WO1997014847A1 - Acid resistant calcium carbonate filler - Google Patents
Acid resistant calcium carbonate filler Download PDFInfo
- Publication number
- WO1997014847A1 WO1997014847A1 PCT/US1996/016606 US9616606W WO9714847A1 WO 1997014847 A1 WO1997014847 A1 WO 1997014847A1 US 9616606 W US9616606 W US 9616606W WO 9714847 A1 WO9714847 A1 WO 9714847A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- calcium carbonate
- acid
- mixture
- weak acids
- dry weight
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
- C09C3/10—Treatment with macromolecular organic compounds
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
- C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
- C09C1/02—Compounds of alkaline earth metals or magnesium
- C09C1/021—Calcium carbonates
-
- 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
- D21H17/69—Water-insoluble compounds, e.g. fillers, pigments modified, e.g. by association with other compositions prior to incorporation in the pulp or paper
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
- C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
- C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
-
- 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
- D21H17/675—Oxides, hydroxides or carbonates
Definitions
- This invention relates generally to calcium carbonate for use in papermaking, and related industries, and more particularly to a calcium carbonate having acid resistant properties- Titanium dioxide and calcined clay have traditionally been utilized as filler materials in the preparation of neutral to weakly acidic paper in order to improve the optical properties, especially the brightness, of the resultant product. These materials, however, especially titanium dioxide, have the disadvantage of being very expensive, resulting in higher manufacturing costs and an uncompetitively priced paper product .
- Calcium carbonate particularly precipitated calcium carbonate
- Such usage results in a paper with enhanced optical properties, without the expense incurred in using titanium oxide fillers, resulting in a much less expensive product.
- Calcium carbonate cannot generally be used as a filler in acidic paper because it decomposes in an acidic environment. Consequently, there has long been a need to develop a calcium carbonate composition which is acid stabilized and resistant to decomposition at low pH, so that it can be utilized as a filler material in the manufacture of acidic paper, such as groundwood paper, where the use of an alkaline filler would have a negative impact on the final paper properties.
- Paper made from mechanical pulps has been traditionally produced under acidic papermaking conditions because of "fiber alkaline darkening" that occurs as pH rises. This means that there is a reduction in brightness of the paper (brightness reversion) when the pH is raised from acid to alkaline in wood-containing systems.
- Alkaline darkening will occur to some degree in any wood pulps with significant lignin content. The degree of darkening depends on the particular pulps, Ph, and water quality.
- ground calcium carbonate and precipitated calcium carbonate fillers buffer wet end in the 7.5-8.2 pH range. Acid-resistant calcium carbonate compositions thus provide a means for reducing the degree of fiber alkaline darkening and brightness reversion due to their ability to maintain a stabilized pH.
- U. S. Patent 5,043,017 discloses and claims an acid- stable calcium carbonate resistant to degradation in a mildly acidic environment which comprises a mixture of a calcium-chelating agent or a conjugate base, and a weak acid, such that calcium carbonate is coated by, and is in equilibrium with, the calcium-chelating agent or conjugate base and the weak acid.
- Preferred calcium carbonate compositions contain sodium hexametaphosphate and phosphoric acid.
- a still further object of the present invention is to provide a paper having enhanced optical qualities prepared using the calcium carbonate compositions of the present invention.
- the present invention relates to an improved form of calcium carbonate which is stabilized and thus, acid resistant, to enable its use as a filler material in the making of neutral to weakly acid paper, and a process for producing this acid resistant calcium carbonate. More particularly, this invention concerns an acid resistant calcium carbonate consisting essentially of at least about 0.1 percent, based on the dry weight of the calcium carbonate, of a mixture of two or more weak acids, in admixture with the calcium carbonate. It has surprisingly been found that the inclusion of the mixture of two or more weak acids confers a higher degree of stability and acid resistance for calcium carbonate in the presence of fiber slurry, and a longer term of pH stability than the prior art acid-stabilized calcium carbonate compositions. BRIEF DESCRIPTION OF THE DRAWINGS
- FIGURE 1 is a graph comparing the 24 hours ageing of scalenohedral precipitated calcium carbonate compositions of the present invention containing 1, 2 or 6% polyacrylate acid, and various concentrations of phosphoric acid.
