JPH09197705A - Organic-inorganic composite particles, their production and use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable stable production at a relatively high concn. by allowing a polymer having specified groups to exist in a process for polycondensing a hydrolyzate of a specified silicon compd. and/or its condensation product in the presence of a base. SOLUTION: At least one kind of hydrolyzable and condensable silicon compd. selected from among compds. represented by formula I and their derivs. is partially or entirely hydrolyzed in the presence of an acid and the resultant hydrolyzate and/or its condensation product is polycondensed in the presence of a base. At this time, a polymer having groups represented by formula II is allowed to exist in the hydrolyzing process and/or the polycondensing process. In the formulae, each of R<1> and R<2> is a 1-20C org. group, each of X and Y is a hydrolyzable group, (m) is an integer of 0-3, (n) is an integer of 0-2, in the case of m>=2, plural R<1> 's may different from each other, and in the case of 4-m>=2, plural X's may be different from each other.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to organic-inorganic composite particles, a method for producing the same, and uses thereof. More specifically, the present invention relates to organic-inorganic composite particles having excellent properties such as hardness, strength, elasticity and hydrophobicity, and a method for producing the same. Furthermore, the present invention relates to a method for producing organic-inorganic composite particles, by which fine particles can be efficiently obtained without causing aggregation even at a relatively high concentration. The present invention further provides an additive for toner which uses the organic-inorganic composite particles obtained by such a production method to improve properties such as charge stability and fluidity, and an electrostatic image development containing the additive. For toner for use.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic charge image is formed on the surface of a photoconductor, and a developer containing a toner charged to the opposite charge is brought into contact with the electrostatic charge image to remove the toner. Adhered to form a visible image. The visualized toner image is transferred to a transfer paper or the like, if necessary, and then fixed to form a copy.

As a method of charging the toner used in the development of such an electrostatic image, in the two-component developing method, a substance generally called a carrier is mixed and diffused to give the charge. Also in the one-component developing method, charging is performed by contact with a developing sleeve or a toner regulating blade. In either case, if the toner is not uniformly and stably charged, problems will occur during development and transfer. For example, there is a problem that the photosensitive surface is easily contaminated due to poor development image due to lack of scavenging effect of development image or lack of development electrode effect, or poor transferability of development image.

For the purpose of solving these problems, JP-A-52-135739 proposes a toner for developing an electrostatic charge image having a metal oxide powder or a silicon dioxide powder treated with aminosilane as a toner constituent. Has been done. Since this toner can maintain the positive charging characteristic, it is possible to improve the developing property and the transfer property. However, when these metal oxide powders or silicon dioxide powders are mixed with a binder resin for a toner and a colorant such as carbon black, it takes a long time to disperse them, and the manufactured toner particles are easily aggregated. Such a problem remained.

It is also known that hydrophobic colloidal silica is added to toner particles for the purpose of improving the fluidity and charging stability of the toner, and it has been put to practical use (for example, Japanese Examined Patent Publication No. 63-36499). Please refer to the number etc.). When such colloidal silica is added,
Although the fluidity is certainly improved, the dispersion at the time of production has a long life as described above, and the charging property of the toner is not sufficient. That is, the number of copies is 1
If the number of sheets exceeds 20,000, there is a problem that fog increases and image density decreases. This problem remarkably occurs when the temperature and humidity are high. Further, since such hydrophobic colloidal silica is quite hard, there is a problem that the surface of the photoreceptor is easily scratched during development.

[0006] It has also been proposed to add organic crosslinked particles such as crosslinked polymethylmethacrylate, crosslinked poly (styrene-methylmethacrylate), crosslinked poly (divinylbenzene) to the toner. Since it is relatively soft, there was a problem that carrier contamination occurs.

Further, none of these hydrophobic colloidal silica and organic crosslinked particles has a room for improvement because the fluidity and transfer efficiency of the toner cannot be sufficiently improved, and they have appropriate hardness as an additive for toner, and Hydrophobicity, that is, high corona charge retention, has been sought.

Further, Japanese Patent Laid-Open No. 63-101854 discloses that
A toner containing a polymethylsilsesquioxane powder having a negative charging characteristic is also disclosed in JP-A-63-101855.
JP-A No. 1993-242242 discloses a toner containing a polymethylsilsesquioxane powder having a positive charging property, which is surface-treated with an amino group-containing silane compound. Although this toner has good charging characteristics, the mechanical strength of polymethylsilsesquioxane is low, so that there is a problem in that the fluidity is lowered and the photosensitive surface is easily contaminated, resulting in poor transfer characteristics. It remained.

[0009]

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide novel organic-inorganic composite particles, a method for producing the same and uses thereof. The present invention also provides
Provided are organic-inorganic composite particles having excellent properties such as hardness, strength, elasticity and hydrophobicity, and a method for producing the same. A further object of the present invention is to provide a method for producing organic-inorganic composite particles, which enables efficient production of fine particles having the above-mentioned characteristics without causing aggregation even at a relatively high concentration. A further object of the present invention is to provide a toner additive capable of improving characteristics such as charge stability, fluidity, and transfer characteristics, and an electrostatic image developing toner containing the additive.

[0010]

[Means for Solving the Problems] The above-mentioned objects are represented by the following general formula (I):

[0011]

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(In the formula, R ¹ is a C _{1 to} C ₂₀ organic group, X is a hydrolyzable group, and m is an integer of 0 to 3. m is 2
In the above cases, a plurality of R ¹ may be the same or different, and when 4-m is 2 or more, a plurality of X may be the same or different. ), And at least one hydrolyzable / condensable silicon compound selected from the group consisting of compounds and derivatives thereof, is partially or completely hydrolyzed in the presence of an acid to give a hydrolyzate and / or a product thereof. A hydrolysis step of obtaining a condensate, and the hydrolysis product and / or
Alternatively, it has a polycondensation step of polycondensing the condensate thereof in the presence of a base, and in either or both of the hydrolysis step and the polycondensation step, the following general formula (II)

[0013]

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(Wherein R ² is a C _{1 to} C ₂₀ organic group, Y is a hydrolyzable group, and n is an integer of 0 to 2) and a polymer having a group is present. This is achieved by the method for producing organic-inorganic composite particles.

In the method for producing organic-inorganic composite particles of the present invention, the compounding ratio of the silicon compound and the polymer is preferably 0.1 to 100 parts by weight of the polymer with respect to 100 parts by weight of the silicon compound. . Further, in the general formula (I), the compound R ¹ Si having m = 1
A mixture of X ₃ and SiX ₄ 1 to 70 mol%, R
It is preferable that the ratio of ¹ SiX _{3 is} 99 to 30 mol%. Furthermore, in the method for producing organic-inorganic composite particles of the present invention, the polymer is at least one type of hydrolyzable / polymerizable compound selected from the group consisting of compounds represented by the following general formula (III) and derivatives thereof. It is desirable that the radical-polymerizable group-containing silicon compound is obtained by homopolymerization or copolymerization with an organic monomer capable of copolymerization.

[0016]

[Chemical 6]

(Wherein R ³ is a C ₂ -C ₂₀ organic group containing a radically polymerizable group, Y is a hydrolyzable group, and p = 1 to
An integer of 3, where p is 2 or more, C _{2 to} C in which at least one of a plurality of R ³ contains a radically polymerizable group.
₂₀ are organic groups, and the others are C _{1 to} C ₂₀ organic groups containing no radically polymerizable group. ) In the method for producing organic-inorganic composite particles of the present invention, it is desirable that the acid exhibit neutral surface activity by being neutralized. Further, the organic substance of the present invention
In the method for producing inorganic composite particles, it is preferable that the obtained organic-inorganic composite particles have an average particle diameter of 0.01 to 2 μm.

