JP4542770B2 - Manufacturing method of fine particle arrangement substrate and fine particle arrangement substrate obtained by the method - Google Patents

Description

  The present invention relates to a method for producing a fine particle-arranged substrate and a fine particle-arranged substrate obtained by the method. More specifically, the present invention is a method for efficiently and stably producing a substrate in which fine particles are regularly arranged in a predetermined pattern, which is useful for various optical applications, in a short time, and this method. It relates to a fine particle arrangement substrate obtained in (1).

In recent years, the technology that regularly deposits and arranges functional fine particles with controlled optical or thermal properties and shapes on a substrate is a basic technology for constructing next-generation optical functional elements and chemical sensors. Attention has been paid.
For example, a substrate with optically controlled fine particles arranged one-dimensionally on the surface can be used for optical waveguides, microlens arrays, laser arrays, optical couplers, optical isolators, optical collimators, etc. The substrate may be used for optical materials such as light diffusion, reflection, and diffraction, surface emitting lasers, flat microlens arrays, optical couplers, optical isolators, and optical collimators. Further, the substrate arranged in three dimensions can be used for photonic materials and the like.

As a method of regularly arranging fine particles in a hexagonal lattice or tetragonal lattice on a surface substrate in a short time, for example, containing two or more liquids having different vapor pressures and surface tensions, and Agglomerated fine particles are dispersed in a medium composed of a liquid mixture having a uniform composition, and the fine particle dispersion is cast on the substrate surface to form a liquid film, and a part of the medium is vaporized and removed from the liquid film. Thus, a method for producing a fine particle thin film is disclosed in which the fine particles are developed in a single layer or multiple layers on the surface of the substrate (see, for example, Patent Document 1). However, in this production method, unless the production conditions are controlled very strictly, the fine particles cannot be regularly arranged in a desired shape. Therefore, there is a disadvantage that it is difficult to obtain a fine-shaped fine particle arrangement. is there.
JP 2002-286932 A

  Under such circumstances, the present invention efficiently and stably manufactures a substrate in which fine particles are regularly arranged in a predetermined pattern on a surface, which is useful for various optical applications. It is an object of the present invention to provide a method and a fine particle arrangement substrate obtained by this method.

  As a result of intensive studies to achieve the above object, the inventors of the present invention inclined the substrate having a predetermined pattern of grooves formed on the surface and immersed one end of the substrate in the fine particle dispersion. The inventors have found that the object can be achieved, and have completed the present invention based on the findings.

That is, the present invention
(1) The fine particle dispersion is raised along the grooves of the substrate by inclining a substrate having grooves on the surface and immersing one end of the substrate in a fine particle dispersion containing fine particles and a liquid medium. The liquid medium is vaporized and the fine particles are arranged in the groove,
The fine particles are silica-based fine particles having an average particle size of 0.01 to 50 μm and a coefficient of variation of particle size distribution (CV value) of 5% or less,
The liquid medium is a liquid medium having a surface tension of 150 to 400 μN / cm at 20 ° C. and a boiling point of 30 to 180 ° C. under atmospheric pressure,
The substrate is selected from organic polymer compounds, glass, ceramics, metals, metalloids,
The depth of the groove on the surface of the substrate is 0.1 to 5 times the average particle size of the fine particles;
(2) The method according to the above item (1), wherein an inclination angle of the substrate when one end of the substrate having a groove on the surface is immersed in the fine particle dispersion is 60 ° or less,
(3) The method according to (1) or (2) above, wherein the fine particle dispersion contains a surfactant,
(4) Any of the above items (1) to (3), wherein the fine particles have a coating layer of a thermoplastic component or an uncured thermosetting component on the surface, and are heat-treated after being arranged to immobilize the fine particles. And (5) a fine particle arrangement substrate obtained by the method according to any one of (1) to (4) above,
Is to provide.

  According to the present invention, a method for efficiently and stably producing a substrate in which fine particles are regularly arranged in a predetermined pattern, useful for various optical applications, in a short time, and obtained by this method. The fine particle arrangement substrate can be provided.

