JP2006150340A - Metallic film, production method of metallic film, emulsification method, particulate and membrane emulsification apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To produce a diaphragm at a low cost which is used in a membrane emulsification apparatus in which even a particulate of minute grain size can be produced, grain size of obtained particulates is uniform, particulates with uniform dispersion can be produced even when the particulate includes solid content and maintenance is easy, which is easy to handle and has little fear of breakage. <P>SOLUTION: Dispersion layers are dispersed in a continuous layer by using a metallic membrane, which is made of a metallic base material and has two or more mutually independent through holes of the same shape and whole exposed surface of which has specific opening shape of high hydrophilicity or of high hydrophobicity, as the diaphragm. This metallic membrane is produced as following, for example. An insulated layer 2 is formed on an electric conductive substrate 1, a part thereof is selectively removed to expose the electric conductive substrate 1 and electroplating is performed by using the exposed substrate as a cathode. As a plated coating film 3 grows, it is pushed out on the insulated layer to form an insulated layer opening 4. Metal plating is finished before the insulated layer opening is completely covered and the plated coating film is separated from the electric conductive substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to emulsions and fine particles, particularly those containing a solid content therein and a manufacturing apparatus thereof, fine particles such as spacers, toner, and microcapsules for electronic paper, a method for forming the same, and a metal having a unique opening shape used therefor The present invention relates to a film and a method for forming the film.

Even substances that are not inherently mixed, such as water and oil, can be made into an apparently mixed state by dispersing one substance as fine particles. This phenomenon is called emulsification. Yes. In order to maintain such a state, it is necessary that the dispersed particles have a small diameter and are relatively uniform.
It is publicly known that the following methods are specifically used as an emulsification method.
(1) Emulsification by a homogenizer [Matsumoto Yushi Seiyaku Co., Ltd. (for example, refer to Patent Document 1)] This is a method in which a substance to be finely dispersed is added to a liquid called a continuous phase and mechanically stirred. A shearing force is repeatedly applied to obtain an emulsified dispersion.
(2) Emulsification using a porous glass membrane [Miyazaki Prefecture (for example, see Patent Document 2) etc.]
The dispersed phase and continuous phase are separated by a porous glass membrane, and the dispersed phase passes through the membrane by extruding the dispersed phase to the continuous phase side. This is a method for obtaining an emulsified dispersion.
(3) Emulsification using partition walls with artificially formed micro openings [Food Research Institute (for example, see Patent Document 3), etc.]
The dispersed phase and the continuous phase are partitioned by a partition wall in which a large number of non-circular openings having the same shape are artificially formed by a semiconductor process, and the dispersed phase is extruded to the continuous phase through the openings to obtain fine particles. At this time, since the opening shape is non-circular such as a slit shape, it can be easily sheared due to the non-uniform surface tension, and particles having a small particle size distribution can be obtained.
Japanese Patent No. 3476223 Japanese Patent No. 2733729 Japanese Patent No. 3511238

However, in the prior art (1), the shearing force applied to the dispersed phase is not uniform depending on the emulsifying position, and thus the obtained particles have a wide particle size distribution.
Moreover, in (2), the hole shape of the porous glass film is composed of a relatively smooth continuous curve, and the surface tension acting on the extruded interface works relatively uniformly, so that it does not easily shear. The resulting particle size will be larger than the opening. Further, since the hole shape and size are not constant, the particle size distribution is narrower than the method (1) but relatively wide.
In (3), the opening of the disclosed partition wall is a parallel through hole whose cross-sectional shape does not change with respect to the thickness direction of the partition wall. It is thought that it becomes difficult to extrude into a continuous phase when a high viscosity material is used. Conversely, when the partition walls are made thinner, extrusion becomes relatively easy, but problems such as deformation or destruction of the partition walls due to the pressure applied during extrusion can be considered.
In view of the above problems, the present invention can produce fine particles that can be produced even with a fine particle size, and even when the obtained particle size is uniform and contains a solid content therein, the dispersion is uniform. It is an object of the present invention to provide a membrane emulsification apparatus that is easy to maintain and a method for inexpensively producing a diaphragm that is easy to handle and less likely to break.
Another object of the present invention is to provide a metal film that can easily move the fluid required for emulsification and that can apply a non-uniform shear force to the fluid, a method for producing the metal film, and a particle size distribution using the metal film. It is to provide a small particle and a manufacturing method thereof.