Further, the present invention is an organic-inorganic composite particle obtained by the above-mentioned production method. Further, the present invention is a toner additive comprising the organic-inorganic composite particles. Furthermore, the present invention is an electrostatic charge image developing toner containing the above-mentioned toner additive.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail based on embodiments. The silicon compound used in the method for producing organic-inorganic composite particles of the present invention has the general formula (I)

[0020]

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(In the formula, R ¹ is a C _{1 to} C ₂₀ organic group, X is a hydrolyzable group, and m is an integer of 0 to 3. m is 2
In the above cases, a plurality of R ¹ may be the same or different, and when 4-m is 2 or more, a plurality of X may be the same or different. ) At least one compound selected from the group consisting of compounds represented by

The compound represented by the general formula (I) used in the present invention has 1 to 4 hydrolyzable groups X. The hydrolyzable group X is a halogen atom, an alkoxy group, A monovalent group selected from an acyloxy group is preferable. These hydrolyzable groups are hydrolyzed by water,
It is used in the present invention because it is possible to form a polysiloxane by further condensation. Further, X in the general formula (I) is preferably a C _{1 to} C ₅ alkoxy group such as a methoxy group, an ethoxy group, a propoxy group and the like. When X is a C _{1 to} C ₅ alkoxy group, when the silicon compound is hydrolyzed and polycondensed,
This is because the compound produced as a by-product can be easily removed out of the system and hardly remains as an impurity.

R ¹ in the above general formula (I) is C ₁ to
It is a C ₂₀ organic group. As the organic group, a methyl group,
C ₁ -C ₂₀ alkyl groups such as ethyl group and propyl group; C ₁ such as phenyl group and methylphenyl group
To C ₂₀ aryl groups (including alkylaryl groups); further containing radically polymerizable groups such as acryloxyalkyl groups, methacryloxyalkyl groups, vinyl groups, isopropenyl groups, 1-alkenyl groups, or isoalkenyl groups. It includes such C ₂ -C ₂₀ which is formed by, or even they glycidoxy group, a mercapto group, which may have a substituent such as an amino group. Further, R ¹ is at least one selected from a C ₁ -C ₁₀ alkyl group which may have a substituent, an alkenyl group, and an aryl group, from the viewpoint that the hydrophobicity, that is, the corona charge retention rate can be increased. preferable.

When m in the general formula (I) is 2, two R ^1's may be different from each other or the same. When m is 3, three R ^1's may be different from each other, or two or more R ¹ 's may be the same. When 4-m is 2, two Xs may be different from each other or may be the same. When 4-m is 3, three Xs may be different from each other or two or more may be the same. When 4-m is 4, four Xs may be different from each other or two or more may be the same.

Specific examples of the compound represented by the general formula (I) used in the present invention are as follows. The compound represented by m = 0 in the general formula (I) is a tetraalkoxysilane compound such as tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane and dimethoxydiethoxysilane; Acyloxysilane compounds and the like.

The compound represented by m = 1 in the general formula (I) is methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, butyl. Trimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane,
3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane,
1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane , Methyltriacetoxysilane, phenyltriacetoxysilane, γ-methacryloxypropyltriacetoxysilane, and other organotrialkoxysilane compounds, organotriacyloxysilane compounds, and the like.

The compound represented by m = 2 in the above general formula (I) is dimethoxydimethylsilane, diethoxy-
3-glycidoxypropylmethylsilane, dimethoxydiphenylsilane, diacetoxydimethylsilane, diphenyldimethoxysilane, bis (γ-acryloxypropyl) dimethoxysilane, bis (γ-methacryloxypropyl) dimethoxysilane, γ-methacryloxypropylethyl Diorganodialkoxysilane compounds such as dimethoxysilane, γ-methacryloxypropylethyldiethoxysilane, γ-acryloxypropylethyldimethoxysilane, γ-acryloxypropylethyldiethoxysilane, dimethyldiacetoxysilane, and phenylmethyldiacetoxysilane. , Diorganodiacyloxysilane compounds and the like.

The compound represented by m = 3 in the above general formula (I) is trimethylmethoxysilane, trimethylethoxysilane, tris (γ-acryloxypropyl) methoxysilane, tris (γ-acryloxypropyl) ethoxysilane, tris. (Γ-methacryloxypropyl)
Methoxysilane, tris (γ-methacryloxypropyl) ethoxysilane, bis (γ-acryloxypropyl) vinylmethoxysilane, bis (γ-methacryloxypropyl) vinylmethoxysilane, γ-acryloxypropyldiethylmethoxysilane, γ-acryl Examples thereof include triorganoalkoxysilane compounds such as roxypropyldiethylethoxysilane, γ-methacryloxypropyldiethylmethoxysilane, γ-methacryloxypropyldiethylethoxysilane, and acetoxytrimethylsilane, and triorganoacyloxysilane compounds.

Derivatives of these compounds include, for example, a part of the X group of the compound represented by the general formula (I) is substituted with a β-dicarbonyl group and / or another group capable of forming a chelate compound. Examples thereof include compounds, low-condensates obtained by partially hydrolyzing and condensing compounds represented by the general formula (I) and / or chelate compounds thereof.

In the present invention, among these silicon compounds, the compound Si in which m = 0 in the above general formula (I) is used.
X ₄ and / or m = 1 in the above general formula (I)
It is desirable to mainly use the compound R ¹ SiX _{3 of the above,} and it is further essential that R ¹ SiX ₃ be essential to the organic-inorganic composite particles that can obtain desired properties such as hardness, mechanical strength and hydrophobicity. It is desirable from the viewpoint of imparting, and in particular, this silicon compound is a mixture of SiX ₄ and R ¹ SiX ₃ , and SiX _{4 is} 1 to 70 mol%, R ¹ SiX ₃ 9
It is preferably blended in a proportion of 9 to 30 mol%.

Among the silicon compounds represented by the general formula (I), the compound SiX _{4 with} m = 0 is particularly preferably tetramethoxysilane, tetraethoxysilane,
Alternatively, these are low-condensates of these, and the compound R ¹ SiX _{3 with} m = 1 is vinyltrimethoxysilane,
Examples thereof include vinyltriethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, and low condensation products thereof.

In order to obtain organic-inorganic composite particles having a positive charging characteristic, some or all of the silicon compound represented by the general formula (I) is used as R ¹
Is an amino group-containing organic group (when m is 2 or more, at least one is an amino group-containing organic group, and the other may be an organic group having no amino group).
It is preferable to use one. Examples of the amino group-containing silicon compound (A) include 3- (2-aminoethylaminopropyl) dimethoxydimethylsilane, 3-ureidopropyltriethoxysilane, 3-aminopropyltriethoxysilane, and 3-dimethylaminopropyl. Triethoxysilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, 3-aminopropyltrimethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 3-diethylaminopropyltrimethoxysilane, aminophenyltrimethoxysilane, N -Phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane and the like can be mentioned.

On the other hand, the following general formula (I
I)

[0034]

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(In the formula, R ² is a C _{1 to} C ₂₀ organic group, Y is a hydrolyzable group, and n is an integer of 0 to 2.) The polymer having a group is an organic polymer skeleton. The silicon atom bonded to has 1 to 3 hydrolyzable groups Y.
The group represented by the general formula (II) is preferably contained in the polymer in an amount of 2 or more, more preferably 3 or more, and further preferably 5 or more because the polymer is easily incorporated into the particles. preferable.

The hydrolyzable group Y is preferably a monovalent group selected from a halogen atom, an alkoxy group and an acyloxy group. These hydrolyzable groups can be hydrolyzed with water and further condensed to form a polysiloxane. Further, Y in the general formula (II) is a C _{1 to} C ₅ group such as a methoxy group, an ethoxy group, a propoxy group and the like, like X in the general formula (I).
It is desirable that it is an alkoxy group. Y is C _{1 to} C
_When the alkoxy group of ₅ is used, when the silicon compound described above and the polymer having the group represented by the general formula (II) are cohydrolyzed and polycondensed, the compound produced as a by-product can be easily removed to the outside of the system. This is because it is possible.