In the method for producing a fine particle-arranged substrate of the present invention, fine particles are arranged in the groove by inclining a substrate having a groove on the surface and immersing one end in a fine particle dispersion containing fine particles and a liquid medium. The method is used.
The liquid medium constituting the fine particle dispersion (hereinafter sometimes referred to as a dispersion medium) has a surface tension at 20 ° C. of 150 to 400 μN / cm and a boiling point of 30 to 180 ° C. under atmospheric pressure. In particular, a liquid having a surface tension of 200 to 350 μN / cm and a boiling point of 40 to 130 ° C. is preferable. Specific examples of such liquids include methanol (240 μN / cm, 65 ° C.), ethanol (240 μN / cm, 78 ° C.), propanol (230-250 μN / cm, 82-97 ° C.), butanol (240 μN / cm, 82-117 ° C.), acetonitrile (320 μN / cm, 81 ° C.), methyl ethyl ketone (280 μN / cm, 80 ° C.), isobutyl acetate (260 μN / cm, 117 ° C.), 1-heptane (220 μN / cm, 94 ° C.), sulfide Examples include diethyl (350 μN / cm, 53 ° C.). In addition, as for the numerical value in said (), the former shows the surface tension in 20 degreeC, and the latter shows the boiling point under atmospheric pressure. The dispersion medium may be a single type or a mixture of two or more types of compatible liquids.
When these liquids are used as the liquid medium of the fine particle dispersion, it is not necessary to make the purity close to 100% by a purification operation such as distillation. preferable.

On the other hand, the type of fine particles constituting the fine particle dispersion is not particularly limited, and the arrangement of fine particles formed from various types such as inorganic, organic polymer, inorganic-organic hybrid particles, etc. It is appropriately selected according to the use of the substrate.
Examples of the inorganic particles include silica particles, alumina particles, titania particles, zirconia particles, iron oxide particles, and carbon. Examples of the organic polymer particles include polystyrene, polymethyl methacrylate, polyethylene terephthalate, Examples of the particles include polycarbonate, polyimide, polyacrylamide, benzoguanamine resin, benzoguanamine / melamine / formaldehyde resin, ABS resin, and AS resin.

  On the other hand, examples of inorganic / organic hybrid particles include methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, and butyltrimethoxy. Silane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-acryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, Dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldiisopropoxysilane, diethyldimethoxysilane, diethyldi Toxisilane, Dipropyldiethoxysilane, Dibutyldimethoxysilane, Diphenyldimethoxysilane, Diphenyldiethoxysilane, Divinyldimethoxysilane, Divinyldiethoxysilane, Methylethyldimethylsilane, Methylethyldiethoxysilane, Methylphenyldimethoxysilane, Methylphenyldiethoxy Mention may be made of polyorganosiloxane particles obtained by hydrolysis / condensation polymerization of organoalkoxysilanes such as silane, ethylphenyldimethoxysilane and ethylphenyldiethoxysilane.

  In the present invention, these fine particles may be used alone or in combination of two or more. The specific gravity of the fine particles is not particularly limited as long as the specific gravity of the fine particles is larger than that of the liquid medium used as the dispersion medium. However, if the specific gravity is too large, the sedimentation rate in the fine particle dispersion is too high, so It is difficult to obtain and fine particles may settle during operation. Therefore, the upper limit of the specific gravity is about 5.

  Furthermore, it is important that the fine particles can be dispersed in a dispersion medium, and therefore, the fine particles may be surface-treated so that they can be easily dispersed in the dispersion medium. As the surface treatment method, in the case of the inorganic particles, a method of surface treatment with a silane coupling agent can be used. In addition, the inorganic particles and organic particles are put into the organoalkoxysilane hydrolysis / condensation polymerization sol exemplified as a raw material of the inorganic organic hybrid particles, and the surface is coated with polyorganosiloxane, A method of forming a core / shell structure can be used.

