JP2007277025A - Method for producing colloidal silica stable in acidity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing colloidal silica stable in acidity where dealkalization treatment with ion exchange resin is not required, and, further, in the case it is required, colloidal silica having high purity and stable in acidity can be easily and inexpensively produced. <P>SOLUTION: In the method for producing colloidal silica stable in acidity, colloidal silica and organic acid aluminum are mixed in such a manner that the colloidal silica expressed in terms of silica (SiO<SB>2</SB>) and the organic acid aluminum expressed in terms of alumina (Al<SB>2</SB>O<SB>3</SB>) satisfy the Al<SB>2</SB>O<SB>3</SB>/SiO<SB>2</SB>molar ratio of ≥5×10<SP>-7</SP>, and the mixture is subjected to heating treatment on the treatment condition that a heating temperature is ≥100°C and a heating time is ≥0.5 hr. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing acidic and stable colloidal silica, and in particular, acidic and stable colloidal silica that is less likely to cause aggregation or gelation in an acidic dispersion and can maintain a stable dispersion state for a long period of time. It relates to the manufacturing method.

  Colloidal silica is widely used in various applications such as abrasives, binders, physical property improvers, metal surface treatment agents, ground improvement injectants, etc. in many fields such as semiconductors, ceramics, paper, fibers, steel, and construction. It is a useful substance.

  And as a method of industrially producing this colloidal silica, a method of ion exchange of a sodium silicate aqueous solution, a thermal decomposition method of silicon tetrachloride, an organosilicate in a water-alcohol mixed solvent in the presence of an acidic or alkaline catalyst. A method of hydrolysis / condensation is proposed and implemented in the above, but colloidal silica is generally stable in an alkaline dispersion medium, and in an acidic dispersion medium, colloidal silica aggregates in a short time, As a result, there is a problem of lack of stability such as gelation.

  However, the fact that the dispersion medium of colloidal silica is limited to alkalinity significantly restricts the use of colloidal silica. For example, a polishing agent for mirror polishing of a silicon wafer in a manufacturing process of a semiconductor device, a titanium oxide photocatalyst, etc. In various applications such as binders mixed with organic solvents in hard coating applications, binders used in ceramic applications such as ceramic furnace materials and ceramic fibers, chromic metal surface treatment agents, ground improvement injecting agents, etc. There is a need for so-called acidic and stable colloidal silica that can be used stably in neutral or acidic dispersion media other than alkaline.

Thus, several proposals have been made regarding colloidal silica that can be used in such an acidic dispersion medium.
For example, JP-A-63-123,807 discloses an acidic silicic acid solution composed of an aqueous solution of polysilicic acid having a low degree of polymerization and an aluminum compound aqueous solution composed of an aqueous solution such as sodium aluminate and aluminum sulfate, and a silica-containing alkaline aqueous solution. Alternatively, an aluminum-containing alkaline silica sol obtained by adding to an alkali metal hydroxide aqueous solution, or an acid silicic acid solution mixed with an aluminum compound is added to a silica-containing alkali aqueous solution or alkali metal hydroxide aqueous solution. A method for producing an acidic silica sol by subjecting an aluminum-containing alkaline silica sol to dealkalization treatment with a cation exchange resin has been proposed.

In JP-A-6-199,515, (a) silica sol having a colloidal silica particle size of 4 to 30 mμm and a pH of 2 to 9 has an Al ₂ O ₃ / SiO ₂ molar ratio of 0. (B) The silica sol obtained in the step (a) is heated at 80 to 250 ° C. for 0.5 to 20 hours so that it exceeds 0006 but is 0.004 or less. And (c) by contacting the silica sol obtained in the step (b) with a cation exchange resin or a cation exchange resin and an anion exchange resin, thereby generating an acidic silica sol having a pH of 2 to 5. There has been proposed a method for producing a stable acidic silica sol having a colloidal silica particle size of 4 to 30 μm and a pH of 2 to 5.

  Further, JP-A-2005-162,533 discloses that colloidal silica obtained by hydrolyzing and condensing a hydrolyzable silicon compound is modified with a modifying agent such as a silane coupling agent, thereby providing an acidic dispersion medium. Even if it exists, the method of manufacturing the modified colloidal silica which can be stably disperse | distributed for a long period of time without causing aggregation and gelation of colloidal silica is proposed.

