JP2005536426A - Stabilized aqueous silicon dioxide dispersion - Google Patents

Abstract

In aqueous dispersions containing silicon dioxide powder, where the dispersions are stable in the range of pH values 2-6, in which case they are at least partially stable cation-feeding compounds in this pH range And the zeta potential is 0 or less. They are produced by contacting silicon dioxide powder and at least one cation-providing compound while moving the aqueous medium. The dispersion can be used for chemical-mechanical polishing of metal surfaces.

Description

  The present invention relates to an aqueous dispersion containing silicon dioxide, which is stable in the acidic pH range, a process for its production and its use. The invention further relates to a powder that can be used for the production of dispersions.

  Silicon dioxide dispersions are generally not stable in the acidic pH range. As a method for stabilization, for example, it can be considered to add an aluminum compound to the dispersion.

  WO 00/20221 discloses an aqueous silicon dioxide solution that is stable in the acidic range. This is produced by contacting silicon dioxide particles with an aluminum compound in an aqueous medium. The amount of aluminum compound required to produce the dispersion claimed in WO 00/20221 is tracked by increasing the zeta potential and whether the rise of the zeta potential curve moves in the direction of zero. Or achieved by reaching a plateau. WO 00/20221 claims a dispersion in which the zeta potential only achieves 50% of the maximum achievable. In each case, the zeta potential of the claimed dispersion has a strong positive value up to 30 mV. This means that silicon dioxide particles, which are inherently negatively charged, are completely cationized by the addition of an aluminum compound. Despite the good stability of the claimed dispersion, the silicon dioxide dispersion is no longer covered at the surface with positively charged aluminum species. This is a disadvantage in the above application that the dispersion can come into contact with the anionic material or dispersion. This can lead to, for example, undesirable agglomeration or precipitation.

On the other hand, US 2892797 discloses aqueous silicon dioxide dispersions, in which case they are stabilized by treatment with alkali metalates. Sodium aluminate is particularly preferred. Stabilization is performed by an anion, for example [Al (OH) ₄ ] ⁻ . The dispersion is usually stable in the pH range of 5-9. Therefore, the zeta potential of the treated powder is negative. Subsequent removal of the cations, for example by an ion exchange step, can be a disadvantage of this method. For certain applications, such as chemical-mechanical polishing, alkali cations are generally not preferred. Another drawback is low stability in more acidic media below pH 5.

  The object of the present invention is to provide a silicon dioxide dispersion that is stable in the acidic range without reversing the properties of silicon dioxide by reversing the charge on the particle surface.

The present invention provides an aqueous dispersion containing silicon dioxide powder having a silicon dioxide content of 10 to 60% by weight, wherein
The dispersion is stable in the pH range of 2-6,
The dispersion additionally contains at least one compound, in which case they are at least partly in aqueous solution and are stable in the form of polyvalent cations in the pH range 2-6. In this case, the cation is stable in a silicate-like environment as an anion component on the particle surface of the silicon dioxide powder,
The amount of cation donating compound relative to the silicon dioxide surface is 0.001 to 0.1 mg cation donating compound / m ² silicon dioxide surface, the cation donating compound being calculated as oxide And
The zeta potential of the dispersion has a value of 0 or less.

  The zeta potential is an active potential around the particle and indicates a measure of electrostatic interaction between individual particles. This partly acts on the stabilization of the suspension, in particular on the stabilization of the dispersion containing the dispersed ultrafine particles. The zeta potential is determined, for example, by measuring the colloidal vibration current (CVI) of the dispersion or by measuring its electrophoretic mobility.

  The cation donating compounds according to the invention are usually rendered soluble at least partially in the form of multivalent cations in aqueous solutions in the range of pH 2-6, in which case these cations are anionic centers. It is stable in a silicate-like environment. These are compounds having Ca, Sr, Ba, Be, Mg, Zn, Mn, Ni, Co, Sn, Pb, Fe, Cr, Al, Sc, Ce, Ti, and Zr as cations.

