Process of manufacture of particles with a natural calcium carbonate and ethylene acrylic acid salts base, suspensions and dry pigments obtained, their uses

Abstract

The present invention consists of a process of preparation of at least one mineral matter and/or of at least one pigment, including a calcium carbonate made at once partially organophilic and partially hydrophilic, in which the carbonate is blended and/or ground and/or concentrated in an aqueous medium, in the presence of at least one salt of ethylene acrylic acid, one dispersing agent and/or one grinding aid agent, which is introduced before and/or during this treatment stage. Another object of the invention lies in the aqueous dispersions and suspensions of calcium carbonate thus obtained. They may be dried and the dry pigments obtained also constitute an object of the invention. Use of these aqueous dispersions and these dry pigments in the field of plastic, paints and paper constitutes another object of the invention.

Claims

1. An aqueous suspension or dispersion of mineral matter comprising calcium carbonate and at least one salt of ethylene acrylic acid, wherein the carboxylic groupings of the ethylene acrylic acid salt are entirely neutralized or neutralized at a rate of 70 to 99% relative to the total number of the carboxylic sites of the ethylene acrylic acid, with at least one neutralization agent that includes one or more amines, wherein the suspension or dispersion has a dry weight of greater than 65% based on the total weight of the aqueous suspension or dispersion of mineral matter, wherein the ethylene acrylic acid salt has a mass ratio of ethylene monomer to acrylic acid monomer of between 10:90 and 30:70, wherein the ethylene acrylic acid salt has a melt index of between 50 g/10 minutes and 1,500 g/10 minutes when the ethylene acrylic acid salt is totally neutralized, and wherein the ethylene acrylic acid salt has a melt index of between 1,000 g/10 minutes and 1,400 g/10 minutes when the ethylene acrylic acid salt is neutralized at a rate of 70 to 99%.

2. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the salt of the ethylene acrylic acid is present at a dry weight percent of 0.2 to 2% based on the dry weight of mineral matter.

3. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the amine includes one primary amine.

4. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the amine is an alkanolamine.

5. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the amine is 2-amino-2-methyl-1-propanol and/or dimethylethanolamine.

6. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the amine is 2-amino-2-methyl-1-propanol.

7. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the amine is dimethylethanolamine.

8. The aqueous suspension or dispersion of mineral matter according to claim 1, having a dry weight of greater than 70% based on the total weight of the aqueous suspension or dispersion of mineral matter.

9. The aqueous suspension or dispersion of mineral matter according to claim 1, having a dry weight of greater than 75% based on the total weight of the aqueous suspension or dispersion of mineral matter.

10. The aqueous suspension or dispersion of mineral matter according to claim 1, having a dry weight of between 75 and 78% based on the total weight of the aqueous suspension or dispersion of mineral matter.

11. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter comprises natural and/or precipitated calcium carbonate.

12. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter comprises natural calcium carbonate.

13. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter includes, in addition to calcium carbonate, at least one other mineral matter selected from a dolomite, a bentonite, a kaolin, talc, cement, gypsum, lime, magnesia, titanium dioxide, satin white, aluminium trioxide, aluminium trihydroxide, a silica, mica, a talc-calcium carbonate blend, a calcium carbonate-kaolin blend, a blend of calcium carbonate with aluminium trihydroxide or aluminium trioxide, a blend of calcium carbonate with a synthetic or natural fiber, a mineral costructure, a talc-calcium carbonate costructure, or a talc-titanium dioxide costructure, or any blend thereof.

14. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter comprises greater than or equal to 70% of calcium carbonate based on the total dry weight of the mineral matter.

15. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter has an average diameter of less than 15 m.

16. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter has an average diameter of less than 5 m.

17. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter has an average diameter of between 0.3 and 1.7 m.

18. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the mineral matter has an average diameter of between 0.9 and 0.9 m.

19. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein greater than 60% of particles of the mineral matter has a diameter of less than 2 m.

20. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein greater than 90% of particles of the mineral matter has a diameter of less than 2 m.

21. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein greater than 99% of particles of the mineral matter has a diameter of less than 2 m.

