JPH0612641B2 - Conductive inorganic material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a conductive inorganic material.

[Prior art]

In order to impart conductivity to an inorganic material such as glass or ceramics, a method of subjecting the surface of the inorganic material to a chemical plating treatment and depositing a metal on the surface is known.
In the case of the chemical plating method, in order that metal ions are easily deposited as a metal on the surface of the inorganic material, as a pretreatment on the surface of the inorganic material, it is necessary to perform an etching step, a sensitizing step, an activation step, etc. The whole treatment process is complicated, the stability of the plating bath is poor, and it is necessary to increase the bath ratio during plating, which is not yet satisfactory from an industrial viewpoint.

〔Purpose〕

An object of the present invention is to provide a novel conductive inorganic material which can be produced by a simple method, which is different from the above-mentioned conventional method.

〔Constitution〕

According to the present invention, a surface treatment agent containing a group having an affinity for a copper ion-bonding active group and an inorganic material is attached to the surface of the inorganic material in advance, via the copper ion-bonding active group. Provided is a conductive inorganic material having copper sulfide bonded thereto.

The shape of the inorganic material used as the substrate in the present invention is arbitrary, and it can be used in the form of powder, granule, plate, fiber or the like. Further, as the inorganic material, muscovite, mica, plate-shaped mica minerals such as phlogopite mica, potassium titanate whiskers, gypsum whiskers, wollastonite, asbestos, talc, sepiolite,
Examples thereof include silica, alumina, glass flakes, glass fibers, silicon fibers, carbon fibers, and other various inorganic compounds and ceramics, and the types thereof are not particularly manufactured.

In order to produce the conductive inorganic material of the present invention, first, a surface treatment agent containing a copper ion-bonding active group and a group having an affinity for the inorganic material is used for the surface of the inorganic material as a substrate. A treatment is applied to the surface of the inorganic material in the form of a film. Examples of the copper ion-binding active group include a cyan group, a mercapto group, a quaternary ammonium salt group, a thiocarbonyl group, an amino group, a thiocyanate group, and an isocyanate group. In this case, the quaternary ammonium base is represented by the following formula.

(In the formula, R ¹ , R ² , and R ³ are hydrocarbons such as alkyl, aryl, and aralkyl, and X is an anion such as chlorine ion and sulfate ion.) Also, a group having an affinity for an inorganic material. Examples thereof include a carboxyl group, an ester group, a hydroxyl group, a halogen group, a glycidoxy group, an silane or an alkoxy group bonded to titanium.

The surface treatment agent used in the present invention can also contain two or more groups having the above-mentioned copper ion-bonding active group and / or an affinity for an inorganic material.

The surface treating agent having an active group used in the present invention can be a low molecular weight, an oligomer or a polymer, but a preferable surface treating agent has a copper ion-bonding active group at one terminal and the other. It is a compound having a functional group having an affinity for an inorganic material at the end. Such compounds may be aliphatic or aromatic compounds, and preferred examples thereof include coupling agents such as silane coupling agents.

The surface treatment of the inorganic material using the surface treatment agent, a solution by dissolving the surface treatment agent in a suitable solvent, for example, water, methanol, ethyl alcohol, acetone, toluene, dimethylformamide, dimethyl sulfoxide, dioxane, etc., There is a method in which an inorganic material is brought into contact with the surface treatment agent solution by a method such as dipping, and then the solvent is evaporated and removed. Any method can be used as long as it can bring the inorganic material and the surface treatment agent solution into contact with each other. In the case of the present invention, the copper ion-bonding active group contained in the inorganic material is at least 0.05 wt% or more, preferably 0.1 to 10 wt% in terms of ionic atom (S) or nitrogen atom (N) in the material. It is better to specify the ratio of.

In the present invention, copper sulfide is bonded to the above-mentioned surface-treated inorganic material via its active group.
In this case, the amount of copper sulfide bonded to the inorganic material is
There is no particular restriction, and in general, it is usually 0.05 in terms of metallic copper.
It is about 20% by weight.