R ² in the general formula (II) is a C _{1 to} C ₂₀ organic group, similar to R ¹ in the general formula (I). The organic group may be a C _{1 to} C ₂₀ alkyl group such as a methyl group, an ethyl group or a propyl group;
A phenyl group, a methylphenyl group and the like and a C _{1 to} C ₂₀ aryl group (including an alkylaryl group); further, an acryloxyalkyl group, a methacryloxyalkyl group, a vinyl group, an isopropenyl group, a 1-alkenyl group, or iso C containing a radically polymerizable group such as an alkenyl group
_{2 to} C _{20 and the} like, which may further have a substituent such as a glycidoxy group, a mercapto group and an amino group.

When n in the general formula (II) is 2,
The two R ² may be different from each other or may be the same. When 3-n is 2, two Y's may be different from each other or may be the same. If 3-n is 3, then three Y's
May be different from each other, or two or more may be the same.

Further, the polymer having a group represented by the above general formula (II) has a molecular weight of the polymer as long as it has the group and contains an organic polymer skeleton.
Composition, backbone structure such as main chain, side chain, branched chain, cross-linked chain,
It is not limited to the presence or absence of a functional group. The organic polymer skeleton is, for example, at least one selected from poly (meth) acrylic acid ester, polystyrene, polyvinyl chloride, polyvinyl acetate, polyolefin and polyester.
One. A preferable organic polymer skeleton is a repeating unit-
Those having a main chain composed of C-C- (in the following,
Sometimes referred to as "vinyl-based polymer").

Further, as the polymer having the group represented by the general formula (II), the following general formula (III)
Obtained by copolymerizing at least one hydrolyzable / polymerizable radically polymerizable group-containing silicon compound selected from the group consisting of compounds represented by It is desirable that it is the one provided.

[0041]

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(Wherein R ³ is a C ₂ -C ₂₀ organic group containing a radically polymerizable group, Y is a hydrolyzable group, and p = 1 to
When p is 2 or more, one of a plurality of R ³ 's is a C _{2 to} C ₂₀ organic group containing a radically polymerizable group, and the other C's do not contain a radically polymerizable group. ₁ ~ C ₂₀
Is an organic group. The hydrolyzable group Y is the same as in the general formula (II).

R ³ in the above general formula (III) is
Acryloxyalkyl group, methacryloxyalkyl group,
A C _{2 to} C ₂₀ organic group containing a radically polymerizable group containing a radically polymerizable group such as a vinyl group, an isopropenyl group, a 1-alkenyl group, or an isoalkenyl group, but is preferably It is preferably one of the groups represented by the following general formula.

[0044]

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[0045]

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(Wherein R ⁴ is hydrogen or a methyl group,
R ⁵ is a C ₁ -C ₁₀ alkylene group. )

[0047]

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(Wherein R ⁶ is hydrogen or a methyl group,
R ⁷ is a phenylene group or a C ₁ -C ₁₀ alkylene group. In the above general formula (III), when p is 2 or more, one of a plurality of R ^{3 is} a C _{2 to} C ₂₀ organic group containing a radically polymerizable group, and the other is radically polymerizable. C ₁ -C ₂₀ organic groups not containing a group, for example, C ₁ -C ₂₀ alkyl groups such as methyl group, ethyl group, propyl group; phenyl group, methylphenyl group and C ₁ -C ₂₀ aryl group (Including an alkylaryl group). Further, these may have a substituent such as a glycidoxy group, a mercapto group and an amino group. When 4-p in the general formula (II) is 2 or more, a plurality of Y may be different from each other or may be the same.

Specific examples of the compound represented by the general formula (III) include vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltriacetoxysilane, γ-methacryloxypropylethyldimethoxysilane, γ-methacryloxypropylethyldiethoxysilane, γ-acryloxy Propylethyldimethoxysilane, γ-acryloxypropylethyldiethoxysilane, γ-acryloxypropyldiethylmethoxysilane, γ-acryloxypropyldiethylethoxysilane, γ-methacryloxypropyldiethylsilane Examples thereof include methoxysilane, γ-methacryloxypropyldiethylethoxysilane, 1-hexenyltrimethoxysilane, and 1-octenyltrimethoxysilane. Of these, particularly preferably, R ³ is the above general formula (a) or (b). , (C), and p = 1, specifically, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ- Methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane,
1-hexenyltrimethoxysilane and the like.

Further, the organic monomer copolymerizable with the hydrolyzable / condensable radically polymerizable group-containing silicon compound comprising the compound represented by the general formula (III) and its derivative is not particularly limited. Unsaturated carboxylic acids such as acrylic acid and methacrylic acid; acrylic acid esters, methacrylic acid esters,
Unsaturated carboxylic acid esters such as crotonic acid esters, itaconic acid esters, maleic acid esters and fumaric acid esters; acrylamides; methacrylamides; aromatic vinyl compounds such as styrene and α-styrene; vinyl acetate And vinyl compounds such as halogenated vinyl compounds such as vinyl chloride, and the like, and one or more of these may be used.
Of these, acrylic acid esters, methacrylic acid esters, aromatic vinyl compounds and vinyl esters are preferable.

In the case of copolymerizing with a silicon compound containing a radically polymerizable group capable of being hydrolyzed and condensed, which comprises a compound represented by the general formula (III) and a derivative thereof, the mixing ratio of the organic monomers is 1 to 50 mol% is suitable.

When it is desired to obtain organic-inorganic composite particles having a positive charging characteristic, a part or all of the polymer having a group represented by the general formula (II) may be used.
As in the case of the silicon compound (A), it is preferable to use one having a positively chargeable characteristic group such as an amino group and a ureido group in its skeleton.

Therefore, the method for producing the organic-inorganic composite particles of the present invention comprises at least one type of hydrolysis / condensation selected from the group consisting of the compound represented by the above general formula (I) and its derivatives. Hydrolyzate and / or hydrolysis of possible silicon compounds in the presence of acid
Or a hydrolysis step for obtaining the condensate, and a polycondensation step for polycondensing the hydrolyzate and / or the condensate thereof in the presence of a base, and either one of the hydrolysis step and the polycondensation step or A polymer having a group represented by the above general formula (II) is present in both of them.
As described above, in the present invention, since hydrolysis is performed in the presence of an acid, fine particles can be easily obtained without agglomeration in the hydrolysis step even at a high concentration.

Here, the blending ratio of the silicon compound and the polymer is 0.1 to 100 parts by weight of the polymer, more preferably 0.2 to 50 parts by weight, and further preferably 100 parts by weight of the silicon compound. 0.5-30
It is preferably a part by weight ratio. Polymer is 0.1
If it is less than 100 parts by weight, the mechanical strength of the obtained particles will not be sufficient, while if it exceeds 100 parts by weight, the obtained particles may aggregate.

The hydrolysis step of the first step is carried out as an aqueous solution by dissolving an acid serving as a catalyst in excess water. Examples of the acid catalyst used in the hydrolysis step include inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid and carbonic acid, formic acid, acetic acid, propionic acid, monochloroacetic acid, oxalic acid, citric acid, dodecylbenzenesulfonic acid, lauryl sulfate and lauric acid. Examples of the acid include organic acids such as stearic acid and p-toluene sulfonic acid. Among them, acids such as dodecylbenzene sulfonic acid, lauryl sulfuric acid, lauric acid and stearyl acid can be neutralized to increase the surface activity. It is desirable because it can be demonstrated. Note that strong acids such as dodecylbenzenesulfonic acid and laurylsulfate are preferable from the viewpoint of increasing the reaction rate of hydrolysis with a small amount and suppressing the partial condensation reaction of the hydrolyzate formed.

In addition, water or an organic solvent other than the acid catalyst may be present in the solvent. Specific examples of the organic solvent include methanol, ethanol, isopropanol, and n-.
Butanol, isobutanol, sec-butanol, t
-Alcohols such as butanol, pentanol, ethylene glycol, propylene glycol and 1,4-butanediol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; (cyclo) paraffins such as isooctane and cyclohexane; dioxane. , Ethers such as diethyl ether, and aromatic hydrocarbons such as benzene and toluene are used alone or in combination.