22. The aqueous suspension or dispersion of mineral matter according to claim 1, having a Brookfield viscosity of less than 1,000 mPa.Math.s measured at 100 rpms at 25 C.

23. The aqueous suspension or dispersion of mineral matter according to claim 1, having a Brookfield viscosity of less than 500 mPa.Math.s measured at 100 rpms at 25 C.

24. The aqueous suspension or dispersion of mineral matter according to claim 1, having a Brookfield viscosity of between 100 and 300 mPa.Math.s measured at 100 rpms at 25 C.

25. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the salt of ethylene acrylic acid is a salt soluble in an aqueous medium.

26. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the ethylene acrylic acid salt has a melt index of between 200 g/10 minutes and 300 g/10 minutes when the ethylene acrylic acid salt is totally neutralized.

27. The aqueous suspension or dispersion of mineral matter according to claim 1, which further comprises a dispersing and/or grinding aid agent.

28. The aqueous suspension or dispersion of mineral matter according to claim 1, wherein the dispersing and/or grinding aid agent is present at a dry weight percent of 0.1 to 2% based on the dry weight of the mineral matter.

29. The aqueous suspension or dispersion of mineral matter according to claim 27, wherein the dispersing agent and/or grinding aid agent is a homopolymer of acrylic acid and/or a copolymer of acrylic acid with a water-soluble monomer selected from methacrylic acid, maleic acid, itaconic acid, crotonic acid, fumaric acid, isocrotonic acid, aconitic acid, mesaconic acid, sinapic acid, undecylenic acid, angelic acid, canellic acid and/or 2-acrylamido 2-methyl propane sulfonic acid in acid form or partially neutralized, or acrylamide, methylacrylamide, an ester of an acrylic or methacrylic acid, acrylate phosphate, ethylene methacrylate, propylene glycol, vinylpyrrolidone, vinylcaprolactame, vinyl acetate, sodium styrene sulfonate, allylamine, or derivative thereof.

Description

EXAMPLES

Example 1

(1) This example illustrates the process according to the invention, in which a natural calcium carbonate is treated by a salt of ethylene acrylic acid during a stage of grinding in an aqueous medium, where a dispersing agent is introduced during the said grinding stage.

(2) In relation thereto, this example starts by describing the copolymers of the ethylene acrylic acid used, followed by the manufacture of certain of their salts.

(3) Note: all the granulometric characteristics of the calcium carbonate suspensions were measured using a device of the Sedigraph 5100 type sold by the company MICROMERITICS.

(4) Copolymer of Ethylene Acrylic Acid a)

(5) This copolymer designates a copolymer of ethylene acrylic acid comprised 20% by weight of acrylic acid and 80% by weight of ethylene.

(6) Copolymer of Ethylene Acrylic Acid b)

(7) This copolymer designates a copolymer of ethylene acrylic acid comprised 20% by weight of acrylic acid and 80% by weight of ethylene.

(8) This copolymer has a melt index of 1,300 g/10 minutes, measured according to norm ASTM 1238 125 C./2.16 kg.

(9) It is well known that a high melt index corresponds to a low molecular weight.

(10) Copolymer of Ethylene Acrylic Acid c)

(11) This copolymer designates a copolymer of ethylene acrylic acid comprised 20% by weight of acrylic acid and 80% by weight of ethylene.

(12) This copolymer has a melt index of 300 g/10 minutes, measured according to norm ASTM 1238 125 C./2.16 kg.

(13) The viscosities (mPa.Math.s) of these different copolymers are indicated in table 1, as a function of temperature. These rheological properties give a basis of comparison of the molecular weights of these copolymers: a low viscosity indicates a low molecular weight.

(14) These viscosity values were measured at the temperatures indicated below with a rheometer sold under the name MCR 300 by the company PHYSICA with the following conditions: cone-plane rheometer CP50-1, with a constant shearing rate equal to 5 s.sup.1, in a temperature interval ranging from 200 C. to 120 C., in steps of 0.0833 C./s.