In order to achieve the above object, the invention described in claim 1 is characterized in that it is made of a metal base material, has two or more through-holes of the same shape independent from each other, and the entire exposed surface has a highly hydrophilic surface. And
According to a second aspect of the present invention, in the metal film according to the first aspect, the openings having the same shape are formed so as to face the same direction.
The invention described in claim 3 is an index value F1 indicating that the metal film according to claim 1 or 2 has a smaller side when the opening shape of the front and back of the through hole is different, and when the opening shape is equal, the shape is the same. (F1 = (absolute maximum length) ^ 2 / area × π / 4) and the index value F2 (F2 = 4π × area / (circumference length) ^ 2) satisfy the relationship of F1 ≧ 2 and F2 ≦ 0.8. It is characterized by doing.
According to a fourth aspect of the present invention, in the metal film according to any one of the first to third aspects, the width on one side surface is W1 and the width on the other side surface in any cross section in the film thickness direction of the through hole. When W2, the relationship of W1 ≧ W2 is satisfied, and there is no portion whose width is larger than W1 and smaller than W2 at any place in the thickness direction.
According to a fifth aspect of the present invention, in the metal film according to any one of the first to fourth aspects, the shortest distance from one surface of the through hole to the other surface is equal to the film thickness around the through hole. It is characterized by being.
According to a sixth aspect of the present invention, in the metal film according to any one of the first to fifth aspects, in the cross section in the film thickness direction of the through hole, the width on one side surface is W1, and the width on the other side surface is W2. When satisfying the relationship of W1 ≧ W2, the position in the thickness direction on the surface where the width is W1 is 0, and the thickness of the surface where W2 is T is T, the arbitrary positions T1, T2 in the thickness direction , T3 (0 <T1 <T2 <T3 <T) and the widths WT1, WT2 and WT3 at the position are WT1 = WT2 = WT3 or (WT1-WT2) / (T2-T1) ≧ (WT2-WT3) / (T3-T2).
The invention according to claim 7 is characterized in that it is made of a metal base material, has two or more through-holes of the same shape independent from each other, and the entire exposed surface has a highly hydrophobic surface.
According to an eighth aspect of the present invention, in the metal film according to the seventh aspect, the openings having the same shape are formed so as to face in the same direction.
The invention according to claim 9 is the metal film according to claim 7 or 8, wherein when the opening shape of the front and back of the through hole is different, the smaller side, and when the opening shape is equal, the shape is an index value F1 ( F1 = (absolute maximum length) ^ 2 / area × π / 4) and index value F2 (F2 = 4π × area / (circumference length) ^ 2) satisfy the relationship of F1 ≧ 2 and F2 ≦ 0.8. It is characterized by that.
A tenth aspect of the present invention is the metal film according to any one of the seventh to ninth aspects, wherein the width on one side surface is W1 and the width on the other side surface is any cross section in the film thickness direction of the through hole. When W2, the relationship of W1 ≧ W2 is satisfied, and there is no portion whose width is larger than W1 and smaller than W2 at any place in the thickness direction.

The invention according to claim 11 is the metal film according to any one of claims 7 to 10, wherein the shortest distance from one surface of the through hole to the other surface is the film thickness around the through hole. It has the same shape.
In the invention according to claim 12, in the metal film according to any one of claims 7 to 11, the width on one surface is W1 and the width on the other surface is W2 in the cross section in the film thickness direction of the through hole. Sometimes when the relationship of W1 ≧ W2 is satisfied, the position in the thickness direction on the surface where the width is W1 is 0, and the thickness of the surface where W2 is T is arbitrary position T1, T2, The relationship between T3 (0 <T1 <T2 <T3 <T) and the widths WT1, WT2, and WT3 at that position is WT1 = WT2 = WT3 or (WT1-WT2) / (T2-T1) ≧ (WT2-WT3) / (T3-T2).
The invention according to claim 13 is a first step of preparing a substrate having conductivity on at least a surface thereof, a second step of covering the surface of the conductive substrate with an insulating film, and partially the insulating film. And a third step of exposing the conductive surface, and an electroplating layer having a predetermined film thickness that does not cover the entire insulating layer more than the insulating film with respect to the substrate on which the conductive surface is partially exposed In a method for producing a metal film having through-holes with different sizes on the front and back, comprising a fourth step of forming and a fifth step of separating the metal film obtained by electroplating from the substrate, Assuming that the thickness of the insulating film formed in the second step is ti and the thickness of the electroplating layer formed in the fourth step is T, as a result of being partially removed by the third step, The shape of the remaining insulating film is the shape of the opening to be formed in the metal film. Characterized in that the smaller opening shape of the area is separated shape distance (T-ti) on the outside.
The invention according to claim 14 is a first step of preparing a conductive substrate, a second step of covering the surface of the conductive substrate with an insulating layer, and an array having a polygon having three or more vertices in the insulating layer Forming a group of one or more insulating layer openings and exposing the conductive substrate in each insulating layer opening, and performing electroplating with the conductive substrate having the insulating layer opening formed as a cathode. A fourth step of forming a plating film in such a range that precipitates from adjacent insulating layer openings in the insulating layer opening group are in contact with each other and a non-deposition portion remains in the central portion of the array, and the conductive substrate and the plating film And at least a fifth step of separating.

A fifteenth aspect of the invention is characterized in that in the metal film manufacturing method according to the thirteenth or fourteenth aspect, a step of covering the metal film surface with a hydrophilic film is performed as a sixth step after the fifth step. .
A sixteenth aspect of the invention is characterized in that, in the metal film manufacturing method according to the fifteenth aspect, the step of covering with the hydrophilic film is performed by thermal oxidation.
The invention according to claim 17 is the method for producing a metal film according to claim 16, characterized in that the step of covering with the hydrophilic film is subjected to thermal oxidation and further the step of forming the hydrophilic film.
The invention according to claim 18 is the method for producing a metal film according to claim 13 or 14, wherein a step of covering the surface of the metal film with a hydrophobic film is performed as a sixth step after the fifth step. And
A nineteenth aspect of the invention is characterized in that a dispersed phase is extruded into a continuous phase through the metal film according to any one of the first to twelfth aspects.
The invention of claim 20 is characterized by being formed by the emulsification method of claim 19.
The invention of claim 21 includes at least a continuous phase accommodating portion, a dispersed phase accommodating portion, a diaphragm having a plurality of minute through holes separating the continuous phase accommodating portion and the dispersed phase accommodating portion, and the continuous phase accommodating portion. A continuous phase supply unit for supplying a continuous phase, a dispersed phase supply unit for supplying a dispersed phase to the dispersed phase storage unit, and a discharge unit for taking out the emulsion produced in the continuous phase storage unit. In the membrane emulsification apparatus provided, the metal film according to any one of claims 1 to 12 is used as the diaphragm, and the absolute maximum length on one side surface of the through-hole formed in the metal film is W1, and the other side When the absolute maximum length on the surface is W2, the surface that becomes W1 in the relationship of W1 ≧ W2 is arranged on the dispersed phase accommodating portion side, and the surface that becomes W2 is arranged on the continuous phase accommodating portion side. .