This hydrolysis step is carried out, for example, by using the above-mentioned silicon compound represented by the general formula (I) and a polymer having a group represented by the general formula (II) optionally added, or a solution thereof in an organic solvent. Is added to a medium containing water,
0 to 100 ° C, preferably 0 to 70 ° C for 30 minutes to
It is carried out by stirring for 100 hours. Further, in this hydrolysis step, the total concentration of the silicon compound represented by the general formula (I) and the polymer having the group represented by the general formula (II) which is optionally added is 10
-80 wt%, water concentration of 10-80 wt%, and acid catalyst concentration of 0.001-1 wt% are preferably used.

The polycondensation step of the second step is carried out in an aqueous solution of a base or a mixed solution of this and an organic solvent. In the second step, the combined use of an organic solvent suppresses agglomeration to form a fine composite. It is preferable in that body particles can be obtained. In the second step, an aqueous solution of a base or a mixed solution of the base and an organic solvent is charged into a reaction vessel, and then an aqueous solution of the hydrolyzate and / or a condensate thereof obtained in the first step, or This aqueous solution is further mixed with water and / or
Alternatively, a solution diluted with an organic solvent is added, and if necessary, a polymer having a group represented by the general formula (II) is added thereto to obtain the hydrolyzate obtained in the first step and / or its condensation. The condensation reaction is carried out by bringing the product (and the above-mentioned polymer added as necessary) into contact with a base. The method for adding the aqueous solution of the hydrolyzate and / or its condensate obtained in the first step to the aqueous solution of the base, the addition rate are not particularly limited, and the kind of the silicon compound used, the composition of the aqueous solution of the base, Especially, it is appropriately determined depending on the presence or absence of an organic solvent.

As the base catalyst used in the polycondensation step of polycondensing the hydrolyzate obtained in the hydrolysis step and / or its condensate, ammonia, urea,
Organic amines such as monomethylamine, dimethylamine and ethanolamine, and alkali metal or alkaline earth metal hydroxides such as tetramethylammonium hydroxide, sodium hydroxide, potassium hydroxide and lithium hydroxide can be used. However, among these, ammonia and organic amines are preferable because they do not leave a trace amount of impurities that limit the use of the obtained particles, and ammonia is particularly preferable because of low toxicity and easy removal.

In this polycondensation step, the water concentration is 10 to 99% by weight, and the base catalyst concentration is 0.01.
A range of 10 to 10% by weight and a reaction temperature of 0 to 50 ° C. are preferably used.

In this way, at least one hydrolyzable / condensable silicon compound selected from the group consisting of the compound represented by the general formula (I) or its derivative and the general formula (II) A polymer having a group represented is an organic-inorganic composite particle produced by cohydrolysis / polycondensation, which is conventionally known such as filtration, centrifugation, concentration under reduced pressure, spray drying, and instantaneous vacuum drying. After isolation from the slurry using the method and optionally washing, in air or in a nitrogen atmosphere at a temperature below 800 ° C., preferably 100 ° C.
To 600.degree. C., more preferably 150 to 500.degree. C., most preferably 200 to 450.degree. Organic-inorganic composite particles according to the present invention having specific strength and the like can be obtained.

The organic-inorganic composite particles thus obtained are polysiloxanes having an organic polymer skeleton and organic silicon in which at least one carbon atom in the organic polymer skeleton is directly bonded to a silicon atom in the molecule. It becomes an organic-inorganic composite particle including a skeleton.

The polysiloxane skeleton plays a role of increasing hardness of particles, and the organic polymer skeleton plays a role of increasing mechanical strength (breaking strength of particles). Since the particles have both a polysiloxane skeleton and an organic polymer skeleton, when the particles are used as an additive for a toner, for example, contamination of the photosensitive surface is suppressed and fluidity, transferability and the like are improved. Particularly, in the production method of the present invention, since the silicon compound represented by the general formula (I) is used in combination with the polymer having the group represented by the general formula (II), elasticity, mechanical strength, hydrophobicity It is expected that more excellent improvement of the properties will be achieved.

On the other hand, in a toner using particles having only a polysiloxane skeleton, for example, polymethylsilsesquioxane particles, since the mechanical strength is small, the photosensitive surface is apt to be contaminated, and conversely the fluidity and transferability are deteriorated. To do. Further, in a toner using particles having only an organic polymer skeleton, for example, polymethylmethacrylate-based particles, since the hardness of the particles is low, the photosensitive surface is easily contaminated, and the fluidity and transferability are deteriorated. In addition, since the particles generally have a low charge retention rate, the charging characteristics of the obtained toner are unstable.

The organic polymer skeleton includes at least the main chain of the main chain / side chain / branched chain / crosslinked chain derived from the organic polymer, and the molecular weight, composition, structure, and functionality of the organic polymer. It is not limited to the presence or absence of a group.

The polysiloxane skeleton referred to in the present invention has the following formula

[0067]

Embedded image

A siloxane unit represented by the formula (3) is chemically bonded continuously to form a three-dimensional network.

In the organic-inorganic composite particles according to the present invention, the SiO constituting the polysiloxane skeleton is
₂ amount is 10% by weight or more, preferably 25 to 95% by weight,
More preferably, it is desired to be 30 to 85% by weight. The amount of SiO ₂ constituting the polysiloxane skeleton is 1
If it is less than 0% by weight, the charging property and the mechanical strength will not be sufficient, and the cleaning property of the electrostatic image developing toner containing the organic-inorganic composite particles may not be desired. This is because there is. Note that Si
When the amount of O ₂ is extremely large, for example, more than 95% by weight, it cannot be deformed by an external pressure and is easily cracked, and the charge amount is not stable or the charge retention rate is low. There is fear.

The shape of the organic-inorganic composite particles obtained in the present invention is preferably spherical. Furthermore, the average particle size of the organic-inorganic composite particles obtained in the present invention is in the range of 0.01 to 2 μm, more preferably 0.03.
˜1 μm, more preferably 0.05 to less than 0.5 μm. Average particle size 0.01μ
If it is extremely smaller than m, it easily aggregates.
This is because the fluidity of the toner may decrease, and if it is extremely larger than 2 μm, the fluidity of the toner may decrease.

As described above, the organic-inorganic composite obtained by cohydrolyzing and polycondensing the silicon compound represented by the general formula (I) and the polymer having the group represented by the general formula (II). The particles generally have negative charging characteristics (ie, unless the silicon compound and polymer having a positively charging characteristic group such as an amino group are used as described above). The organic-inorganic composite particles can be used as they are, for example, as additives for toners for charge control, fluidity imparting, etc., but treatment of hydroxyl groups remaining on the surface of the organic-inorganic composite particles. Further, in order to adjust the negative charge amount, a surface treatment can be further performed with a silicon compound such as organotrialkoxysilane or hexamethyldisilazane, a titanium compound such as tetrabutyl titanate, or a hydrolysis / condensation product thereof.

On the other hand, in order to obtain the organic-inorganic composite particles according to the present invention having a positive charging property, the silicon compound represented by the general formula (I) and / or the general formula ( It is conceivable to use, as a part or all of the polymer having a group represented by II), a polymer having a positively chargeable characteristic group such as an amino group.

Alternatively, co-hydrolysis /
It is also possible to post-treat the organic-inorganic composite particles obtained by polycondensation with a surface treatment agent to impart positive charging characteristics. As the surface treatment agent, aluminum such as amino group-containing silane compound, aluminum ethylate, aluminum isopropylate, mono-sec-butoxyaluminum diisopropylate, aluminum-sec-butyrate, ethyl acetoacetate aluminum diisopropylate described above. Examples thereof include compounds and / or their partial hydrolysis / condensation products.

