Novel inorganic pigment containing calcium carbonate, aqueous suspension containing same, and uses thereof

• US 20060162884A1
• Filed: 03/17/2004
• Published: 07/27/2006
• Est. Priority Date: 03/18/2003
• Status: Active Grant

• Current Assignee: Omya International AG
• Original Assignee: Omya International AG
• Inventors: Buri, Matthias, Blum, Rene Vinzenz, Gane, Patrick
• Granted Patent: US 9,644,101 B2
• Time in Patent Office: Days
• US Class Current: 162/158
• CPC Class Codes: B41M 5/0023 Digital printing methods characterised by the inks used inks per se C09D11/00
• CPC Class Codes: B41M 5/5218 characterised by inorganic additives, e.g. pigments, clays
• CPC Class Codes: C01P 2004/03 obtained by SEM
• CPC Class Codes: C01P 2004/61 Micrometer sized, i.e. from 1-100 micrometer
• CPC Class Codes: C01P 2004/62 Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2006/12 Surface area
• CPC Class Codes: C01P 2006/60 Optical properties, e.g. expressed in CIELAB-values
• CPC Class Codes: C09C 1/021 Calcium carbonates
• CPC Class Codes: C09C 1/022 Treatment with inorganic compounds
• CPC Class Codes: D21H 17/675 Oxides, hydroxides or carbonates
• CPC Class Codes: D21H 19/385 Oxides, hydroxides or carbonates

Abstract

The present invention concerns the technical sector of mineral pigments containing a product formed in situ by the double and/or multiple reaction between a calcium carbonate and the reaction product or products of the said carbonate with one or more moderately strong to strong H₃O⁺ ion donors and the reaction product or products of the said carbonate with gaseous CO₂ formed in situ and/or coming from an external supply, and at least one aluminium silicate and/or at least one synthetic silica and/or at least one calcium silicate and/or at least one silicate of a monovalent salt such as sodium silicate and/or potassium silicate and/or lithium silicate, and/or at least one aluminium hydroxide and/or at least one sodium and/or potassium aluminate, containing less than 0.1% by weight silicate of a monovalent salt such as sodium, potassium or lithium silicate or mixtures thereof, relative to the dry weight of calcium carbonate, having a pH greater than 7.5 measured at 20° C., and their uses in papermaking applications such as mass filling and/or the coating of paper and more particularly of printing paper, in particular for offset printing, or digital printing such as inkjet and/or laser printing.

Claims

1. A mineral pigment containing calcium carbonate characterized in that it contains a product formed in situ by the double and/or multiple reaction between a calcium carbonate and the reaction product or products of the said carbonate with gaseous CO₂ formed in situ and/or coming from an external supply, and the reaction product or products of the said carbonate with one or more moderately strong to strong H₃O⁺ ion donors and at least one aluminium silicate and/or at least one synthetic silica and/or at least one calcium silicate and/or at least one silicate of a monovalent salt such as sodium silicate and/or potassium silicate and/or lithium silicate, preferably such as sodium silicate and/or at least one aluminium hydroxide and/or at least one sodium and/or potassium aluminate, and in that it contains less than 0.1% by weight silicate of a monovalent salt such as sodium, potassium or lithium silicate or mixtures thereof, preferably such as sodium silicate, relative to the dry weight of the calcium carbonate, and characterized in that it has a pH greater than 7.5 measured at 20°

C.

2. A mineral pigment according to claim 1, characterized in that the calcium carbonate is a natural calcium carbonate or a mixture of natural calcium carbonate with talc, kaolin, titanium dioxide, magnesium oxide or any mineral inert vis-à

-vis moderately strong to strong H₃O⁺ ion donors.

3. A mineral pigment according to claim 2, characterized in that the natural calcium carbonate is chosen from amongst a marble, a calcite, a chalk, a dolomite or mixtures thereof.

4. A mineral pigment according to claim 1, characterized in that the moderately strong to strong H₃O⁺ ion donors are chosen from amongst the moderately strong to strong acids or mixtures thereof generating H₃O⁺ ions.