  A silicate-like environment means that the metal cations are present in the form of metal-oxygen bonds bonded to silicon atoms on the silicon dioxide surface. They can also replace silicon atoms in the silicon dioxide structure.

  An anionic component is a component that does not alter the negative charge on the surface of the silicon dioxide powder, as measured as zeta potential, or is shifted to a more negative value.

  Stable means that the particles of silicon dioxide powder do not further agglomerate in the dispersion and the viscosity of the dispersion does not change or changes only slightly within a period of at least 1 week (less than 10% (Increased viscosity).

  Preferred cation donating compounds are amphoteric compounds having Be, Zn, Al, Pb, Fe or Ti as cations and mixtures of these compounds.

  Amphoteric compounds are those that act as bases for strong acids and acids for strong bases at the indicated pH values.

Particularly preferred cation donor compounds are aluminum compounds such as aluminum chloride, aluminum hydroxychloride of general formula Al (OH) _x Cl (x = 2-8), aluminum chlorate, aluminum sulfate, aluminum nitrate, general formula Al (OH ) Aluminum hydroxy nitrate of _x NO ₃ (x = 2-8), aluminum acetate, alums such as aluminum potassium sulfate or aluminum ammonium sulfate, aluminum formate, aluminum lactate, aluminum oxide, aluminum hydroxide acetate, aluminum Isopropylate, aluminum hydroxide, aluminum silicate and mixtures thereof. The aluminum silicate is, for example, Spernat 820 from Degussa AG, in which they are in the form of about 9.5 wt.% Aluminum as Al ₂ O ₃ , about 8 wt.% Sodium as Na ₂ O, or zeolite A. Is a particulate aluminum silicate containing sodium aluminum silicate.

  There are no restrictions on the type of silicon dioxide powder in the dispersion according to the invention. Accordingly, silicon dioxide powder produced by a sol-gel method, a sedimentation method or a thermal decomposition method can be used. This may be a metal oxide powder, wholly or partly cased in silicon dioxide, provided that its zeta potential is below 0 in the pH range 2-6.

  Silicon dioxide powder produced by a pyrolysis method is preferred.

  The pyrolysis method according to the present invention is a method in which one or more compounds containing silicon in the gas phase are flame hydrolyzed in a flame produced by the reaction of a combustion gas and an oxygen-containing gas, preferably air, It is understood to mean forming silicon dioxide. Suitable silicon-containing compounds are, for example, silicon tetrachloride, methyltrichlorosilane, ethyltrichlorosilane, propyltrichlorosilane, dimethyldichlorosilane, alkoxysilane and mixtures thereof. Silicon tetrachloride is particularly preferred. Suitable combustion gases are hydrogen, methane, ethane, propane, with hydrogen being particularly preferred. During flame hydrolysis, highly dispersible, non-porous primary particles are first formed, in which case they grow as the reaction proceeds to form aggregates, in which case they are further together To form a clot. The surface of the silicon dioxide particles produced pyrolytically has silanol groups (Si—H) and siloxane groups (Si—O—Si).

  Furthermore, the silicon dioxide powder produced by the pyrolysis method comprises doped silicon dioxide powder and silicon-metal mixed oxide powder produced by the pyrolysis method, provided that their zeta potential is in the range of pH 2-6. Or less.

  The production of doped powders is disclosed, for example, in DE-A-19650500. Typical doping components are, for example, aluminum, potassium, sodium or lithium. The content of the doping component generally does not exceed 1% by weight.

  Mixed oxide powder produced by pyrolysis means that both precursors of the mixed oxide are hydrolyzed together in a flame. Typical mixed oxide powders are silicon-aluminum mixed oxide or silicon-titanium mixed oxide.

According to a particularly preferred embodiment, the ratio of cation donor compound to silicon dioxide surface is preferably 0.0025 to 0.04 mg, in particular 0.005 to 0.02 mg of cation donor compound / m ² silicon dioxide surface.

The silicon dioxide surface corresponds to the specific surface area of the silicon dioxide powder measured by DIN 66131. Preferably the BET surface area in the range of ^{5~600m 2 / g, 30~400m 2 /} g, particularly preferably in the range of 50 to 300 m ² / g.