  However, in the methods described in JP-A-63-123,807 and JP-A-6-199,515, it is necessary to once prepare an alkali compound-containing alkaline silica sol and then dealkalize with an ion exchange resin. In addition, the production cost is high, and there is a limit of contamination by ion exchange resin and ion removal by ion exchange during dealkalization treatment. For example, high purity colloidal silica required for applications such as abrasives for semiconductor production in recent years There is a problem that it is not suitable for manufacturing. Further, in the method described in JP-A-2005-162,533, since the surface of the resulting colloidal silica is modified with a modifying agent such as a silane coupling agent, for example, when an organic modifying agent is used, It may not be suitable for applications such as materials where colloidal silica remains due to its weakness to ultraviolet rays, and may be unsuitable for applications such as semiconductor abrasives and high-purity ceramics due to contamination from modifiers. There is a problem.

JP 63-123,807 A JP-A-6-199,515 JP 2005-162,533 public

  Therefore, the present inventors do not need dealkalization treatment with an ion exchange resin and can produce it at low cost, and if necessary, easily and inexpensively produce high-purity acidic and stable colloidal silica. As a result of diligent investigations on the production method of acidic and stable colloidal silica that can be used, it is necessary to remove alkali with an ion-exchange resin by adding organic acid aluminum to colloidal silica at a predetermined ratio and heat-treating under predetermined conditions. In addition, it was found that high-purity acidic and stable colloidal silica can be easily and inexpensively produced when necessary, and the present invention has been completed.

  Accordingly, an object of the present invention is to eliminate the need for dealkalizing treatment with an ion exchange resin, and when necessary, it is possible to easily and inexpensively produce colloidal silica having high purity, acidity and stability. And to provide a stable method for producing colloidal silica.

That is, the present invention relates to colloidal silica and organic acid aluminum, colloidal silica converted to silica (SiO ₂ ), and organic acid aluminum converted to alumina (Al ₂ O ₃ ), Al ₂ O ₃ / SiO _{2. 2. A} method for producing acidic and stable colloidal silica, comprising mixing at a molar ratio of 5 × 10 ⁻⁷ or more, and subjecting the mixture to heat treatment at a treatment temperature of 100 ° C. or more and a heating time of 0.5 hour or more. It is.

  In the present invention, colloidal silica used as a raw material is a method of ion exchange of a sodium silicate aqueous solution, a thermal decomposition method of silicon tetrachloride, and an organosilicate is hydrolyzed in a water-alcohol mixed solvent in the presence of an acidic or alkaline catalyst. Any method such as a condensation method may be used. From the viewpoint of producing high-purity acidic and stable silica, it is preferable to use organosilicate in the presence of a hydrolysis catalyst. From the viewpoint of producing highly pure acidic and stable silica, it is more preferable to use organosilicate or hydrous having a metal impurity concentration of 1 ppm or less. It is good that it is colloidal silica manufactured using a decomposition catalyst and pure water.

  Here, regarding the metal impurities in question, specifically, sodium (Na), iron (Fe), copper (Cu), aluminum (Al), potassium (K), chromium (Cr), nickel (Ni), Lead (Pb), Manganese (Mn), Magnesium (Mg), Zinc (Zn), Calcium (Ca), etc., each of which should be 1 ppm or less, preferably 0.1 ppm or less, more preferably Is preferably 10 ppb or less. If the content of this metal impurity exceeds 0.1 ppm, for example, it is not suitable for uses such as high-purity semiconductor materials, and its use is limited.

In the present invention, the organosilicate is not particularly limited, but preferably the following general formula (1)
HxRySi (OR) z (1)
(In the formula, R represents a hydrocarbon group having 1 to 8 carbon atoms, which may be the same or different, and x, y, and z are any integers of 0 to 4. The total (x + y + z) represents an integer of 4).

  Here, in the general formula (1), specific examples of the compound where x = 0, y = 0, and z = 4 include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, and tetraphenoxysilane. And dimethoxydiethoxysilane.

