JP7552110B2 - Method for forming patterned film and patterned film - Google Patents

Description

The present invention relates to a patterned film.

Various methods have been reported for forming patterned films, including methods that use irradiation with active energy rays such as ultraviolet rays or electron beams, and methods that use self-organizing materials such as block copolymers.

JP 2009-260330 A JP 2016-197176 A

The present invention aims to provide a technology that enables the formation of patterned films in a simple manner.

According to a first aspect of the present invention, there is provided a method for forming a patterned film, the method including: forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with the active energy rays on a base having a plurality of recesses; irradiating the film with the active energy rays in a patterned manner to cure the first liquid in the areas irradiated with the active energy rays; removing at least a portion of the second liquid from the film by drying the film after irradiation with the active energy rays; and curing the uncured first liquid contained in the film from which at least a portion of the second liquid has been removed.

According to a second aspect of the present invention, there is provided a method for forming a patterned film, the method including: forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with active energy rays on a base having a plurality of recesses, such that the emulsion does not completely fill the plurality of recesses; irradiating the film with the active energy rays in a patterned manner to form a granular layer made of a cured product of the dispersed particles in the areas irradiated with the active energy rays; after irradiation with the active energy rays, drying the film to remove at least a portion of the second liquid from the film, and moving at least a portion of the uncured first liquid in the areas not irradiated with the active energy rays into gaps in the granular layer and into the plurality of recesses; and then curing the uncured first liquid.

According to a third aspect of the present invention, a method for producing a porous layer comprising the steps of: forming a first film on a substrate; the first film being made of a first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray; and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray; irradiating the first film with the first active energy ray to cure the first liquid; removing the second liquid from the first film after irradiation with the first active energy ray to obtain a porous layer made of a cured product of the first liquid; and forming on the porous layer second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray. and a second dispersion medium containing a fourth liquid that is not cured by irradiation with the second active energy ray; irradiating the second film with the second active energy ray in a patterned manner to cure the third liquid in the region irradiated with the second active energy ray; removing at least a portion of the fourth liquid from the second film by drying the second film after irradiation with the second active energy ray; and curing the uncured third liquid contained in the second film from which at least a portion of the fourth liquid has been removed.

According to a fourth aspect of the present invention, there is provided a method for producing a porous layer comprising a first emulsion on a substrate, the first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray; irradiating the first film with the first active energy ray to form a porous layer made of a cured product of the first dispersed particles; drying the porous layer to remove the second liquid from the porous layer; and forming, on the porous layer, second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray, and a first dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray. and forming a second film made of a second emulsion containing the second dispersed particles; irradiating the second film with the second active energy ray in a pattern to form a granular layer made of a cured product of the second dispersed particles in the region irradiated with the second active energy ray; after the irradiation with the second active energy ray, drying the second film to remove at least a portion of the fourth liquid from the second film, thereby moving at least a portion of the uncured third liquid in the region not irradiated with the second active energy ray into the granular layer and the porous layer; and then curing the uncured third liquid.

According to a fifth aspect of the present invention, there is provided a patterned film formed by a method according to any one of the first to fourth aspects.

According to a sixth aspect of the present invention, there is provided a structure comprising a base having a plurality of recesses, a granular layer partially covering the base, and a cured product at least partially filling the gaps between the plurality of recesses and the granular layer.

The present invention provides a technology that enables the formation of patterned films in a simple manner.

3A to 3C are cross-sectional views each showing a schematic process of forming a first film made of a first emulsion in the method of forming a pattern film according to an embodiment of the present invention. 3 is a cross-sectional view that illustrates a first active energy ray irradiation step in the method for forming a pattern film according to an embodiment of the present invention. FIG. FIG. 4 is a cross-sectional view illustrating a structure obtained after a second liquid removing step in the method for forming a pattern film according to an embodiment of the present invention. 4A to 4C are cross-sectional views each showing a schematic process of forming a second film made of a second emulsion in the method of forming a pattern film according to an embodiment of the present invention. FIG. 4 is a cross-sectional view illustrating a second active energy ray irradiation step in the method for forming a pattern film according to an embodiment of the present invention. 6A to 6C are cross-sectional views each showing a schematic diagram of a removing step of a fourth liquid in the method for forming a pattern film according to an embodiment of the present invention. FIG. 11 is a cross-sectional view illustrating a structure obtained after a fourth liquid removing step in the method for forming a pattern film according to the embodiment of the present invention. 5A to 5C are cross-sectional views each showing a schematic process of curing an uncured third liquid in the method for forming a pattern film according to an embodiment of the present invention. 9 is an optical microscope photograph of a film immediately after being irradiated with active energy rays in a patterned manner in a method for forming a patterned film similar to the method shown in FIGS. 1 to 8 except that the porous layer is omitted, with a black layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film taken 20 minutes after completion of patternwise irradiation with active energy rays, with a black layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film 40 minutes after completion of patternwise irradiation with active energy rays was taken with a black layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film 50 minutes after completion of patternwise irradiation with active energy rays was taken with a black layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film taken 60 minutes after completion of patternwise irradiation with active energy rays, with a black layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film taken 70 minutes after completion of patternwise irradiation with active energy rays, with a black layer placed behind the sample. Optical microscope photograph of the membrane of FIG. 14 with a white layer placed behind the sample. 1 to 8 except that the porous layer is omitted. An optical microscope photograph of the film taken 120 minutes after completion of patternwise irradiation with active energy rays, with a black layer placed behind the sample. Optical microscope photograph of the membrane of FIG. 16 with a white layer placed behind the sample. An optical microscope photograph taken after gold was sputtered onto the film of FIG. 16. Graph showing particle size distribution of emulsion. 4 is a graph showing the relationship between the penetration depth of an oligomer into a porous layer and the elapsed time, calculated on the assumption that the pores in the porous layer are capillaries. 1 is a graph showing the relationship between the permeation volume of an oligomer into a porous layer and the elapsed time, calculated on the assumption that the pores in the porous layer are capillaries. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 49.8 μm and 28.1 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are each 75 μL. The obtained film was illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 49.8 μm and 28.1 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are 75 μL and 82 μL, respectively. The obtained films were illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 49.8 μm and 28.1 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are 75 μL and 90 μL, respectively. The obtained films were illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 49.8 μm and 28.1 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are 75 μL and 100 μL, respectively. The obtained films were illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 49.8 μm and 28.1 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are 75 μL and 112 μL, respectively. The obtained films were illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 28.1 μm and 49.8 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are each 75 μL. The obtained film was illuminated with oblique incident light and photographed. 1 to 8, the average particle size of the first dispersed particles and the average particle size of the second dispersed particles are 28.1 μm and 49.8 μm, respectively, and the amount of the first emulsion and the amount of the second emulsion are 75 μL and 112 μL, respectively. The obtained films were illuminated with oblique incident light and photographed. 28 is a graph showing cross-sectional profiles obtained by three-dimensional shape measurements on the films of FIGS. 22 and 27 . 29 is a graph showing cross-sectional profiles obtained by three-dimensional shape measurements on the membranes of FIGS. 26 and 28 .