The pH value of the dispersion according to the invention is 2-6. Preferably it is 3 to 5.5. In particular, the BET specific surface area of silicon dioxide powder up to 50 m ² / g may be 3 to 4, the BET specific surface area of 50 to 100 m ² / g is 4 to 5, and 200 m ² / g. The BET specific surface area exceeding 4.5 is 5.5 to 5.5.

  If necessary, the pH value can be adjusted with acids or bases. Preferred acids are hydrochloric acid, sulfuric acid, nitric acid or carboxylic acid, for example acetic acid, oxalic acid or citric acid. Preferred bases are alkali hydroxides such as KOH or NaOH, ammonia, ammonium salts or amines. If necessary, the buffer system may be formed by adding salt.

According to a particularly preferred embodiment, at a shear energy of 1.28 S ⁻¹ , the viscosity of the dispersion according to the invention is compared to the viscosity of a dispersion having a similar composition but not containing a cation donor compound. It may be at least 10% lower. The viscosity is preferably 25%, in particular 50% lower, compared to that of a dispersion having a similar composition but not containing a cation donor compound.

  According to a particularly preferred embodiment, the number of agglomerates with a size of more than 1 μm in the dispersion according to the invention is greater than the number in dispersions having a similar composition but not containing a cation donor compound. Is at least 50% less. The number of agglomerates with a size of more than 1 μm is preferably 75%, in particular 90% less than a dispersion having a similar composition but not containing a cation donor compound.

  The dispersion according to the present invention may further contain a preservative. Suitable preservatives are, for example, benzyl alcohol, mono (poly) hemiformal, tetramethylol acetylene diurea, formamide monomethylol, trimethylol urea, N-hydroxymethylformamide, 2-bromo-2-nitropropane-1,3-diol, 1,6-dihydroxy-2,5-dioxahexane, chloromethylisothiazolinone, orthophenylphenol, chloroacetamide, sodium benzoate, octylisothiazolone, propiconazole, iodopropynylbutylcarbamate, methoxycarbonylaminobenzimidazole, 1, 3,5-triazine derivatives, methylisothiazolinone, benzisothiazolinone and their compounds.

The present invention further provides a method for producing a dispersion according to the present invention, wherein these methods comprise 0.001 to 0.1 mg cation donating silicon dioxide powder and at least one cation donating compound. The amount of compound / m ² silicon dioxide surface is contacted while moving in an aqueous solution.

  Contact while moving means, for example, stirring or dispersion. A dissolver, a gear disk, a rotor-starter machine, a ball mill or a mechanically stirred ball mill are suitable, for example, for dispersion. The high energy input may be a planetary kneader / mixer. However, the efficiency of this system depends on a mixture having a sufficiently high viscosity to introduce the high shear energy required for particle dispersion. The high pressure homogenizer can be used to obtain an aqueous dispersion containing aggregate sizes less than 200 nm in the dispersion.

  With these devices, at high pressure, at least two predispersed suspension systems are discharged through a nozzle. The two dispersion jets reliably collide with each other and the particles are crushed together. In other embodiments, the dispersion is further placed under high pressure, however, particle collision occurs around the wall. The operation is often repeated as it is preferable to obtain smaller particles.

  The process for producing the dispersion according to the invention can be carried out by adding the cation donor compound in the form of a solid or in the form of an aqueous solution to the aqueous dispersion of silicon dioxide.

  This can be done by adding the silicon dioxide powder to the aqueous solution of the cation donor compound at once or in small portions.

  Furthermore, it is possible to add the silicon dioxide powder and the cation donor compound simultaneously, batchwise or continuously to the liquid dispersed phase.

  In this case, “simultaneously” is understood to mean that the silicon dioxide powder and the cation donor compound may be premixed in the form of a physical or chemical mixture.

Furthermore, the present invention provides a powder of the type containing at least one cation donating compound and silicon dioxide powder, wherein the content of the cation donating compound calculated as an oxide is 0.001 to 0.1 mg. Cation donating compound / m ² silicon dioxide surface.