In the metal film according to claim 1, since the entire exposed surface has a highly hydrophilic surface, when this is used as a diaphragm, an aqueous medium is used as a continuous phase and an oil-based medium is used as a dispersion layer, an oil-in-water emulsification is performed. In addition, it is possible to reduce problems caused by the dispersed phase adhering to the diaphragm. In addition, since the diaphragm is made of metal, there is no risk of cracking even if it is thin, and handling is easy, and even when a problem occurs, it can be easily handled. Furthermore, since the formed through-holes are independent from each other, the flow of the continuous phase is in a fixed direction, and even when a continuous phase containing solid content is used, problems such as solids staying and adhering can be reduced. Can be blocked.
Since the metal film according to the second aspect is formed so that the openings are directed in the same direction, portions where the surface tension applied to the flowing fluid is maximized can be aligned in the same direction.
In the metal film according to the third aspect, since the shape of the formed through hole is a shape suitable for particle generation, particles having a small diameter with respect to the size of the through hole can be generated with a uniform particle size.
The metal film according to claim 4 has no portion where the width of the cross-section of the formed through-hole is wider than the surface in contact with the dispersed phase, so there is no portion where the speed decreases in the flow of the continuous phase, and the blockage of the through-hole is further effective Can be deterred.
In the metal film according to claim 5, the shortest distance in the film thickness direction of the formed through hole is equal to the film thickness, that is, the continuous phase passes through a linear path, so that the block of the through hole can be further suppressed and the fluid resistance is also reduced. Since it can be reduced, a highly viscous liquid can be used for the dispersed phase.
In the metal film according to claim 6, the reduction ratio of the width of the cross-section of the formed through hole is the smallest in the vicinity of the surface in contact with the continuous phase, and the influence on the particle diameter at which the variation of the splitting position during particle formation is obtained. Can be reduced.

In the metal film according to claim 7, since the entire exposed surface has a highly hydrophobic surface, this is used as a diaphragm and an oil-based medium is used as a continuous phase, and an aqueous medium is used as a dispersion layer to perform water-in-oil emulsification. In this case, it is possible to reduce problems caused by the dispersed phase adhering to the diaphragm. In addition, since the diaphragm is made of metal, there is no risk of cracking even if it is thin, and handling is easy, and even when a problem occurs, it can be easily handled. Furthermore, since the formed through-holes are independent from each other, the flow of the continuous phase is in a fixed direction, and even when a continuous phase containing solid content is used, problems such as solids staying and adhering can be reduced. Can be blocked.
Since the metal film according to the eighth aspect is formed so that the openings are directed in the same direction, the portions where the surface tension applied to the flowing fluid is maximized can be aligned in the same direction.
In the metal film according to the ninth aspect, since the shape of the formed through hole is a shape suitable for particle generation, particles having a small diameter with respect to the size of the through hole can be generated with a uniform particle size.
The metal film according to claim 10 has no portion where the width of the cross-section of the formed through-hole is wider than the surface in contact with the dispersed phase, so there is no portion where the speed decreases in the flow of the continuous phase, and the through-hole is more effectively blocked. Can be deterred.
In the metal film according to claim 11, the shortest distance in the film thickness direction of the formed through hole is equal to the film thickness, that is, the continuous phase passes through a linear path, so that the blocking of the through hole can be further suppressed and the fluid resistance is also reduced. Since it can be reduced, a highly viscous liquid can be used for the dispersed phase.
In the metal film according to claim 12, the reduction ratio of the width of the cross-section of the formed through-hole is the smallest in the vicinity of the surface in contact with the continuous phase, and the influence on the particle diameter at which the variation of the splitting position during particle formation is obtained. Can be reduced.
In the method for producing a metal film according to claims 13 and 14, since it is formed by electroplating, it is possible to uniformly produce a film thickness that can be used as a single film by an inexpensive means. Since the shape considering the growth is defined as the shape of the insulating film, the desired through-hole shape can be obtained, and the metal film according to any one of claims 1 to 12 can be manufactured.

