JPS61155482A - Bondable composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent storage stability and electrical conductivity, by blending an acid-treated electrically conductive powder and fumed silica with a 2-cyanoacrylate. CONSTITUTION:An electrically conductive powder such as silver, copper, Ni or Al powder is immersed in water contg. not more than 20wt% org. acid (anhydride) (e.g. acetic acid or its anhydride) or org. acid ester contg. free acid group (e.g. ethylene glycol ditrimellitate) or in a 9C or lower aliph. alcohol soln., treated for 1minto one hr and dried to obtain an acid-treated electrically conductive powder (A). 10-200pts.wt. component A, 0.1-20pts.wt. hydrophobic fumed silica having a diameter of 1-100mmu and optionally additives such as stabilizer, thickener, plasticizer, crosslinking agent, etc. are added to 100pts.wt. 2-cyanoacrylate.

Description

Detailed Description of the Invention (a) Purpose of the Invention "Field of Industrial Application" The composition of the present invention is useful in the electrical and electronic materials industry for the production of a fixed circuit to the contact point of a lead wire or for coating for electromagnetic shielding. It is used for such purposes and is widely used in the electronic equipment industry, the electrical machinery industry, and the general machine manufacturing industry.

"Prior Art" Hitherto, paints, conductive paints, etc. have been widely used and have played an important role for the above-mentioned purposes.

Further, in order to take advantage of the rapid hardening properties of 2-cyanoacrylate adhesives, attempts have been made to add conductive powder to 2-cyanoacrylate adhesives.

``Problems to be Solved by the Invention'' Solder used for fixing lead wires, etc. needs to be heated during use, which not only degrades the performance of electronic components but also requires a large amount of energy. have.

Further, conventional conductive paints also have the problem that they require a large amount of heat or light and take up to 5 hours to cure.

Furthermore, attempts have been made to add conductive powder to 2-cyanoacrylate adhesive to create a conductive instant adhesive, but the conductive powder is not stably dispersed in 2-cyanoacrylate, and furthermore, during application, °Dragging′°Stringing occurs′
The inventors of the present invention have developed a structure 1 of the conductive invention which solves the above-mentioned problems. ``Means for solving the problems'' The inventors
The inventors have discovered that the above problems can be solved by using a conductive powder and made silica that have been brought into contact with an acid, and have completed the present invention.

That is, the present invention provides conductive powder fused with acid and 7S.
The present invention relates to a 2-cyabacrylate-based soy sauce composition characterized by containing mudosilica.

Conductive powder Various types of conductive powder can be used in the present invention, but specific examples include silver, steel, nickel, aluminum, carbon, gold, palladium, platinum, ruthenium, and Composite powder etc. containing them.

The conductive powder used in the present invention is used after being brought into contact with an acid, and examples of the acid to be brought into contact include inorganic acids such as hydrochloric acid, phosphoric acid, and organic acids such as those exemplified below. Examples include organic acid anhydrides and organic acid esters having acid groups.

Organic acids include acetic acid, propionic acid, butyric acid, trifluoroacetic acid, valeric acid, hexanoic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, cinnamic acid, benzoic acid, methanesulfonic acid, Toluenesulfonic acid, ) IJ fluoromethanesulfonic acid, toluene disulfonic acid, itacone, aconitic acid, phthalic acid, trimellitic acid, etc., and organic acid anhydrides include acetic anhydride, propionic anhydride, butyric anhydride, and anhydride. Valeric acid anhydride, succinic anhydride, glutaric anhydride, adipic anhydride, maleic anhydride, itanic anhydride, aconitic anhydride, phthalic anhydride.

These include trimellitic anhydride.

Examples of the organic acid ester having an acid group include compounds such as ethylene glycol ditrimellitate, trimethylene glycol ditrimellitate, and Recaresin TMTA (part name manufactured by Shin Nippon Chemical Co., Ltd.).

Preferred acids for the present invention include organic acids such as toluenesulfonic acid and organic acid anhydrides such as trimellitic anhydride, and when they are brought into contact with the conductive powder, it is preferable to use them as a methanol solution. .