  In addition, in the general formula (1), as the compounds of x = 0, y = 1 and z = 3, specifically, vinyltrimethoxysilane, epoxytrimethoxysilane, allyltrimethoxysilane, 3-butenyltri Methoxysilane, methacryloxytrimethoxysilane, methacryloxymethyltrimethoxysilane, acryloxyethoxytrimethoxysilane, acryloxypropyltrimethoxysilane, allylaminopropyltrimethoxysilane, vinyltriethoxysilane, epoxytriethoxysilane, allyl Triethoxysilane, 3-butenyltriethoxysilane, methacryloxytriethoxysilane, methacryloxymethyltriethoxysilane, acryloxyethoxytriethoxysilane, acryloxypropyltriethoxysilane, etc. Propoxy silane, epoxy tripropoxy silane, allyl tripropoxy silane, 3-butenyl tripropoxy silane, methacryloxy tripropoxy silane, etc., vinyl tributoxy silane, epoxy tributoxy silane, allyl tributoxy silane, 3-butenyl tributoxy Silane, methacryloxytributoxysilane, etc., isobutyltrimethoxysilane, isobutyltriethoxysilane, 3-isocyanatopropyltriethoxysilane, etc., N-methylaminopropyltrimethoxysilane, aminobutyltrimethoxysilane, aminobutyltriethoxy Silane, aminotripropoxysilane, aminotributoxysilane, etc., mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, mercaptomethyltripropoxy Silane, mercaptomethyltributoxysilane, mercaptoethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, etc., acetoxymethyltrimethoxysilane, acetoxyethyltrimethoxysilane, acetoxypropyltrimethoxysilane, etc. Acetoxymethyltriethoxysilane, acetoxyethyltriethoxysilane, etc., N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 6-azidosulfonylhexyltriethoxysilane, N-methylaminopropyltrimethoxysilane and the like can be mentioned.

  Further, in the general formula (1), as the compounds of x = 1, y = 0 and z = 3, specifically, trimethoxysilane, triethoxysilane, tripropoxysilane, tributoxysilane, triphenoxysilane, etc. Specific examples of the compound where x = 2, y = 0 and z = 2 include dimethoxysilane, diethoxysilane, dipropoxysilane, dibutoxysilane, diphenoxysilane and the like. Further, as compounds of x = 0, y = 2 and z = 2, specifically, acetoxymethylmethyldimethoxysilane, acetoxyethyldimethoxysilane, acryloxypropylmethyldimethoxysilane, N- (2- Aminoethyl) -3-aminoisobutylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane , 3-aminopropylmethyldiethoxysilane, bis (3-cyanopropyl) dimethoxysilane, isobutylmethyldimethoxysilane, mercaptomethylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, N-methylaminopropylmethyldimethoxysilane, etc. Can be mentioned.

  In the tetraalkoxysilanes represented by the general formula (1), the substituent R is preferably a lower alkyl group having 1 to 8 carbon atoms, more preferably a lower alkyl group having 1 to 4 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, and a hexyl group, and tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane are particularly preferable. Can be mentioned. Moreover, about these tetraalkoxysilanes, only 1 type can be used independently, it can also be used as a 2 or more types of mixture, Furthermore, it uses as a low condensate obtained by partially hydrolyzing. You can also

  As the hydrolysis catalyst, for example, alkali metal hydroxides such as sodium (Na) and potassium (K), ammonia catalysts such as ammonia and ammonium chloride, organic amines, quaternary ammonium compounds and the like are used. In the case of semiconductor applications where it is necessary to prevent metal contamination as much as possible, it is preferable to use an ammonia catalyst, organic amines, quaternary ammonium compounds and the like. As for this hydrolysis catalyst, only one of them can be used alone, and if necessary, it can be used as a mixture of two or more.

  Here, examples of the organic amines include various primary amines, secondary amines, and tertiary amines. Specific examples include methylamine, ethylamine, propylamine, butylamine, pentylamine, and hexyl. Amine, pentylamine, octylamine, nonylamine, decylamine, N, N-dimethylamine, N, N-diethylamine, N, N-dipropylamine, N, N-dibutylamine, trimethylamine, triethylamine, tripropylamine, tributylamine , Cyclohexylamine, trimethylimidine, 1-amino-3-methylbutane, dimethylglycine, 3-amino-3-methylamine, ammonia pyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, monoethanolamine, diethanolamine, dimethylmonoethanol Amine, monomethyl diethanolamine, triethanolamine, diazabicyclooctane, diazabicyclononane, it can be exemplified diazabicycloundecene or the like.