- FIGURE 2 is a graph comparing the 24 hours ageing of rhombic precipitated calcium carbonate compositions of the present invention containing 1% or 2% polyacrylate acid, and various concentrations of phosphoric acid.
- FIGURE 3 is a graph comparing the 24 hours ageing of ground precipitated calcium carbonate compositions of the present invention containing 1% or 2% polyacrylate acid, and various concentrations of phosphoric acid.
- FIGURE 4 is a graph showing the pH of a scalenohedral precipitated calcium carbonate composition of the present invention containing 3% polyacrylate acid, and 5% phosphoric acid.
- FIGURE 5 is a graph showing the pH of a scalenohedral precipitated calcium carbonate composition of the present invention containing 1% polymaleic acid, and 4% phosphoric acid.
- FIGURE 6 is a graph showing the pH of a scalenohedral precipitated calcium carbonate composition of the present invention containing 6% polymaleic acid and 1% phosphoric acid.
- the improved form of calcium carbonate prepared by the instant invention is stabilized, and thus, acid resistant, to enable its use as a filler material in the making of neutral to weakly acid paper. While not wishing to be bound by any particular theory as to the operability of the present invention, it is believed that the acid resistance conferred upon the calcium carbonate compositions of the present invention is a result of the inactivation of the surface of the calcium carbonate by the addition of the mixture of the two weak acids.
- the calcium carbonate compositions are rendered acid resistant by the inclusion of at least about 0.1 percent, based on the dry weight of the calcium carbonate, of a mixture of two or more weak acids. Especially preferred as one component of the mixture of weak acids is an organic, polymeric weak acid, such as polyacrylate or polymaleic acid.
- the capability of the acid-stabilized calcium carbonate of the present invention to resist dissociation in an acidic environment is due to the polymer adsorption on the surface of the calcium carbonate, absorption of polymer functional groups on the calcium carbonate surface, and the formation of a buffering system between anionic functional groups of the polymer and a weak acid.
- This mechanism of polymer adsorption is distinct from absorption or reaction of the prior art sodium hexametaphosphate on the surface of calcium carbonate.
- Polymer adsorption can provide a barrier coating on the surface of calcium carbonate which reduces the dissolution reaction of calcium carbonate.
- the weak acids utilized in the compositions of the present invention are preferably weak acids selected from the group consisting of phosphoric acid, metaphosphoric acid, hexa etaphosphoric acid, ethylenediaminetetraacetic acid (EDTA) , citric acid, sulfurous acid, boric acid, acetic acid, weak acids derived from organic polymeric acids, such as polyacrylate acid, polymaleic acid and polycarboxylic acid, and mixtures thereof.
- the mixture of weak acids preferably contains at least one weak acid which is derived from an organic, polymeric acid.
- organic polymeric acids are typically an organic polymer having a weight average molecular weight, M Monsine, in the range of 750-1,000,000, consisting of regularly repeating units or chemically similar units, connected by primary covalent bonds.
- the total amount of the weak acids utilized is at least 0.1 percent, based on the dry weight of the calcium carbonate, and is preferably about 1 to about 8 percent, based on the dry weight of the calcium carbonate.
- a preferred combination of weak acids for use in the present invention is polyacrylate acid with phosphoric acid.
- the calcium carbonate utilized is preferably finely divided and it can be either a precipitated calcium carbonate or a natural ground limestone.
- the process for producing this acid resistant calcium carbonate involves forming a mixture of calcium carbonate with at least about 0.1 percent, based on the dry weight of the calcium carbonate, of the mixture of weak acids. The resultant mixture is blended for a sufficiently long period of time to ensure uniform mixing of the ingredients.