Embodiments of the present invention will be described in detail below with reference to the drawings. Note that components that perform the same or similar functions are given the same reference numbers throughout the drawings, and duplicate descriptions will be omitted.

The method for forming a patterned film will be explained below in the order of steps. To facilitate understanding of each step, an example of the state of the film at each step is shown in Figures 1 to 8, and these figures will be referred to in the following explanation.

<Preparation of First Emulsion>
First, a first emulsion is prepared, which contains first dispersed particles containing a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium containing a second liquid that is not cured by irradiation with the first active energy ray.

The first emulsion may be an oil-in-water (O/W) emulsion or a water-in-oil (W/O) emulsion.

The first dispersed particles contain a first liquid that is cured by irradiation with a first active energy ray. Examples of the first active energy ray include ultraviolet rays, electron beams, and X-rays. For example, an acrylic monomer or oligomer, a methacrylic monomer or oligomer, an epoxy monomer or oligomer, or a mixture containing one or more of them can be used as the first liquid. It is preferable to use an acrylic monomer or oligomer, or a methacrylic monomer or oligomer as the first liquid because of advantages such as a wide range of options and a large degree of freedom in adjusting physical properties. For example, trimethylolpropane triacrylate can be used as the first liquid. The ratio of the monomer and oligomer in the first liquid is, for example, 30 to 100 mass %.

The first liquid that hardens when irradiated with the first active energy rays has more types of lipophilic liquids than hydrophilic liquids. Therefore, O/W emulsions offer greater freedom in material selection than W/O emulsions.

The first dispersion medium contains a second liquid that does not harden when irradiated with the first active energy ray. When the first liquid is lipophilic, the second liquid can be a hydrophilic liquid, such as water, a lower alcohol such as methanol or ethanol, or a mixture thereof. On the other hand, when the first liquid is hydrophilic, the second liquid can be a lipophilic liquid, such as an isoparaffinic solvent or mineral spirits.

According to one example, the average particle size of the first dispersed particles is in the range of 5 μm to 0.5 mm. Here, the "average particle size" is the weight average diameter obtained by particle size distribution measurement according to a laser diffraction/scattering method. When the first dispersed particles have the above size, the uncured third liquid described below can be efficiently permeated into the gaps between the first cured particles formed by curing the first dispersed particles in a later process.

The average particle size of the first dispersed particles may be equal to or different from the average particle size of the second dispersed particles described below. In the latter case, the average particle size of the first dispersed particles may be smaller than the average particle size of the second dispersed particles, but is preferably larger than the average particle size of the second dispersed particles. When the average particle size of the first dispersed particles is larger than the average particle size of the second dispersed particles, a pattern film with better shape accuracy can be formed. The ratio D1/D2 of the average particle size D1 of the first dispersed particles to the average particle size D2 of the second dispersed particles is preferably in the range of 0.02 to 20, and more preferably in the range of 0.1 to 10.

The proportion of the first dispersed particles in the first emulsion is preferably 25% by mass or more. When the first dispersed particles occupy the above proportion in the first emulsion, the temperature of the area irradiated with the first active energy ray can be increased by effectively utilizing the heat of polymerization to destabilize the dispersion state of the first dispersed particles containing the first liquid and form a first aggregate layer at the same time. The upper limit of the proportion of the first dispersed particles in the first emulsion is not particularly limited as long as it is within a range in which phase inversion of the first emulsion does not occur. According to one example, this proportion is 70% by mass or less.

The first liquid may further contain a photopolymerization initiator. As the photopolymerization initiator, a known photopolymerization initiator, for example, an alkylphenone-based photopolymerization initiator, can be used. As an alkylphenone-based photopolymerization initiator, for example, 1-hydroxycyclohexyl phenyl ketone can be mentioned. The first liquid may contain the photopolymerization initiator in an amount of, for example, 0.1 to 10 parts by mass per 100 parts by mass of the total amount of the monomer and oligomer.