  Specific examples of the quaternary ammonium compounds include tetramethylammonium hydride (TMAH), trimethylhydroxyethylammonium hydride (choline), methyltrihydroxyethylammonium hydride, dimethyldihydroxyethylammonium hydride, and tetraethylammonium. Examples thereof include hydride, trimethylethylammonium hydride, tetrapropylammonium hydride, and tetrabutylammonium hydride.

  Furthermore, the colloidal silica used as a raw material in the present invention preferably has a solid content concentration of 10% by mass or more, more preferably 20% by mass or more, and an average particle size of 5 nm to 500 nm, preferably 5 nm or more. It should be 300 nm or less. When the solid content concentration of the colloidal silica is 10% by mass or more, there is an advantage that the transportation cost can be kept low, and even if this colloidal silica is mixed with other substances, a certain high concentration can be maintained. On the other hand, if the average particle size of colloidal silica is smaller than 5 nm, it is difficult to exist as particles. Conversely, if it is larger than 300 nm, dispersion stability may be lowered and sedimentation may occur.

  The organic acid aluminum used in the present invention is not particularly limited as long as it is available or manufacturable, but any organic acid aluminum that dissolves in colloidal silica may be used. It is preferable that it is a hydroxyl group-containing organic acid aluminum having one or two or more hydroxyl groups, and aluminum lactate is more preferable from the viewpoint of non-foaming property, odorlessness, purity, economy, and the like.

The use amount for the colloidal silica of the organic acid aluminum, silica Al ₂ O ₃ / SiO ₂ molar ratio of the organic aluminum which is converted to the converted the colloidal silica and alumina (Al ₂ O ₃₎ (SiO ₂₎ It needs to be 5 × 10 ⁻⁷ or more, preferably within a range of Al ₂ O ₃ / SiO ₂ molar ratio of 5 × 10 ⁻⁷ or more and 2 × 10 ⁻³ or less. If the amount of the organic acid aluminum used relative to the colloidal silica is lower than the Al ₂ O ₃ / SiO ₂ molar ratio of 5 × 10 ⁻⁷ , the stability of the liquid in the acidic region becomes worse, and conversely, Al ₂ O ₃ / SiO ₂ If the molar ratio is higher than 2 × 10 ^−3, the stability of the liquid in the acidic region is lowered, and the viscosity may increase to cause gelation.

  In the present invention, the above-mentioned colloidal silica is added with the above organic acid aluminum, and heat-treated at a heating temperature of 100 ° C. or higher and a heating time of 0.5 hour or longer, preferably 1 hour or longer to produce an acidic and stable silica. To manufacture. In this heat treatment, when the heating temperature is lower than 100 ° C., the viscosity may be increased and gelled when the liquid is acidified, and when the heating time is less than 0.5 hours, the liquid is acidified. In some cases, the viscosity increases and gelation occurs.

  The acidic and stable colloidal silica produced in this manner is stable without causing aggregation or gelation even if it is acidic while maintaining the particle diameter of the raw material colloidal silica. For example, the 6 mPa · s colloidal silica obtained in Example 1 of the present invention can be stored at 60 ° C. for 1 month at pH 8 or adjusted to acidic pH 3 and stored at 60 ° C. for 1 month. No change in viscosity is observed with 6 mPa · s.

  The acidic and stable colloidal silica produced in this way is used as acidic and stable abrasive grains in an acidic abrasive composition. In other words, the acidic copper wiring abrasive composition has properties of abrasive grains with excellent stability that do not cause aggregation or gelation even when coexisting with other acids. The present invention is very suitable when a polishing composition containing an organic acid such as quinaldic acid or lactic acid and having an acidity of around pH 2 to 5 is prepared as in the examples of JP-A-2000-183,003. ing.