Since the method for producing a metal film according to claim 15 includes a step of covering with a hydrophilic film, the metal film having a hydrophilic surface according to any one of claims 1 to 6 can be produced.
In the method for producing a metal film according to claim 16, since the step of covering with a hydrophilic film is performed by thermal oxidation, a hydrophilic film with good adhesion can be easily and reliably formed to the inside of the through hole. The metal film which shows the hydrophilic surface in any one of Claim 1 to 6 can be manufactured.
In the method for producing a metal film according to claim 17, since a hydrophilic film having good adhesion is reliably formed to the inside of the through-hole by thermal oxidation, the hydrophilic film is further formed by another method. The metal film which shows the hydrophilic surface in any one of Claim 1 to 6 can be manufactured.
Since the method for producing a metal film according to claim 18 includes a step of covering with a hydrophobic film, the metal film having a hydrophobic surface according to any one of claims 7 to 12 can be produced.
In the emulsification method according to claim 19, since the emulsification is performed through the metal film, a highly viscous fluid can be used, and a constant portion where the surface tension is maximized can be formed. Emulsification can be performed.
The fine particles according to claim 20 are uniform in size.
Since the membrane emulsification apparatus according to claim 21 uses the metal film according to any one of claims 1 to 12, it is possible to produce fine particles having a uniform particle diameter even when solid content is included. Also, maintenance is easy.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic view of a film emulsification apparatus provided with a metal film in the present invention. The dispersed phase accommodating part 20 and the continuous phase accommodating part 21 are separated by a diaphragm 23 in which a through hole 22 is formed. The dispersed phase storage unit 20 has a dispersed phase supply port 24, which is connected to a dispersed phase supply system for supplying a dispersed phase (not shown). Further, the continuous phase container 21 has a continuous phase supply port 25 and a discharge port 26 for recovering the produced emulsion and particles, and the continuous phase supply port 24 is connected to a continuous phase supply means (not shown). Is connected to a collecting means (not shown). In a state where the continuous phase is supplied from the continuous phase supply port 25 and discharged from the discharge port 26, the dispersed phase is introduced through the through holes 22 provided in the diaphragm 23 by introducing the dispersed phase from the dispersed phase supply port 24. It moves into the continuous phase, spheroidizes due to the influence of the interfacial tension with the continuous phase, and separates in the through-holes to form particles in the continuous phase. The generated particles are discharged from the discharge port 26 together with the continuous phase and collected. At this time, since the surface of the diaphragm is highly wettable with respect to the continuous phase, the surface in contact with the continuous phase accommodating portion 21 is in contact with the continuous phase, so that the dispersed phase does not contact the diaphragm in the continuous phase accommodating portion 21 and penetrates. A small particle size can be generated with respect to the hole 22. However, when the dispersed phase is excessively supplied, the dispersed phase is difficult to separate in the through-holes and grows large, resulting in a state where the dispersed phase is in contact with the surface of the diaphragm. In many cases, if the surface of the diaphragm is highly wettable with respect to the continuous phase, it can be restored to the initial state by reducing or stopping the supply amount of the dispersed phase, and set again to the appropriate supply amount of the dispersed phase. The production of the target particles can be resumed. However, the wettability with respect to the continuous phase of the diaphragm is insufficient, or even if the wettability is sufficient, a state in which a dispersed phase is attached in the vicinity of the through hole 22 on the surface of the diaphragm rarely occurs. In such a state, as shown in FIG. 2, the particles generated from the through-holes 22 become larger in diameter and need to be removed from the apparatus and cleaned in order to recover. In such a case, since the diaphragm 23 is made of a metal base material, it can be used for a long period of time with little risk of breakage during removal or cleaning.
In the emulsification apparatus using the metal film of the present invention when forming particles containing solid content such as solid fine particles inside, the through holes 22 formed in the diaphragm 23 are independent of each other, and therefore, as shown in FIG. When the dispersed phase 27 is obtained by uniformly dispersing fine particles, branching, merging or the like does not occur in the process of passing through the through-holes 22, so that particles in a state adjusted as a dispersed phase are generated.

The state of particle generation will be described with reference to FIG. FIG. 11 schematically shows the particle generation process in three stages, each showing one through-hole as viewed from directly above the continuous phase side, and the cross-section and through-hole at the contact point between the through-hole and the inscribed circle. It consists of a cross section at the contact point between the hole and the circumscribed circle. First, as shown in FIG. 11 a), the dispersed phase 27 advances through the through hole 22. Subsequently, as shown in b), a part of the through hole 22 is extruded toward the continuous phase. At this time, since the dispersed phase 27 is deformed to become spherical due to the interfacial tension with the continuous phase, the dispersed phase immediately behind it has a circular cross-sectional shape having a smaller diameter than the dispersed phase substantially spheroidized in the continuous phase. Further, in the rear through hole, the liquid column is constrained by the shape of the through hole. After that, as shown in c), the spherical dispersed phase 27a in the continuous phase and the dispersed phase constrained by the shape of the through-holes 22 are distorted to generate dispersed phase particles in the continuous phase. By repeating this operation, particle generation is continuously performed. At this time, if the shape of the through-hole is close to a circle, the distortion generated at the connecting portion between the tip particle and the continuous phase in the through-hole is small, so that it is difficult to break up, the generated particle size increases, and the variation Will be big. As a result of examining the relationship between the opening shape and the obtained particles, it was found that a shape that can provide good results can be defined by two index values. The first index value F1 is F1 = (absolute maximum length) ^ 2 / area × π / 4.
In the case of a perfect circle, F1 = 1, and the greater the distance from the circle, the greater the number. The second index value F2 is F2 = 4π × area / (circumference length) ^ 2.
In the case of a perfect circle, F2 = 1 and the smaller the circle, the smaller the number.
When these two index values have a shape satisfying the relationship of F1 ≧ 2 and F2 ≦ 0.8, a uniform particle size variation obtained by stably and continuously generating particles was obtained. A part of a specific through hole diameter shape and a region satisfying two indices in the shape are illustrated in FIGS. 12 to 16, but the shape is not limited to these shapes as long as the above conditions are satisfied. 12A to 16A show the shape, and FIG. 12B shows the relationship between the index values F1 and F2.

