JPH10158543A - Inorganic/organic hybrid pigment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject pigment as a new functional microscopic composite material having light fastness, heat resistance and dispersibility all together in a high level by chemically modifying the surface of inorganic fine particles with an organic material. SOLUTION: This inorganic/organic pigment is obtained by chemically modifying the surface of inorganic fine particles with an organic material. The inorganic fine particles having >=100nm particle diameter is preferable. Also, the inorganic fine particles are preferably a crystalline-based material. More concretely, e.g. in the case of using MgAl2 O4 (spinel) as the inorganic fine particles, magnesium-bis-tetraisopropoxy aluminate Mg[Al(OiPR)4 ]2 } synthesized by using metallic Mg and Al(OiPr)3 as the starting material, iPrOH as a solvent and HgCl2 as a catalyst, then coordinating acetoaceoxyethylmethacrylate as an organic material thereto, then hydrolyzing the obtained hybrid precursor and maturing them to obtain the objective pigment having MGAl2 O4 fine particles dispersed in an organic matrix.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a composite material composed of an inorganic material and an organic material at a microscopic level, which can be widely used for pigments used in inks, paints and the like, or fine particles used as raw materials for ceramics. A new type of high-performance, multi-functional pigment.

[0002]

2. Description of the Related Art At present, there are two types of pigments used in the field of inks and paints: inorganic pigments and organic pigments. Inorganic pigments have advantages such as excellent light resistance and heat resistance, no discoloration, great hiding power, and insolubility in organic solvents. Not reachable. Organic pigments, on the other hand, have the advantage of being rich in color types and vivid, having high coloring power and fine particles, but have the drawback that they are inferior in light resistance and heat resistance because they are organic substances and are liable to discolor. ing. Therefore, hitherto, it has not been possible to achieve both light resistance, heat resistance and dispersibility at a high level by using an inorganic pigment or an organic pigment alone.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a novel functional microscopic composite material in which the surface of inorganic fine particles is modified with an organic substance, that is, an inorganic / organic hybrid pigment produced by a chemical method. The purpose is to:

[0004]

The above object can be attained by combining inorganic fine particles as a pigment and an organic material as a dispersant in situ at a micrometer / nanometer level in situ.

In the inorganic / organic hybrid pigment of the present invention, the surface of the inorganic fine particles is chemically modified with an organic substance, and the particle diameter of the inorganic fine particles is 100 nm or less. The dispersibility and dispersion stability of pigments in paints and paints have been dramatically improved.

[0006] The inorganic / organic hybrid pigment of the present invention comprises
By selecting the type and molecular weight of the organic substance on the surface of the inorganic fine particles, it can be used without any distinction in either an aqueous or non-aqueous dispersion system, and furthermore, a dispersant which is essential in a conventional pigment dispersion system May be omitted. When a dispersant is used, the inorganic /
Organic hybrid pigments have an extremely high affinity for dispersants because the surface of the inorganic fine particles is already chemically modified with organic substances, so it is easy to obtain a dispersion having excellent dispersibility and dispersion stability. it can.

Further, in the inorganic / organic hybrid pigment of the present invention, since the inorganic fine particles are crystalline, there is no problem in light resistance and heat resistance.

In the inorganic / organic hybrid pigment of the present invention, an organic substance on the surface of inorganic fine particles and an organic substance on the surface of other inorganic fine particles are combined to form a two-dimensional and / or three-dimensional network structure. It is also possible to use materials of various viscosities or hardnesses up to solid materials. In this case, the viscosity and hardness of the material can be arbitrarily controlled by controlling the type and molecular weight of the organic substance on the surface of the inorganic fine particles and the number of bonds between the organic substances.

The inorganic / organic hybrid pigment of the present invention comprises
First, inorganic fine particles are synthesized by a chemical reaction. At this time, an organic substance having a polymerizable unsaturated group is coordinated with the inorganic fine particles to synthesize a composite precursor. Thereafter, the composite precursor is hydrolyzed to obtain an inorganic / organic hybrid pigment in which the surface of the crystalline inorganic fine particles is chemically modified with an organic substance. The dispersibility and dispersion stability of the inorganic fine particles can also be remarkably improved by increasing the chain length of the organic substance or polymerizing different organic substances during the synthesis reaction.

Specifically, MgAl ₂ is used as the inorganic fine particles.
When O ₄ (spinel) is used, M
g (metal) and Al (O ⁱ Pr) ₃ , ⁱ P as a solvent
ROH, by using HgCl ₂ as catalyst, acetoacetoxy with magnesium-bis-tetra-isopropoxy aluminate ^{(Mg [Al (O i Pr} ) 4] 2, MPA) were synthesized, to which radical-polymerizable unsaturated group A hybrid precursor is synthesized by coordinating ethyl methacrylate (AaemH). By conducting hydrolysis and aging of the hybrid precursor, an inorganic / organic hybrid pigment in which MgAl ₂ O ₄ fine particles are dispersed in an organic matrix can be obtained.

The color tone of the inorganic / organic hybrid pigment of the present invention can be controlled by adding various elements to inorganic fine particles by substitution.

