JPH08155379A - Transfer method of fine particle film - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a method for transferring and attaching a fine particle film onto a solid secondary substrate, which is capable of transferring and attaching the fine particle film smoothly and uniformly. [Structure] A surface of a solid secondary substrate is activated by irradiation with energy rays or is subjected to a hydrophobic treatment to generate a hydrophobic surface. Alternatively, a specific binding ligand film is provided on the surface of the solid secondary substrate, or a thiol group is adsorbed on the surface of the solid secondary substrate to generate a denatured protein and transfer and attach the fine particle film. Alternatively, the ultrafine particles are irradiated with energy rays to generate active radicals and transfer-attach them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transferring and attaching a fine particle film to a solid secondary substrate. More specifically, the present invention relates to a method for depositing and transferring a fine particle film onto a solid substrate, which is useful as an electronic device, a sensor, a molecular element, a biocompatible material, etc. as various functional materials.

[0002]

2. Description of the Related Art Conventionally, the inventors of the present invention have studied the formation of a fine particle film for advanced development of next-generation functional materials. In this process, a method of forming a two-dimensional fine particle film having a film-like structure by aggregating nanometer-order and micron-order particles on a liquid surface or a solid substrate has been technically established. Further, studies are also underway on three-dimensionalization of the fine particle film by forming a multilayer structure.

However, although it is such a notable technological advancement, it is necessary to adhere and transfer the fine particle film formed on the liquid surface to the solid secondary substrate, which is a measure for this. As for the situation, the actual situation is that a satisfactory method has not been established. That is,
When the fine particle film developed on the liquid surface is transferred and attached to a solid secondary substrate, the surface of the solid secondary substrate must have adhesiveness or adhesiveness to the fine particle film to be transferred and attached. . If the particles of the fine particle film are large, the unevenness of the surface of the solid secondary substrate does not pose a problem. Therefore, by sticking an adhesive tape or applying an adhesive on the surface of the secondary substrate, adhesion and adhesion to the surface can be improved. It is possible to impart the property to transfer and attach the particle film. However, protein particles (1 nm to 100 nm) in which the particles forming the fine particle film are small
When transferring and adhering fine particles such as, the unevenness of the surface of the solid secondary substrate becomes a serious problem, and unless the surface is smooth, the treatment with an adhesive tape or an adhesive cannot be performed, and the fine particles may be transferred and adhered. It was actually difficult.

Therefore, the present invention was devised to solve the above-mentioned drawbacks of the prior art, and an object thereof is to provide a new method for transferring and attaching a fine particle film.

[0005]

As a solution to the above problems, the present invention is a method for adhering and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface onto a solid secondary substrate. Provided is a method for transferring and attaching a fine particle film, which comprises activating the surface of a solid secondary substrate by irradiation with energy rays to attach the fine particle film.

Furthermore, according to the present invention, the surface of the solid secondary substrate is subjected to a hydrophobic treatment to form a hydrophobic surface (hydrophobic film) for transfer and adhesion, and a specific binding ligand film is formed on the surface of the solid secondary substrate. To generate and transfer and attach, to generate and transfer and attach denatured protein adsorbed on the surface of a solid secondary substrate, and to irradiate fine particles with energy rays to generate active radicals and transfer and attach. Also provided is a method of transferring and depositing a featured particulate film.

[0007]

In the present invention, the surface of the solid secondary substrate is activated by UV irradiation, plasma treatment in vacuum, or ion sputtering treatment, for example, by the means as described above. It can be converted into an active surface, and the fine particle film can be transferred and attached to the active surface.

Further, a hydrophobic surface (hydrophobic film) of the solid secondary substrate is generated by subjecting the surface of the solid secondary substrate to a hydrophobic treatment, and a fine particle film is transferred and attached onto the hydrophobic surface (hydrophobic film) by hydrophobic bonding. can do. Furthermore, a ligand film is formed by uniformly adhering a specific binding ligand such as an antibody, azetin, streptazetin or the like on the surface of the solid secondary substrate, and the solid film is formed by binding with the ligand film.
A fine particle film such as protein particles having the same specific binding ligand as the ligand attached to the surface of the next substrate can be transferred and attached.