5. A mineral pigment according to claims 1, characterized in that the strong acids are preferentially chosen from amongst acids having a pK_a of less than or equal to zero at 22°

C. and more particularly chosen from amongst sulphuric acid, hydrochloric acid or mixtures thereof and characterized in that the moderately strong H₃O⁺ ion donors are chosen from amongst the acids having a pK_a of between 0 and 2.5 inclusive at 22°

C. and more particularly chosen from amongst H₂SO₃, HSO₄—

, H₃PO₄, oxalic acid or mixtures thereof, and even more preferentially amongst the acids forming bivalent cation salts, such as calcium, which are almost insoluble in water, that is to say with a solubility of less than 0.01% by weight.

6. A mineral pigment according to claim 1, characterized in that a BET specific surface area of between 25 m²/g and 200 m²/g measured according to ISO 9277, preferentially between 30 m²/g and 80 m²/g and highly preferentially between 35 m²/g and 60 m²/g, and a median diameter, determined by a measurement with the Sedigraph™

5100, between 0.1 and 50 micrometers, preferentially between 0.5 and 40 micrometers and highly preferentially between 1 and 10 micrometers.

7. An aqueous suspension of mineral pigment, characterized in that it contains the mineral pigment according to claim 1.

35. A mass filler used in the manufacture of non-coated paper sheet and/or as a base of coating formulation in the operations of surface treatment of paper and/or coating of paper comprising the mineral pigment according to claim 1.

36. A mass filler used in the manufacture of a sheet of non-coated paper and/or as a base of coating formulation in the operations of surface treatment of paper and/or coating of paper comprising the aqueous suspension according to claim 7.

37. A paper for inkjet printing, comprising the mineral pigment according to claims 1 in the mass and/or in the coating.

38. A paper for inkjet printing, comprising the aqueous suspension according to claim 7 in the mass and/or in the coating.

8. A method of manufacturing a mineral pigment in the dry state or in aqueous suspension containing a product formed in situ by the double and/or multiple reaction between a calcium carbonate and the reaction product or products of the said carbonate with gaseous CO₂ formed in situ and/or coming from an external supply, and the reaction product or products of the said carbonate with one or more moderately strong to strong H₃O⁺ ion donors and at least one aluminium silicate and/or at least one synthetic silica and/or at least one calcium silicate and/or at least one silicate of a monovalent salt such as sodium silicate and/or potassium silicate and/or lithium silicate, preferably such as sodium silicate and/or at least one aluminium hydroxide and/or at least one sodium and/or potassium aluminate containing less than 0.1% by weight of silicate of a monovalent salt such as sodium, potassium or lithium silicate or mixtures thereof, preferably such as sodium silicate, relative to the dry weight of calcium carbonate, characterized in that it comprises the following steps:

a) the treatment of the calcium carbonate in aqueous phase with the moderately strong to strong H₃O⁺ ion donor or donors and the treatment with the gaseous CO₂ formed in situ and/or coming from an external supply, which treatment which is an integral part of step a),

b) the addition, prior to and/or simultaneous with step a), of at least one aluminium silicate and/or at least one synthetic silica and/or at least one calcium silicate and/or at least one silicate of a monovalent salt such as sodium silicate and/or potassium silicate and/or lithium silicate, preferably such as sodium silicate, and possibly the prior and/or simultaneous addition of a sodium and/or potassium aluminate,

c) possibly the addition of a base, preferentially a bivalent ion base, highly preferentially lime and/or calcium carbonate in dry form or in aqueous suspension possibly containing one or more anionic, cationic and/or weakly anionic dispersing agents,

d) possibly putting in anionic aqueous suspension the product obtained in step b) or c) at a concentration of dry matter of between 1% and 80% using possibly at least one anionic electrolyte,

e) possibly putting the product obtained in step b) or c) in cationic aqueous suspension by the addition of at least one cationic electrolyte,

f) possibly putting the product obtained in step b) or c) in weakly anionic aqueous suspension by the addition of at least one weakly anionic electrolyte,

g) possibly drying after one of steps c) to f).

9. A method of manufacturing a mineral pigment according to claim 8, characterized in that the calcium carbonate is a natural calcium carbonate or a mixture of natural calcium carbonate with talc, kaolin, titanium dioxide, magnesium dioxide or any mineral which is inert vis-à

-vis moderately strong to strong H₃O⁺ ion donors.