As an ink material, MgAl _{2 is} used as inorganic fine particles.
When O ₄ is used, the cyan pigment is Co, Al, Si
The magenta pigment can be obtained by adding Zn, Al, Cr and the like, and the yellow pigment can be obtained by adding Zn, Cr, Fe and the like.

In the case of MgAl ₂ O ₄ , for example, cyan pigment is replaced by replacing Mg mainly by 100% with Co, magenta pigment is replaced by replacing Al mainly with 10% by Cr, and Mg is replaced by Mg. Mainly Zn, Al mainly (C
(r, Fe) can be substituted up to 30% to obtain a yellow pigment. Each substitution element may be added in the form of a metal alkoxide during the synthesis of the composite precursor.

The inorganic fine particles in the present invention include oxides such as titanium oxide, zinc oxide, silicon oxide, iron oxide, tin oxide, zirconium oxide and aluminum oxide, or spinel, mullite, zircon, cordierite, steatite, Complex oxides such as forsterite, or barium titanate, lead titanate, PZT, PLZT
For example, any material synthesized by a chemical reaction can be used.

In the present invention, the organic substance that modifies the surface of the inorganic fine particles may be any organic substance having at least one radically polymerizable unsaturated group, and examples thereof include the following.

1) (meth) acrylate containing an acetoacetoxy group, such as acetoacetoxyethyl methacrylate, acetoacetoxyethyl acrylate, etc .; 2) alkyl (meth) acrylate, such as methyl (meth) acrylate, ethyl (meth) acrylate;
3) polymerizable aromatic compounds, for example, styrene, α-methylstyrene, t-butylstyrene, 4-vinylpyridine, and the like; 4) carboxyl group-containing monomeric monomer, for example, n-butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; Body, for example, acrylic acid,
Methacrylic acid, crotonic acid, itaconic acid, maleic acid,
5) hydroxyl group-containing monomer such as 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, allyl alcohol, methallyl alcohol; 6) nitrogen-containing 7) a polymerizable amide, such as acrylamide, methacrylamide, etc .; 8) a polymerizable nitrile, such as acrylonitrile, methacrylonitrile; ) Polymerizable glycidyl compounds, such as glycidyl (meth) acrylate; 10) α-olefins, such as ethylene and propylene; 11) Vinyl compounds, such as vinyl acetate and vinyl propionate; 12) Diene compounds, examples For example, butadiene, isoprene and the like.

These monomers can be used alone or in combination.

Examples of monomers having two or more radically polymerizable unsaturated groups in the molecule include ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and tetraethylene glycol di (meth) acrylate. A) acrylate, 1,3-butylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexane Diol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerol di (meth) acrylate, glycerol allyloxydi (meth) acrylate, 1,1,
1-trishydroxymethylethanedi (meth) acrylate, 1,1,1-trishydroxymethylethanetri (meth) acrylate, 1,1,1-trishydroxymethylpropanedi (meth) acrylate, 1,1,1-
Trishydroxymethylpropane tri (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate, allyl (meth) acrylate, divinylbenzene and the like can be mentioned.

The inorganic / organic hybrid pigment of the present invention comprises
In addition to pigments used for inks and paints, or raw material fine particles used for ceramics and the like, they can be used in fields such as magnetic sensors, micromachines, microactuators, magnetic shields, and drag carriers.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

[0022]

EXAMPLE An example in which MgAl ₂ O ₄ is used as the inorganic fine particles will be described.

Mg (metal): 0.3646 g and A
l (O ⁱ Pr) ₃ : 6.1269 g was added to HgCl ₂ : 0.2
^I containing 5 g PrOH: in 150ml sink 40 hours ring, after which the solvent was evaporated, a transparent and viscous Mg
[Al (O ⁱ Pr) ₄ ] ₂ (MAI) is obtained.

Next, acetoacetoxyethyl methacrylate (AaemH) was added to a 0.1 M ⁱ PrOH solution of MAI.
Was added with stirring so that MAI: AaemH = 1: 1, followed by stirring at 50 ° C. and then evaporating the solvent to obtain a hybrid precursor in the form of a transparent solid (MAlaaeH).
m).

Then, 0.1M ⁱ Pr of MAlaaem
Water was added to the OH solution while stirring so that Malaam: water = 1: 6, and then refluxed at about 90 ° C. for 24 hours, followed by aging and hydrolysis. Finally, the solvent was evaporated to give a white powdery inorganic substance. / Organic hybrid pigment is obtained.

From X-ray diffraction and electron microscope observation, it was found that the inorganic / organic hybrid pigment obtained above had a particle size of about 1%.
It was confirmed that 0 nm crystalline MgAl ₂ O ₄ was uniformly dispersed in the matrix.

Claims (4)

[Claims] 1. An inorganic / organic hybrid pigment in which the surface of inorganic fine particles is chemically modified with an organic substance. 2. The inorganic / organic hybrid pigment according to claim 1, wherein the particle diameter of the inorganic fine particles is 100 nm or less. 3. The inorganic / organic hybrid pigment according to claim 1, wherein said inorganic fine particles are crystalline. 4. The inorganic / organic hybrid pigment according to claim 1, wherein the organic substance on the surface of the inorganic fine particles is combined with an organic substance on the surface of other inorganic fine particles to form a network structure.