Alternatively, a denatured protein adsorbed by a thiol group or the like is arranged on the surface of the solid secondary substrate, and the cysteine residue, which is a site where the surface of the solid secondary substrate comes into contact with the fine particles is genetically engineered by this denatured protein. The fine particles can be transferred and attached by introducing them selectively. Furthermore, by irradiating the fine particles with an energy ray such as UV to generate active radicals, and using the active radicals in the attachment reaction, the fine particle film can be transferred and attached to the solid secondary substrate.

In the present invention, of course, the type of the fine particles is not particularly limited, and may be an organic polymer, a polymer substance such as a natural or synthetic protein, a ceramic, a metal, or a complex thereof. Depending on the type, the means of adhesion transfer will be selected. Also, the size of the fine particles is
It can be nanometer or micrometer fine particles. The film of these fine particles to be subjected to the adhesion transfer may have a structure in which the fine particles are two-dimensionally aggregated, or a three-dimensional integrated structure thereof.

Various types of solid secondary substrates are also adopted. For example, it may be the surface of a semiconductor such as silicon, metal, graphite, a carbon film, glass, other ceramics, organic polymers, wood, fibers and the like. Regarding the fine particle film itself, a fine particle dispersed in a two-dimensional manner by spreading the fine particle dispersion on the surface of mercury, water, or other organic solvent and removing the dispersion medium by evaporation, suction, or the like, or The crystallized structure and those three-dimensional structures can be appropriately targeted.

[0012]

EXAMPLES The present invention will be described in more detail below with reference to examples. Of course, the present invention is not limited to the following examples. Example 1 FIG. 1 shows polystyrene fine particles (average particle size of about 4) transferred and attached to a carbon film subjected to ion sputtering treatment.
(0 nm) is a transmission electron microscope image of the film. FIG. 2 shows a transmission electron microscope image of a film of ferritin protein particles (average particle size 20 nm) transferred and attached to a carbon film that has been subjected to an ion sputtering treatment.

In any case, first, a thin carbon film is formed by vacuum-depositing carbon on a freshly cleaved mica surface, and the carbon film is separated from the mica surface on the distilled water surface to form a copper mesh. Scoop on top. Ion sputtering is performed on the surface of the scooped carbon film by Ar (argon) ions according to a conventional method. Immediately after the ion sputtering process,
The carbon film is pressed from above for a few seconds to a few minutes onto the fine particle film developed on the surface of a liquid such as mercury, water, or an organic solvent to transfer and adhere the ultrafine particle thin film to the carbon film which is the solid secondary substrate. Of course, it is possible to transfer and attach Si or graphite to a solid secondary substrate instead of the carbon film. Example 2 FIG. 3 shows an image of a scanning electron microscope of a protein particle film transferred and attached by hydrophobic bonding to a Si substrate that has been subjected to a hydrophobic treatment.

That is, the Si substrate, which is a solid secondary substrate, is dipped in a 1-20% HF aqueous solution and the thin SiO ₂ coating is stripped off to perform a hydrophobic treatment. The hydrophobic surface and the protein particle film are hydrophobically bound by pressing the exposed Si surface, that is, the hydrophobic surface of the Si substrate, against the ferritin protein particle film spread on the water surface from above for several seconds to several minutes. Transfer and attach. Example 3 FIG. 4 shows an image of a scanning electron microscope of a ferritin protein particle film transferred and attached by a hydrophobic bond to a polypyrrole film electropolymerized on ITO glass by a hydrophobic treatment.

