JPH11323182A - Atypical tabular metal powder dispersion and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an atypical tabular metal powder dispersion which is a dispersion of a finely particulate metal powder of submicron order having a metallic brightness in an easily handleable org. solvent and does not contain a resin, etc., and to which a resin, etc., suitable for the purpose of use can be added later. SOLUTION: This dispersion is prepd. by forming at least one thin vapor deposition layer from a component other than the main metal component on a base film, forming at least one thin metal deposition layer on the above- formed layer, peeling at between the layers by mechanical peeling, jetting or penetration of a volatile org. solvent, etc., putting a thin film having at least one of the peeled thin metal deposition layers into a volatile org. solvent, and finely dividing the thin film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a volatile organic solvent dispersion containing at least an atypical flat piece of a metal-deposited thin layer, and to a method for producing the dispersion.

[0002]

2. Description of the Related Art Finely divided metal powders have been widely used as decorations, information recording media, catalysts and the like, and various production methods have been proposed. Things are known. For example, fine powder or foil pieces from a laminate in which a resin (protection) layer is formed on at least one surface of a metal vapor-deposited film, fine powder by a metal vapor deposition method, mechanical fine powder by pulverization of a metal foil, and the like. .

[0003]

A fine powder or a foil piece from a laminate in which a resin (protection) layer is formed on at least one surface of a conventional metal vapor-deposited film is excellent in decorativeness and has a metallic luster in printing and drawing. Although it is used for giving, and it is also excellent in environmental stability due to the presence of the resin protective layer, the presence of the resin layer becomes unnecessary or obstructive depending on the application, and the thickness of the resin layer However, there has been a problem when the size of the pulverized powder is limited and an inorganic flat piece having a more suitable size is required. Fine powder obtained by metal deposition is extremely excellent in its fineness, but even if it can be used for special applications such as catalysts, handling of the obtained fine powder is often very difficult and complicated. In addition, there is a problem in that even when the material is fine, it does not have metallic luster when used in a decorative body. Mechanically pulverized powder obtained by pulverizing metal foils is excellent in economical efficiency and widely used, but there is a lower limit in the thickness and size of the pulverized powder, and it is difficult to obtain a micron-order powder. There was a problem that it could not be used for applications using finer powders of submicron order or less. The present invention is intended to solve the problem of such conventional fine powder, has no resin layer, possesses metallic luster, and is a fine powder of submicron order or less, Eliminating the difficulty of handling of fine powders,
In particular, eliminating the difficulty of handling fine powder in the dry state,
It is an object of the present invention to provide a volatile organic solvent dispersion of atypical flat piece metal powder.

[0004]

That is, the present invention provides an atypical flat metal powder in which a thin film having a metal-deposited thin layer mainly composed of at least one metal as a main component is thinned,
The thickness of the atypical flat metal powder is 0.03 to 0.5 μm,
The ratio of the area of the deflected plane to the thickness of the thin film is 5 [μm] to 5 × 1
0 ⁶ a [[mu] m], the thin film is mainly configured with atypical flat metal powder having a deposition thin layer portions other than the component, the volatile organic solvent and atypical, characterized in that it consists of flat metal powder dispersed Body, and on the base film, forming one or more vapor-deposited thin layers of components other than the main constituent metal, and forming one or more vapor-deposited thin layers of a metal containing the main constituent metal on the layer, By mechanical peeling, injection of a volatile organic solvent, penetration, etc., the layers are peeled off, and a thin film having one or more metal thin layers including at least one of the main constituent metal metal thin layers is incorporated into the volatile organic solvent. This is a method for manufacturing an atypical flat metal powder dispersion in which the thin film is dispersed as a thinned atypical flat metal powder.

According to the present invention, it is possible to obtain a fine and easy-to-handle volatile dispersion having a metallic luster and of a submicron order, and this dispersion can be obtained by dispersing a resin-free dispersion from a resin layer. It is an atypical flat metal powder dispersion that can be added and contained later depending on the purpose of use, depending on the purpose of use, and is easy to exchange solvents. In addition, since the dispersion is a dispersion in a volatile organic solvent, it is extremely easy to change the concentration of the atypical flat metal powder in the dispersion, and a dry atypical flat metal powder to a dilute dispersion can be easily obtained. This can be used widely from inks to conductive pastes or dry metal glitters.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The base film in the present invention includes polyester films such as polytetrafluoroethylene, polyethylene, polypropylene, polyethylene terephthalate and polyethylene naphthalate;
Examples thereof include polyamide films such as nylon and 6 nylon, polycarbonate films, triacetate films, and polyimide films, but are not particularly limited. The thickness of these films is from 4 μm to 40 μm. If the thickness is less than 4 μm, there are many problems in handling properties in the process and the like. If the thickness exceeds 40 μm, flexibility is poor and problems such as peeling are increased.