- the calcium carbonate can be utilized in the above- described process either as a dry powder or an aqueous slurry with up to about 60 percent by weight solids content.
- the weak acids can be utilized in the process of preparation in either pure concentrated forms or as aqueous solutions.
- either the polymeric acid or the phosphoric acid can be first added, followed by the addition of the second acid.
- the polymeric acid and phosphoric acid can be added at the same time, or the polymeric acid and phosphoric acid can be mixed together and then added to the calcium carbonate.
- composition of the present invention can be utilized to.improve the optical properties of neutral to weakly acidic paper by its addition to the paper during standard manufacturing processes.
- the calcium carbonate composition of the present invention is added to a first paper furnish containing components necessary for making acidic paper to thereby form a second paper furnish.
- Acid stabilized scalenohedral precipitated calcium carbonate slurry can be obtained by the addition of a polymeric acid such as polyacrylate acid, and a weak acid such as phosphoric acid. Initially, 1%, 3%, and 6% polyacrylate acid, based on the dry weight of calcium carbonate, was added into a 19.7% solids slurry of scalenohedral precipitated calcium carbonate. The pH of the untreated scalenohedral precipitated calcium carbonate slurry was 9.05. After mixing, 1-6% phosphoric acid, based on the dry weight of calcium carbonate, was added. A plot of the pH was measured for each sample after 24-hours ageing as shown in Figure 1.
- a long-term low pH stabilized scalenohedral precipitated calcium carbonate slurry can be obtained by the combination of polyacrylate acid and phosphoric acid.
- the initial pH of scalenohedral precipitated calcium carbonate slurry was 9.05.
- 3% polyacrylate acid, based on the dry weight of calcium carbonate was added to 19.8% solids scalenohedral precipitated calcium carbonate slurry, followed by the addition of 5% phosphoric acid, based on the dry weight of calcium carbonates, as shown in Figure 4.
- the pH of scalenohedral precipitated calcium carbonate slurry were measured and found to be 6.32 after two weeks ageing.
- Acid stabilized scalenohedral precipitated calcium carbonate slurry can be obtained by the addition of a polymeric acid such as polymaleic acid, and a weak acid such as phosphoric acid. Initially, 1% polymaleic acid, based on the dry weight of calcium carbonate, was added into 19.7% solids slurry of scalenohedral precipitated calcium carbonate. The pH of untreated scalenohedral precipitated calcium carbonate slurry was 9.05. After mixing, 4% phosphoric acid, based on the dry weight of calcium carbonate, was added. A plot of the pH was measured after 47 hours ageing as shown in Figure 5. The initial pH of the slurry was measured and found to be 5.38, which rose to 6.80 after 47 hours ageing. EXAMPLE 6 Scalenohedral Precipitated Calcium Carbonate
- Acid stabilized scalenohedral precipitated calcium carbonate slurry can be obtained by the addition of a polymeric acid such as polymeric acid, and a weak acid such as phosphoric acid. Initially, 6% polymaleic acid, based on the dry weight of calcium carbonate, was added into 19.7% solids slurry of scalenohedral precipitated calcium carbonate. The pH of untreated scalenohedral precipitated calcium carbonate slurry was 9.05. After mixing, 1% phosphoric acid, based on the dry weight of calcium carbonate, was added. A plot of the pH was measured after 118 hours ageing as shown in Figure 6. The initial .pH of the slurry was measured and found to be 5.70. After 118 hours ageing, the pH was again measured and found to be 6.46.