As a method of post-treating with the above-mentioned surface treatment agent, the surface of the organic-inorganic composite particles obtained by co-hydrolysis / polycondensation as described above is coated with the above-mentioned surface treatment agent. Any method may be used as long as it can be carried out. For example, the organic-inorganic composite particles are put into an appropriate container, and then the surface treatment agent is put, and then the mixture is stirred at room temperature (25 ° C.). ± 5 ° C) ~ 20
It can be performed by mixing and contacting at a temperature of about 0 ° C. for 10 minutes to 5 hours. In this case, the surface treatment agent can be an alcohol solution such as methanol and the like, and then the mixture can be gradually added dropwise to carry out mixing and contact for more uniform treatment. The amount of the surface-treating agent to be adsorbed on the surface of the organic-inorganic composite particles, the kind of the surface-treating agent and the processing time and the particle size of the organic-inorganic composite particles are appropriately selected depending on the charge amount to be imparted. It can be adjusted by selecting. After the surface treatment is performed in this manner, the object to be treated is washed with, for example, alcohol to remove unnecessary substances and obtain post-treated organic-inorganic composite particles.

The charge retention rate is preferably high, for example, when the composite particles are used as an additive for a toner, the charging property of the toner is improved. Specifically, the charge retention is determined by the measuring method described later. The charge retention rate after 5 minutes is 30
% Or more, preferably 40% or more, more preferably 50%
That is all.

The organic-inorganic composite particles obtained by the production method of the present invention can be used, for example, as an additive for a toner for developing an electrostatic image. The toner contains an additive for toner consisting of the specific organic-inorganic composite particles thus obtained, and contains a binder resin agent and a colorant as a binder as essential components, In addition to the above, additives commonly used in ordinary toners, such as an anti-offset agent and a charge control agent, may be appropriately blended, if necessary. Further, when it is used as a one-component developer, magnetic fine particles are added as is well known. The average particle size of such toner is not particularly limited, but 1 to 25 μm, and more preferably 3 to 20 μm is suitable.

The content of the additive for toner comprising the organic-inorganic composite particles according to the present invention in such a toner is not particularly limited, but is, for example, 0.0
It is 1 to 20% by weight, preferably 0.03 to 10% by weight, and more preferably about 0.05 to 5% by weight. If the content is less than 0.01% by weight, the fluidity and transfer characteristics are poor, while if it exceeds 20% by weight, the characteristics such as fixability, transferability and fluidity deteriorate. With
This is because it becomes difficult to prepare the toner.

The method for producing the toner for developing an electrostatic image according to the present invention is not particularly limited as long as it contains the additive for toner obtained by the above procedure, and the pulverization method,
Various production methods such as suspension polymerization method and emulsion polymerization method can be used. Also, as a method of adding the additive for toner, it may be added inside the toner particles, so-called internal addition form, or may be added so as to be attached to or added to the surface portion of the toner particles, so-called external addition form. Good. However, in order to obtain a toner having good fluidity, transfer characteristics, and charging characteristics for a long period of time, the toner additive must be present on the surface of the toner particles. Transfer characteristics are improved.

Further, the binder resin agent and the colorant, the offset preventing agent and the magnetic fine particles which can be used in the toner for developing an electrostatic image according to the present invention are not particularly limited, and in the field of conventional toners. Various types used can be used. Therefore, as a binding resin agent, although not limited to the following,
For example, styrene-based polymers, (meth) acrylic acid or (meth) acrylic acid ester-based polymers, polyolefin-based polymers, polyester-based polymers, polyurethane-based polymers, polyamide-based polymers, epoxy-based polymers, etc. may be used alone or in combination. Used. As the colorant, carbon black, phthalocyanine-based pigments, azo-based pigments / dye, nigrosine-based dyes, extender pigments, etc. may be used alone or in combination, and as magnetic fine particles, strong particles of iron, cobalt, nickel, etc. may be used. Fine particles such as magnetic metal powder, magnetite, hematite, and ferrite are used. It should be noted that the colorant such as carbon black, which is surface-modified by a grafting treatment with a hydrophilic polymer or the like, is desired because high dispersibility in the toner particles can be obtained. Further, as the anti-offset agent, low molecular weight polyethylene, polyolefin wax such as polypropylene, paraffin wax, natural wax such as carnauba wax and the like can be used.

As described above, in the electrostatic developing toner according to the present invention, by adding the toner additive comprising the organic-inorganic composite particles, good fluidity,
It has a transfer characteristic and a charging characteristic, and can develop an electrostatic charge image formed on a photoconductor into a clear image without fog.

[0081]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. Incidentally, the average particle diameter in the examples, SiO ₂
The content and the corona charge decay were measured by the following methods.

Average particle size Particle size (X) of 100 arbitrary particles in an electron microscopic image
Was measured and determined by the following formula.

[0083]

[Equation 1]

SiO ₂ content 5 g of particles were precisely weighed and collected in a crucible, and the amount of residue after firing at 1000 ° C. in air was precisely weighed to determine the oxide content by gravimetric analysis.

Charge retention rate after 5 minutes of charging Japanese Patent Application No. 5-246835 or Japanese Patent Application No. 6-2206
It was determined by the following method using a corona charging characteristic measuring device based on the principle described in No. 58. The principle is also shown below.

(Principle) The charge retention rate 5 minutes after charging is a value measured by the apparatus shown in FIG. FIG.
As shown in FIG. 1, the corona charging characteristic measuring device 1 includes a measuring unit that charges the powder to be treated by corona discharge to detect the surface potential, a conveying unit that conveys the powder to be treated, and a control unit that controls this device. It has and. The components of the device 1 are mounted or housed in casings 2A, 2B, 2C, 2D.

The measuring unit is a high voltage adjusting slider
0, a neon transformer 11, a high-voltage display voltmeter 13, a corona discharge electrode 30, a surface potential detector 31, and a high-voltage diode 32.

The high voltage adjusting slidac 10 is electrically connected to the primary side (input side) of the neon transformer 11 (see FIG. 4). The slidac 10 is disposed inside the casing 2A located on the lower left side. The neon transformer 11 is disposed inside a casing 2B located on the upper left side.

When the voltage from the external power source is input to the primary side of the neon transformer 11 through the sliderac 10, a high voltage (for example, several kV) is boosted to the secondary side according to the transformation ratio of the transformer 11. Will output. The high-voltage display lamp 14 lights up when electric power is being input from the external power source, and the lamp 14 when there is no input from the external power source.
Turns off. When power is being output from the secondary side of the transformer 11, the high voltage display lamp 15 is turned on, and when there is no output from the secondary side, the lamp 15 is turned off. The lamps 14, 15 and the voltmeter 13 are provided on the front wall of the casing 2B. This front wall is an internal transformer 1
1 is not shown so that it can be seen. Voltmeter 13
The voltage value on the primary side of the neon transformer 11 is measured, and the value obtained by multiplying the voltage value on the primary side by the transformation ratio is displayed as the voltage value on the secondary side. The corona discharge voltage is
The value displayed by the voltmeter 13 is used to adjust with high accuracy with the slidac 10.

The corona discharge electrode 30 is installed in the central casing 2D of the apparatus 1 above the vicinity of the center of the traveling path so that the corona discharge electrode 30 discharges directly below.

The diode 32 is provided outside the upper wall of the casing 2D, and the diode 32A in the forward direction is provided.
And a diode 32B in the opposite direction, and one of the diodes is electrically connected between the corona discharge electrode 30 and the secondary side of the neon transformer 11 by a switch (not shown). I have. With this switch,
The polarity of the electric charge of the powder to be processed 22 is selected. When the diode 32A is connected, the powder 22 to be processed is positively charged. When the diode 32B is connected, the powder 22 to be processed is negatively charged.

The surface potential detector 31 is installed in the upper part of the casing 2D, near the one end of the traveling path, inside the casing 2D.
A vibrating electrode (not shown) is provided at this lower end. The surface potential detector 31 is connected to the powder 22 to be processed through the vibrating electrode.
Is measured indirectly.

The carrying section is composed of a carrying mechanism 20 provided in the approximate center of the apparatus. As shown in FIG. 2, the transfer mechanism 20 includes a transfer floor 27, a transfer table 24, a moving wire 26, a drive motor 28, and two rails 49, 50.
And

The transfer floor 27 is installed on the bottom surface inside the casing 2D. On the transfer floor 27, two rails 4
9, 50 are laid in parallel to form a runway.