  Included in this are typical impurities of the starting material and impurities introduced during manufacture. The content of impurities is less than 1% by weight and usually less than 0.1% by weight.

  Preferably, the cation donor compound is an aluminum compound and the silicon dioxide is a silicon dioxide powder produced by a pyrolysis method.

  The powder according to the invention can be rapidly mixed in an aqueous medium.

  In the simplest method, it can be prepared by physically mixing silicon dioxide powder and at least one cation donor compound. Here, it is advantageous to use a separate package completely. Therefore, a homogeneous dispersion of silicon dioxide and cation donor compound is not essential.

  Furthermore, the powder according to the invention can be obtained by spraying at least one compound onto a silicon dioxide powder, in which case these compounds are soluble in the range of pH <6 or pH < It can be obtained by providing the cation by chemical reaction within the range of 6. The solution of the cation-feed compound can be sprayed continuously or batchwise in a dryer equipped with a heated mixer and spray device. Suitable equipment is, for example, a plow mixer, a disk dryer or a fluid bed dryer.

  The solution of the cation donor compound can be sprayed using an ultrasonic nozzle or can be atomized. The mixer can be heated in some cases.

  Furthermore, the powder according to the invention can be obtained by separating a cation donor compound, such as aluminum chloride, from the gas in a fluidized bed or mixer.

  Furthermore, the present invention provides water for chemical-mechanical polishing of metal surfaces, in particular for polishing copper surfaces, for the manufacture of ink jet paper, for gel batteries, for wine / fresh juice clarification / fining. To improve the stability and “blackness” of carbon black dispersions for ink-jet inks for improved suspension behavior of pigments and extenders and for increased scratch resistance with respect to base dispersion paints In addition, to stabilize emulsions and dispersions in the field of disinfectants, sol-gels for the production of latex / rubber products such as gloves, condoms, pacifiers or foamed rubber as reinforcing agents for natural and synthetic latex In order to remove surface viscosity (anti-blocking), To achieve non-slip effect in fine cardboard, to improve the slip resistance, for making the optical fiber, which is used to manufacture quartz glass.

  Surprisingly, the silicon dioxide dispersion in contact with the cation donor compound has good stability in the acidic range, while at the same time holding or enhancing the negative surface charge of the silicon dioxide particles. .

  This stabilization mechanism has not yet been explained. However, it is different from that disclosed in WO00 / 20221. Here, the charge of the silicon dioxide particles is completely reversed by the positively charged aluminum species, giving the particles a shell with a positive charge.

  Furthermore, it is different from that disclosed in US 2892797. Here, negatively charged metalate ions are mixed with the surface of the silicon dioxide particles. The particles thus modified are not very stable within the acidic pH range despite having a negative surface charge similar to the particles in the dispersion according to the invention.

Examples Analytical Methods Zeta potential was measured using Dispersion Technology Inc. , Measured by the CVI method.

The viscosity of the dispersion was measured using a Physica MCR 300 rotary rheometer and a CC27 female beaker, with the instrument being at 23 ° C. and a shear rate of 0.01 to 500 s ⁻¹ . The viscosity was obtained at a shear rate of 1.28 s- ¹ . This shear rate was performed in a range where the structural viscous action had a clear impact.

  Particle / agglomerate size was measured with a Horiba LB500 and LA300 instrument or with a Malvern Zetasizer 3000 Hsa.

The dispersion device used is, for example, a Dispermat AE-3M dissolver from VMA-GETZMAN with a dissolver disk diameter of 80 mm, or from IKA-WERKE with an S50N-G45G dispersion device. Ultra-Turrax T50 rotor / starter dispersion unit. If a rotor-starter device is used, the charged container is cooled to room temperature.