That is, first, ITO glass, which is an electrode for forming a polypyrrole film, and platinum, which is a reference electrode, are immersed in a dilute aqueous solution of pyrrole, and a DC voltage of 1.2 V or less is applied to this electrode to effect electric field polymerization. To do. By this electric field polymerization, a polypyrrole film which is a hydrophobic film is formed on the ITO glass. The produced polypyrrole film thickness is adjusted by the concentration of the pyrrole aqueous solution and the application time of the DC voltage.
After the polypyrrole film is sufficiently dried, the polypyrrole film is pressed against the ferritin protein particle film developed on the water surface from above for a few seconds to a few minutes to be hydrophobically bonded and transfer-attached. As the electrode for forming the polypyrrole film (hydrophobic film), not only the ITO film but also a conductive material such as gold or platinum can be used. Example 4 FIG. 5 shows a scanning electron microscope image of a polystyrene particle film transferred and adhered to the hydrophobic surface of the casein film adhered on the glass surface by the hydrophobic treatment.

That is, first, casein, which is a polymer having both a hydrophilic group and a hydrophobic group in the same chain, and which has surface chemical properties is spread on the water surface, and the spread casein film is used as a surface of a hydrophilic solid (glass). The hydrophobic surface of the casein film is exposed by adhering it onto the surface by pulling up. The hydrophobic surface of the casein film on the glass surface is pressed against the polystyrene particle film developed on the water surface from above for several seconds to several minutes to cause hydrophobic bonding and transfer and attachment of the polystyrene particle film.

[0017]

As described in detail above, according to the present invention, it is possible to smoothly and uniformly transfer and attach a fine particle film to a solid substrate without being limited to the above example.

[Brief description of drawings]

FIG. 1 is a photograph replacing a drawing of a transmission electron microscope image (TEM image: accelerating voltage 100 kV, direct observation) of a polystyrene particle film transferred and attached to a carbon film that has been subjected to an ion sputtering treatment.

FIG. 2 is a photograph replacing a drawing of a transmission electron microscope image (TEM image: accelerating voltage 100 kV, uranyl acetate stain) of a protein particle film transferred and attached to a carbon film subjected to ion sputtering treatment.

FIG. 3 is a scanning electron microscope image (S) of a protein particle film transferred and attached by hydrophobic bonding to a Si substrate that has been subjected to a hydrophobic treatment.
EM image: acceleration voltage 1 kV, direct observation).

FIG. 4 is a scanning electron microscope image (SEM image: accelerating voltage 1) of a protein particle film transferred and attached by hydrophobic bonding to a polypyrrole film electropolymerized on ITO glass by a hydrophobic treatment.
kV, direct observation).

FIG. 5 is a photograph replacing a drawing of a scanning electron microscope image (SEM image: accelerating voltage 1 kV, direct observation) of a polystyrene particle film transferred and attached to a hydrophobic surface of a glass film attached to a glass surface by a hydrophobic treatment. Is.

Claims (5)

[Claims] 1. A method of adhering and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface to a solid secondary substrate, wherein the surface of the solid secondary substrate is activated by irradiation of energy rays. A method for transferring and attaching a fine particle film, which comprises depositing 2. A method for depositing and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface onto a solid secondary substrate, wherein the surface of the solid secondary substrate is subjected to a hydrophobic treatment to form a hydrophobic surface. And then depositing the fine particle film. 3. A method of adhering and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface to a solid secondary substrate, wherein a specific binding ligand film is provided on the surface of the solid secondary substrate. Then, a method for transferring and attaching a fine particle film, which comprises depositing a fine particle film next. 4. A method for depositing and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface onto a solid secondary substrate, wherein a denatured protein film adsorbed on the surface of the solid secondary substrate is provided. Then, a method for transferring and attaching ultrafine particles, which comprises depositing a fine particle film. 5. A method of depositing and transferring a fine particle film produced from a fine particle dispersion liquid spread on a liquid surface onto a solid secondary substrate, wherein fine particles are irradiated with energy rays to generate active radicals, and then fine particles are generated. A method for transferring and attaching ultrafine particles, which comprises depositing a film.