  Furthermore, a coating layer of an adhesive component can be provided on the surface of the fine particles. Examples of the covering layer include a layer made of a thermoplastic resin or an uncured thermosetting resin. By providing such a coating layer of an adhesive component, the substrate on which the fine particles are arranged is heat-treated, so that the fine particles can be fixed to each other and the substrate and fixed with good adhesion. In the core / shell structure fine particles described above, the shell also has a function as an adhesive component.

The shape of the fine particles is not particularly limited, and may be any of monodispersed true spherical shape, saddle shape, isotropic polyhedron and the like. Moreover, the magnitude | size is about 0.01-50 micrometers normally in an average particle diameter, when it is spherical, Preferably it is 0.1-20 micrometers. The variation coefficient (CV value) of the particle size distribution is preferably 5% or less, more preferably 3% or less, and further preferably 2% or less.
The coefficient of variation (CV value) can be obtained from the following equation.
CV value (%) = (standard deviation of particle size / average particle size) × 100
In the present invention, silica-based fine particles having an average particle diameter of 0.01 to 50 μm and a CV value of 5% or less are particularly preferable.

In the present invention, the concentration of the fine particle dispersion varies depending on the specific gravity and particle size of the fine particles, but is usually about 0.1 to 5% by mass. In the case of silica-based particles having a particle size of about several μm, the amount is preferably about 1% by mass.
In addition, a surfactant can be added to the fine particle dispersion to adjust the dispersibility of the fine particles and the surface tension of the dispersion medium. The surfactant may be appropriately selected from known surfactants depending on the combination of the dispersion medium and fine particles used or the material of the substrate described later. The amount of the surfactant used is not particularly limited, but is usually about 0.001 to 1% by mass, preferably 0.005 to 0.5% by mass with respect to the dispersion medium.

  The material of the substrate used in the present invention is not particularly limited, and can be appropriately selected from organic polymer compounds, glass, ceramics, metals, metalloids and the like according to the use of the fine particle arrangement substrate to be formed. . Examples of the substrate material include organic polymer compounds such as polycarbonate, polyolefin, polyethylene, polyethylene terephthalate, acrylic resin, polymethylpentene, and epoxy resin, glass such as soda-lime glass, alkali-free glass, and quartz glass, alumina, zirconia, and the like. And metals and semi-metals such as ceramics, aluminum, titanium, and silicon. Depending on the material of the substrate, the type of dispersion medium and the type of surfactant are appropriately selected.

  In the present invention, a substrate having a groove formed on the surface is used as the substrate. As will be described later, the fine particle dispersion rises along the grooves and fine particles are arranged. Therefore, the groove pattern is not particularly limited, and is appropriately selected according to the desired arrangement pattern of the fine particles. The grooves may be provided in a straight line, a curved line, a single line, or a plurality of lines. When a plurality of rows are provided, the intervals between adjacent rows may be the same or different.

  The cross-sectional shape of the groove is not particularly limited, and examples thereof include a concave shape, a V shape, and a semicircular shape, and a V shape is particularly preferable. In the case of the V shape, the groove bottom angle is preferably 120 ° or less, more preferably 45 to 90 °, and particularly preferably around 60 °. Further, the groove width is preferably 10 times or less, more preferably 5 times or less, and further preferably 1 to 2 times the average particle diameter of the fine particles used. The groove depth is preferably about 0.1 to 5 times the average particle size of the fine particles, more preferably 0.5 to 3.0 times.

In the present invention, the method for forming the groove is not particularly limited, and can be appropriately selected from various methods according to the type of the material of the substrate. Specifically, methods such as injection molding, etching, photolithography, thermal transfer, and sol-gel embossing can be employed.
In the present invention, the substrate having the grooves provided on the surface in this manner is inclined, and one end of the substrate is immersed in the fine particle dispersion to raise the fine particle dispersion along the grooves of the substrate. After filling the inside of the groove, the dispersion medium is vaporized and fine particles are arranged in the groove.