When the first emulsion is, for example, an O/W type, the first dispersed particles may contain a hydrophobe in addition to the first liquid. Examples of hydrophobes include higher alcohols with low solubility in water, such as cetyl alcohol, hexadecane, polymerizable monomers with relatively large molecular weights of the hydrocarbon chain, such as lauryl methacrylate and stearyl methacrylate, hydrophobic dyes, and polymers, such as polymethyl methacrylate and polystyrene. The hydrophobe serves to stabilize the first emulsion. The hydrophobe can be contained in an amount of, for example, 0.1 to 10 parts by mass per 100 parts by mass of the first liquid.

The first dispersion medium may further contain a surfactant. For example, a surfactant commercially available for use in emulsion polymerization may be used as the surfactant. For example, a sulfosuccinate type surfactant such as sodium dioctyl sulfosuccinate may be used as the surfactant. The first emulsion may contain the surfactant in an amount of, for example, 0.1 to 5.0% by mass based on the total mass of the first emulsion.

When the first emulsion is an O/W type emulsion, the first dispersion medium generally contains a surfactant in order to ensure emulsification and stability of the first dispersed particles. In addition, this O/W type emulsion may contain a water-soluble polymer or cellulose nanofiber in the first dispersion medium in order to improve the long-term storage stability of the first emulsion. Furthermore, if necessary, this O/W type emulsion may contain a viscosity modifier or an antifoaming agent in the first dispersion medium.

On the other hand, when the first emulsion is a W/O type emulsion, in order to prepare a stable emulsion, the first dispersion medium may contain a nonionic surfactant or a polymeric dispersion stabilizer having an appropriate hydrophilic-lipophilic balance (HLB) value. If necessary, this W/O type emulsion may also contain an ionic surfactant in the first dispersion medium.

The first emulsion can be prepared using known emulsification and dispersion techniques, such as a paint shaker, ultrasonic homogenizer, colloid mill, homogenizer, and membrane emulsification method.

<Formation of First Film>
Next, a first film made of the first emulsion is formed on a substrate. Hereinafter, the "first film made of the first emulsion" is also referred to as a first liquid film. Specifically, the first liquid film can be formed on the substrate by applying the first emulsion onto the substrate. Any substrate can be used as the substrate, and for example, a film or a sheet can be used.

The coating method is not particularly limited, but an appropriate coating method, such as die coating, comma coating, or curtain coating, can be selected depending on the thickness of the first liquid film. The thickness of the first liquid film can be, for example, 10 to 3000 μm. In addition, when applying a small amount of the first emulsion to form a first liquid film with a small area, a dispenser or the like can be used as necessary.

Figure 1 shows a schematic diagram of an example of a state in which a first film made of a first emulsion is formed on a substrate. In Figure 1, a first film 2a1 made of a first emulsion composed of first dispersed particles 21a1 and a first dispersion medium 22a1 is formed on a substrate 1.

<Irradiation of first active energy ray>
Next, the formed first film is irradiated with a first active energy ray. As the first active energy ray, as described above, for example, ultraviolet light, an electron beam, or an X-ray can be mentioned.

The first active energy ray may be irradiated to the entire first film, or may be irradiated to the first film in a pattern. Pattern irradiation can be performed, for example, by selectively irradiating the first active energy ray through a mask or by selectively irradiating the first film with laser light. Here, as an example, the first active energy ray is irradiated to the entire first film.

By irradiating the first active energy ray, the first liquid contained in the first dispersed particles is polymerized and hardened in the area of the first film irradiated with the first active energy ray (hereinafter also referred to as the first irradiated area). This allows the formation of a porous layer made of the hardened product of the first dispersed particles.

Figure 2 shows an example of a porous layer formed of a hardened product of the first dispersed particles by ultraviolet irradiation. As shown in Figure 2, in the area irradiated with ultraviolet rays, the first liquid contained in the first dispersed particles 21a1 is hardened by polymerization, and the first dispersed particles 21a1 become hardened products 21b1. These hardened products 21b1 are aggregated and stacked, and as a result, a porous layer 2b1 made of the hardened products 21b1 is formed. On the other hand, since the second liquid contained in the first dispersion medium 22a1 does not harden, the first dispersion medium 22a1 exists in the porous layer 2b1, specifically, in the gaps between the hardened products 21b1. On the other hand, in Figure 2, in the area not irradiated with ultraviolet rays, the first liquid contained in the first dispersed particles 21a1 remains unhardened.

The aggregation of the cured material 21b1 in the first irradiation region may be promoted by incorporating a crosslinking agent in the first dispersion medium in advance. This makes it easier for crosslinks to form between the particles when irradiated with the first active energy ray, thereby promoting the aggregation of the particles.

<Removal of second liquid>
After the irradiation of the first active energy ray, the second liquid is removed from the porous layer. The second liquid can be removed, for example, by drying the porous layer. The second liquid can be removed by leaving the porous layer at room temperature, but is preferably removed by heating and drying the porous layer. The heating and drying can be performed, for example, by heating the porous layer at a temperature in the range of 40 to 100° C. for 0.1 to 1 hour.

Figure 3 shows a schematic diagram of an example of a porous layer from which the second liquid has been removed. The porous layer 2b1 shown in Figure 3 is made of an aggregate of hardened material 21b1. The porous layer 2b1 has gaps between the hardened material 21b1.