The conductive powder used in the present invention is brought into contact with the above-mentioned inorganic acid, organic acid, organic acid anhydride, or organic acid ester having an acid group, and the contacting method is by immersing it in a nucleic acid solution. However, some of these acids are strong acids or are solid at room temperature, so in the immersion or coating process as a contact method, it is difficult to use them as a solution. This is also a preferred method for the present invention from the viewpoint of not impairing the properties of the powder.

The solvent for preparing the solution is not particularly limited as long as it dissolves the acid, but primary solvents are preferably used.

Water, aliphatic alcohols having up to 9 carbon atoms such as methanol, ethanol, cyclohexanol, etc., ketones having up to 9 carbon atoms such as acetone, methyl ether ketone, etc., esters from acids having up to 3 carbon atoms and alcohols having up to 7 carbon atoms, e.g. Ethyl acetate, butyl acetate, etc., aliphatic ethers such as diethyl ether, tetrahydrofuran, dioxane, etc., halogenated hydrocarbons such as chloroform, trichloroethane, trichlorotrifluoroethane, etc.

There is no difference in the effect of the present invention whether these solvents are used alone or as a mixed solvent.

The concentration of acid in the solution using the above solvent is preferably 20% by weight or less, more preferably 15 to 5% by weight.

The method of bringing the powder into contact with the above acid, that is, immersing it in the solution of the above acid or applying the solution, is the conventional method of immersing the powder in the same solution for about 1 minute to 1 hour at room temperature or applying it with a spray gun, etc. measures are adopted.

Powder immersed or applied in a solution can be separated by over-separation, static separation, centrifugation, etc. to remove excess solution, and then the solvent can be removed by drying at room temperature or under heating under normal pressure or reduced pressure. preferable.

The content of the conductive powder in the composition of the present invention is preferably 10 to 200 parts by weight, more preferably 50 to 100 parts by weight, relative to 100 parts by weight of 2-cyanoacrylate. There is a risk that adhesive WaS
It becomes difficult to fully impart sex to taste and performance.

0 fumed silica The fumed silica used in the composition of the present invention has a diameter of 1
-1007 FLμ, preferably 5 to 50 μm, is fine particle silica, such as highly dispersible amorphous silica obtained by hydrolyzing silicon tetrachloride in an oxyhydrogen flame. Also used in the present invention are alumina-containing silica, titanium oxide-containing silica, and iron oxide-containing silica by coexisting chlorides such as titanium chloride, aluminum chloride, and iron chloride when hydrolyzed in a hydrogen flame.

Fumed silica is used as a thickener in the composition of the present invention to stably disperse the conductive powder, effectively exhibit a conductive effect, and improve workability. Hydrophobic silica, which is obtained by making the surface of 7-umed silica hydrophobic, is a particularly preferred silica in the present invention from the viewpoint of thickening properties such as chicken tropic properties and storage stability.

Hydrophobic silica is an alkyl group having a hydrophobic group such as n-octyltrialkoxysilane, which is the surface of ordinary hydrophilic silica.
Aryl and aralkyl silane coupling agents, silylating agents such as dimethyldichlorosilane and hexamethyldisilazane, polydimethylsiloxanes with aqueous dispersion groups at the end, higher alcohols such as stearyl alcohol, and higher alcohols such as stearic acid. It is obtained by treating paper with fatty acids, and specifically, the following commercially available products can be used.

Degussa treated with dimethyldichlorosilane, n-octyltrimethoxysilane, silicone oil, etc.
guasa) AERO5I L R792, R80
5, R202, 'P Yaboy) (CABOT) Company f) Cab-0-8ilN7 treated with organosilicon compound
0-TS etc. are used as commercial products.

Among these hydrophobic silicas, hydrophobic silicas having a carbon content of more than 1 are particularly preferred for the present invention.

It is used to stably disperse and produce a conductive effect to improve workability, and its blending ratio is 2.
- It may be determined by considering the type of cyanoacrylate, the amount and type of other optional additives, the material to be applied, the coating method, etc., but usually, based on 100 parts by weight of 2-cyanoacrylate, Fuyumed silica is α1-2
It is preferable that 0 parts by weight is added, more preferably 1 to 0 parts by weight.
It is 10 parts by weight.