There are various methods for binding copper sulfide to the inorganic material, and the first method is as follows.
There is a method in which a monovalent copper ion is first bound to an inorganic material and then the monovalent copper ion is reacted with a sulfiding agent to form copper sulfide. In this case, the monovalent copper ions can be bound by bringing the solution containing the monovalent copper ions or the solution containing the divalent copper ions and the reducing agent into contact with the inorganic material. As the copper compound giving the monovalent copper ion, cuprous chloride,
There are cuprous salts such as cuprous bromide, and copper compounds that give divalent copper ions include cupric chloride, cupric bromide, and cupric sulfate.
There are cupric salts such as copper and cupric acetate. The reducing agent used in combination with the divalent copper ion in order to obtain the monovalent copper ion may be any one capable of converting the divalent copper ion into the monovalent copper ion. There are iron, sodium hypophosphite, hydroxylamine and the like, which are used in an amount sufficient to convert divalent copper ions into monovalent copper ions. As the sulfurizing agent, various sulfur compounds capable of releasing a sulfur atom or a sulfur ion are used, for example, sodium sulfide, dithionous acid, sodium dithionite, sodium thiosulfate, sulfurous acid, sodium hydrogen sulfite, sodium pyrosulfite, Rongalit C, Rongalit Z, hydrogen sulfide, thiourea, thioacetamide and the like. The amount of the sulfiding agent used is not particularly limited and may be any amount sufficient to convert the copper ions bound to the inorganic material into copper sulfide. In addition, in the step of binding the monovalent copper ions (first step), the temperature is from normal temperature to warming, preferably 80
Reaction conditions of about 110 to 120 ° C for about 30 to 120 minutes are adopted. On the other hand, in the step of sulfiding monovalent copper ions, the treated product obtained in the first step is thoroughly washed, and then at room temperature or heating, preferably Is
Reaction conditions of 30 to 120 minutes at 80 to 110 ° C are adopted.
The concentration of copper ions in the solution used in the first step is usually 1 to 30 g / m, preferably 2 to 10 g / m in terms of metal equivalent, and the concentration of the sulfiding agent is 1 to 10 g / m.

As a second method, there is a method in which a solution containing a monovalent copper ion and a sulfiding agent or a solution containing a divalent copper ion, a reducing agent and a sulfiding agent is brought into contact with an inorganic material. In this case, specific examples of the compound generating monovalent copper ions, the compound generating divalent copper ions, and the reducing agent include those described above, and the sulfurizing agent is thiosulfate. The concentration of copper ions in the solution is usually 1 to 30 g /, preferably 2 to 10 g /, and the concentration of the sulfiding agent is 1 to 40 g /
, Preferably 2 to 20 g /. The reaction temperature is from room temperature to warming, preferably 30 to 80 ° C.

Further, as another method, if the sulfurizing agent, preferably hydrogen sulfide, is adsorbed on an inorganic material in advance, and monovalent copper ions are bonded to this to form copper sulfide in the same manner as in the first method. Good.

In the present invention, to stabilize the binding of copper sulfide to the inorganic material, in order to improve the water resistance and moisture resistance of the product,
It is preferable to combine a metal component selected from silver, gold and white metal with copper sulfide. In this case, the white metal includes ruthenium, rhodium, palladium, osmium, iridium and platinum. Such an auxiliary metal component used as an auxiliary component for copper sulfide may be a very small amount as compared with the amount of copper sulfide bonded, and is an inorganic material-equivalent amount of usually 0.0005 to 10% by weight, The amount is preferably 0.005 to 5% by weight, and the ratio with respect to copper sulfide is usually 0.0001 to 0.5, preferably about 0.0001 to 0.3, expressed as an atomic molar ratio M / Cu (M: auxiliary metal).

The addition of the auxiliary metal component to the inorganic material may be carried out by contacting the obtained inorganic material to which copper sulfide is bonded with a solution containing an auxiliary metal ion. In this case, examples of the compound that gives an auxiliary metal ion include inorganic acid salts such as sulfates and nitrates, organic acid salts such as acetates and benzoates, various complex salts such as rhodan complex salts and thiosulfate complex salts. Can be mentioned. The concentration of the auxiliary metal compound in the solution is not particularly limited, but is usually 0.005 to 10 g / preferably 0.01 to 6 g / p in terms of metal. When the copper sulfide-containing inorganic material is immersed in the solution for treatment, the bath ratio to the inorganic material is 5 to 50 parts by weight, preferably 10 to 30 parts by weight, based on 1 part by weight of the inorganic material. Is room temperature to 110 ° C,
The temperature is preferably 30 to 80 ° C, the treatment time is 0.5 to 20 hours,
It is preferably 1 to 10 hours.

As described above, by simply contacting a solution containing an auxiliary metal ion with an inorganic material bound with copper sulfide, the bond stability of sulfide with respect to the inorganic material is increased, and the product has improved water resistance and moisture resistance. In this treatment, a reducing sulfur compound can be used in combination, if necessary, whereby the bond stability of copper sulfide can be further enhanced. The sulfur compound in this case may be any compound having a reducing action, for example, sodium sulfide (N
a ₂ S), hydrogen sulfide (H ₂ S), sulfur dioxide (SO ₂ ), sodium bisulfite (NaHSO ₃ ), sodium thiosulfate (Na ₂ S ₂ O ₃ ),
Sulfurous acid (H ₂ SO ₃ ) Sodium bisulfite (Na ₂ S ₂ O ₅ ), Sodium dithionite (Na ₂ S ₂ O ₄ ), Nitious acid (H ₂ S ₂ O ₄ ), Rongalit (Nithionite salt) And the addition of formalin),
Alternatively, the above mixture may be mentioned. When a gaseous sulfur compound such as hydrogen sulfide or sulfur dioxide is used, it is preferable to perform it under pressure or continuously blow the gaseous sulfur compound into the solution in order to increase the solubility in the solution. The addition amount of the sulfur compound is usually 0.2 to 5 mol, preferably 0.4 to 5 mol, based on 1 mol of the auxiliary metal compound in the solution.
It is in the range of 3 mol. The use of this sulfur compound also has the effect of promoting and stabilizing the binding of the auxiliary metal component onto the copper sulfide-bonded inorganic material, and further improving the conductivity. When the reducing sulfur compound is used in combination, the treatment with a solution containing an auxiliary metal ion can be carried out in the presence of a sulfur compound, and the treatment with the solution can be followed by treatment with a sulfur compound.