The transfer table 24 has the upper surface on which the powder 22 to be treated is placed, and the wheels 24a attached to the lower surface reciprocally move on the track by rolling in the forward and reverse directions on the rails 49 and 50.

The moving wire 26 forms a closed loop that passes above and below the transfer floor 27, is attached to the transfer table 24, and passes over the runway and is hung on pulleys installed on both sides of the runway.

The drive motor 28 is attached to the upper wall of the casing 2A and moves the wire 26 back and forth.
The drive motor 28 is a stepping motor in this example, but an AC or DC servo motor is also applicable.

On the upper wall of the casing 2D at the upper end of the other end of the runway, an openable / closable take-out port 3 for placing the powder 22 to be treated on the carrying table 24 or for taking it out from the carrying table 24.
Is provided.

As shown in FIG. 3, the control section includes a control box 40, an outlet position detector 51, a corona discharge position detector 52, a measurement position detector 53, and a conveyance control circuit 5.
5, a discharge control circuit 56, and a surface potential detection circuit 57.

The control box 40 is disposed inside the casing 2C at the lower right of the apparatus 1, and applies a voltage to the power switch 41, the power lamp 42 for displaying the operating state of the power switch 41, and the corona discharge electrode 30. Switch 43 for high voltage, a display lamp 44 for displaying the operating state of the high voltage switch 43, an operation switch 45 operated when moving the carriage 24 to the right in the figure,
Indicator lamp 4 for displaying the operating state of the operation switch 45
6. An operation switch 47 for operating the transfer table 24 in the left direction in the figure is provided, and a display lamp 48 for displaying an operation state of the operation switch 47 is operated by an operator.

The outlet position detector 51 is a sensor provided beside the rail 49 (or 50) at the other end of the track,
A position detection signal is output when the carrier table 24 is located below the take-out port 3 (home position).

The corona discharge position detector 52 is a sensor provided beside the rail 49 (or 50) at the center of the track, and outputs a position detection signal when the carrier table 24 is located directly below the corona discharge electrode 30. .

The control section is divided into a transport control block 59, a discharge control block 60, and a measurement control block 61.

The transport control block 59 is a transport control circuit 55.
It has. The transfer control circuit 55 controls the rotation direction and the rotation speed of the drive motor 28 based on the transfer signal from the control box 40. The transport signal is output when the operation switch 45 or the operation switch 47 is operated to the ON side. The drive motor 28 moves the carrier 24 by moving the wire 26 according to the carrier signal.

The discharge control block 60 is a discharge control circuit 56.
It has. The discharge control circuit 56 outputs a corona discharge signal when the high voltage switch 43 is turned on to input a voltage to the primary side of the transformer 11 so that the corona discharge electrode 30
More corona discharge is output. In the discharge control circuit 56,
A position detection signal is input from the take-out position detector 51, the corona discharge position detector 52, and the surface potential measurement position detector 53. Discharge control circuit 56 that outputs a corona discharge signal
Stops the corona discharge only when the position detection signals from the detectors 51 and 53 are not input, and after the position detection signals are input from the detector 52 and then the position detection signals from the detector 52 are stopped. . For this reason, the corona discharge electrode 30 which is performing corona discharge stops corona discharge immediately after the carrier 24 has passed directly below the corona discharge electrode 30.

The measurement control block 61 includes a surface potential measurement position detector 53, a surface potential detection circuit 57, and a recorder 58. The surface potential detection circuit 57 detects the surface potential signal from the surface potential detector 31 on condition that the position detection signal from the detector 53 is input. The recorder 58 records the detected surface potential signal as a surface potential in a time series. This record is stored in detectors 51 and 52.
Is not input and the detector 5
3 is performed, that is, when the carrier 24 is at the position of the surface potential detector 31.

The corona charging characteristic measuring device as described above is
The charge retention rate is measured by operating as follows (see FIG. 4). First, the power switch 41 is turned on. The high voltage switch 43 and the transport switches 45 and 47 are turned off. After the take-out port 3 is opened and the to-be-processed powder 22 is placed on the carrier table 24 located below the take-out port 3, the take-out port 3 is closed and the operation switch 47 is operated to the ON side.
The transport control circuit 55 receives the transport signal output by the ON operation of the switch 47 and rotates the drive motor 28 in a predetermined direction. As a result, the moving wire 26 is driven to move the carrier table 24 to the left (see FIG. 4A), and the take-out position detector 51 stops outputting the position detection signal.

The carrier table 24, which has moved to the left side, passes under the corona discharge electrode 30 which is not corona discharged (see FIG. 4B), and the surface potential is detected as shown in FIG. 4C. Surface potential measurement position detector 5 when it reaches directly below the device 31
3 outputs a position detection signal, and no carrier signal is input to the carrier control circuit 55.
Automatically stops just below 1. At this time, the surface potential measurement position detector 53 outputs a position detection signal, the detectors 51 and 52 do not output position detection signals, and the surface potential detector 31 outputs a surface potential signal of the powder 22 to be processed. , A surface potential detection circuit 57 detects a surface potential signal. The recorder 58
The detected surface potential signal is recorded as the surface potential A (V) after molding. The moving time from the take-out position of the carrier table 24 to the surface potential measurement position is within 1 second.

After this recording is performed, the operator operates the operation switch 45 to the ON side. Transport control circuit 55
Receives the transport signal output by the ON operation of the switch 45 and rotates the drive motor 28 in a predetermined direction.
As a result, the moving wire 26 is driven to move the transfer table 24.
Moves to the right, and the surface potential measurement position detector 53 stops outputting a position detection signal. Transport platform 24 moved to the right
However, when it passes under the corona discharge electrode 30 which is not corona-discharged and reaches right under the take-out port 3 as shown in FIG. 4 (A), the take-out position detector 51 outputs a position detection signal. The carrier signal is no longer input to the carrier control circuit 55, and the carrier table 24 automatically stops immediately below the take-out port 3.

Next, the input voltage on the primary side is adjusted by the sliderac 10 so that the output voltage on the secondary side of the neon transformer 11 becomes 3.6 kV. Further, a forward diode 32A (or a reverse diode 32B) is electrically connected between the corona discharge electrode 30 and the secondary side of the neon transformer 11 by a switch (not shown). The polarity of the electric charge of the body 22 is selected, and the high voltage switch 43 is selected.
Is turned ON. After this operation is performed, when the operator operates the operation switch 47 to the ON side, the carrier 24 starts to move to the left. When the carrier 24 passes directly below the corona discharge electrode 30 that is corona-discharging (see FIG. 4B), the powder 22 to be treated passes through the corona discharge and is instantly charged to the selected polarity. To do. Only when the transfer table 24 passes directly below the corona discharge electrode 30, only the corona discharge position detector 52 outputs a position detection signal. Thereafter, the high voltage switch 43 is automatically turned off.
At F, the corona discharge ends.

The carrier table 24 which has passed directly below the corona discharge electrode 30 has the surface potential detector 3 as shown in FIG.
When it reaches directly below 1, the take-out position detector 51 and the corona discharge position detector 52 do not output the position detection signal, but only the surface potential measurement position detector 53 outputs the position detection signal. By the output of this position detection signal, the transport control circuit 55
The carrier signal is no longer input to the device and automatically stops right below the surface potential detector 31, and the surface potential detector 31 outputs the surface potential signal of the powder to be treated 22 detected via the vibrating electrode to detect the surface potential. The circuit 57 detects the surface potential signal, and the recorder 58 records the detected surface potential signal as the surface potential of the powder to be processed 22 in time series. The surface potential signal detected first is the surface potential B immediately after corona charging.
_The surface potential signal detected after ₁ (V) and 5 minutes is the surface potential B ₂ (V) 5 minutes after corona charging. The moving time of the carrier 24 from the take-out position to the surface potential measurement position is 1
Seconds.

After the above series of operations is completed, the operation switch 4 is used to move the carrier table 24 to the take-out position.
5 should be operated to the ON side.