10. A method of manufacturing a mineral pigment according to claim 9, characterized in that the natural calcium carbonate is chosen from amongst a marble, a calcite, a chalk, a dolomite or mixtures thereof.

11. A method of manufacturing a mineral pigment according to claim 8, characterized in that the moderately strong to strong H₃O⁺ ion donor or donors are chosen from amongst the moderately strong to strong acids, or mixtures thereof generating H₃O⁺ ions.

12. A method of manufacturing a mineral pigment according to claims 8, characterized in that the strong acids are preferentially chosen from amongst the acids having a pK_a of less than or equal to zero at 22°

C. and more particularly chosen from amongst sulphuric acid, hydrochloric acid or mixtures thereof and characterized in that the moderately strong H₃O⁺ ion donor or donors are chosen from amongst the acids having a pK_a of between 0 and 2.5 inclusive at 22°

C. and more particularly chosen from amongst H₂SO₃, HSO₄⁻

, H₃PO₄, oxalic acid or mixtures thereof, or even more preferentially from amongst the acids forming bivalent cation salts, such as calcium, which are almost insoluble in water, that is to say with a solubility of less than 0.01% by weight.

13. A method of manufacturing a mineral pigment according to claim 8, characterized in that the strong acid or acids can be mixed with the moderately strong acid or acids.

14. A method of manufacturing a mineral pigment according to claim 8, characterized in that the molar quantity of moderately strong to strong H₃O⁺ ion donors relative to the number of moles of CaCO₃ is in total between 0.05 and 1, preferentially between 0.1 and 0.5.

15. A method of manufacturing a mineral pigment according to claim 8, characterized in that step a) and/or step b) can be repeated several times.

16. A method of manufacturing a mineral pigment according to claim 8, characterized in that the temperature during step a) of the treatment is between 5°

C. and 100°

C., and preferentially between 65°

C. and 90°

C.

17. A method of manufacturing a mineral pigment according to claim 16, characterized in that the duration of steps a) to c) of the treatment is from 0.01 hours to 24 hours.

18. A method of manufacturing a mineral pigment according to claim 17, characterized in that the duration of steps a) to c) of the treatment is from 0.2 hours to 6 hours.

19. A method of manufacturing a mineral pigment according to claim 17, characterized in that, between one hour and twenty-four hours after the end of the treatment, the pH is greater than 7.5 and the amount of monovalent salt silicate such as sodium, potassium or lithium silicate or mixtures thereof is less than 0.1% by weight relative to the dry weight of calcium carbonate.

20. A method of manufacturing a mineral pigment according to claim 19, characterized in that, between one hour and five hours after the end of the treatment, the pH is greater than 7.5 and the amount of monovalent salt silicate such as sodium, potassium or lithium silicate or mixtures thereof is less than 0.1% by weight relative to the dry weight of calcium carbonate.

21. A method of manufacturing a mineral pigment according to claim 8, characterized in that it is implemented in aqueous phase at low dry matter concentrations, moderately strong or strong, preferentially for a dry matter content of between 0.3% and 80% by weight, highly preferentially between 15% and 60%.

22. A method of manufacturing a mineral pigment according to claim 8, characterized in that step b) is an addition of 0.1% to 25%, preferentially 5 to 10% by dry weight relative to the dry weight of calcium carbonate.

23. A method of manufacturing a mineral pigment according to claim 8, characterized in that step d) uses from 0.05% to 5.0% by dry weight of an anionic electrolyte chosen from amongst the homopolymers or copolymers in the non-neutralised, partially neutralised or completely neutralised acidic state, of ethylenically unsaturated monomers with a monocarboxylic function such as acrylic or methacrylic acid or the hemiesters of diacids such as C₁ to C₄ monoesters of maleic or itaconic acids, or mixtures thereof, or with a dicarboxylic function chosen from amongst the ethylenically unsaturated monomers with a dicarboxylic function such as crotonic, isocrotonic, cinnamic, itaconic or maleic acid, or anhydrides of carboxylic acids such as maleic anhydride or with a sulphonic function chosen from amongst ethylenically unsaturated monomers with a sulphonic function such as acrylamido-methyl-propane-sulphonic acid, sodium methallylsulphonate, vinyl sulphonic acid and styrene sulphonic acid or with a phosphoric function chosen from amongst ethylenically unsaturated monomers with a phosphoric function such as vinyl phosphoric acid, ethylene glycol methacrylate phosphate, propylene glycol methyacrylate phosphate, ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate and ethoxylates thereof or with a phosphonic function chosen from amongst ethylenically unsaturated monomers with a phosphonic function such as vinyl phosphonic acid or mixtures thereof or polyphosphates.