<Preparation of Second Emulsion>
While the porous layer is formed as described above, a second emulsion is prepared, the second emulsion including second dispersion particles including a third liquid that is cured by irradiation with a second active energy ray, and a second dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray. The preparation of the second emulsion may be performed in parallel with the formation of the porous layer, may be performed prior to the formation of the porous layer, or may be performed after the formation of the porous layer.

The second emulsion may be an oil-in-water (O/W) emulsion or a water-in-oil (W/O) emulsion.

The second dispersed particles contain a third liquid that is cured by irradiation with a second active energy ray.
Examples of the second active energy ray include ultraviolet light, electron beams, and X-rays. The second active energy ray may be the same as or different from the first active energy ray.

As the third liquid, for example, an acrylic monomer or oligomer, a methacrylic monomer or oligomer, an epoxy monomer or oligomer, or a mixture containing one or more of them can be used. As the third liquid, it is preferable to use an acrylic monomer or oligomer, or a methacrylic monomer or oligomer, because of advantages such as a wide range of options and a large degree of freedom in adjusting physical properties. As the third liquid, for example, trimethylolpropane triacrylate can be used. The ratio of the monomer and oligomer in the third liquid is, for example, 30 to 100 mass %. The third liquid may be the same as the first liquid, or may be different.

The third liquid that hardens when irradiated with the second active energy rays has more types of lipophilic liquids than hydrophilic liquids. Therefore, O/W type emulsions offer greater freedom in material selection than W/O type emulsions.

The second dispersion medium includes a fourth liquid that does not harden when irradiated with the second active energy ray. When the third liquid is lipophilic, the fourth liquid can be a hydrophilic liquid, such as water, a lower alcohol such as methanol or ethanol, or a mixture thereof. On the other hand, when the third liquid is hydrophilic, the fourth liquid can be a lipophilic liquid, such as an isoparaffin solvent or mineral spirits.

The second dispersed particles preferably have an average particle size of 0.5 μm to 0.5 mm, depending on the size of the pattern to be formed. If the second dispersed particles have the above size, the uncured third liquid can be efficiently permeated into the gaps between the particles in a later process.

The proportion of the second dispersed particles in the second emulsion is preferably 25% by mass or more. When the second dispersed particles occupy the above proportion in the second emulsion, the temperature of the area irradiated with the second active energy rays can be increased by effectively utilizing the heat of polymerization to destabilize the dispersion state of the second dispersed particles containing the third liquid and form an aggregate layer at the same time. The upper limit of the proportion of the second dispersed particles in the second emulsion is not particularly limited as long as it is within a range in which phase inversion of the second emulsion does not occur. According to one example, this proportion is 70% by mass or less.

The third liquid may further contain a photopolymerization initiator. As the photopolymerization initiator, a known photopolymerization initiator, for example, an alkylphenone-based photopolymerization initiator, can be used. As an alkylphenone-based photopolymerization initiator, for example, 1-hydroxycyclohexyl phenyl ketone can be mentioned. The third liquid may contain the photopolymerization initiator in an amount of, for example, 0.1 to 10 parts by mass per 100 parts by mass of the total amount of the monomer and oligomer.

When the second emulsion is, for example, an O/W type, the second dispersed particles may contain a hydrophobe in addition to the third liquid. Examples of hydrophobes include higher alcohols with low solubility in water, such as cetyl alcohol, hexadecane, polymerizable monomers with relatively large molecular weights of the hydrocarbon chain, such as lauryl methacrylate and stearyl methacrylate, hydrophobic dyes, and polymers, such as polymethyl methacrylate and polystyrene. The hydrophobe serves to stabilize the second emulsion. The hydrophobe can be contained in an amount of, for example, 0.1 to 10 parts by mass per 100 parts by mass of the first liquid.

The second dispersion medium may further contain a surfactant. For example, a commercially available surfactant for use in emulsion polymerization may be used as the surfactant. For example, a sulfosuccinate type surfactant such as dioctyl sodium sulfosuccinate may be used as the surfactant. The second emulsion may contain the surfactant in an amount of, for example, 0.1 to 5.0% by mass based on the total mass of the second emulsion.

When the second emulsion is an O/W type emulsion, the second dispersion medium generally contains a surfactant in order to ensure emulsification and stability of the second dispersed particles. In addition, this O/W type emulsion may contain a water-soluble polymer or cellulose nanofiber in the second dispersion medium in order to improve the long-term storage stability of the second emulsion. Furthermore, if necessary, this O/W type emulsion may contain a viscosity adjuster or an antifoaming agent in the second dispersion medium.

On the other hand, when the second emulsion is a W/O type emulsion, in order to prepare a stable emulsion, the second dispersion medium may contain a nonionic surfactant or a polymeric dispersion stabilizer having an appropriate hydrophilic-lipophilic balance (HLB) value. If necessary, this W/O type emulsion may also contain an ionic surfactant in the second dispersion medium.

The second emulsion can be prepared using known emulsification and dispersion techniques, such as a paint shaker, ultrasonic homogenizer, colloid mill, homogenizer, and membrane emulsification method.

<Formation of second film>
Next, a second film made of the second emulsion is formed on the porous layer. Hereinafter, the "second film made of the second emulsion" is also referred to as a second liquid film. Specifically, the second liquid film can be formed on the porous layer by applying the second emulsion onto the porous layer.

