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EP0419206B1 - Granules cellulaires de polymères et papier ainsi fabriqué - Google Patents

Granules cellulaires de polymères et papier ainsi fabriqué Download PDF

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Publication number
EP0419206B1
EP0419206B1 EP90310187A EP90310187A EP0419206B1 EP 0419206 B1 EP0419206 B1 EP 0419206B1 EP 90310187 A EP90310187 A EP 90310187A EP 90310187 A EP90310187 A EP 90310187A EP 0419206 B1 EP0419206 B1 EP 0419206B1
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EP
European Patent Office
Prior art keywords
paper
granules
calcium carbonate
weight
vesiculated
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.)
Expired - Lifetime
Application number
EP90310187A
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German (de)
English (en)
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EP0419206A1 (fr
Inventor
Loreen Doris Ferguson
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.)
PPG Architectural Coatings Canada Inc
Original Assignee
ICI Canada Inc
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Filing date
Publication date
Application filed by ICI Canada Inc filed Critical ICI Canada Inc
Publication of EP0419206A1 publication Critical patent/EP0419206A1/fr
Application granted granted Critical
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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
    • 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
    • D21H17/33—Synthetic macromolecular compounds
    • D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
    • D21H17/53—Polyethers; Polyesters
    • 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
    • D21H21/50—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 form
    • D21H21/52—Additives of definite length or shape
    • D21H21/54—Additives of definite length or shape being spherical, e.g. microcapsules, beads