(15) TABLE-US-00001 TABLE 1 viscosities of the different copolymers of ethylene acrylic acid as a function of temperature Viscosity Viscosity Viscosity Temperature (mPa .Math. s) of (mPa .Math. s) of (mPa .Math. s) of ( C.) copolymer a) copolymer b) copolymer c) 200 24,300 5,200 21,700 190 37,300 7,850 33,400 180 56,300 11,600 50,100 170 88,300 17,300 74,500 160 138,000 25,100 109,000 150 225,000 43,000 190,000 140 367,000 72,900 326,000 130 628,000 127,000 568,000
Solution of Ethylene Acrylic Acid No. 1

(16) 500 grams of copolymer a) are added into 2.5 liters of deionised water in a 10-liter reactor of the ESCO type.

(17) While stirring, 123.7 grams of 2-amino-2-methyl-1-propanol (so as to neutralise 100% the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(18) A clear and limpid solution is thus obtained.

(19) Solution of Ethylene Acrylic Acid No. 2

(20) 500 grams of copolymer a) are added into 2.5 liters of deionised water in a 10-liter reactor of the ESCO type.

(21) While stirring, 130.2 grams of di-methyl ethanolamine (so as to neutralise 100% the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(22) A clear and limpid solution is thus obtained.

(23) Solution of Ethylene Acrylic Acid No. 3

(24) 500 grams of copolymer b) are added into 5 liters of deionised water in a 10-liter reactor of the ESCO type.

(25) While stirring, 38.8 grams of soda (so as to neutralise 75% the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(26) A clear and limpid solution is thus obtained.

(27) Solution of ethylene acrylic acid No. 4

(28) 500 grams of copolymer b) are added into 5 liters of deionised water in a 10-liter reactor of the ESCO type.

(29) While stirring, 55.4 grams of soda (so as to neutralise all the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(30) A clear and limpid solution is thus obtained.

(31) Solution of Ethylene Acrylic Acid No. 5

(32) 500 grams of copolymer c) are added into 5 liters of deionised water in a 10-liter reactor of the ESCO type.

(33) While stirring, 54.1 grams of soda (so as to neutralise all the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(34) A clear and limpid solution is thus obtained.

(35) Solution of Ethylene Acrylic Acid No. 6

(36) 500 grams of copolymer b) are added into 2.5 liters of deionised water in a 10-liter reactor of the ESCO type.

(37) While stirring, 200 grams of ammonia (so as to neutralise 100% the carboxylic acid sites of the ethylene acrylic acid) were added, and the blend was heated for one hour at 98 C.

(38) A clear and limpid solution is thus obtained.

(39) Test No. 1a

(40) This test illustrates the prior art.

(41) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(42) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 0.65% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble.

(43) The grinding required 11 minutes/kg.

(44) An aqueous suspension of marble is obtained the dry extract of which is equal to 75.5%, and the size of the particles of which is such that 90% by weight of them have a diameter of less than 2 m.

(45) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 251 mPa.Math.s.

(46) This viscosity is measured on a DVII+ device, in a 1-liter container; this procedure will be used in the other tests.

(47) The screen residue of greater than 45 m was 40 ppm.

(48) Test No. 1b

(49) This test illustrates the prior art.

(50) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(51) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, in the presence of 1.0% by dry weight of the solution of ethylene acrylic acid No. 6.

(52) An aqueous suspension of marble is obtained the dry extract of which is equal to 38.0%, and the size of the particles of which is such that 73% by weight of them have a diameter of less than 2 m. It is impossible to increase the dry extract without impairing the viscosity as indicated below.

(53) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is between 250 and 600 mPa.Math.s.

(54) Test No. 2

(55) This test illustrates the invention.

(56) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(57) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 0.67% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble, and in the presence of 0.5% by dry weight of the solution of ethylene acrylic acid No. 1.

(58) An aqueous suspension of marble is obtained the dry extract of which is equal to 75.7%, and the size of the particles of which is such that 89% by weight of them have a diameter of less than 2 m.

(59) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 150 mPa.Math.s.

(60) The screen residue of greater than 45 m was 13 ppm.

(61) Test No. 3

(62) This test illustrates the invention.

(63) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(64) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 1.04% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble, and in the presence of 0.5% by dry weight of the solution of ethylene acrylic acid No. 2.

(65) The grinding required 11.3 minutes/kg.