24. A method of manufacturing a mineral pigment according to claim 8, characterized in that step e) uses from 0.05% to 5.0% by dry weight of a cationic electrolyte chosen from amongst the homopolymers or copolymers of ethylenically unsaturated cationic monomers or quaternary ammonium such as [2-(methacryloyloxy) ethyl]trimethyl ammonium sulphate or chloride, [2-(acryloyloxy)ethyl]trimethyl ammonium chloride or sulphate, [3-(acrylamido) propyl]trimethyl ammonium chloride or sulphate, dimethyl diallyl ammonium chloride or sulphate, or [3-(methacrylamido)propyl]trimethyl ammonium chloride or sulphate.

25. A method of manufacturing a mineral pigment according to claim 8, characterized in that step f) uses 0.05% to 5.0% by dry weight of a weakly anionic electrolyte chosen from amongst the weakly ionic and water-soluble copolymers composed of:

a) at least one anionic monomer with a carboxylic or dicarboxylic or phosphoric or phosphonic or sulphonic function or a mixture thereof,

b) at least one non-ionic monomer, the non-ionic monomer consisting of at least one monomer of formula (I);

in which;

m and p represent a number of alkylene oxide units less than or equal to 150,

n represents a number of ethylene oxide units less than or equal to 150,

q represents an integer number at least equal to 1 and such that 5≦

(m+n+p)_q≦

150, and preferentially such that 15≦

(m+n+p)_q≦

120,

R₁ represents hydrogen or the methyl or ethyl radical,

R₂ represents hydrogen or the methyl or ethyl radical,

R represents a radical containing a polymerisable unsaturated function, preferentially belonging to the vinyl group and to the group of acrylic, methacrylcic, maleic, itaconic, crotonic or vinylphthalic esters as well as to the group of urethane unsaturates such as acrylurethane, methacrylurethane, α

-α

′

dimethyl-isopropenyl-benzylurethane, or allylurethane, and to the group of allyl or vinyl ethers, whether or not substituted, or to the group of ethylenically unsaturated amides or imides,

R′

represents hydrogen or a hydrocarbon radical having 1 to 40 carbon atoms, and preferentially represents a hydrocarbon radical having 1 to 12 carbon atoms and highly preferentially a hydrocarbon radical having 1 to 4 carbon atoms, or a mixture of several monomers of formula (I),

c) possibly at least one monomer of the acrylamide or methacrylamide type or derivatives thereof such as N-[3-(dimethylamino)propyl]acrylamide or N-[3-(dimethylamino)propyl]methacrylamide, and mixtures thereof, or at least one non-water soluble monomer such as alkyl acrylates or methyacrylates, unsaturated esters such as N-[2-(dimethylamino)ethyl]methacrylate, or N-[2-(dimethylamino)ethyl]acrylate, vinyls such as vinyl acetate, vinylpyrrolidone, styrene, alphamethylstyrene and derivatives thereof, or at least one cationic monomer or quaternary ammonium such as [2-(methacryloyloxy) ethyl]trimethyl ammonium chloride or sulphate, [2-(acryloyloxy)ethyl]trimethyl ammonium chloride or sulphate, [3-(acrylamido)propyl]trimethyl ammonium chloride or sulphate, dimethyl diallyl ammonium chloride or sulphate, [3-(methacrylamido) propyl]trimethyl ammonium chloride or sulphate, or at least one organofluorinated or organosililated monomer, or a mixture of several of these monomers,

d) possibly at least one monomer possessing at least two ethylenic unsaturations referred to in the remainder of the application as a cross-linking monomer.