Definitions

  • This invention relates to vesiculated polymer granules and more particularly, to paper comprising said granules.
  • Paper is typically manufactured by transferring a suspension (or furnish) of fibrous material, sizing materials, wet and dry strength additives, defoamers, biocides, dyes, pigments, retention aids and/or fillers, to a forming wire for water drainage to concentrate solids.
  • the paper formed on the wire is subsequently dried to a desired basis weight (weight per unit area).
  • the fibrous material used in papermaking is cellulosic or non-cellulosic in form, e.g. plant matter, such as trees, cotton, bagasse, and synthetic polymers, such as rayon, which may have been delignified and/or bleached.
  • fillers are normally added during paper production in order to replace a portion of the expensive pulp fibres with less expensive material.
  • the fillers of choice for alkaline paper which in this specification means any paper produced from an aqueous fibrous suspension of pH 7 or greater, are usually selected from the class of mineral fillers known as clays, such as kaolin, and calcium carbonates.
  • the calcium carbonates of use as paper making fillers fall under three classifications, namely, ground, chalk and precipitated carbonates.
  • Ground calcium carbonates occur naturally in the earth and are mined and milled to a desired particle size.
  • the chalk form of calcium carbonate is the skeletal remains of marine organisms, while the precipitated calcium carbonate is a man-made form of calcium carbonate prepared by bubbling carbon dioxide gas through an aqueous slurry of calcium hydroxide, followed by precipitation of the calcium carbonate produced.
  • Calcium carbonate is not used in acidic paper making because calcium carbonate would cause foaming in the acidic aqueous paper composition due to the production of carbon dioxide.
  • Fillers are also generally used to impart suitable optical properties, namely, whiteness, brightness, opacity, and colour, and surface properties, such as, smoothness and printability.
  • the degree of opacity of a particular substrate is the result of diffuse light-scattering which occurs when visible radiation is reflected from particles on the surface of the substrate and the substrate medium itself.
  • inorganic mineral fillers mentioned hereinabove, and in particular calcium carbonate it is customary to use the inorganic mineral fillers mentioned hereinabove, and in particular calcium carbonate, to enhance the optical and surface properties of paper sheets.
  • inorganic mineral filler which can be added to the paper.
  • inorganic mineral filler content increases, there is a substantial loss of the physical strength properties of the paper. This loss of physical properties results because of interference with the hydrogen bonding between the strands of fibrous material, by the filler, and because with increased inorganic mineral filler content there is less fiber present in the paper sheet to contribute to the strength.
  • vesiculated granules of carboxylated unsaturated polyester crosslinked with ethylenically unsaturated monomer can confer advantageous properties, such as improved opacity to paper and coating compositions in which they are incorporated.
  • the background to the use of vesiculated granules in papermaking is well covered in the literature, for example, in articles by Kershaw (Australian OCCA Proceedings and News, August 1971), and Treier (TAPPI, Vol. 55, No. 5, 1972).
  • pigment may be dispersed in either or both of the first emulsion components using conventional pigment dispersants and defoamers.
  • the technique of preparing vesiculated materials is discussed in detail in EP-A-0,307,139 (equivalent to US-A-4,808,633, assigned to CIL Inc.) wherein the use of a specific alkyl acryloyl derivative-containing polymeric vesiculated granule, for making paper is described.
  • the granule is added to provide improved retention of fines and for increased opacity.
  • No reference is made to improved physical properties, or to the use of the high levels of calcium carbonate contemplated in the present invention.
  • EP-A-0,204,916 and EP-A-0,268,729 describe methods for producing high bulk calendered paper containing vesiculated beads.
  • EP-A-0,204,916 describes a high bulk calendered paper wherein the opacity of the paper is increased by the addition of vesiculated granules in the amount of 0.5 to 15%, and preferably 2 to 10%, by weight of the paper produced. Papers produced according to EP-A-0,204,916 have increased thickness and resistance to print show through, while the brightness and opacity of the paper is maintained. This allows the amount of titanium dioxide pigment to be reduced, which lowers the cost of the resulting paper.
  • EP-A-0,268,729 describes a similar paper as in EP-A-0,204,916 with increased thickness and resistance to print show through while maintaining brightness and opacity, wherein the polymeric vesiculated granule concentration is between 2 and 6%, and preferably 4 and 6%, of the total paper weight.
  • a neutralized polycarboxylic acid polymer thickener is added to reduce the proportion of fines which pass through the paper forming wire.
  • EP-A-0,268,729 and EP-A-0,204,916 describe paper compositions prepared from acidic furnishes.
  • the aqueous furnish has a pH of from 4 to 6.
  • Both patent applications also state that physical properties are maintained by the replacement of titanium dioxide with polymeric vesiculated granules.
  • both patents are silent on the use of polymeric vesiculated granules in an alkaline paper composition, and in particular, paper compositions which comprise calcium carbonate filler.
  • the improvement, according to the present invention, that has been observed in the physical properties of alkaline paper, allows the paper maker to lower the cost of the paper produced by either adding additional calcium carbonate and, thus, replacing additional expensive fibrous material while maintaining constant physical properties; or by increasing the line speed of the paper machine, because of the improved physical properties of the paper, and thus producing additional paper per unit time.
  • the present invention provides an alkaline paper as hereinbefore defined, comprising a fibrous cellulosic material; 1.0 to 10.0%, by weight of the paper, of polymeric vesiculated granules; and 5 to 35% by weight of paper, of calcium carbonate filler.
  • the invention provides an alkaline paper as hereinbefore defined wherein said alkaline paper comprises 1 to 5% of said polymeric vesiculated granules.
  • the invention provides an alkaline paper as hereinabove defined wherein said calcium carbonate level is between 10 and 25% by weight of paper.
  • precipitated or ground calcium carbonates are preferred, with precipitated calcium carbonate being the most preferred.
  • fillers in addition to calcium carbonate, other fillers, pigments, extenders and/or opacifiers such as titanium dioxide, clay and talc may be added to the paper suspension in accordance with the papermaking prior art or may be added to the vesiculated granule during production of the granule.
  • opacifiers such as titanium dioxide, clay and talc
  • vesiculated polymer granules By vesiculated polymer granules is meant granules of polymer, preferably spheroidal granules, which have a cell-like structure, the walls of which are provided by the polymer.
  • the granules comprise a plurality of cells or vesicles (that is they are not mono-cellular or balloon-like) and although the vesicles are not necessarily of uniform size, the ratio of the diameter of the granule to the mean individual vesicle diameter is generally at least 5:1.