Both the positive and negative charges can be applied to the powder to be treated, the corona discharge electrode and the surface potential detector are provided at a predetermined distance from each other, and they can operate simultaneously. Since it does not exist, it is possible to accurately measure the charging characteristics of the powder to be treated (state of change in surface potential with time, attenuation characteristics) without being affected by disturbances such as noise.

(Measurement method) Diameter 7.6 cm, depth 0.5
Into a metal cell of cm, a powder to be processed having a diameter of 5 cm and a height of 0.3 cm was put to flatten the upper surface of the molded body.
After standing still at 0 ° C. and 60% RH overnight, the metal cell was placed on a carrier and the above apparatus was used (the voltage applied to the corona discharge electrode during corona discharge was 3.6 kV and the powder to be treated was negative or negative). The diode was set so as to be positively charged.) Measured surface potential (A) after standing overnight for molding, surface potential (B ₁ ) immediately after corona charging, and surface potential 5 minutes after corona charging ( B ₂ ) is used to calculate the charge retention rate after 5 minutes of charging by the following formula. The measurement is also performed in an atmosphere of 20 ° C. and 60% RH.

[0115]

[Equation 2]

(Here, E is the charge retention rate (%) after 5 minutes of charging, Q ₁ is the charge amount after standing overnight for molding, Q ₂ is the charge amount immediately after corona charging, Q ₃ is the charge amount 5 minutes after corona charging, C is the capacitance of the powder to be treated, A is the surface potential (V) after standing overnight for molding, and B ₁ is the corona. The surface potential (V) immediately after charging,
B ₂ is the surface potential (V) 5 minutes after the corona charging. ).

Particle Grain Strength Evaluation Method 0.1 g of particles was mixed with 5 g of methanol and ultrasonically dispersed, and then one drop of the slurry was dropped onto a sample stage for a scanning electron microscope (SEM). Next, after heating at 90 ° C to evaporate the methanol, scratch the sample with a spatula and then SE
M was observed. When the particles scratched with a spatula were crushed into finer particles than the particles not scratched, it was considered that the particle strength was low (denoted by X in the table). When the crushed fine particles were not formed, it was considered that the particle strength was high (denoted by O in the table).

Example 1 γ-methacryloxypropyltrimethoxysilane 50
g, 50 g of methanol, 2, as a radical polymerization initiator
1 g of 2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) was mixed, and γ-methacryloxypropyltrimethoxysilane was polymerized in an N ₂ atmosphere at 60 ° C. for 4 hours. The solution obtained after the polymerization reaction was used as a polymer solution (1). The solid content of the polymer solution (1) was 49% (measured by vacuum drying at 150 ° C. for 4 hours), and the number average molecular weight was 13,000 (polystyrene conversion).
GPC analysis).

Next, 50 g of vinyltrimethoxysilane
(0.338 mol), tetramethoxysilane 10 g
(0.066 mol), 300 ppm of a 300 ppm aqueous solution of dodecylbenzene sulfonic acid and 5 g of the polymer solution obtained above (solid content 2.45 g) were mixed, and heated and stirred at 50 ° C. for 30 minutes to obtain a transparent solution. After cooling, 40 g of methanol was mixed with this solution to obtain a uniform transparent solution, which was designated as solution B.

On the other hand, 500 g of water and 10 g of 25% by weight ammonia solution were mixed to prepare a liquid A separately, and the liquid B was added dropwise over 2 hours while stirring the liquid A to carry out a polycondensation reaction. The resulting suspension was subjected to solid-liquid separation by filtration, and the obtained cake was washed with water and filtered repeatedly,
The composite particles (1) were obtained by firing at 250 ° C. for 2 hours under N ₂ atmosphere.

The average particle diameter of the obtained composite particles (1) was 0.58 μm, and the SiO ₂ content in the particles (1) was 76.0% by weight. When the corona charge decay of the particles (1) was measured, the charge retention rate after 5 minutes of charge was 81%. The particle strength of the particles was high.

Example 2 Solution B was prepared in the following manner instead of solution B in Example 1. 40g vinyltrimethoxysilane
(0.270 mol), γ-methacryloxypropyltrimethoxysilane 10 g (0.040 mol), tetramethoxysilane 5 g (0.033 mol) and 300 ppm.
Mix 45 g of dodecylbenzene sulfonic acid aqueous solution, and
A transparent solution was obtained by heating with stirring at 0 ° C. for 30 minutes. After cooling, 40 g of methanol and 10 g of the polymer solution (1) obtained in Example 1 (solid content 4.9 g) were mixed with this solution to obtain a uniform transparent solution, which was designated as solution B.

Then, in the same manner as in Example 1, solution B was added dropwise over 2 hours while stirring solution A to carry out a polycondensation reaction. The resulting suspension was subjected to solid-liquid separation by spray drying, crushed by jet mill crushing, and then composite particles (2) were obtained at 350 ° C. for 2 hours in a N ₂ atmosphere. Table 2 shows the analysis results of the obtained composite particles (2).

Example 3 100 g of vinyltrimethoxysilane and 5 g of benzoyl peroxide as a radical polymerization initiator were mixed and heated in an N ₂ atmosphere at 80 ° C. for 4 hours to polymerize vinyltrimethoxysilane. After the polymerization reaction, the obtained solution was used as a polymer solution (2). The solid content in this polymer solution was 15%, and the number average molecular weight was 1200.

Next, as a silicon compound, 50 g (0.338 mol) of vinyltrimethoxysilane, 5 g (0.033 mol) of tetramethoxysilane, 45 g of a 300 ppm aqueous solution of dodecylbenzenesulfonic acid and 5 g of the polymer solution (2) obtained above. (Solid content 0.75 g) is mixed,
Stir for 30 minutes at 50 ° C. to obtain a clear solution. After cooling,
40 g of methanol was mixed with this solution to obtain a uniform transparent solution, which was designated as solution B.

Then, in the same manner as in Example 2, solution B was added dropwise over 2 hours while stirring solution A to carry out a polycondensation reaction. The obtained suspension was subjected to solid-liquid separation by spray drying, crushed by crushing with a jet mill and further crushed to obtain composite particles (3) in a N ₂ atmosphere at 200 ° C. for 2 hours. Table 2 shows the analysis results of the obtained composite particles (3).

Examples 4 and 5 Instead of the polymer solution (2) used for preparing the solution B in Example 3, a polymer solution (3) as shown in Table 1 was used.
Liquid B was prepared using (4) and (4), and composite particles (4) and (5) were obtained in the same manner as in Example 3 except that the silicon compound shown in Table 1 was used. Table 2 shows the analysis results of the obtained composite particles (4) and (5).

Comparative Example 1 Comparative composite particles (6) were obtained in the same manner as in Example 3, except that the solution B was prepared without using the polymer solution. Table 2 shows the analysis results of the obtained composite particles for comparison (6).

Comparative Example 2 In Example 3, 50 g (0.338 mol) of vinyltrimethoxysilane, 5 g (0.033 mol) of tetramethoxysilane as the silicon compound, and the polymer solution (2)
5 g (solid content 0.75 g) was used, and methanol 4
A mixture of 0 g was used as solution B (the hydrolysis step with an aqueous solution of dodecylbenzenesulfonic acid was not performed). Then, in the same manner as in Example 3, the solution B was dropped while stirring the solution A, and when the solution B was dropped about 1/3 amount, terrible agglomeration occurred and stirring became impossible.

[0130]

[Table 1]

[0131]

[Table 2]

Example 6 To 100 g of a toner having an average particle size of 8 to 12 μm, in which carbon black as a coloring agent is dispersed in a binder resin agent made of a styrene-n-butyl acrylate copolymer,
1 g of the composite particles (1) was mixed using a Henschel mixer to obtain the toner (1) of the present invention.