Furthermore, the dispersion can be carried out using a high energy mill. For each charge containing 50 kg of silicon dioxide powder, a portion of DI water is placed in a 60 l special steel charge vessel. A corresponding amount of aerosil powder was aspirated and roughly predispersed using a Ystrahl Conti-TDS3 dispersion and suction mixer. A pH value of 3.5 to -0.3 in the suction of the powder was maintained by addition of sodium hydroxide solution and aluminum chloride solution. After the powder was aspirated, the dispersion was completed with Conti TDS 3 (4 mm Stirrer slit width) at maximum speed using a sealed suction nozzle. Before the rotor / starter dispersion, the pH of the dispersion was set to pH 3.5 by adding more sodium hydroxide solution, and this was similarly maintained after dispersion for 15 minutes. By adding the residual amount of water, a SiO ₂ concentration of 20% by weight was set. This pre-dispersion was added to Sugino Machine Ltd. HJP-25050 Ultimateizer System from High Energy Mill with a pressure of 250 MPa and a diamond nozzle diameter of 0.3 mm and two lines passed through the mill.

Aerosil types 50, 90, 200 and 300 from the drug Degussa AG were used as silicon dioxide powder. AlCl ₃ in the hexahydrate form was used as the water-soluble aluminum compound. It was easily metered and homogenized using a 1% by weight solution with respect to Al ₂ O ₃ . The pH was adjusted using 1N NaOH solution or 1N HCl solution.

  In order to compare the viscosity of the dispersions, it was set to a uniform pH value of 3.5, possibly with the addition of 1N NaOH.

Dispersions Various loading sizes and properties of the resulting dispersions are shown in Tables 1 and 2.

Example 1a (reference example)
100 g Aerosil 50 (BET surface area about 50 m ² / g) was mixed in small portions into 385 g DI water using a dissolver set at about 1800 rpm. This resulted in a pH of 3.5. The remaining 15 g of DI water was then added to achieve a 20% dispersion, followed by dispersion at 2000 rpm for 15 minutes and dispersion at about 5000 rpm using an Ultra Turrax for 15 minutes.

Example 1b-g
100 g of Aerosil 50 was mixed in small portions into 385 g DI water and 1 wt% aluminum chloride solution (based on aluminum oxide) 1.25 g using a dissolver set at about 1800 rpm. This resulted in a pH of 3.4, in which case it was set to pH 3.5 by adding 0.7 g of 1N NaOH. The remaining 13.1 g of water was then added to achieve a 20% dispersion, which was then dispersed for 15 minutes at 2000 rpm and over 15 minutes using an Ultra Turrax at about 5000 rpm. And dispersed.

  Examples 1c-g were performed in the same manner as 1b.

Example 2a (reference example)
100 g of Aerosil 90 was mixed in small portions into 370 g of DI water using a dissolver set at about 1800 rpm and then dispersed at 2000 rpm for 15 minutes. The pH value was then set to 3.5 using 1N HCl and the dispersion was dispersed using an Ultra Turrax at approximately 5000 rpm for 15 minutes. The remaining water was then added to achieve a 20% by weight dispersion and the pH value was again set to 3.5.
Example 2b
Alternatively, 100 g of Aerosil 90 was mixed in small portions into 370 g of DI water using a dissolver set at about 1800 rpm and then dispersed at a setting of about 2000 rpm. Thereafter, 2.50 g of 1% by weight aluminum chloride solution (relative to aluminum oxide) was added, while being dispersed with an Ultra Turrax at about 5000 rpm and dispersed for 15 minutes. Thereafter, 26.3 g of DI water and 1.24 g of 1N NaOH were added to bring the 20% by mass dispersion to a pH value of 3.5.

Example 3a (reference example)
250 g DI water and 20 g 1% by weight aluminum chloride aqueous solution (relative to aluminum oxide) were provided. Aerosil 90 was added in small portions using a dissolver. The pH value was maintained at 3.5 during this process. After adding about 40 g of Aerosil 90 powder, the dispersion thickened very strongly and no further addition was possible.

Example 3b, 3c
Aerosil 90 100 g was mixed in 250 g DI water using a dissolver, and 10 g of 1% by weight aluminum chloride aqueous solution (based on aluminum oxide) and 1N NaOH were alternatively added little by little to obtain a pH value. Was 3.3 to 4.2. An additional 100 g of Aerosil 90 and an additional 10 g of 1% by weight aluminum chloride solution (based on aluminum oxide) and sufficient 1N NaOH are then added, alternatively, in small portions at 5000 rpm using an Ultra-Turrax. When the addition was completed, the pH value reached 3.5.