  • the vesicles typically occupy from 5 to 95% of the total volume of the granules and the maximum diameter of the vesicles is 20 ⁇ m.
  • Low vesicle volumes are usually associated with granules of high mechanical strength which are particularly useful for some applications, but to achieve the most useful opacifying effects the vesicles typically occupy at least 20% of the total volume of the granules, preferably 20-75% of the volume.
  • the invention provides an alkaline paper as described hereinabove wherein said granules have a mean diameter of 1 to 100 ⁇ m, the ratio of the granule to the mean vesicle diameter is at least 5:1, the maximum diameter of the vesicles is 20 ⁇ m, and volume of the vesicles is from 5 to 95% of the volume of the granule.
  • the granules have substantially continous, solid walls and have a preselected and targeted particle size. Broadly, the granules may have a mean diameter of 1 to 100 ⁇ m. In general we find that granules having a mean diameter of 1 to 50 ⁇ m are of the most value as opacifying agents.
  • polyelectrolyte retention aids it is customary to incorporate in the dilute paper furnish, immediately prior to formation on the wire, small amounts of polyelectrolyte retention aids to give improved retention of the inorganic mineral fillers and any fine fractions of the cellulosic materials on the wire during sheet formation.
  • a cationic retention aid is used to prepare or "condition" the furnish prior to the addition of an anionic retention aid.
  • the dual retention aid system is usually comprised of polymeric polyelectrolytes, e.g. polyacrylamides and polyethyleneimines.
  • a further aspect of the present invention is the alkaline aqueous compositions, which in this specification means any a composition of pH 7 or greater used, in the preparation of the papers of the present invention, described hereinabove.
  • the invention further provides an alkaline aqueous composition
  • a fibrous material 1.0 to 10% of polymeric vesiculated granules, and 5 to 35% of calcium carbonate filler wherein the percentages expressed are as percentages by weight of the resultant paper produced from said composition.
  • the aqueous slurry of vesiculated polyester granules that is formed according to the technique described in U.S. Patent No. 4,808,633 may be used directly in paper wet-end applications.
  • the aqueous slurry of vesiculated polyester granules may also be dewatered, by any convenient means, for example by the method described in United States Patent No. 4,154,923 and subsequently redispersed in an aqueous or non-aqueous medium, before being incorporated into the paper furnish.
  • the pulp component of the alkaline paper to be produced can be formed in part or totally from hardwood, softwood and recycled pulps and/or broke if desired, incorporating an internal sizing agent, for example, alkyl ketene dimer emulsion, or alkyl succinic anhydride.
  • an internal sizing agent for example, alkyl ketene dimer emulsion, or alkyl succinic anhydride.
  • the upper limit of usefulness for the vesiculated polymeric granules be 10 weight percent of the total paper solids. Because of the cost of the polymeric vesiculated granules and because of a diminishing improvement in physical properties at higher levels of granules, it is preferred that the level of granules be less than 5 weight percent and even more preferably less than 3 weight percent.
  • Pigmented vesiculated polyester resin granules having a 10 ⁇ m (95 percentile) diameter maximum, 5.2 ⁇ m mean average diameter of use in the practice of the present invention were prepared according to the technique of Example 1 of U.S.-A-4,808,633 but with the following formulation.
  • Table A outlines some of the physical parameters of the granules obtained.
  • TABLE A Property 10 ⁇ m Pigmented Vesiculated Granules Density of dried granules 0.59 g/ml % vesiculation (1) 65% Weight solids 21.2% Volume solids 36% Maximum granule size (2) 12 ⁇ m Median granule size 5.2 ⁇ m Minimum granule size 3 ⁇ m Vesicle pore size (3) 0.5-3.0 ⁇ m Surface pores on granule ⁇ 0.2 ⁇ m Thickness of granule wall 0.1-0.5 ⁇ m Note: (1) vesiculation determined by mercury porisimetry (2) granule size determined by Laser Diffraction Granulometer (3) internal diameters measured using Scanning Electron Microscopy
  • Freeness of pulp is a measure of the drainage rate of water through the pulp and is measured in accordance with the TAPPI (Technical Association of Pulp and Paper Industry) Standard T 227 om-75 and is referred to as Canadian Standard Freeness, measured in millilitres;
  • Opacity of the paper sheet is expressed as a contrast ratio opacity (C/R Opacity) and measured in accordance with TAPPI Standard T 425 om-81 using light with a wavelength of 572 nanometers;
  • the term handsheet is used to refer to a paper sheet made in accordance with and employing the equipment described in the TAPPI standard T 205 om-81; and Conditioning refers to the conditioning atmosphere of 23.0°C +/- 1°C, and 50.0% +/- 2.0% relative humidity that the paper sheets are exposed to in accordance with TAPPI standards T 405 om-83.
  • Handsheets as discussed hereinbelow in Example 2 were prepared by the following general procedure.
  • the solids in the final pulp slurrys were comprised of fully bleached kraft hardwood or softwood pulps that had been soaked in water for four hours and were refined to a Canadian Standard Freeness(CSF) of 400 or 600mls. After refining, the pulps were mixed together and then divided into individual samples of pulp calculated to give a target basis weight when combined with the fillers.
  • the pulp samples were dispersed in water, and cationic polymeric retention aid was added.
  • the pH of the furnish was controlled to 7.8 to 8.2 by the addition of dilute sodium hydroxide as required.
  • the furnish was subsequently passed through a sheetmaker and the resultant handsheet pressed and conditioned.
  • the hereinabove general procedure for the preparation of handsheets was carried out to prepare a number of different samples for testing of physical properties.
  • the furnish comprised a fully bleached kraft hardwood/softwood (50/50) pulp blend and filler or filler blends comprising polymeric vesiculated granules (PVG), precipitated calcium carbonate (PCC), and/or titanium dioxide (TiO2).
  • PVG polymeric vesiculated granules
  • PCC precipitated calcium carbonate
  • TiO2 titanium dioxide
  • the hardwood pulp had a CSF of 400mls and the softwood had a CSF of 600mls.
  • the PCC has an average particle size of 1.2 ⁇ m and has a scalenohedral crystal form.
  • the retention aids were commercially available cationic and anionic polyacrylamides.
  • the physical properties of the various handsheets were tested according to the following TAPPI standard test methods for paper: T220 OM-88 Physical Testing of pulp handsheets T
  • handsheet number 16 which contains no pigment, filler or polymeric vesiculated granules and constitutes the fibrous material only, demonstrates superior physical properties to the other handsheets prepared. However, this handsheet would have the highest cost of all of the handsheets since it comprises pulp fibre only and, has the lowest C/R opacity.
  • handsheets 1 to 15 which handsheets comprise calcium carbonate, titanium dioxide and/or polymeric vesiculated granules, are approximately equal, with opacity generally increasing as total filler level increases.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Paper (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
  • Multicomponent Fibers (AREA)