The cross-sectional shape of the through-hole formed in the metal film used in the emulsifying device of the present invention is as follows. When the cross-sectional width of the opening in contact with the dispersed phase is W1, and the cross-sectional width of the opening in contact with the continuous phase is W2. It is desirable that W1 ≧ W2 and that the cross-sectional width is W1 maximum and W2 minimum in the film thickness direction. By making the through-hole of such a cross section, the dispersed phase moving in the through-hole moves to the continuous phase side without reducing its speed, so that the substance dispersed in the dispersed phase stays in the through-hole. This can be effectively prevented, the concentration in the generated particles can be made uniform, and solid substances can be prevented from adhering to the through holes and blocking of the through holes due to the solid substances. Specific examples of the shape include shapes shown in FIGS. In addition, this is the shape of one cross section, and it is only necessary to satisfy the above relationship even if each shape is different depending on how the cross section is cut out.
Further, it is more desirable that the through hole has the shortest distance equal to the peripheral film thickness, that is, formed in a direction perpendicular to the film surface. By adopting such a shape, it is possible to minimize the distance that the dispersed phase moves in a narrow space, and thus it is possible to more effectively prevent the through hole from being blocked. Moreover, a liquid with a high viscosity can be used as a continuous phase.
Further, in the cross-sectional shape of the through-hole, in more detail, the thickness direction of the diaphragm in which the through-hole is formed is arbitrary in the thickness direction when the surface in contact with the dispersed phase is 0 and the thickness of the diaphragm is T. The relationship between the cross-sectional widths WT1, WT2, and WT3 at the positions T1, T2, and T3 (0 ≦ T1 ≦ T2 ≦ T3 ≦ T) is WT1 = WT2 = WT3 or (WT1-WT2) / (T2-T1) ≧ (WT2- It is desirable to satisfy the relationship of WT3) / (T3-T2). Such a shape satisfying the former relationship is a shape whose width does not change in the thickness direction in any cross section of the through hole as shown in FIG. When the cross-sectional width of the shape satisfying the latter relationship is wider on the dispersed phase side than on the continuous phase side, the narrowing of the width becomes constant (FIG. 9) or becomes gentler toward the continuous phase side (FIG. 10). In such a shape, since the amount of variation in the cross-sectional area of the through hole in the vicinity of the continuous phase is the smallest, it is possible to reduce the influence on the volume and size of the particles obtained by changing the position of splitting during particle generation. And uniform size particles can be obtained.
The emulsifying device of the present invention is characterized in that the diaphragm having a through hole used therein is a metal base material. As a method of manufacturing this diaphragm, it is possible to remove metal thin films by etching or laser irradiation. However, a method combining photolithography and electrodeposition is suitable as a method for obtaining high dimensional accuracy at low cost. It is.

  FIG. 17 is a schematic view of the machining process. A photosensitive resin film is formed at least to a thickness equal to or greater than the thickness of the diaphragm to be formed on the surface of the conductive substrate. As the photosensitive resin, it is preferable to use a negative photosensitive resin SU-8 (manufactured by Kayaku Microchem Co., Ltd.) capable of forming a thick film by ordinary spin coating and forming a high aspect pattern. . As shown in FIG. 17A, the exposed photosensitive resin film is exposed through a photomask having a light transmitting portion corresponding to the opening shape of the through hole to be formed, and then subjected to heat treatment and development. In addition, a conductive substrate 30 having a surface formed with a photosensitive resin pattern corresponding to the through hole of the diaphragm can be obtained. By performing electrodeposition 32 on the substrate 30 to a predetermined film thickness, a state as shown in FIG. Thereafter, by separating the substrate from the electrodeposited metal film, a metal base material film having through holes can be obtained. Since the photosensitive resin SU-8 used here has a pattern shape having a vertical wall surface, the cross-sectional shape of the through-hole formed in the diaphragm is an equal rectangular cross-section at any film thickness position.