  The inclination angle (immersion angle) of the substrate when one end of the substrate is immersed in the fine particle dispersion is not particularly limited, but is preferably 60 ° or less, and more preferably 5 to 45 °. Moreover, there is no restriction | limiting in particular about the immersion time of a board | substrate, and optimal time is selected by the size of a board | substrate and the formation pattern of a groove | channel. For example, if the size of the substrate is about 3 cm × 4 cm, about 3 to 10 minutes is preferable. Further, the immersion speed and the pulling speed are not particularly limited, but each is preferably about 1 mm / s.

The method for raising the fine particle dispersion along the grooves and evaporating the dispersion medium from the formed liquid film is not particularly limited, and optimum drying conditions are set according to the purpose.
In this way, by drying and vaporizing the dispersion medium, a substrate in which fine particles are regularly arranged along a groove having a predetermined pattern can be obtained. In addition, when fine particles coated with an adhesive component are used, the fine particles are fixed with good adhesion by drying at a suitable temperature according to the type of the adhesive component after drying. The

According to the method of the present invention, by forming grooves of a predetermined pattern on the substrate surface, the fine particles are arranged along the grooves. By selecting the groove pattern, the fine particles are regularly arranged in a desired pattern shape. The manufactured substrate can be manufactured stably.
The present invention also provides a fine particle arrangement substrate obtained by such a method of the present invention.
As the application of the fine particle arrangement substrate, the following applications can be considered depending on the shape and dimensions. For example, in the case of a one-dimensional arrangement, an optical waveguide, a microlens array, a laser array, an optical coupler, an optical isolator, an optical collimator, etc. can be considered. In the case of two-dimensional arrangement, optical materials such as light diffusion / reflection / diffraction, surface emitting lasers, flat-plate microlens arrays, optical couplers, optical isolators, optical collimators, and the like can be considered. Further, in the case of three-dimensional arrangement, by arranging and laminating fine particles so as to have crystallinity, functional materials such as photonic materials and low-temperature superplastic ceramics, micro pressure sensors, and the like can be considered.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
Example 1
(1) Preparation of fine particle dispersion liquid In a mixed medium (dispersion medium) having a mass ratio of water and ethanol of 1:99, silica fine particles (manufactured by Ube Nitto Kasei Co., Ltd., trade name “HI-PRECICA SS”, average particle size 10.0 μm, CV value 0.9%) was added to a concentration of 0.002% by mass and dispersed to prepare a fine particle dispersion.
(2) Fabrication of grooved substrate V-grooves having a width of 40 μm and a depth of 15 μm are arranged in parallel at intervals of 40 μm on a polymethylpentene substrate having a length of 40 mm, a width of 30 mm, and a thickness of 0.1 mm by a die pressing method. A plurality of substrates with grooves were prepared.
(3) Production of Fine Particle Arrangement Substrate The grooved substrate produced in (2) above is fixed to the jig 2 in FIG. 1 (reference numeral 1 is a fine particle dispersion, 2 is a jig for a substrate device, and 3 is a grooved substrate). Then, the substrate 3 was inclined so as to be 10 degrees with respect to the water surface of the fine particle dispersion 1, and one end thereof was slowly immersed in the fine particle dispersion at room temperature (25 ° C.) and atmospheric pressure. . Then, due to the surface tension (wetting property) of the dispersion medium to the substrate and the convection effect due to evaporation of the dispersion medium, the fine particle dispersion rises along the groove of the substrate, and at the same time, the fine particles move along the groove of the substrate. Arrange. The groove structure has an effect of increasing the contact area between the dispersion / substrate and promoting the flow of the dispersion.
In order to remove the dispersion medium remaining on the substrate by lifting the substrate from the fine particle dispersion after maintaining the state where one end of the substrate is immersed in the fine particle dispersion (at room temperature and atmospheric pressure) for 5 minutes, Air-dried.
(4) Observation of Fine Particle Arrangement State With respect to the substrate obtained in (3) above, the arrangement state of the fine particles was observed at a magnification of about several hundred to one thousand times using an optical microscope with a CCD camera. FIG. 2 shows this observation photograph. It was observed that fine particles were arranged along the grooves having a pitch of 40 μm.
Example 2
In the preparation of the fine particle dispersion of Example 1 (1), a nonionic surfactant (manufactured by Wako Pure Chemical Industries, Ltd., polyethylene glycol having an average molecular weight of 600) is added to the dispersion medium so as to be 0.01% by mass. Except for the above, the same operation as in Example 1 was performed to produce a fine particle arrangement substrate.
When this substrate was observed in the same manner as in Example 1 (4), it was found that fine particles were arranged in the same manner as in Example 1.
Example 3