When Toner (1) was placed in a commercially available copying machine and a continuous copying test was performed on 50,000 sheets, no fog was generated on the image. The charge amount at the initial stage and after copying 50,000 sheets is -28μ
C / g and -30 μC / g. Further, a good image was shown even in an environment of high temperature and high humidity (30 ° C., 85% RH). The charge amount at high temperature and high humidity was −26 μC / g. Further, the cleaning property of the toner remaining on the photosensitive surface was good, and neither scratches nor filming occurred on the photosensitive surface.

The charge amount of the toner obtained without mixing the composite particles (1) was −28 μC / g, and the charge amount of the toner was not changed by the mixing of the composite particles (1).
The toner in which the composite particles (1) were not mixed had poor fluidity, which caused clogging in the toner supply section of the copying machine, and also caused poor cleaning and scratches and filming on the photosensitive surface.

Examples 7 to 9 Toners (2) to (4) are obtained by using the composite particles (2) to (4) in place of the composite particles (1) in Example 6.
A continuous copying test was conducted. Table 3 shows the obtained results.

Example 10 Carbon black as a colorant and nigrosine as a charge control agent were dispersed in a binder resin agent made of a styrene-n-butyl acrylate copolymer, and an average particle diameter was 10 to 1.
Composite particles (5) for 100 g of 5 μm toner
A toner (5) was obtained and a continuous copying test was conducted in the same manner as in Example 6 except that 1 g was used. Table 3 shows the obtained results. The charge amount of the toner obtained without using the composite particles (5) was +20 μC / g.

Comparative Example 3 Example 6 was repeated except that polymethylsilsesquioxane powder (manufactured by Toshiba Silicone, Tospearl 103, average particle size 0.32 μm) was used instead of the composite particles (1) in Example 6. In the same manner as in (1), a toner (6) using polymethylsilsesquioxane powder was obtained and a continuous copying test was conducted. Table 3 shows the obtained results. Since the mechanical strength (breaking strength) of the polymethylsilsesquioxane powder is small, it is 0.
The particles were crushed into fine particles of less than 05 μm, causing fog, poor cleaning, scratches on the photosensitive surface, and filming.

Comparative Example 4 In Example 6, instead of the composite particles (1), hydrophobic colloidal silica (Aerosil R97 manufactured by Nippon Aerosil Co., Ltd.) was used.
2. Toner (7) using hydrophobic colloidal silica was obtained in the same manner as in Example 6 except that the average particle diameter was 0.016 μm), and the continuous copying test was conducted. Table 3 shows the obtained results.

Comparative Example 5 In the same manner as in Example 6 except that the composite particles for comparison (6) were used in place of the composite particles (1) in Example 6,
A toner (8) using the composite particles for comparison (6) was obtained, and a continuous copying test was conducted. Table 3 shows the obtained results. The mechanical strength (breaking strength) of the composite particles for comparison (6)
However, when mixed with a Henschel mixer, it was crushed into fine particles of less than 0.05 μm, causing fog, poor cleaning, scratches on the photosensitive surface, and filming.

[0140]

[Table 3]

[0141]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, at least one hydrolyzable / condensable silicon compound selected from the group consisting of the compounds represented by the general formula (I) and derivatives thereof is treated with an acid. And a polycondensation step of polycondensing the hydrolyzate and / or its condensate in the presence of a base to obtain a hydrolyzate and / or its condensate And a polymer having a group having a group represented by the general formula (II) is present in either or both of the hydrolysis step and the polycondensation step. Therefore, the organic-inorganic composite particles excellent in various properties such as hardness, mechanical strength, elasticity and hydrophobicity can be stably produced at a relatively high concentration. Further, by incorporating the organic-inorganic composite particles having such excellent properties into the toner particles as an additive for toner, an electrostatic charge image having a predetermined charge amount and a stable charge holding ratio for a long time is obtained. It is possible to provide a developing toner.

[Brief description of drawings]

FIG. 1 is a cross-sectional view schematically showing the configuration of a corona charging characteristic measuring device used for measuring a charge retention rate in an example of the present invention,

FIG. 2 is a plan view schematically showing a configuration of a transport mechanism of the corona charging characteristic measuring device,

FIG. 3 is a circuit diagram schematically showing a configuration of a control unit of the corona charging characteristic measuring device,

4A to 4C are plan views showing an operating state of the corona charging characteristic measuring device at the time of measuring the charge holding ratio.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Corona charging characteristic measuring device, 2A, 2B, 2C, 2D ... Casing, 3 ... Ejection port, 10 ... High voltage adjustment slidac, 11 ... Neon transformer, 13 ... High voltage display voltmeter, 20 ... Conveyance mechanism, 22 ... Powder to be treated, 24 ... Transport base, 26 ... Transfer wire, 27 ... Transport bed, 28 ... Drive motor, 30 ... Corona discharge electrode, 31 ... Surface potential detector, 32 ... High voltage diode, 40 ... Control box, 41 ... Power switch, 43 ... High voltage switch, 45, 47 ... Operation switch, 49, 50 ... Rail, 51 ... Ejection position detector, 52 ... Corona discharge position detector, 53 ... Surface potential measurement position Detector, 55 ... Transport control circuit, 56 ... Discharge control circuit, 57 ... Surface potential detection circuit, 58 ... Recorder, 59 ... Transport control block, 60 ... Discharge control Block, 61 ... Measurement control block.

Claims (9)

[Claims] 1. A compound represented by the following general formula (I): (In the formula, R ¹ is a C _{1 to} C ₂₀ organic group, X is a hydrolyzable group, and m is an integer of 0 to 3. When m is 2 or more, a plurality of R ^1's are the same. Which may be present or different, and when 4-m is 2 or more, a plurality of X may be the same or different, and at least one selected from the group consisting of compounds represented by Hydrolysis step of partially or wholly hydrolyzing one kind of hydrolyzable / condensable silicon compound in the presence of an acid to obtain a hydrolyzate and / or a condensate thereof, and the hydrolyzate and / or a condensation thereof Having a polycondensation step of polycondensing the product in the presence of a base,
In either or both of the hydrolysis step and the polycondensation step, the following general formula (II): (In the formula, R ² is a C _{1 to} C ₂₀ organic group, Y is a hydrolyzable group, and n is an integer of 0 to 2.) Organic-inorganic substance in which a polymer having a group represented by Method for producing composite particles. 2. The method for producing organic-inorganic composite particles according to claim 1, wherein the compounding ratio of the silicon compound and the polymer is 0.1 to 100 parts by weight of the polymer with respect to 100 parts by weight of the silicon compound. . 3. The silicon compound is a mixture of the compound SiX ₄ having m = 0 in the general formula (I) and the compound R ¹ SiX ₃ having m = 1 in the general formula (I), and SiX ₄ 1-70 mol%, R ¹ SiX
_The method for producing organic-inorganic composite particles according to claim 1 or 2, wherein the proportion is 399 to 30 mol%. 4. The polymer is a homopolymer of at least one hydrolyzable / polymerizable radically polymerizable group-containing silicon compound selected from the group consisting of compounds represented by the following general formula (III) and derivatives thereof. Alternatively, it is obtained by copolymerizing with a copolymerizable organic monomer.
4. The method for producing organic-inorganic composite particles according to any one of 3 to 3. Embedded image (In the formula, R ³ is a C ₂ -C containing a radically polymerizable group.
₂₀ organic groups, Y is a hydrolyzable group, p = 1 to 3 is an integer, and when p is 2 or more, one of a plurality of R ^{3 is} a C _{2 to} C ₂₀ containing a radically polymerizable group. And other groups are C _{1 to} C ₂₀ organic groups containing no radically polymerizable group. ) 5. The method for producing organic-inorganic composite particles according to any one of claims 1 to 4, wherein the acid exhibits neutral surface activity by being neutralized. 6. The organic-inorganic composite particles obtained have an average particle size of 0.01 to 2 μm.
5. The method for producing organic-inorganic composite particles according to any one of 1. 7. Organic-inorganic composite particles obtained by the manufacturing method according to claim 1. 8. An additive for toner comprising the organic-inorganic composite particles according to claim 7. 9. A toner for developing an electrostatic charge image, which comprises the toner additive according to claim 8.