Claims (9)

  1. Papier alcalin comprenant une matière cellulosique fibreuse; 1,0 à 10,0% en poids du papier, de granules polymères vésiculés; et 5 à 35% en poids du papier, de charge en carbonate de calcium.
  2. Papier selon la revendication 1 caractérisé en ce que lesdits granules ont un diamètre moyen de 1 à 100 microns, le rapport entre le granule et le diamètre moyen de vésicule est d'au moins 5:1, le diamètre maximal des vésicules est de 20 microns, et le volume des vésicules est de 5 à 95% du volume des granules.
  3. Papier selon la revendication 2 caractérisé en ce que lesdits granules ont un diamètre moyen de 1 à 50 microns.
  4. Papier selon la revendication 1 comprenant 1,0 à 5,0% en poids desdits granules.
  5. Papier selon la revendication 1 comprenant 10 à 25% en poids de carbonate de calcium.
  6. Papier selon une des revendications 1, 2 ou 3, caractérisé en ce que ledit carbonate de calcium est sous forme de précipité.
  7. Papier selon une des revendications 1, 2 ou 3, comprenant en outre une aide à la rétention.
  8. Papier selon une des revendications 1, 2 ou 3 comprenant en outre d'autres charges ou pigments conventionnels dans la fabrication du papier.
  9. Méthode pour améliorer les propriétés physiques d'un papier alcalin comprenant :
    (i) la préparation d'un mélange aqueux d'une matière cellulosique fibreuse; 5 à 35% en poids de matière solide cellulosique, d'une charge en carbonate de calcium; et 1 à 10%, en poids de matière solide cellulosique, de granules polymères vésiculés; et
    (ii) l'élimination de l'eau dudit mélange, pour constituer un papier alcalin.
EP90310187A 1989-09-21 1990-09-18 Granules cellulaires de polymères et papier ainsi fabriqué Expired - Lifetime EP0419206B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US41046689A 1989-09-21 1989-09-21
US410466 1989-09-21
CA000614385A CA1335688C (fr) 1989-09-21 1989-09-28 Granules de polymeres vesicules et papier fait a partir de ceux-ci

Publications (2)

Publication Number Publication Date
EP0419206A1 EP0419206A1 (fr) 1991-03-27
EP0419206B1 true EP0419206B1 (fr) 1994-08-31

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Application Number Title Priority Date Filing Date
EP90310187A Expired - Lifetime EP0419206B1 (fr) 1989-09-21 1990-09-18 Granules cellulaires de polymères et papier ainsi fabriqué

Country Status (6)

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EP (1) EP0419206B1 (fr)
JP (1) JPH03130497A (fr)
AT (1) ATE110811T1 (fr)
AU (1) AU635330B2 (fr)
CA (1) CA1335688C (fr)
DE (1) DE69012028T2 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1602783B1 (fr) * 2004-04-23 2014-02-26 Rohm And Haas Company Procédé de fabrication de papier
US20050236125A1 (en) * 2004-04-23 2005-10-27 Brown James T Method of preparing paper
ES2351869T3 (es) * 2004-04-23 2011-02-11 Rohm And Haas Company Procedimiento para preparar un material laminado decorativo.

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3779055D1 (de) * 1986-11-10 1992-06-17 Rohm & Haas Herstellung von blaeschengefuellte perlen enthaltendes, hochbauschiges kalandriertes papier.
GB2201171B (en) * 1987-02-14 1991-01-02 Laporte Industries Ltd Compositions for use in the treatment of cellulosic materials and their preparation
US4808633A (en) * 1987-09-08 1989-02-28 C-I-L Inc. Vesiculated polymer granules

Also Published As

Publication number Publication date
DE69012028T2 (de) 1994-12-22
DE69012028D1 (de) 1994-10-06
JPH03130497A (ja) 1991-06-04
AU6309090A (en) 1991-03-28
AU635330B2 (en) 1993-03-18
EP0419206A1 (fr) 1991-03-27
CA1335688C (fr) 1995-05-30
ATE110811T1 (de) 1994-09-15

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