The metal constituting the metal-deposited thin layer which is a main component of the atypical flat metal powder in the present invention includes aluminum, gold, silver, copper, platinum, palladium, nickel, ruthenium, chromium, zinc, tin, and the like. Indium, titanium, or an alloy containing these metals as a main component is used. As the components constituting the vapor-deposited thin film layer other than the main components in the present invention, the above-mentioned metals can be used, and in addition, aluminum oxide, silicon and its oxides can also be used. The method for forming the vapor-deposited thin layer on the base film is not particularly limited in the method, but a dry thin-film forming method such as vapor deposition, sputtering and ion plating, which is called vapor deposition, is preferably employed. In the present invention, two or more layers of the above-mentioned metals and the like are formed on a base film by vapor deposition, and the formed layers are peeled off by mechanical brushing or film stretching, or a volatile organic solvent is injected or permeated. By peeling, taking the peeled thin film in a volatile organic solvent, thinning the thin film in the plane direction,
An atypical flat metal powder dispersion in a volatile organic solvent is obtained. In the present invention, the thin metal layer and the thin film have an oxidized state on their very surfaces as is well known, but such a state is intentionally expressed as a metal.

Since the atypical flat metal powder of the present invention is produced by the above-described method, for example, a metal-deposited thin layer containing aluminum as a main component and a metal-deposited thin layer containing gold as a sub-component are laminated on the entire surface. Metallized thin layer containing aluminum as a main component and metallized thin layer containing silver as a subcomponent laminated on the entire surface or partially laminated and attached, A metal-deposited thin layer having aluminum as the main component, a metal-deposited thin layer having aluminum as the main component, and a metal-deposited thin layer having aluminum as the main component The metal-deposited thin layer as a sub-component may be laminated on the entire surface or partially adhered.

The atypical flat metal powder of the present invention comprises a thin film having a main component and a thin layer other than the main component, and the thickness is 0.03 to 0.5 μm. When the thickness is less than 0.03 μm, peeling becomes difficult, and in many cases, the metal glittering property is insufficient. On the other hand, when the thickness exceeds 0.5 μm, there is no increase in metal glitter and it is economically disadvantageous.
Further, this departs from the gist of the present invention, which aims at a size on the order of submicrons.

In the present invention, the volatile organic solvent is not particularly limited as long as it has a boiling point in the range of about 50 ° C. to 170 ° C., but low-boiling ketones such as acetone and methyl ethyl ketone, n-hexane, cyclohexane , Etc., such as hydrocarbons, ethyl alcohol, isopropyl alcohol, n-butanol, etc., and esters such as methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, etc., which do not dissolve the base film, have low toxicity, It can be appropriately selected and used from the viewpoint of permeability. In the volatile organic solvent of the present invention, a coloring agent such as a minute amount of a dye, a viscosity modifier such as glycerin and diethylene glycol, a surfactant and the like are added and contained, unless departing from the gist of the present invention. Is also good.

[0011] The deposition thin layer formed on the base film may be peeled by stretching the base film, peeling by mechanical friction or vibration, peeling by immersion in the solvent, peeling by spraying the solvent, or the like. The peeling is performed by these methods alone or in combination. In any case, the peeled thin film is subjected to separate thinning simultaneously with the peeling, but is taken into the volatile organic solvent,
Obtained as a dispersion in a volatile organic solvent. The peeling in the present invention is one that utilizes delamination properties such as peelability between differently deposited thin layers having poor adhesion, or peelability between differently deposited thin layers that are particularly excellent in solvent permeability. It is. The pulverization (pulverization) method is not particularly limited, but is not particularly limited as long as it is used for wet pulverization such as a jet mill, a ball mill, a ring roll mill, and a tube mill. This thinning (pulverization) may be performed in advance by dry-type thinning, but it is preferable that the final thinning be performed in a volatile organic solvent. In this case, a coloring material such as a dye, alcohol, etc. (Pulverization) by simultaneously using a viscosity modifier, a settling stabilizer, a surfactant and the like. Further, even if the thinning (pulverization) is not particularly actively performed, the thin film may become a fine irregular flat piece only by peeling from the peelable film.

The thickness of the atypical flat metal powder of the obtained atypical flat metal powder dispersion is 0.03 μm.
To 0.5 μm, preferably 0.05 μm to 0.3 μm. The size of the deviated plane is not a fixed shape such as a circle or a square, but is represented by its area, and a value obtained by dividing the area by the thickness is 5 to 5 × 10 ⁶ [μm], and is preferably It is 10 to 10 ⁶ [μm]. When this value is less than 5, almost no performance is exhibited in metallic glitter, and in particular, the hiding power when used in inks, paints and the like becomes insufficient. The upper limit is not particularly limited. For example, when the atypical flat metal powder of the present invention is mixed into lacquer (including synthetic) by solvent exchange or the like, when the thickness is 0.2 μm, Average area of atypical flat piece is 1m
m × 1 mm, and the value is 1 × 10 ⁶ /0.2, which is 5,000,000.
It is about 00,000. In the present invention, the ratio between the atypical flat metal powder and the volatile organic solvent is not particularly limited, but is preferably from 1:30 to 1: 4. Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