The coating method is not particularly limited, but an appropriate coating method, such as die coating, comma coating, or curtain coating, can be selected depending on the thickness of the second liquid film. The thickness of the second liquid film can be, for example, 10 to 3000 μm. In addition, when applying a small amount of the second emulsion to form a second liquid film with a small area, a dispenser or the like can be used as necessary.

If the hardened product of the first dispersed particles is hydrophilic, the third liquid is hydrophilic, and the fourth liquid is hydrophobic, the second emulsion does not penetrate the porous layer at this stage. If the hardened product of the first dispersed particles is hydrophobic, the third liquid is hydrophobic, and the fourth liquid is hydrophilic, the second emulsion does not penetrate the porous layer at this stage. If the hardened product of the first dispersed particles is hydrophilic, the third liquid is hydrophobic, and the fourth liquid is hydrophilic, the fourth liquid may partially penetrate the porous layer at this stage, but the third liquid does not penetrate the porous layer, and therefore the second emulsion hardly penetrates the porous layer. If the hardened product of the first dispersed particles is hydrophobic, the third liquid is hydrophilic, and the fourth liquid is hydrophobic, the fourth liquid may partially penetrate the porous layer at this stage, but the third liquid does not penetrate the porous layer, and therefore the second emulsion hardly penetrates the porous layer.

Figure 4 shows a schematic diagram of an example of a state in which a second film made of a second emulsion is formed on a porous layer. In Figure 4, a second film 2a2 made of a second emulsion composed of second dispersion particles 21a2 and a second dispersion medium 22a2 is formed on the porous layer 2b1.

<Irradiation with second active energy ray>
Next, the formed second film is irradiated with a second active energy ray in a pattern. As the second active energy ray, as described above, for example, ultraviolet rays, electron beams, X-rays, etc. can be mentioned. The pattern irradiation can be carried out, for example, by selectively irradiating the second active energy ray through a mask or the like, or by selectively irradiating the laser beam.

By irradiating the second active energy rays in a pattern, the third liquid contained in the second dispersed particles is polymerized and cured in the area irradiated with the second active energy rays (hereinafter also referred to as the second irradiation area). This allows the formation of a granular layer made of the cured product of the second dispersed particles.

Figure 5 shows an example of a state in which a granular layer made of the hardened product of the second dispersed particles is formed in the area irradiated with ultraviolet light by patterned irradiation of ultraviolet light. As shown in Figure 5, in the area irradiated with ultraviolet light, the third liquid contained in the second dispersed particles 21a2 is hardened by polymerization, and the second dispersed particles 21a2 become the hardened product 21b2. These hardened products 21b2 are aggregated and stacked, and as a result, a granular layer 2b2 made of the hardened product 21b2 is formed. In the area irradiated with ultraviolet light, the fourth liquid contained in the second dispersion medium 22a2 does not harden, so the second dispersion medium 22a2 exists in the granular layer 2b2, specifically, in the gaps between the hardened products 21b2. On the other hand, in Figure 5, in the area not irradiated with ultraviolet light (hereinafter also referred to as the non-irradiated area), the third liquid contained in the second dispersed particles 21a2 remains unhardened.

Regarding the aggregation mechanism of the cured material 21b2 in the second irradiation area, the inventor believes that the reason is as follows.

By irradiation with the second active energy rays, the second dispersed particles 21a2 generate heat due to polymerization, and the temperature of the second irradiated area rises. This temperature rise causes the surfactant that has been adsorbed to the surface of the second dispersed particles 21a2 and stabilized the dispersion of the second dispersed particles 21a2 to be desorbed. This reduces the surface potential of the second dispersed particles 21a2 where polymerization has progressed. As a result, the dispersion of the second dispersed particles 21a2 or their cured product 21b2 becomes unstable, and particle aggregation is promoted. In addition, as the particles aggregate and come into contact with each other, polymerization crosslinking may occur between the particles.

This aggregation is completed before the surfactant that has been released due to the temperature rise caused by the heat of polymerization is re-adsorbed onto the particles. This allows the aggregated particles to maintain their aggregated state without being re-dispersed.

The aggregation of the cured material 21b2 in the second irradiation region may be promoted by incorporating a crosslinking agent into the dispersion medium in advance. This makes it easier for crosslinks to form between the particles when irradiated with active energy rays, thereby promoting the aggregation of the particles.

<Removal of the fourth liquid>
After the irradiation of the second active energy ray, at least a part of the fourth liquid is removed from the second film. In this step, at least a part of the fourth liquid may be removed, but the entire fourth liquid may be removed. The removal of the fourth liquid may be performed, for example, by drying the second film. The drying is preferably performed until the amount of the fourth liquid is 30% by mass or less of the amount of the fourth liquid immediately after the formation of the second liquid film, and more preferably until the amount is 5% by mass or less. The removal of the fourth liquid may be performed by leaving the second film at room temperature, but is preferably performed by heating and drying the second film. The heating and drying may be performed, for example, by heating the second film at a temperature in the range of 40 to 100° C. for 0.1 to 1 hour.

In this process, by removing the fourth liquid, at least a portion of the uncured third liquid is moved from the non-irradiated region to the granular layer consisting of the cured product of the second dispersed particles. The movement of the uncured third liquid from the non-irradiated region to the granular layer may be performed so that all of it moves to the granular layer, or so that only a portion of it moves to the granular layer. When only a portion of the uncured third liquid moves from the irradiated region to the granular layer, the other portion of the uncured third liquid can be absorbed by the porous layer.