(66) An aqueous suspension of marble is obtained the dry extract of which is equal to 76.1%, and the size of the particles of which is such that 92% by weight of them have a diameter of less than 2 m.

(67) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 160 mPa.Math.s.

(68) Test No. 4

(69) This test illustrates the invention.

(70) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(71) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 1.00% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble, and in the presence of 0.5% by dry weight of the solution of ethylene acrylic acid No. 3.

(72) An aqueous suspension of marble is obtained the dry extract of which is equal to 74.1%, and the size of the particles of which is such that 90% by weight of them have a diameter of less than 2 m.

(73) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 153 mPa.Math.s.

(74) The screen residue of greater than 45 m was 59 ppm.

(75) Test No. 5

(76) This test illustrates the invention.

(77) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(78) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 1.00% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble, and in the presence of 0.5% by dry weight of the solution of ethylene acrylic acid No. 4.

(79) An aqueous suspension of marble is obtained the dry extract of which is equal to 77.0%, and the size of the particles of which is such that 91% by weight of them have a diameter of less than 2 m.

(80) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 157 mPa.Math.s.

(81) Test No. 6

(82) This test illustrates the invention.

(83) It uses a marble of Norway, the average diameter of the particles of which is equal to 45 m.

(84) This marble was ground in an aqueous medium in a grinder of the Dynomill type of 1.4 liters with 2,700 grams of zirconium dioxide-based grinding balls of diameter of between 0.6 and 1 mm, and in the presence of 1.00% by dry weight of a homopolymer of acrylic acid neutralised by sodium and magnesium, and of molecular weight equal to 5,400 g/mole, relative to the dry weight of marble, and in the presence of 0.5% by dry weight of the solution of ethylene acrylic acid No. 5.

(85) An aqueous suspension of marble is obtained the dry extract of which is equal to 76.9%, and the size of the particles of which is such that 89% by weight of them have a diameter of less than 2 m.

(86) The Brookfield viscosity measured at 25 C. and at 100 revolutions/minute with mobile number 3 is 187 mPa.Math.s.

(87) The results demonstrate that the process according to the invention leads to suspensions of calcium carbonate treated with a salt of ethylene acrylic acid and a dispersing agent, having a high dry extract, and notably greater than 75%.

(88) In addition, this dry extract is greater than that obtained in the process according to the prior art, and the Brookfield viscosities measured at 25 C. and at 100 revolutions/minute are lower than those obtained in the case of the prior art.

(89) In addition, it was demonstrated that the grinding is as efficient with or without ethylene acrylic acid, by a comparison between tests No. 1 a and 3.

(90) In addition, no example according to the invention presented a problem of creation of foam in the calcium carbonate suspension.

(91) Moreover, it was observed that the screen residues obtained in the case of the invention were completely negligible.

(92) Test No. 7

(93) This test illustrates the prior art.

(94) A high-density polyethylene of the company BASELL POLYOLEFINS sold under the name Hostalen GM 9240 HT was introduced into a roll mill sold under the name Walzwerk 150400 of the company DR. COLLIN.

(95) After this, plates 2 and 4 mm in thickness were formed in a Testing Platen Presses Type P P300-P press of the company DR. COLLIN.

(96) Test No. 8

(97) This test illustrates the invention.

(98) The suspension of test No. 5 was dried with an MSD 100 pulveriser of the company NIRO. A dry treated marble is obtained, the size of the particles of which is such that 88% by weight of them have a diameter of less than 2 m.

(99) The treated and dry marble was then blended at 180 C. with a high-density polyethylene of the company BASELL POLYOLEFINS sold under the name Hostalen GM 9240 HT in a roll mill sold under the name Walzwerk 150400 of the company DR. COLLIN. The composition of the blend has equal masses of the treated product and of the high-density polyethylene.

(100) After this, plates 2 and 4 mm in thickness were formed in a Testing Platen Presses Type P P300-P press of the company DR. COLLIN.

(101) The traction resistances of the plates formed for tests No. 7 and 8 are equal respectively to 23.9 N/mm.sup.2 and 24.2 N/mm.sup.2 according to norm DIN 53455.

(102) It is observed that the replacement of part of the polyethylene by the pigment according to the invention does not reduce the traction resistance.