- a polymeric acid such as polymeric acid
- a weak acid such as phosphoric acid
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
- Paper (AREA)
- Pigments, Carbon Blacks, Or Wood Stains (AREA)
- Dental Preparations (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9515975A JPH11514325A (en) | 1995-10-20 | 1996-10-18 | Acid resistant calcium carbonate filler |
EP96936596A EP0859885A4 (en) | 1995-10-20 | 1996-10-18 | Acid resistant calcium carbonate filler |
AU74484/96A AU712682B2 (en) | 1995-10-20 | 1996-10-18 | Acid resistant calcium carbonate filler |
CA 2235013 CA2235013A1 (en) | 1995-10-20 | 1996-10-18 | Acid resistant carbonate composition containing mixtures of weak acids and uses therefor |
BR9610864A BR9610864A (en) | 1995-10-20 | 1996-10-18 | Resistant calcium carbonate and acid processes to prepare the same and to improve the optical properties of neutral to weakly acidic paper by the addition of a calcium carbonate composition |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US54614595A | 1995-10-20 | 1995-10-20 | |
US08/546,145 | 1995-10-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997014847A1 true WO1997014847A1 (en) | 1997-04-24 |
Family
ID=24179073
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1996/016606 WO1997014847A1 (en) | 1995-10-20 | 1996-10-18 | Acid resistant calcium carbonate filler |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0859885A4 (en) |
JP (1) | JPH11514325A (en) |
AR (1) | AR008038A1 (en) |
AU (1) | AU712682B2 (en) |
BR (1) | BR9610864A (en) |
WO (1) | WO1997014847A1 (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2871474A1 (en) * | 2004-06-11 | 2005-12-16 | Omya Development Ag | NEW DRY MINERAL PIGMENT CONTAINING CALCIUM CARBONATE, AQUEOUS SUSPENSION CONTAINING IT AND USES THEREOF |
EP2679638A1 (en) | 2012-06-28 | 2014-01-01 | Omya International AG | High solids aqueous mineral and/or filler and/or pigment suspension in acidic pH environment |
EP2195109B1 (en) * | 2007-09-28 | 2015-12-09 | Coatex S.A.S. | Use of phosphoric acid for reducing the amount of free dispersant in a method for concentrating calcium carbonate in water |
EP3020769A1 (en) | 1998-12-24 | 2016-05-18 | Omya International AG | Novel treated mineral, filler or pigment for paper, in particular a pigment containing natural caco3, method for manufacturing same, compositions containing same, and uses thereof |
EP3245257B1 (en) | 2015-01-15 | 2019-11-13 | Omya International AG | Surface-treated calcium carbonate with improved stability in environments with a ph of 4.5 to 7 |
RU2738378C2 (en) * | 2016-09-08 | 2020-12-11 | Шефер Кальк Гмбх Унд Ко. Кг | Calcium carbonate additive |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2004087574A1 (en) * | 2003-03-31 | 2006-06-29 | サンノプコ株式会社 | Dispersant for heavy calcium carbonate wet grinding process |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4240870A (en) * | 1978-09-13 | 1980-12-23 | Shiraishi Kogyo Kaisha, Ltd. | Filled paper |
US5156719A (en) * | 1990-03-09 | 1992-10-20 | Pfizer Inc. | Acid-stabilized calcium carbonate, process for its production and method for its use in the manufacture of acidic paper |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4244933A (en) * | 1978-04-05 | 1981-01-13 | Shiraishi Kogyo Kaisha, Ltd. | Calcium carbonate particles and processes for preparing same |
FR2642415B1 (en) * | 1989-01-27 | 1991-04-05 | Coatex Sa | PROCESS FOR GRINDING CALCIUM CARBONATE IN AQUEOUS MEDIA |
JP3254021B2 (en) * | 1992-12-14 | 2002-02-04 | 三菱化学株式会社 | Polyolefin resin composition with improved hue |
-
1996
- 1996-10-18 EP EP96936596A patent/EP0859885A4/en not_active Ceased