This migration proceeds particularly quickly when the hardened product of the first dispersed particles is hydrophilic and the third liquid is hydrophilic, or when the hardened product of the first dispersed particles is hydrophobic and the third liquid is hydrophobic. However, the above migration can occur even when the hardened product of the first dispersed particles is hydrophilic and the third liquid is hydrophobic, or when the hardened product of the first dispersed particles is hydrophobic and the third liquid is hydrophilic.

In this method, it is not necessary to carry out a development step after irradiation with the second active energy rays, i.e., removal of the uncured third liquid using a developer.

Figures 6 and 7 show schematic examples of changes in the state of the second film caused by the removal of the second liquid. Figure 6 shows schematic examples of a state in which coalescence of the second dispersed particles occurs in the non-irradiated region by starting the removal of the fourth liquid from the second film. Figure 7 shows schematic examples of a state in which the coalescence of the second dispersed particles has penetrated into a porous layer made of the hardened product of the first dispersed particles and a granular layer made of the hardened product of the second dispersed particles.

When a part of the fourth liquid contained in the second dispersion medium 22a2 is removed from the second film 2a2, as shown in FIG. 6, the fourth liquid that filled the gaps between the particles in the granular layer 2b2 is reduced in the second irradiation area, and the fourth liquid is reduced in the non-irradiation area, and the second dispersion particles 21a2 are united. Then, as shown in FIG. 7, the united 21a2' formed by the uniting of the second dispersion particles 21a2, that is, the uncured third liquid, is partially permeated into the gaps in the granular layer 2b2 and diffused into the granular layer 2b2, and the other part permeates into the gaps in the porous layer 2b1 and diffuses into the porous layer 2b1. This permeation and diffusion are thought to proceed by capillary force. When the removal of the fourth liquid is completed, the movement of the uncured third liquid from the non-irradiation area to the granular layer 2b2 and the porous layer 2b1 is completed. As a result, for example, a structure shown in FIG. 7 is obtained. When the fourth liquid is completely removed from the second film, the only liquid remaining in the film is, for example, the liquid that constitutes the combined bodies 21a2' of the second dispersion particles 21a2.

<Establishing the pattern>
Finally, the uncured third liquid contained in the film from which the fourth liquid has been removed is cured. The uncured third liquid can be cured, for example, by irradiating the entire film with the second active energy ray. This forms a patterned film.

Figure 8 shows a schematic example of the state in which the uncured third liquid has been cured by irradiating the entire surface with ultraviolet light. As shown in Figure 8, when the entire film is irradiated with ultraviolet light, the uncured third liquid is cured by polymerization. As a result, a polymerized phase 21b2' is formed. Furthermore, in the cured material 21b2 that constitutes the granular layer 2b2, further polymerization proceeds due to ultraviolet light irradiation. And, in the cured material 21b1 that constitutes the porous layer 2b1, further polymerization proceeds due to ultraviolet light irradiation.

This results in a structure having a porous layer 2b1, which is a base having a plurality of recesses, a granular layer 2b2 that partially covers the base, and a polymerized phase 21b2', which is a hardened product that at least partially fills the recesses provided by the porous layer 2b1 and the gaps in the granular layer 2b2. In this structure, the porous layer 2b1 and a part of the polymerized phase 21b2' constitute the first layer 2B1, and the granular layer 2b2 and another part of the polymerized phase 21b2' constitute the second layer 2B2, which is a pattern film that partially covers the first layer 2B1.

As described above, the uncured third liquid can be cured after all of the uncured third liquid present in the non-irradiated region has moved from this region to the granular layer and the porous layer. Alternatively, the uncured third liquid can be cured when only a portion of the uncured third liquid present in the non-irradiated region has moved from this region to the granular layer and the porous layer. For example, the second active energy ray may be irradiated to the entire film before the fourth liquid is completely removed from the film (i.e., at a stage in the middle of the third liquid in the non-irradiated region penetrating and diffusing therein). In this way, a pattern film having a thickness in the non-irradiated region and a second irradiated region thicker than the non-irradiated region can be obtained.

＜Effects＞
In the above method, the second emulsion film formed on the base having a plurality of recesses is irradiated with the second active energy ray in a pattern, and then the fourth liquid is simply removed, so that the pattern can be formed spontaneously (in a self-organizing manner). In the above method, it is not necessary to provide a guide pattern on the base material in advance, and no development process is required. Therefore, the above method is a simple method.

Furthermore, while conventional techniques could achieve pattern sizes of, for example, a line width of several nm to several hundred μm and a height difference of several nm to several hundred μm, the above method can achieve a wide range of pattern sizes. For example, the above method can form a pattern film with a large line width or height difference, for example, a line width on the order of microns to millimeters and a height difference on the order of microns to millimeters. As an example, the above method can form a pattern film with a line width in the range of 10 μm to 5 mm and a height difference in the range of 10 μm to 2 mm.

Furthermore, the above method has excellent control over the shape and size of the pattern, making it possible to form pattern films of various shapes and sizes. In particular, in this method, the film of the second emulsion is formed on a substrate having multiple recesses rather than on a flat substrate, so that a pattern film with excellent shape accuracy can be formed, as described below.

When forming a high-density pattern, for example, a line-and-space pattern with a large ratio of line width to space width, the amount of the third liquid that constitutes the combined body 21a2' resulting from the removal of the fourth liquid described with reference to Figures 6 and 7 is small. Therefore, even if the base is flat, i.e., the base cannot absorb the third liquid, the granular layer 2b2 can absorb almost the entire amount of the third liquid in the non-irradiated area. Therefore, a pattern film with excellent shape accuracy can be formed.