26. A mineral pigment in the dry state or in aqueous suspension containing a product formed in situ by the double and/or multiple reaction between a calcium carbonate and the reaction product or products of the said carbonate with gaseous CO₂ formed in situ and/or coming from an external supply, and the reaction product or products of the said carbonate with one or more moderately strong to strong H₃O⁺ ion donors and at least one aluminium silicate and/or at least one synthetic silica and/or at least one calcium silicate and/or at least one silicate of a monovalent salt such as sodium silicate and/or potassium silicate and/or lithium silicate, preferably such as sodium silicate and/or at least one aluminium hydroxide and/or at least one sodium and/or potassium aluminate, characterized in that it is obtained by the method according to claim 8.

27. A mineral pigment according to claim 26, characterized in that it has a BET specific surface area of between 25 m²/g and 200 m²/g measured according to ISO 9277, preferentially between 30 m²/g and 80 m²/g and highly preferentially between 35 m²/g and 60 m²/g, and a median diameter, determined by a measurement with the Sedigraph™

5100, of between 0.1 and 50 micrometers, preferentially between 0.5 and 40 micrometers and highly preferentially between 1 and 10 micrometers.

28. An aqueous suspension of mineral pigment according to claim 26 obtained according to step d), characterized in that the mineral pigment has a BET specific surface area of between 25 m²/g and 200 m²/g measured in accordance with ISO 9277, preferentially between 30 m²/g and 80 m²/g and highly preferentially between 35 m²/g and 60 m²/g, and a median diameter, determined by a measurement with the Sedigraph™

5100, of between 0.1 and 50 micrometers, preferentially between 0.5 and 40 micrometers and highly preferentially between 1 and 10 micrometers, and in that the suspension has a dry matter content of between 0.3% and 80%, preferentially between 15% and 60% and in that it contains 0.05% to 5.0% by dry weight, relative to the dry weight of calcium carbonate, of at least one anionic electrolyte.

29. An aqueous suspension according to claim 25, characterized in that the anionic electrolyte is chosen from amongst the homopolymers or copolymers in the non-neutralised, partially neutralised or completely neutralised acidic state, of ethylenically unsaturated monomers with a monocarboxylic function such as acrylic or methacrylic acid or the hemiesters of diacids such as C₁ to C₄ monoesters of maleic or itaconic acids, or mixtures thereof, or with a dicarboxylic function chosen from amongst the ethylenically unsaturated monomers with a dicarboxylic function such as crotonic, isocrotonic, cinnamic, itaconic or maleic acid, or anhydrides of carboxylic acids such as maleic anhydride or with a sulphonic function chosen from amongst ethylenically unsaturated monomers with a sulphonic function such as acrylamido-methyl-propane-sulphonic acid, sodium methallylsulphonate, vinyl sulphonic acid and styrene sulphonic acid or with a phosphoric function chosen from amongst ethylenically unsaturated monomers with a phosphoric function such as vinyl phosphoric acid, ethylene glycol methacrylate phosphate, propylene glycol methyacrylate phosphate, ethylene glycol acrylate phosphate, propylene glycol acrylate phosphate and ethoxylates thereof or with a phosphonic function chosen from amongst ethylenically unsaturated monomers with a phosphonic function such as vinyl phosphonic acid or mixtures thereof or polyphosphates.

30. An aqueous suspension of the mineral pigment according to claim 26 obtained according to step e), characterized in that the mineral pigment has a BET specific surface area of between 25 m²/g and 200 m²/g measured in accordance with ISO 9277, preferentially between 30 m²/g and 80 m²/g and highly preferentially between 35 m2/g and 60 m²/g, and a median diameter, determined by a measurement with the Sedigraph™

5100, of between 0.1 and 50 micrometers, preferentially between 0.5 and 40 micrometers and highly preferentially between 1 and 10 micrometers, and in that the suspension has a dry matter content of between 0.3% and 80%, preferentially between 15% and 60% and in that it contains 0.1% to 5.0% by dry weight, relative to the dry weight of calcium carbonate, of at least one cationic electrolyte.