In the above aspect, the auxiliary metal component was bonded to the inorganic material to which copper sulfide was previously bonded, but apart from this, the auxiliary metal component is, when bonding copper sulfide to the inorganic material, It is also possible to bond simultaneously, and in this case, the auxiliary metal component may coexist with copper ions.

In the present invention, if necessary, a conductive metal can be further attached to the above-mentioned inorganic material to which copper sulfide is bonded via the copper sulfide. In this case, the conductive metal can be attached by the usual electrolytic plating method. That is, an inorganic material to which copper sulfide is bonded may be used as a cathode, and current may be passed between the cathode and the anode in an electrolytic bath containing required metal ions. As a metal for electroplating,
Any conductive material may be used, and for example, nickel, copper cobalt, lead, zinc, tin or the like is used. The adhesion of this conductive metal is 10 to 80% by weight, preferably
15 to 50% by weight. This electrolytic plating treatment can further improve the conductivity of the copper sulfide-bonded inorganic material.

〔effect〕

The present invention has the above-mentioned constitution, and according to the present invention, since it is possible to impart high conductivity to the inorganic material only by binding a small amount of copper sulfide, the practical value thereof is large. Moreover, in the case of the conductive inorganic material of the present invention,
Compared with the conventional method, there is an advantage that the manufacturing is easy.

The product of the present invention is mixed in plastics and is advantageously applied as an electromagnetic wave shielding material or the like.

〔Example〕

 Next, the present invention will be described in more detail with reference to Examples.

Example 1 Glass fiber (33.7 tex, filament type) 10
g, γ-cyanopropyltriethoxysilane 0.5 g water 1
It was dissolved in 00 ° C., immersed in a solution whose pH was adjusted to 3.5 with acetic acid, treated at room temperature for 30 minutes, and washed with water.

Next, the treated glass fiber, copper sulfate 15g,
Sodium thiosulfate 10 g, acidic sodium sulfite 5 g, acetic acid 3 g, and sodium acetate 3 g in a solution of 200 cc of water at 60 ° C.
Time processing was performed. The treated glass fiber had an olive gray color and an electric resistivity of 3.2 × 10 ^-2 Ω · cm.

Example 2 10 g of mica pieces was immersed in a solution of 0.5 g of γ-mercaptopropyltrimethoxysilane dissolved in 100 cc of water and adjusted to pH 3.5 with acetic acid, treated at room temperature for 40 minutes, and washed with water. Copper sulfide bonding treatment was performed under the same conditions as in 1. The treated mica exhibited a black gray color and its surface electrical resistivity was 350Ω.

Example 3 20 g of a piece of a white porcelain beaker was dissolved in 0.5 g of γ-aminopyropyrtriethoxysilane in 100 cc of water, and pH was adjusted to 3.5 with acetic acid.
The sample was dipped in the solution prepared as above, treated at 50 ° C. for 15 minutes, washed with water, and then bound with copper sulfide under the same conditions as in Example 1. The obtained product had an olive gray color and its surface electrical resistivity was 220Ω.

Example 4 10 g of glass fiber was dissolved in 100 cc of isocyanatopropyltriethoxysilane in 100 cc of methanol, immersed in a solution adjusted to pH 3.5 with acetic acid, treated at 40 ° C. for 20 minutes, and then washed with water. did. When the obtained glass fiber was subjected to copper sulfide bonding treatment in the same manner as in Example 1, a product having an electric specific resistance of 2.6 × 10 ⁻¹ Ω · cm was obtained.

Example 5 An experiment was conducted in the same manner as in Example 1 except that olivine was used instead of the glass fiber, and a product having a surface hue of 380Ω having a gray hue was obtained.

Example 6 5 g of mica and 0.5 g of trimethoxysilylyloctadecyldimethylammonium chloride in methanol
It was immersed in a solution dissolved in 100 cc, treated at room temperature for 30 minutes, and then dried at 80 ° C for 20 minutes. The dried product was subjected to copper sulfide bonding treatment in the same manner as in Example 1 to obtain a product showing a black gray color and a surface electric resistivity of 410Ω.

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Claims (1)

[Claims] 1. A sulfur treatment is performed on an inorganic material having a surface-treating agent containing a copper ion-bonding active group and a group having an affinity for the inorganic material attached to the surface in advance through the copper ion-bonding active group. A conductive inorganic material, which is characterized by binding copper.