  The pH value of 4.0 was adjusted in Example 3c.

Example 4 (reference example)
Aerosil 90 50 g was mixed in small portions into 350 g DI water using a dissolver set at about 1800 rpm and then dispersed at 2000 rpm for 15 minutes. 100 g of 1% by weight aluminum chloride solution (relative to aluminum oxide) is added, while dispersed in Ultra Turrax at about 5000 rpm and dispersed for 15 minutes and pH value 2 is 30% hydroxylated The pH was increased to 3.5 using sodium solution.

Example 5
Example 5a was performed in a similar manner as 2a. Examples 5b-d were carried out in the same manner as 2b. For example, 5e-g increased about 100 ml of the dispersion of Example 5d by adding 30% sodium hydroxide solution dropwise to the pH values shown in Table 2, and over about 5 minutes, And homogenized, and the zeta potential of each was measured.

Example 6
Example 6a was performed in a similar manner as 2a. Examples 6b-d were carried out in the same manner as 2b.

FIG. 1 shows the zeta potential in mV (♦) and the viscosity in mPas (◯) of Examples 1a-g as a function of the Al ₂ O ₃ / m ² SiO ₂ -surface.

Example 7-Preparation of powder 500 g silicon dioxide powder (Aerosil 200, Degussa) was added to a 20 l Lodge mixer. At a spray power of about 100 ml / h, 20 g of 5% by weight aluminum chloride (relative to Al ₂ O ₃ ) was applied over a period of 10-15 minutes at a rate of 250 rpm. The powder has a 0.01 mg Al ₂ O ₃ / m ² silicon dioxide surface, a 202 m ² / g BET specific surface area and a bulk density of about 60 g / l. The moisture content may be about 4% and, if preferred, decreased by rotating the tube or fluidized bed by heating the wiper or subsequent drying in a drying cabinet. The aqueous dispersion (20% by weight) had a pH of 2.6.

^１）すべての試験において、３が２００ｇ、４が５０ｇであることを除き、それぞれＳｉＯ_２１００ｇであり、例１ Ａｅｒｏｓｉｌ５０、例２、３、４ Ａｅｒｏｓｉｌ９０、例５ Ａｅｒｏｓｉｌ２００、例６：Ａｅｒｏｓｉｌ３００は、すべてＤｅｇｕｓｓａＡＧからのものであった。
^２）ＡｌＣｌ_３として使用されたＡｌ_２Ｏ_３
^３）１Ｎ ＮａＯＨの代わりに１Ｎ ＨＣｌ
^４）３０％水酸化ナトリウム溶液
^５）３０％の水酸化ナトリウム溶液数滴を添加することにより、第２表中の相当するｐＨ値を達成した。

^{1) In} all tests, except that 3 is 200 g and 4 is 50 g, each is SiO ₂ 100 g, Example 1 Aerosil 50, Example 2, 3, 4 Aerosil 90, Example 5 Aerosil 200, Example 6: Aerosil 300 are all From Degussa AG.
²⁾ _Al ² _{O 3} was used as AlCl ₃
³⁾ 1N HCl instead of 1N NaOH
⁴⁾ 30% sodium hydroxide solution
⁵⁾ The corresponding pH values in Table 2 were achieved by adding a few drops of 30% sodium hydroxide solution.

^１）１週間後に測定した；
^２）１．２８Ｓ^−１の剪断力
^３）４０％分散液が製造できなかった
^４）ｎ．ｄ．＝測定せず
^５）ゲル化された分散液

¹⁾ measured after 1 week;
²⁾ Shear force of 1.28S ^-1
3) 40% dispersion could not be produced
⁴⁾ n. d. = Not measured
⁵⁾ Gelled dispersion

FIG. ₃ shows the zeta potential and viscosity of an aqueous dispersion according to the invention as a function of the Al ₂ O ₃ / m ² SiO ₂ -surface.