  According to the method for producing an acidic and stable silica of the present invention, it can be produced at low cost without the need for dealkalization treatment with an ion exchange resin, and a high-purity production raw material to be used can be easily and inexpensively produced. Therefore, if necessary, high-purity acidic and stable silica can be easily and inexpensively produced.

Hereinafter, based on an Example and a comparative example, embodiment of this invention is described concretely.
[Example 1]
[Production of raw material colloidal silica]
In a 5 L glass reaction vessel equipped with a stirrer, thermometer, condenser distillation tube and organosilicate introduction tube, 539.4 g of pure water, 2,922 g of methanol, and 122.6 g of 28 mass% -ammonia aqueous solution. Then, while maintaining the solution in the reaction vessel at 23 ° C., 686 g of tetramethyl silicate (normal methyl silicate manufactured by Tama Chemical Co., Ltd.) was continuously fed into the solution over 2 hours with stirring. Hydrolysis and condensation reaction of tetramethyl silicate was performed.

  For the tetramethyl silicate, pure water, methanol, and aqueous ammonia solution used for the hydrolysis / condensation reaction of this tetramethyl silicate, the metal impurity concentration measured using an atomic absorption spectrophotometer is such that tetramethyl silicate is Na <4 ppb. Fe <6ppb, Cu <6ppb, Al <6ppb, K <4ppb, Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg <4ppb, Zn <4ppb, and Ca <4ppb, pure Water is Na <4ppb, Fe <6ppb, Cu <6ppb, Al <6ppb, K <4ppb, Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg <4ppb, Zn <4ppb, and Ca <4ppb And methanol is Na <4ppb, Fe <6ppb, Cu <6ppb, Al <6ppb, K <4ppb, Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg <4ppb, Zn <4ppb, And Ca <4 ppb, and aqueous ammonia solution is Na <4 ppb, Fe <6 ppb, Cu <6 ppb, Al <6 ppb, K < ppb, was Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg <4ppb, Zn <4ppb, and Ca <4 ppb.

After completion of the hydrolysis / condensation reaction, the reaction mixture obtained by allowing to cool is heated to 100 ° C., and methanol and water are distilled from the distillation tube to concentrate the reaction mixture in the reaction vessel to 1,400 g. And colloidal silica used as a raw material was prepared. The obtained raw material colloidal silica has a SiO ₂ concentration of 21.5% by mass, a pH of 9.70, a viscosity of 3.2 mPa · s, an average particle diameter determined by a photon correlation method of 54.5 nm, Metal impurity concentration (measured by atomic absorption spectrophotometer) is Na <4ppb, Fe <6ppb, Cu <6ppb, Al <6ppb, K <4ppb, Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg < 4 ppb, Zn <4 ppb, and Ca <4 ppb.

In a 1 L glass reaction vessel equipped with a stirrer, thermometer, condenser distillation tube and organosilicate introduction tube, the above raw material colloidal silica and aluminum lactate [metal impurity concentration (atomic absorption spectrophotometer measured value): Na < 4ppb, Fe <6ppb, Cu <6ppb, Al <6ppb, K <4ppb, Cr <10ppb, Ni <10ppb, Pb <6ppb, Mn <4ppb, Mg <4ppb, Zn <4ppb, and Ca <4ppb] The mixture was charged so as to have an Al ₂ O ₃ / SiO ₂ molar ratio shown in Table 1, heated and refluxed (heat treatment) under the treatment conditions of heating temperature and heating time shown in Table 1, and allowed to cool to Examples 1, 4 and 5 acidic colloidal silica was obtained.

[Example 2]
Methanol and water were distilled from the distillation tube, and the reaction mixture in the reaction vessel was concentrated to 1,450 g. The SiO ₂ concentration was 20.0% by mass, pH was 9.61, and the viscosity was 1.9 mPa · s. The acidic colloidal silica of Example 2 was obtained in the same manner as in Example 1 except that the raw material colloidal silica having an average particle diameter of 52.3 nm determined by the photon correlation method was used.

Example 3
Methanol and water were distilled from the distillation tube, and the reaction mixture in the reaction vessel was concentrated to 1,450 g. The SiO ₂ concentration was 19.9% by mass, pH was 9.56, and the viscosity was 4.6 mPa · s. The acidic colloidal silica of Example 3 was obtained in the same manner as in Example 1 except that the raw material colloidal silica having an average particle size of 53.5 nm determined by the photon correlation method was used.