In contrast, when forming a low-density pattern, for example, when forming a line-and-space pattern with a small ratio of line width to space width, the amount of the third liquid that constitutes the combined liquid 21a2' resulting from the removal of the fourth liquid described with reference to Figures 6 and 7 is large. Therefore, when the base is flat, i.e., when the base cannot absorb the third liquid, the granular layer 2b2 can only absorb a portion of the third liquid in the non-irradiated area, and the remaining third liquid may remain in the non-irradiated area. Therefore, in this case, it may not be possible to form a pattern film with excellent shape accuracy.

In the method described with reference to Figures 1 to 8, the porous layer 2b1 is formed as a base having a plurality of recesses. Therefore, even if the granular layer 2b2 can only absorb a portion of the third liquid in the non-irradiated area, the excess third liquid can be absorbed by the porous layer 2b1. Therefore, this method can form a pattern film with excellent shape accuracy.

<Modification>
In the method described with reference to Figures 1 to 8, a porous layer made of a cured product of the second dispersed particles is formed to provide a base having a plurality of recesses. The porous layer may be formed by other methods instead of the method using the first emulsion. Also, if at least the surface region of the substrate is porous, the porous layer does not need to be formed. Also, the base having a plurality of recesses may be a base having a surface provided with a plurality of grooves.

In either case, the width or diameter of each recess on the substrate surface is preferably within the range of 5 μm to 300 μm, and more preferably within the range of 10 μm to 200 μm. Also, the average center-to-center distance between adjacent recesses on the substrate surface is preferably within the range of 10 μm to 500 μm, and more preferably within the range of 20 μm to 350 μm.

[1] Test 1
In this test, a pattern film was formed in the same manner as described with reference to FIGS. 1 to 8, except that no porous layer was formed, and the shape accuracy was examined.

<Preparation of emulsion>
An O/W type emulsion was prepared as the second emulsion using the following materials.
Trimethylolpropane triacrylate: Light Acrylate TMP-A (Kyoeisha Chemical Co., Ltd.)
Photopolymerization initiator: Lunacure 200 (DKSH Japan Co., Ltd.)
Surfactant: Sanmorin OT-70 (86.7% aqueous solution) (Sanyo Chemical Industries, Ltd.)
Fourth liquid: Water (distilled water)
In a brown vial with a capacity of 50 mL, 0.375 g of a photopolymerization initiator (Lunacure 200), 0.259 g of a surfactant (Sunmorin OT-70), and 7.5 g of trimethylolpropane triacrylate (Light Acrylate TMP-A) were charged in this order, and a rotary mixing process was performed on a ball mill roll. Next, 9 g of distilled water was added to obtain a mixed solution that is a precursor of the second emulsion. After that, this mixed solution was subjected to an emulsification dispersion process using a homogenizer. Next, the vial was rotary mixed for 30 minutes. In this manner, the second emulsion was obtained.

<Formation of liquid film>
Five layers of 20 mm wide, 80 μm thick masking tape (manufactured by 3M) were attached to the surface of a microscope slide along its long side, and the center of the tape was cut out into a rectangular shape to produce a cell with a liquid reservoir of 400 μm deep and 10 mm × 30 mm area (hereinafter referred to as a liquid reservoir cell).
Next, 112 μL of the emulsion was collected using a micropipette and spread and filled into a liquid-reservoir cell to prepare a membrane (i.e., a second liquid membrane) made of the second emulsion and having a thickness of about 375 μm, calculated taking into account the specific gravity.

<Irradiation with energy rays>
Next, a copper mask having a thickness of 0.25 mm and a slit-shaped opening having a width of 2 mm was placed on the second liquid film via an aluminum spacer having a thickness of 1 mm so as not to come into contact with the liquid surface. Next, a UV parallel light exposure machine (UVC-2502S manufactured by SAN-EI ELECTRONIC) was used to irradiate the mask with ultraviolet light having an illuminance of 4.6 mW/ ^cm2 for 8 seconds, thereby exposing the liquid film to an integrated light quantity of 36.8 mJ/ ^cm2 . As a result, the third liquid was polymerized in the area irradiated with the ultraviolet light, forming a granular layer made of a cured product of the second dispersed particles.

<Drying the film>
Next, the film after the ultraviolet exposure was naturally dried (23°C, 57% RH) for 45 minutes at room temperature. Photographs showing the state of the film during the drying process are shown in Figures 9 to 18. As shown in Figure 9, an aggregated pattern was formed in the irradiated area immediately after exposure. As shown in Figures 9 to 18, as the drying progressed, the uncured emulsion droplets in the non-irradiated area were united, and a part of the third liquid constituting them was penetrated and absorbed into the granular layer (aggregated layer of cured emulsion droplets) in the irradiated area. However, the remaining third liquid in the non-irradiated area was not absorbed by the granular layer and formed an amorphous layer adjacent to the granular layer. Thus, in this test, a patterned film having a shape corresponding to the opening of the copper mask was not obtained.

[2] Test 2
In this test, a pattern film was formed by the same method as that described with reference to Figures 1 to 8. Then, the influence of the average particle diameters of the first and second dispersed particles on the shape accuracy of the pattern film was examined.