31. An aqueous suspension according to claim 30, characterized in that the cationic electrolyte is chosen from amongst the homopolymers or copolymers of ethylenically unsaturated cationic monomers or quaternary ammonium such as [2-(methacryloyloxy)ethyl]trimethyl ammonium sulphate or chloride, [2-(acryloyloxy)ethyl]trimethyl ammonium chloride or sulphate, [3-(acrylamido)propyl]trimethyl ammonium chloride or sulphate, dimethyl diallyl ammonium chloride or sulphate, or [3-(methacrylamido)propyl]trimethyl ammonium chloride or sulphate.

32. An aqueous suspension of the mineral pigment according to claims 26 obtained according to step f), characterized in that the mineral pigment has a BET specific surface area of between 25 m²/g and 200 m²/g measured in accordance with ISO 9277, preferentially between 30 m²/g and 80 m²/g and highly preferentially between 35 m²/g and 60 m²/g, and a median diameter, determined by a measurement with the Sedigraph™

5100, of between 0.1 and 50 micrometers, preferentially between 0.5 and 40 micrometers and highly preferentially between 1 and 10 micrometers, and in that the suspension has a dry matter content of between 0.3% and 80%, preferentially between 15% and 60% and in that it contains 0.05% to 5.0% by dry weight, relative to the dry weight of calcium carbonate, of at least one weakly anionic electrolyte.

33. An aqueous suspension according to claim 32, characterized in that the weakly anionic electrolyte is chosen from amongst the weakly ionic and water-soluble copolymers composed of:

a) at least one anionic monomer with a carboxylic or dicarboxylic or phosphoric or phosphonic or sulphonic function or a mixture thereof,

b) at least one non-ionic monomer, the non-ionic monomer consisting of at least one monomer of formula (I);

in which;

m and p represent a number of alkylene oxide units less than or equal to 150,

n represents a number of ethylene oxide units less than or equal to 150,

q represents an integer number at least equal to 1 and such that 5≦

(m+n+p)q≦

150, and preferentially such that 15≦

(m+n+p)q≦

120,

R₁ represents hydrogen or the methyl or ethyl radical,

R₂ represents hydrogen or the methyl or ethyl radical,

R represents a radical containing a polymerisable unsaturated function, preferentially belonging to the vinyl group and to the group of acrylic, methacrylcic, maleic, itaconic, crotonic or vinylphthalic esters as well as to the group of urethane unsaturates such as acrylurethane, methacrylurethane, α

-α

′

dimethyl-isopropenyl-benzylurethane, or allylurethane, and to the group of allyl or vinyl ethers, whether or not substituted, or to the group of ethylenically unsaturated amides or imides,

R′

represents hydrogen or a hydrocarbon radical having 1 to 40 carbon atoms, and preferentially represents a hydrocarbon radical having 1 to 12 carbon atoms and highly preferentially a hydrocarbon radical having 1 to 4 carbon atoms,

or a mixture of several monomers of formula (I),

c) possibly at least one monomer of the acrylamide or methacrylamide type or derivatives thereof such as N-[3-(dimethylamino)propyl]acrylamide or N-[3-(dimethylamino)propyl]methacrylamide, and mixtures thereof, or at least one non-water soluble monomer such as alkyl acrylates or methyacrylates, unsaturated esters such as N-[2-(dimethylamino)ethyl]methacrylate, or N-[2-(dimethylamino)ethyl]acrylate, vinyls such as vinyl acetate, vinylpyrrolidone, styrene, alphamethylstyrene and derivatives thereof, or at least one cationic monomer or quaternary ammonium such as [2-(methacryloyloxy)ethyl]trimethyl ammonium chloride or sulphate, [2-(acryloyloxy)ethyl]trimethyl ammonium chloride or sulphate, [3-(acrylamido)propyl]trimethyl ammonium chloride or sulphate, dimethyl diallyl ammonium chloride or sulphate, [3-(methacrylamido)propyl]trimethyl ammonium chloride or sulphate, or at least one organofluorinated or organosililated monomer, or a mixture of several of these monomers,

d) possibly at least one monomer possessing at least two ethylenic unsaturations referred to in the remainder of the application as a cross-linking monomer.

34. A mineral pigment according to claim 26, characterized in that it is in dry form.