Claims (18)

The dispersion is stable in the range of pH 2-6,
The dispersion additionally contains at least one compound, in which case they are at least partially soluble in the form of polyvalent cations in aqueous solutions in the range of pH 2-6, Containing at least one compound that is stable in a silicate-like environment as an anionic component of the silicon dioxide particle surface;
The amount of cation donating compound relative to the silicon dioxide surface is 0.001 to 0.1 mg cation donating compound / m ² silicon dioxide surface, wherein the cation donating compound is calculated as an oxide, and ,
A silicon dioxide powder-containing aqueous dispersion having a silicon dioxide content of 10 to 60% by mass, wherein the dispersion has a zeta potential of 0 or less.   The aqueous dispersion according to claim 1, wherein the cation donor compound comprises an amphoteric compound having Be, Zn, Al, Pb, Fe or Ti as a cation and a mixture of these compounds.   The aqueous dispersion according to claim 2, wherein the amphoteric compound is an aluminum compound.   The aqueous dispersion according to any one of claims 1 to 3, wherein the silicon dioxide powder is a silicon dioxide powder produced by pyrolysis. The aqueous dispersion according to claim 4, wherein the BET specific surface area is 5 to 600 m ² / g.   The aqueous dispersion according to any one of claims 1 to 5, wherein the pH value is 3 to 5. Acid, preferably hydrochloric acid, sulfuric acid, nitric acid, C ₁ -C ₄ carboxylic acid or a base, preferably an alkali hydroxide, ammonia, an ammonium salt or an amine, is used to adjust the pH value, of claims 1-6 The aqueous dispersion according to any one of the above. 8. Aqueous dispersion according to any one of the preceding claims, wherein the viscosity at a shear energy of 1.28S- ¹ is at least 10% lower than the viscosity of a dispersion having a similar composition containing no cation donor compound. liquid.   9. Aqueous dispersion according to any one of the preceding claims, wherein the number of agglomerates with a size of more than 1 μm is at least 50% less than a dispersion having a similar composition containing no cation donor compound. .   The aqueous dispersion according to any one of claims 1 to 9, wherein the silicon dioxide powder has an average secondary particle size of less than 200 nm.   The aqueous dispersion according to any one of claims 1 to 10, comprising a preservative. And at least one cation donor compound with silicon dioxide powder, an amount of 0.001~0.1mg cation donor compound / m ² silicon dioxide surface is contacted while moving in an aqueous medium, from claims 1 to 11 A method for producing the aqueous dispersion according to any one of the above.   The method for producing an aqueous dispersion according to claim 12, wherein the cation-donating compound is added to the aqueous dispersion of silicon dioxide as a solid or an aqueous solution.   The method for producing an aqueous dispersion according to claim 12, wherein the silicon dioxide powder is added to the aqueous solution of the cation-donating compound at once or in small portions.   The method for producing an aqueous dispersion according to claim 12, wherein the silicon dioxide powder and the cation donating compound are added simultaneously, batchwise or continuously to the liquid dispersion phase. A powder comprising at least one cation donor compound and silicon dioxide powder, wherein the amount of cation donor compound calculated as oxide is 0.001 to 0.1 mg cation donor compound / m ² silicon dioxide surface.   The powder according to claim 16, wherein the cation-donating compound is an aluminum compound and the silicon dioxide is a silicon dioxide powder produced pyrolytically.   Metal surface chemical-mechanical polishing, especially copper surface polishing, inkjet paper manufacturing, gel battery, wine / fresh juice clarification / fining, improved suspension behavior of pigments and fillers in water-based dispersion paints and Natural latex and synthesis for increased scratch resistance, for improving the "blackness" stability of carbon black dispersions for inkjet inks, for stabilizing emulsions and dispersions in the field of disinfectants As a latex reinforcing agent, in the sol-gel field, to remove surface tackiness (anti-sticking agent), to achieve the anti-slip action of paper and cardboard, to produce optical fibers, and to produce quartz glass Use of the dispersion according to any one of claims 1 to 11.

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