(1) Preparation of fine particle dispersion 0.01% by mass diluted hydrochloric acid (using Wako Pure Chemical special grade) in ethanol (EtOH) solution of phenyltriethoxysilane [PhSi (OEt) ₃ ] (manufactured by Shin-Etsu Chemical Co., Ltd.) And a hydrolysis treatment was performed at room temperature for 2 hours. Next, this solution was poured into 4% by mass ammonia water (using Wako Pure Chemicals special grade) at a stretch, followed by further hydrolysis and polycondensation for 2 hours to obtain polyphenylsilsesquioxane (PhSi _3/2 ). A sol containing fine particles was prepared.
The composition of the sol solution was [PhSi (OEt) ₃ ]: EtOH: H ₂ O (water in dilute hydrochloric acid): H ₂ O (water in ammonia water) = 1: 4: 50: x in molar ratio. PhSiO _3/2 fine particles having an average particle diameter of about 1 μm with 50 ≦ x ≦ 100 could be produced.
From the obtained sol, only fine particles are separated at 1000 rpm at room temperature using a centrifuge (Pasolina small centrifuge), and dried at 50 ° C. for 3 hours using a dryer (manufactured by Yamato Kagaku). It was. The obtained fine particles were dispersed in ethanol to prepare a fine particle dispersion having a concentration of 1% by mass.
(2) Production of Fine Particle Arrangement Substrate Similar to Example 1 (3), using a glass grooved substrate in which a plurality of V-grooves having a width of 1.6 μm and a depth of 0.5 μm are provided in parallel at intervals of 1.6 μm. Thus, a fine particle placement substrate was produced.
(3) Observation of fine particle arrangement state The substrate obtained in (2) above was observed using an optical microscope and a field emission scanning electron microscope (manufactured by Hitachi, Ltd., FE-SEM-S4000). As in Example 1, it was found that particles were arranged in the groove.
Example 4
In Example 1, the same operation as in Example 1 was used except that a grooved polymethylpentene substrate in which a plurality of semicircular grooves having a radius of 20 μm were provided in parallel at intervals of 40 μm was used as the grooved substrate. The fine particle arrangement substrate was manufactured.
When this substrate was observed in the same manner as in Example 1 (4), it was found that it was arranged in the same manner as in Example 1.
Example 5
(1) Production of Fine Particle Arrangement Substrate In the preparation of the fine particle dispersion of Example 1 (1), silica fine particles coated with polystyrene resin on the surface instead of silica fine particles (trade name “HI-PRECICA N3P14” manufactured by Ube Nitto Kasei Co., Ltd.) And an average particle diameter of 5.2 μm, a resin coating thickness of 0.1 μm, a CV value of 1.7%), and a grooved substrate using glass instead of polymethylpentene. The same operation was performed to arrange fine particles in the groove of the substrate. Thereafter, heat treatment was performed in an oven at 120 ° C. for 2 hours to produce a fine particle-arranged substrate.
(2) Observation of arrangement state of fine particles When observation was performed in the same manner as in Example 1, it was found that the fine particles were arranged in the same manner.
In this state, the number of particles (number of particles A) was measured with an optical microscope (magnification 100 times). Thereafter, a dedicated nozzle (nozzle diameter: 1.5 mm) was installed under conditions of 45 ° and a distance of 10 mm, and after installation, nitrogen gas was blown from the nozzle at 0.1 MPa for 10 seconds to pull out particles. Thereafter, the number of particles (particle number B) was measured, the particle residual rate (%) [(B / A) × 100] was determined, and the fixing force was evaluated. As a result, the residual rate was 98%.
Example 6
(1) Preparation of silica particles having a shell / core structure To a ethanolic solution of phenyltriethoxysilane, 0.01% by mass of diluted hydrochloric acid is added and hydrolyzed at room temperature, and silica particles (Ube Nitto Kasei Co., Ltd.) Product name “HI-PRECICA SS”, average particle size 10.0 μm, CV value 0.9%), and further adding 4% by weight ammonia water, polyphenylsilsesquioxane is formed on the surface. Silica fine particles having a coated shell / core structure were prepared. The silica fine particles had an average particle diameter of 15 μm, and 2.5 μm of polyphenylsilsesquioxane was formed on the surface of the silica particles.
(2) Production of Fine Particle Arrangement Substrate Using the silica particles having the shell / core structure obtained in (1) above, fine particles were arranged in the grooves of the substrate in the same manner as in Example 5. Thereafter, heat treatment was performed in an oven at 300 ° C. for 2 hours to produce a fine particle-arranged substrate.
(3) Observation of the state of fine particle arrangement When observation was performed in the same manner as in Example 1, the polyphenylsilsesquioxane coated on the surface caused fusion, and the particles were adhered to each other. 5 was found to be arranged in the same manner.
In this state, the number of particles (number of particles A) was measured with an optical microscope (magnification 100 times). Thereafter, a dedicated nozzle (nozzle diameter: 1.5 mm) was installed under conditions of 45 ° and a distance of 10 mm, and after installation, nitrogen gas was blown from the nozzle at 0.1 MPa for 10 seconds to pull out particles. Thereafter, the number of particles (particle number B) was measured, the particle residual rate (%) [(B / A) × 100] was determined, and the fixing force was evaluated. As a result, the residual rate was 100%.
Comparative Example 1
In Example 1, instead of the grooved polymethylpentene substrate, the same operation as in Example 1 was carried out except that a polymethylpentene substrate without grooves was used to produce a fine particle arrangement substrate.
When this substrate was observed in the same manner as in Example 1, it was found that the fine particles were densely packed but were not arranged with directionality.