- 1996-10-18 BR BR9610864A patent/BR9610864A/en not_active Application Discontinuation
- 1996-10-18 JP JP9515975A patent/JPH11514325A/en active Pending
- 1996-10-18 AU AU74484/96A patent/AU712682B2/en not_active Ceased
- 1996-10-18 WO PCT/US1996/016606 patent/WO1997014847A1/en not_active Application Discontinuation
- 1996-10-21 AR ARP960104836A patent/AR008038A1/en unknown
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4240870A (en) * | 1978-09-13 | 1980-12-23 | Shiraishi Kogyo Kaisha, Ltd. | Filled paper |
US5156719A (en) * | 1990-03-09 | 1992-10-20 | Pfizer Inc. | Acid-stabilized calcium carbonate, process for its production and method for its use in the manufacture of acidic paper |
Non-Patent Citations (1)
Title |
---|
See also references of EP0859885A4 * |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP3020769A1 (en) | 1998-12-24 | 2016-05-18 | Omya International AG | Novel treated mineral, filler or pigment for paper, in particular a pigment containing natural caco3, method for manufacturing same, compositions containing same, and uses thereof |
EA010929B1 (en) * | 2004-06-11 | 2008-12-30 | Омиа Девелопмент Аг | Mineral pigment |
WO2005121257A3 (en) * | 2004-06-11 | 2006-04-27 | Omya Development Ag | Novel dry mineral pigment containing calcium carbonate, aqueous suspension containing said pigment, and the uses thereof |
FR2871474A1 (en) * | 2004-06-11 | 2005-12-16 | Omya Development Ag | NEW DRY MINERAL PIGMENT CONTAINING CALCIUM CARBONATE, AQUEOUS SUSPENSION CONTAINING IT AND USES THEREOF |
KR101185660B1 (en) | 2004-06-11 | 2012-09-24 | 옴야 디벨로프먼트 아게 | Novel dry mineral pigment containing calcium carbonate, aqueous suspension containing said pigment, and the uses thereof |
WO2005121257A2 (en) * | 2004-06-11 | 2005-12-22 | Omya Development Ag | Novel dry mineral pigment containing calcium carbonate, aqueous suspension containing said pigment, and the uses thereof |
US10308813B2 (en) | 2004-06-11 | 2019-06-04 | Omya International Ag | Dry mineral pigment containing calcium carbonate, aqueous suspension containing said pigment, and the uses thereof |
US10876005B2 (en) | 2004-06-11 | 2020-12-29 | Omya International Ag | Dry mineral pigment containing calcium carbonate, aqueous suspension containing said pigment, and the uses thereof |
EP2195109B1 (en) * | 2007-09-28 | 2015-12-09 | Coatex S.A.S. | Use of phosphoric acid for reducing the amount of free dispersant in a method for concentrating calcium carbonate in water |
EP2679638A1 (en) | 2012-06-28 | 2014-01-01 | Omya International AG | High solids aqueous mineral and/or filler and/or pigment suspension in acidic pH environment |
WO2014001063A1 (en) | 2012-06-28 | 2014-01-03 | Omya International Ag | High solids aqueous mineral and/or filler and/or pigment suspension in acidic ph environment |
US9328222B2 (en) | 2012-06-28 | 2016-05-03 | Omya International Ag | High solids aqueous mineral and/or filler and/or pigment suspension in acidic pH environment |
EP3245257B1 (en) | 2015-01-15 | 2019-11-13 | Omya International AG | Surface-treated calcium carbonate with improved stability in environments with a ph of 4.5 to 7 |
RU2738378C2 (en) * | 2016-09-08 | 2020-12-11 | Шефер Кальк Гмбх Унд Ко. Кг | Calcium carbonate additive |
Also Published As
Publication number | Publication date |
---|---|
EP0859885A1 (en) | 1998-08-26 |
JPH11514325A (en) | 1999-12-07 |
BR9610864A (en) | 1999-04-06 |
AU712682B2 (en) | 1999-11-11 |
EP0859885A4 (en) | 1999-06-09 |
AR008038A1 (en) | 1999-12-09 |
AU7448496A (en) | 1997-05-07 |
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