In addition, it is important for the thickened composition to have thixotropic properties in order to solve the problems of the present invention.
From this point of view as well, it is preferable to consider the amount of fumed silica to be added.

Thixotropic properties are generally expressed by Brookfield (Br
It is determined by the thixotropy index below using the viscosity.

η1 Chickentropy index knee η! However, here, η1 is the viscosity at the rotational speed n, and η is the viscosity at the rotational speed n/10.The composition of the present invention preferably has a chickentropy index of 2.0 or more, and more preferably 5.0 or more. Therefore, it is preferable to determine the type and amount of fumed silica to be blended so as to exhibit such chicken-tropic properties.

O cyanoacrylates include all the usual esters. in particular,
Methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, especially butyl, t-butyl, amyl,
n-hexyl, cyclohexyl, heptyl, n-octyl, 2-ethylhexyl, dodecyl, allyl, propargyl, benzyl, phenyl, methylcellosolve, ethylcellosolve, 2-chloroethyl, hexafluoropropyl, trifluoroethyl, 2-cyanide 2- such as ethyl
Examples include cyanoacrylate.

Usually, 2-cyanoacrylate adhesives contain stabilizers,
In the present invention, thickeners, plasticizers, crosslinking agents, etc. may also be added. Stabilizers include SO2, sulfonic acids, sultones, lactones,
Boron fluoride, hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, etc. 1-100
Several polymers such as methyl methacrylate polymer, 2-cyanoacrylate poly(i-), and acrylic rubber are added as a viscous agent. Additionally, to improve the flexibility of the polymer, dioctyl phthalate, sebacic acid ester,
Plasticizers such as phosphate esters may also be added. In order to give the adhesively cured polymer a three-dimensional structure, a small amount of a polyfunctional vinyl monomer such as alkylene diacrylate, alkylene dimethacrylate, trimethylolprobant acrylate, triallylisocyanurate, etc. may be added.

In such cases, an improvement in heat resistance is seen.

When the powder comes into contact with an acid, the surface absorbs the acid and does not impair its storage stability, and because of the thickening with 7-umed silica, it is dispersed with good stability and fully exhibits its conductive effect. , plays the role of solder and conductive paint without impairing workability.

``Example'' Hereinafter, examples and comparative examples will be given to demonstrate the present invention, and the silver powder to which the sulfuric acid aqueous solution was attached was collected by filtration, and the solvent was removed under vacuum for about 10 hours, and the silver powder was exposed to acid. A silver powder was obtained. 100 parts by weight of this powder, AERO3IL R20
2 (manufactured by Nippon Aerosil Co., Ltd.) and 5 parts by weight of ethyl 2-cyanoacrylate 100 were tested.

The tensile shear strength was measured according to JIS K6850 using steel as a test piece. Also, the setting time for copper is within 30 seconds. The presence or absence of dripping in this composition was determined according to Human STM D2730.

Storage stability and dispersibility are determined after filling in a polyethylene container.
The above condition was observed after being left in the refrigerator (0 to 10°C) for 10 days. The results are shown in Table 1.

Example z-5 When 100 parts by weight of silver powder and 5 parts by weight of the same filmed silica as in Example t were added, the composition generated heat and solidified immediately after the addition.

Comparative Example λ, 5 Examples 1. 100 parts by weight of acid-contacted silver powder was added to 100 parts by weight of ethyl 2-cyanoacrylate, and the same procedure as in Example 1 was carried out, and the test was conducted in accordance with the above example. The results are shown in Table 1.

(c) Effects of the Invention By using the composition of the present invention, work such as fixing lead wires to contacts, fabricating circuits, and painting for electromagnetic shielding can be performed at room temperature and instantaneously with the required effects, and furthermore, work can be done instantly at room temperature. It is easy to use with no dripping or stringiness, and will not damage electrical/electronic parts, plastics, cases, etc. due to heat.

The present invention can be used very effectively in the field of manufacturing electrical and electronic parts as an alternative to solder and conductive paint, and the effects produced by the composition of the present invention are immeasurable.

Claims (1)

[Claims] 1. A 2-cyanoacrylate adhesive composition containing a conductive powder and fumed silica that has been brought into contact with an acid.