Industrial application fields

  According to the present invention, a substrate in which fine particles are regularly arranged on a surface in a predetermined pattern can be manufactured efficiently and stably in a short time. The fine particle arrangement substrate thus obtained can be expected to be used in various fields in the optical field.

In an Example and a comparative example, it is explanatory drawing which shows the method of immersing the end of a board | substrate in a fine particle dispersion. FIG. 3 is an observation photograph by an optical microscope showing an arrangement state of fine particles on a fine particle arrangement substrate obtained in Example 1.

Explanation of sign

1 Fine particle dispersion 2 Jig for substrate mounting 3 Substrate with groove

Claims (5)

A substrate having a groove on the surface is inclined in a fine particle dispersion containing fine particles and a liquid medium, and one end of the substrate is immersed, so that the fine particle dispersion is raised along the groove of the substrate. The liquid medium is vaporized and the fine particles are disposed in the groove,
The fine particles are silica-based fine particles having an average particle size of 0.01 to 50 μm and a coefficient of variation of particle size distribution (CV value) of 5% or less,
The liquid medium is a liquid medium having a surface tension of 150 to 400 μN / cm at 20 ° C. and a boiling point of 30 to 180 ° C. under atmospheric pressure,
The substrate is selected from organic polymer compounds, glass, ceramics, metals, metalloids,
A method for producing a fine particle-arranged substrate, wherein the depth of the groove on the surface of the substrate is 0.1 to 5 times the average particle diameter of the fine particles.   The method according to claim 1, wherein an inclination angle of the substrate when the one end of the substrate having a groove on the surface is immersed in the fine particle dispersion is 60 ° or less.   The method according to claim 1 or 2, wherein the fine particle dispersion contains a surfactant.   The method according to any one of claims 1 to 3, wherein the fine particles have a coating layer of a thermoplastic component or an uncured thermosetting component on the surface, and the fine particles are fixed by heat treatment after placement. . A fine particle-arranged substrate obtained by the method according to any one of claims 1 to 4.

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