  • the basesheet was also treated with water or THPS solution only.
  • the effect of THPS or THPP on brightness and brightness stabilization was studied by incorporating the THPS or THPP as an additive in the coating formulation.
  • the brightness of the coated sheets was then monitored for 20-30 days under two different conditions: storage in the dark at room temperature or exposure to normal office lighting with sunlight passing through a window.
  • ISO brightness was determined according to ISO standard 2470, using a Technidyne Micro TB-IC refiectometer.
  • Example 1 Application of THPS or THPP and/or pigment coating to a 100% BTMP paper
  • the pigmented formulation consisted of 80% ground calcium carbonate (GCC), 20% delaminated clay, starch, latex, and some minor additives.
  • the pH of the coating color was controlled at 8.0.
  • the basesheet was also treated with THPS solution at the same pH.
  • 5 Coating alone increased ISO brightness by 1.4 points compared to the untreated basesheet control, after 30 days of storage in the dark.
  • Treatment with THPS alone increased ISO brightness by 1.5 points.
  • adding THPS to the pigment coating o provided a synergistic brightness increase during dark storage.
  • Including THPS in the pigment coating also provided a synergistic effect in stabilizing the brightness to light exposure.
  • the ISO brightness of the sample treated with coating alone was 2.8 points higher than that of the untreated control after 30 days of light exposure.
  • the ISO brightness of the sample treated with THPS alone was 1.8 5 points higher than that of the control. The sum of these effects is 27% less than the 6.3 points difference in ISO brightness that occurred when THPS was included in the pigment coating.
  • Example 2 Application of THPS and/or pigment coating to a 100% BTMP paper
  • the CLC6000 coater is equipped with an infrared dryer.
  • the coat weight was 8 g/m 2 per side.
  • the pigmented formulation consisted of one pigment at a time, together with some latex and starch as binders.
  • the pH of the coating color was controlled at 7.0.
  • the basesheet was also treated with THPS solution at the same pH.
  • the THPS charge was 0.5% w/w on o.d. fibers.
  • Table 2.1 shows the optical properties and the synergism between THPS and individual pigment.
  • Table 2.1 also shows that the synergistic increase in brightness is due to the increase of light scattering coefficient of the pigment coating, especially for TiO 2 and clay, by THPS.
  • the absorption coefficient of the coated papers did not change with the addition of THPS.
  • Table 2.1 Sheet optical properties anc I the synergism between ' THPS and the pigments
  • ** ⁇ s scattering of sheet with ; i pigment and/or THPS - scattering of base sheet with water.
  • Table 2.2 shows the effect of calendaring with a hot soft-nip calendar to a PPS roughness about 1 ⁇ m on the optical properties of the papers coated with clay, clay and THPS, TiO 2 , and TiO 2 and THPS, respectively.
  • the difference in ISO brightness between the "clay + 0.5% THPS" coated paper and the clay coated paper after calendaring (2.4 ISO points) is larger than that before calendaring (1.3 ISO points).
  • the difference in ISO brightness between the "TiO 2 + 0.5% THPS" coated paper and the TiO 2 coated paper after calendaring (2.3 ISO points) is larger than that before calendaring (1.7 ISO points).
  • Table 2.3 shows the brightness values of various papers before and after 20 days of ambient light exposure.
  • the combination of THPS and the pigment TiO 2 not only provides a synergistic brightness enhancement to the paper, but it also provides more significant, synergistic brightness/light stabilization to the paper.

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Abstract

Cette invention concerne un procédé servant à produire des matières lignocellulosiques, notamment des papiers ou des cartons avec ou sans lignine, avec un degré de blancheur supérieur et plus stable. On obtient cette amélioration de la blancheur et de la stabilité de la blancheur en utilisant des enduits pigmentés qui contiennent également un composé de phosphine ou de phosphonium hydrosoluble comportant au moins une liaison hydroxyméthyle de phosphore. Les pigments peuvent également être pré-traités avec les composés de phosphine ou de phosphonium avant l'adjonction comme charge ou comme préparation de l'enduit couleur. Un exemple de phosphine hydrosoluble est la tris(hydroxyméthyl)phosphine (THP), P(CH2OH)3. Un exemple de composé de phosphonium est le sulfate de tetrakis(hydroxyméthyl)phosphonium (THPS), [P(CH2OH)4]2SO4. Il y a un synergie entre le composé THPS et le pigment, qui agit sur le gain de blancheur et sur la stabilisation de la blancheur/clarté des papiers ou des cartons enduits ou chargées avec ce pigment.
PCT/CA2006/001146 2005-07-15 2006-07-12 Amelioration de la blancheur et de la stabilite de la blancheur de matieres lignocellulosiques Ceased WO2007009221A1 (fr)

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US69938605P 2005-07-15 2005-07-15
US60/699,386 2005-07-15

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3236676A (en) * 1961-06-16 1966-02-22 Albright & Wilson Treatment of cellulose with tetrakis (hydroxymethyl) phosphonium resins
WO2001055506A1 (fr) * 2000-01-28 2001-08-02 M-Real Oyj Procede et composition de revetement pour le revetement d'une bande de papier
US20030089473A1 (en) * 2000-01-22 2003-05-15 Bowdery Ruth Elizabeth Bleaching pulp
WO2004070110A1 (fr) * 2003-02-05 2004-08-19 Pulp And Paper Research Institute Of Canada Procede de blanchiment et de stabilisation du brillant de materiaux lignocellulosiques a l'aide de phosphines hydrosolubles ou de composes de phosphonium
US20050173083A1 (en) * 2004-02-06 2005-08-11 Moyle Bradley E. Optical brightener for aqueous high yield pulp and process for making brightened paper

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3236676A (en) * 1961-06-16 1966-02-22 Albright & Wilson Treatment of cellulose with tetrakis (hydroxymethyl) phosphonium resins
US20030089473A1 (en) * 2000-01-22 2003-05-15 Bowdery Ruth Elizabeth Bleaching pulp
WO2001055506A1 (fr) * 2000-01-28 2001-08-02 M-Real Oyj Procede et composition de revetement pour le revetement d'une bande de papier
WO2004070110A1 (fr) * 2003-02-05 2004-08-19 Pulp And Paper Research Institute Of Canada Procede de blanchiment et de stabilisation du brillant de materiaux lignocellulosiques a l'aide de phosphines hydrosolubles ou de composes de phosphonium
US20050173083A1 (en) * 2004-02-06 2005-08-11 Moyle Bradley E. Optical brightener for aqueous high yield pulp and process for making brightened paper

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DAVIDSON, JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY, vol. 11, no. 4, 1991, pages 419 - 437 *

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