For the acidic and stable colloidal silica obtained in each of Examples 1 to 5, the SiO ₂ concentration (mass%), pH, and viscosity (mPa · s) were measured, and the average particle diameter (nm) was determined by the photon correlation method. ) And metal impurity concentration (atomic absorption spectrophotometer measurement value) were measured.

The measurement results of the metal impurity concentration are the same as the raw material colloidal silica, and the metal impurity concentration (measured value by atomic absorption spectrophotometer) is Na <4 ppb, Fe <6 ppb, Cu <6 ppb, Al <6 ppb, K <4 ppb, Cr. <10 ppb, Ni <10 ppb, Pb <6 ppb, Mn <4 ppb, Mg <4 ppb, Zn <4 ppb, and Ca <4 ppb.
Other results are shown in Table 1.

  In addition, a predetermined amount of 3.6 mass% -hydrochloric acid was added to the acidic colloidal silica of each of Examples 1 to 5 to adjust the pH value shown in Table 1, and then transferred to a glass container, sealed, and sealed at 60 ° C. Conduct a "one month storage test" that is stored in a thermostat bath and measure the time to gelation, and measure the pH and viscosity (mPa · s) after one month for those that do not gel. did. The results are shown in Table 1.

[Comparative Example 1]
3.6 mass% -hydrochloric acid was added to the above raw material colloidal silica to adjust the pH value as shown in Table 1, and a 1 month storage test was conducted in the same manner as in Examples 1 to 5 above. Table 1 shows the properties observed after one month and the results of measured pH and viscosity (mPa · s).

[Comparative Examples 2 to 5]
In the above raw material colloidal silica, aluminum lactate was charged so as to have an Al ₂ O ₃ / SiO ₂ molar ratio shown in Table 1, then heat-treated under the conditions shown in Table 1, and then 3.6 mass% was added to the obtained acidic colloidal silica. -Hydrochloric acid was added to adjust to the pH value shown in Table 1, and a 1-month storage test was conducted in the same manner as in Examples 1 to 5 above. Table 1 shows the properties observed after one month and the results of measured pH and viscosity (mPa · s).

  According to the method for producing acidic and stable colloidal silica of the present invention, there is no need for dealkalization treatment with an ion exchange resin, and a high-purity production raw material can be easily and inexpensively obtained. Therefore, acidic and stable colloidal silica and, if necessary, high-purity acidic and stable silica can be easily and inexpensively produced, and have high industrial value.

Claims (7)

The colloidal silica and the organic acid aluminum, the colloidal silica converted to silica (SiO ₂ ), and the organic acid aluminum converted to alumina (Al ₂ O ₃ ) have an Al ₂ O ₃ / SiO ₂ molar ratio of 5 × 10. A process for producing acidic and stable colloidal silica, characterized in that the mixture is mixed so as to be ^-7 or more, and is heated under the treatment conditions of a heating temperature of 100 ° C or more and a heating time of 0.5 hours or more.   The method for producing acidic and stable colloidal silica according to claim 1, wherein the colloidal silica is colloidal silica obtained by hydrolyzing and condensing an organosilicate in the presence of a hydrolysis catalyst.   The method for producing acidic and stable colloidal silica according to claim 2, wherein the colloidal silica is colloidal silica produced using an organosilicate having a metal impurity concentration of 1 ppm or less, a hydrolysis catalyst, and pure water.   The method for producing acidic and stable colloidal silica according to claim 2 or 3, wherein the hydrolysis catalyst is an ammonia catalyst or an organic amine catalyst.   The method for producing acidic and stable colloidal silica according to any one of claims 1 to 4, wherein the colloidal silica has a solid content concentration of 20% by mass or more and an average particle diameter of 5 to 500 nm.   The method for producing acidic and stable colloidal silica according to any one of claims 1 to 5, wherein the organic acid aluminum is a hydroxyl group-containing organic acid aluminum having a hydroxyl group.   The method for producing acidic and stable colloidal silica according to claim 6, wherein the hydroxyl group-containing organic acid aluminum is aluminum lactate.