[0013]

Example ** Example 1 Aluminum was evaporated to a thickness of 0.04 μm on a polyethylene terephthalate film having a thickness of 12 μm to form an aluminum evaporated thin layer, and gold was deposited on the aluminum evaporated thin layer to a thickness of 0.02 μm. To form a gold-deposited thin layer. Further, aluminum was added on the gold-deposited thin layer in a thickness of 0.1 mm.
Vaporized to a thickness of 08 µm, a thin layer of aluminum is formed, and the resulting laminate is run in the longitudinal direction while stretching the base film, polyethylene terephthalate film, by 10% in the longitudinal direction, and simultaneously circulates and injects ethanol. Meanwhile, an atypical flat metal flake of a thin film body in which a gold-deposited thin layer of a main component of an aluminum-deposited thin layer dispersed in ethanol was almost entirely laminated was obtained. In ethanol, further homogenize (pulverize) with a homomixer to obtain a thickness of 0.10 μm and an average flat area of 0.10 μm.
Was 320 [μm].

** Example 2 Silicon oxide was deposited to a thickness of 0.05 μm on a polyethylene terephthalate film having a thickness of 20 μm to form a silicon oxide thin layer, and gold was coated on the silicon oxide thin layer with a thickness of 0.08 μm. Evaporated to a thickness to form a thin gold deposited layer. The obtained laminate is run in the longitudinal direction while stretching the base film, polyethylene terephthalate film, in the longitudinal direction by 10%, and at the same time, ethanol is circulated and jetted, so that the thin film composed mainly of gold is not dissolved in ethanol. Obtained flat metal flakes. A thin layer of silicon oxide is partially adhered to the thin film composed mainly of gold, but most of the thin layer is a thin layer of gold, and is thinned (crushed) in ethanol with a homomixer.
And a thickness of 0.08 μm, and the average area of the deviated plane
The value divided by 8 μm was 1200 [μm].

** Example 3 Aluminum was evaporated to a thickness of 0.03 μm on a polyethylene terephthalate film having a thickness of 12 μm to form an aluminum evaporated thin layer, and silver was evaporated to a thickness of 0.02 μm on the aluminum evaporated thin layer. Evaporated to a thickness to form a silver deposited thin layer. Further, aluminum was added on the silver-deposited thin layer in an amount of 0.1 mm.
A thin layer of evaporated aluminum was formed to a thickness of 12 μm, and silver was further evaporated to a thickness of 0.02 μm on the thin layer of aluminum to form a thin silver layer. The resulting laminate is run in the longitudinal direction while stretching the polyethylene terephthalate film, which is a base film, by 10% in the longitudinal direction, while mechanically vibrating and simultaneously jetting ethanol, aluminum dispersed in ethanol. Thin-film atypical flat metal flakes were obtained in which a thin-film silver-deposited layer as a main component was almost entirely laminated on both surfaces thereof. Thinning (crushing) in ethanol and further using a homomixer
The thickness is 0.16 μm, and the average area of the uneven plane is 0.1
The value obtained by dividing by 6 μm was 120 [μm].

[0016]

According to the present invention, a dispersion of an atypical flat metal powder of a very thin metal vapor-deposited thin layer in a volatile organic solvent can be obtained. It can be used for inks such as writing inks and ink-jet inks which can be applied, and paints which can impart metal glittering with excellent hiding power to printing, drawing and painted surfaces. These applications are versatile and there are very many in the formulation, constitution and composition, but extra components other than the atypical flat metal powder and volatile organic solvent of the extremely thin metal-deposited thin layer of the present invention. Is a dispersion of an atypical flat metal powder of a metal-deposited thin layer in a volatile organic solvent, in which any prescription can be dealt with.

Claims (2)

[Claims] 1. An atypical flat metal powder having a thinned thin film having a metal-deposited thin layer mainly composed of at least one metal as a main component, wherein the thickness of the atypical flat metal powder is 0.03.
From 0.5 to 0.5 μm, the ratio of the area of the plane to the thickness of the thin film is 5 to 5 × 10 ⁶ [μm], and the thin film also has a deposited thin layer portion other than the main constituent components. An atypical flat metal powder dispersion comprising a powder and a volatile organic solvent. (2) forming on the base film one or more vapor-deposited thin layers of components other than the main constituent metal, and forming one or more vapor-deposited thin layers of a metal containing the main constituent metal on the layer; By mechanical peeling, injection of a volatile organic solvent, penetration, etc., the layers are peeled off, and a thin film having one or more metal thin layers including at least one of the main constituent metal metal thin layers is incorporated into the volatile organic solvent. A method for producing an atypical flat metal powder dispersion, wherein the thin film is dispersed as a thinned atypical flat metal powder.