  FIG. 18 is a schematic view of another example of the machining process. A thin photosensitive resin layer 35 is formed at a thickness ti on a substrate surface 34 having at least a conductive surface. The photosensitive resin is not particularly specified, and any of a negative type and a positive type can be used as long as it has resistance to a plating solution at the time of electrodeposition. The thickness of the photosensitive resin layer 35 is not particularly specified, but is preferably in the range of 0.1 μm to 10 μm. If it is too thin, it will not function as an insulating film during electrodeposition performed in a later step, and if it is too thick, the pattern accuracy will deteriorate. Thereafter, a series of steps of exposure, heat treatment, and development are performed through a photomask that forms a target pattern on the photosensitive resin layer 35, and an unnecessary photosensitive resin layer is removed, thereby removing the photosensitive resin layer shown in FIG. A substrate 34 having the form as shown in A) is obtained. When electrodeposition is performed on the substrate surface until a desired diaphragm thickness T (T ≧ ti) is obtained, a state as shown in FIG. 18B is obtained. Thereafter, a metal base material diaphragm 36 having through holes 37 formed therein can be obtained by separating the substrate and the deposited metal film. In this method, electrodeposition is performed in excess of the thickness of the photosensitive resin. By doing so, the precipitate grows so as to protrude from the periphery to the photosensitive resin surface which is an insulator. By appropriately selecting the plating solution and conditions, it is possible to make the growth of electrodeposition equal in any direction. By performing electrodeposition under these conditions, the amount of protrusion onto the photosensitive resin is equal to the thickness obtained by subtracting the thickness of the photosensitive resin from the electrodeposition thickness, and the cross-sectional shape is centered on the photosensitive resin end. Is represented by a 1/4 arc. From this, the shape of the photosensitive resin produced on the substrate can be determined from the opening shape of the through hole to be formed, the film thickness of the photosensitive resin, and the film thickness of the diaphragm to be produced. More specifically, the photosensitive resin layer formed on the substrate when the opening shape on the surface in contact with the continuous layer of one through hole formed in the diaphragm is a rectangle of width ds and height dl. When the thickness of the film is ti and the thickness to be formed as a diaphragm is T, the amount of protrusion at the time of electrodeposition on the photosensitive resin is (T-ti). The amount obtained by expanding this amount to both sides of the width and height of the opening shape, that is, the width DS is a rectangle of DS = ds + 2 × (T−ti), and the height DL is a rectangle of DL = dl + 2 × (T−ti). The desired diaphragm can be obtained. The cross-sectional shape of the through hole is a shape that satisfies all of them.

20 (1) to 20 (5) are diagrams showing an example of a schematic process in the metal film forming method of the present invention. 21 is a plan view of each part shown in FIG. 20, FIG. 21 (1) is a plan view in the third step shown in FIG. 20 (3), and FIG. 21 (2) is shown in FIG. 20 (5). It is a top view in the 5th process shown.
As the first step shown in FIG. 20A, the conductive substrate 1 is prepared. For this, a conductive material such as a metal plate may be used, or a conductive film is deposited on the surface of an insulator or semiconductor such as glass or silicon, and a known composition such as vapor deposition, sputtering, or electroless plating. What was produced by the film | membrane means and the means which combined them may be used.
As a second step shown in FIG. 20B, the insulating layer 2 is formed on the entire surface of one side of the conductive substrate 1. This can be formed by forming a liquid material by spin coating or spray coating, or attaching a film-like material. The material is preferably a liquid resist, a dry film resist, or the like, but is not particularly limited as long as it is a substance that can be selectively removed in a later step and has low solubility in the plating solution.
As a third step shown in FIG. 20 (3), a part of the insulating layer 2 on the conductive substrate 1 is selectively removed to expose the conductive substrate 1. If the insulating layer 2 is a photoresist or a dry film resist, the exposed portion can be formed by developing after exposure through a photomask. Further, the removal process may be performed directly by laser irradiation.
The arrangement shape of the insulating layer openings 4 may be any shape as long as the insulating layer opening group 5 in an array that forms a polygon having three or more vertices is formed by a plurality of adjacent insulating layer openings 4. Specifically, as shown in FIG. 22 to FIG. 26 (1), the shape of the insulating layer opening 4 may be circular or rectangular. Of course, other shapes may be used. Furthermore, they do not have to be the same shape and size, and may be a combination of different ones.

As a fourth step shown in FIG. 20 (4), electroplating is performed using the substrate 1 obtained in the third step as a cathode. In the initial stage of plating, it is deposited only on the exposed part of the conductive substrate, but further plating is continued, and when the film thickness exceeds the thickness of the insulating layer 2, it starts to deposit on the insulating layer 2 and is proportional to the film thickness. Then, the precipitation area is expanded. The growth of plating in this state is isotropic with respect to all directions in contact with the plating solution. As plating continues further, adjacent precipitates come into contact with each other and become integrated.
When all the adjacent precipitates in the insulating layer opening group 5 are in contact with each other in this way, the insulating layer opening 4 surrounded by the plating film 3 is formed at the center thereof. If the plating is further continued from this state, the insulating layer opening 4 surrounded by the plating film 3 gradually becomes smaller and finally the entire surface is covered with the plating film 3.
By completing the plating at an arbitrary time from when the insulating layer opening 4 surrounded by the plating film 3 is formed until the entire surface is covered with the plating film 3, the insulating layer opening 4 having a desired size is obtained. Can do.
As the fifth step shown in FIG. 20 (5), the metal film 3 having the target insulating layer opening 4 is obtained by separating the plating film 3 and the conductive substrate 1. Specifically, when the insulating layer opening group 5 as shown in FIG. 22 to FIG. 26 (1) is formed, an opening shape as shown in FIG. 22 to FIG. 26 (2) is obtained.

22 (1) shows an insulating layer opening group 5 having circular insulating layer openings 4 of the same size, and FIG. 22 (2) is a substantially wedge formed by using the insulating layer 2 of FIG. An insulating layer opening 4 on the side of the plating film 3 having a mold (mesa shape) is shown. FIG. 23A shows a circular insulating layer opening 4 having a different diameter, and FIG. 23B shows a rectangular insulating film formed on the side of the plating film 3 formed by using the insulating layer 2 of FIG. A layer opening 4 is shown. 24, FIG. 25, and FIG. 26 also have the same relationship in each of the divided drawings (1) and (2).
A diaphragm having a through hole formed by the above-described method or other methods is a metal surface. When this surface is subjected to a hydrophilic treatment or a lipophilic treatment depending on the purpose of use, a better result can be obtained when it is used in an emulsifying apparatus. As a means, a method using vacuum film formation such as vapor deposition or sputtering is usually performed, and these may be used. However, the metal film of the present invention has fine and deep through-holes, and it is desirable that the inner surface of the through-holes be reliably treated in order to obtain better characteristics.
The diaphragm used in the emulsifying device of the present invention is a metal matrix, and its oxide generally exhibits good hydrophilicity. The thermal oxidation treatment that oxidizes a metal by heating it in an oxygen-containing atmosphere can easily treat the entire surface in contact with the oxygen-containing atmosphere at once. Further, since the oxide film formed thereby is dense and excellent in adhesion as compared with a method of depositing an oxide from the outside such as vacuum film formation, a more preferable result can be obtained. Furthermore, the thickness of the oxide film can be increased by forming the oxide film by another method. By increasing the thickness of the oxide film, hydrophilicity can be maintained for a long time even after a cleaning process, and the diaphragm can be used for a long time.
Moreover, it is desirable to process to the inner surface of a through-hole similarly to a hydrophilic process. A method in which the solvent is dried and removed after dip coating in a liquid in which a lipophilic substance is dissolved in a solvent is a desirable method because the treatment can be reliably performed up to the inner surface.

1 is a schematic view of a membrane emulsification apparatus in the present invention. The figure which shows the state which the dispersed phase adhered to the through-hole 22 vicinity of the diaphragm surface. The figure which shows a mode that the particle | grains of the state adjusted as a disperse phase are produced so that branching, confluence, etc. do not arise in the process which passes a through-hole when what disperse | distributes microparticles | fine-particles uniformly as a disperse phase. The figure which shows the example of the specific shape of a through-hole. The figure which shows the example of the specific shape of a through-hole. The figure which shows the example of the specific shape of a through-hole. The figure which shows the example of the specific shape of a through-hole. The figure which shows the shape which the width | variety does not change regarding the thickness direction in any cross section of a through-hole. FIG. 3 is a diagram in which the width of the dispersed phase is constant when the cross-sectional width is wider on the dispersed phase side than on the continuous phase side. FIG. 6 is a diagram in which when the cross-sectional width is wider on the dispersed phase side than on the continuous phase side, the width becomes narrower toward the continuous phase side. The figure which shows the process of particle | grain production | generation in three steps, and shows typically. The figure which shows the area | region which satisfy | fills two parameters | indexes with a part of through-hole diameter shape, and the shape. The figure which shows the area | region which satisfy | fills two parameters | indexes with a part of through-hole diameter shape, and the shape. The figure which shows the area | region which satisfy | fills two parameters | indexes with a part of through-hole diameter shape, and the shape. The figure which shows the area | region which satisfy | fills two parameters | indexes with a part of through-hole diameter shape, and the shape. The figure which shows the area | region which satisfy | fills two parameters | indexes with a part of through-hole diameter shape, and the shape. Schematic of a processing process. Schematic of the other example of a process process. Schematic of the other example of a process process. The figure which shows an example of the schematic process in the metal film formation method of this invention. The top view of each part shown in FIG. The figure which shows an example of insulating-layer opening. The figure which shows an example of insulating-layer opening. The figure which shows an example of insulating-layer opening. The figure which shows an example of insulating-layer opening. The figure which shows an example of insulating-layer opening. The process drawing of the emulsification method performed using a metal film. The figure which shows an example of the metal film opening by this invention with a continuous line, and shows the outline of the circle | round | yen which has an area equal to it with a dotted line.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conductive substrate 2 Insulating layer 3 Plating film 4 Insulating layer opening 5 Insulating layer opening group

Claims (21)

  A metal film comprising two or more through-holes having the same shape and independent from each other, wherein the entire exposed surface has a highly hydrophilic surface.   2. The metal film according to claim 1, wherein the through holes having the same shape are formed so as to face the same direction.   When the opening shapes on the front and back sides of the through hole are different, the smaller side, and when the opening shapes are equal, the shape is an index value F1 (F1 = (absolute maximum length) ^ 2 / area × π / 4) and index value indicating the shape. 3. The metal film according to claim 1, wherein a relationship of F1 ≧ 2 and F2 ≦ 0.8 is satisfied in F2 (F2 = 4π × area / (peripheral length) ^ 2).   In any cross section in the film thickness direction of the through-hole, the width on one side surface is W1 and the width on the other side surface is W2, and the relationship of W1 ≧ W2 is satisfied, and the width is anywhere in the thickness direction. 4. The metal film according to claim 1, wherein there is no portion larger than W <b> 1 and a portion smaller than W <b> 2.   5. The metal film according to claim 1, wherein the shortest distance from one surface of the through hole to the other surface is equal to the film thickness around the through hole.   In the cross-section in the film thickness direction of the through hole, when the width on one side surface is W1 and the width on the other side surface is W2, the relationship of W1 ≧ W2 is satisfied, and the position in the thickness direction on the surface where the width is W1 is When the thickness of the surface that becomes 0 and W2 is T, the arbitrary positions T1, T2, and T3 (0 <T1 <T2 <T3 <T) in the thickness direction and the widths WT1, WT2, and WT3 at the positions 6. The relationship according to claim 1, wherein the relationship is WT1 = WT2 = WT3 or (WT1-WT2) / (T2-T1) ≧ (WT2-WT3) / (T3-T2). Metal film.   A metal film comprising a metal base material and having two or more through-holes having the same shape independent from each other, and the entire exposed surface has a highly hydrophobic surface.   The metal film according to claim 7, wherein the through holes having the same shape are formed to face in the same direction.   When the opening shapes on the front and back sides of the through hole are different, the smaller side, and when the opening shapes are equal, the shape is an index value F1 (F1 = (absolute maximum length) ^ 2 / area × π / 4) and index value indicating the shape. 9. The metal film according to claim 7, wherein a relationship of F1 ≧ 2 and F2 ≦ 0.8 is satisfied in F2 (F2 = 4π × area / (peripheral length) ^ 2).   In any cross section in the film thickness direction of the through-hole, the width on one side surface is W1 and the width on the other side surface is W2, and the relationship of W1 ≧ W2 is satisfied, and the width is anywhere in the thickness direction. The metal film according to any one of claims 7 to 9, wherein there is no portion larger than W1 and a portion smaller than W2.   The metal film according to claim 7, wherein the shortest distance from one surface of the through hole to the other surface is equal to the film thickness around the through hole.   In the cross-section in the film thickness direction of the through hole, when the width on one side surface is W1 and the width on the other side surface is W2, the relationship of W1 ≧ W2 is satisfied, and the position in the thickness direction on the surface where the width is W1 is When the thickness of the surface that becomes 0 and W2 is T, the arbitrary positions T1, T2, and T3 (0 <T1 <T2 <T3 <T) in the thickness direction and the widths WT1, WT2, and WT3 at the positions 12. The relationship according to claim 7, wherein the relationship is WT1 = WT2 = WT3 or (WT1-WT2) / (T2-T1) ≧ (WT2-WT3) / (T3-T2). Metal film. A first step of preparing a conductive substrate at least on the surface; a second step of covering the surface of the conductive substrate with an insulating film; and partially removing the insulating film to expose the conductive surface A third step of forming, and a fourth step of forming an electroplating layer having a predetermined film thickness that does not cover the entire insulating layer with an insulating film or more with respect to the substrate on which the conductive surface is partially exposed, In the method for producing a metal film having a through-hole having an opening shape with different sizes on the front and back, the fifth step of separating the metal film obtained by the electroplating from the substrate,
Assuming that the thickness of the insulating film formed in the second step is ti and the thickness of the electroplating layer formed in the fourth step is T, as a result of being partially removed by the third step, A method of manufacturing a metal film, wherein the shape of the remaining insulating film is a shape spaced apart from the opening shape having a smaller area out of the openings to be formed in the metal film by a distance (T-ti). A first step of preparing a conductive substrate;
A second step of coating the surface of the conductive substrate with an insulating layer;
A third step of forming one or more insulating layer opening groups in a polygonal array having three or more vertices in the insulating layer, and exposing the conductive substrate in each insulating layer opening;
Electroplating is performed using the conductive substrate having the insulating layer opening formed as a cathode, so that precipitates from adjacent insulating layer openings in the insulating layer opening group are in contact with each other and a non-deposited portion remains in the center of the array. A fourth step of forming a plating film;
A fifth step of separating the conductive substrate and the plating film;
A method for producing a metal film, comprising:   15. The method for producing a metal film according to claim 13, wherein a step of covering the surface of the metal film with a hydrophilic film is performed as a sixth step after the fifth step.   The method for producing a metal film according to claim 15, wherein the step of covering with the hydrophilic film is performed by thermal oxidation.   The method for producing a metal film according to claim 16, wherein the step of covering with the hydrophilic film is thermally oxidized, and further the process of forming the hydrophilic film is performed.   15. The method for producing a metal film according to claim 13, wherein a step of covering the surface of the metal film with a hydrophobic film is performed as a sixth step after the fifth step.   The emulsification method characterized by extruding a dispersed phase in a continuous phase through the metal film as described in any one of Claims 1 thru | or 12.   Fine particles formed by the emulsification method according to claim 19. At least a continuous phase container, a dispersed phase container, a diaphragm having a large number of minute through holes separating the continuous phase container and the dispersed phase container, and a continuous phase for supplying the continuous phase container to the continuous phase container In a membrane emulsification apparatus comprising a continuous phase supply unit, a dispersed phase supply unit that supplies a dispersed phase to the dispersed phase storage unit, and a discharge unit for taking out the emulsion produced in the continuous phase storage unit,
The metal film according to any one of claims 1 to 12 is used as the diaphragm, and an absolute maximum length on one side surface of a through hole formed in the metal film is W1, and an absolute maximum length on the other surface is W2. The membrane emulsification apparatus is characterized in that the surface that becomes W1 in the relationship of W1 ≧ W2 is arranged on the side of the dispersed phase accommodating portion and the surface that becomes W2 is on the side of the continuous phase accommodating portion.

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