<Preparation of emulsion>
Emulsions E1 and E2 were prepared in the same manner as in Test 1, except that the shaft rotation speed in the emulsification and dispersion treatment using a homogenizer was set to 4000 rpm and 5000 rpm. The room temperature during the emulsification and dispersion treatment was 24.8°C.

Particle size distribution measurements were performed on these emulsions E1 and E2. Here, the weight average diameter was measured using a measurement system consisting of a particle size distribution measuring device, Microtrac MT3300EXII, manufactured by Nikkiso Co., Ltd., equipped with a liquid circulation pump, Microtrac USVR, also manufactured by Nikkiso Co., Ltd.

Figure 19 is a graph showing the results of particle size distribution measurements performed on emulsions E1 and E2. In Figure 19, curve C1 represents the particle size distribution of emulsion E1, and curve C2 represents the particle size distribution of emulsion E2. As a result of this particle size distribution measurement, the average particle size of dispersed particles in emulsion E1 was 49.8 μm, and the average particle size of dispersed particles in emulsion E2 was 28.1 μm.

<Preparation of Sample 1>
75 μL of emulsion E1 was collected using a micropipette. This was spread and filled into a liquid-reservoir cell prepared in the same manner as in Test 1, to form a film made of the first emulsion (i.e., a first liquid film) having a thickness of about 187.5 μm, calculated taking into account the specific gravity.

Next, the entire first liquid film was irradiated with ultraviolet light at an illuminance of 4.6 mW/cm ² for 30 seconds, thereby exposing the first liquid film to an integrated light amount of 138 mJ/cm ^2. As a result, the first liquid was polymerized in the area irradiated with the ultraviolet light, forming a porous layer made of a cured product of the first dispersed particles.

Then, the liquid storage cell with the porous layer formed was placed on a hot plate heated to 80°C with a spacer between them. The spacer used was one that provided a distance of 1 mm between the hot plate and the liquid storage cell. In this state, the cell was dried by heating for 10 minutes. In this manner, the porous layer was dried.

75 μL of emulsion E2 was collected using a micropipette and dropped onto the porous layer, allowing it to spread, forming a membrane of the second emulsion (i.e., the second liquid membrane) with a thickness of approximately 187.5 μm, calculated taking into account the specific gravity.

Next, a copper mask having a thickness of 0.25 mm and a slit-shaped opening having a width of 2 mm was placed on the second liquid film via an aluminum spacer having a thickness of 1 mm so as not to come into contact with the liquid surface. Next, a UV parallel light exposure machine (UVC-2502S manufactured by SAN-EI ELECTRONIC) was used to irradiate ultraviolet light with an illuminance of 4.6 mW/ ^cm2 from above the mask for 8 seconds, thereby exposing the second liquid film to an integrated light quantity of 36.8 mJ/ ^cm2 . This caused the third liquid to polymerize in the area irradiated with the ultraviolet light, forming a granular layer made of a cured product of the second dispersed particles.

Then, the liquid storage cell with the granular layer formed was placed on a hot plate heated to 80°C with a spacer between them. The spacer used was one that provided a distance of 1 mm between the hot plate and the liquid storage cell. In this state, the cell was dried by heating for 10 minutes. In this manner, the granular layer was dried.

Finally, the entire laminate structure including the porous layer and the granular layer was irradiated with ultraviolet light at an illuminance of 4.6 mW/cm ² for 90 seconds, thereby providing an integrated light exposure of 414 mJ/cm ^2. The pattern was fixed in this manner to obtain Sample 1.

<Preparation of Sample 2>
Sample 2 was prepared in the same manner as Sample 1, except that the amount of Emulsion E2 was changed from 75 μL to 82 μL.

<Preparation of Sample 3>
Sample 3 was prepared in the same manner as Sample 1, except that the amount of Emulsion E2 was changed from 75 μL to 90 μL.

<Preparation of Sample 4>
Sample 4 was prepared in the same manner as Sample 1, except that the amount of Emulsion E2 was changed from 75 μL to 100 μL.

<Preparation of Sample 5>
Sample 5 was prepared in the same manner as Sample 1, except that the amount of Emulsion E2 was changed from 75 μL to 112 μL.

<Preparation of Sample 6>
Sample 6 was prepared in the same manner as sample 1, except that 75 μL of emulsion E2 was used instead of 75 μL of emulsion E1 to form the first liquid film, and 75 μL of emulsion E1 was used instead of 75 μL of emulsion E2 to form the second liquid film.

<Preparation of Sample 7>
Sample 7 was prepared in the same manner as Sample 1, except that 75 μL of emulsion E2 was used instead of 75 μL of emulsion E1 to form the first liquid film, and 112 μL of emulsion E1 was used instead of 75 μL of emulsion E2 to form the second liquid film.

<Results expected from the mechanism>
The shape accuracy of the pattern film is affected by the migration speed of the third liquid to the porous layer and granular layer, i.e., the change in the permeation volume over time, as explained with reference to Figures 6 and 7. The only emulsions used to prepare samples 1 to 7 were emulsions E1 and E2. Emulsions E1 and E2 have the same composition but different average particle sizes of dispersed particles. The average particle size of dispersed particles affects the change in the permeation volume over time. Therefore, in this test, it is considered that it is the average particle size of dispersed particles that affects the shape accuracy of the pattern film.

Generally, the following formula (1), known as the Lucas-Washburn formula, is often used to analyze liquid penetration into a porous body, where _Lp is the penetration depth of the liquid, t is time, e is the capillary radius, γ is the surface tension of the liquid, η is the viscosity of the liquid, and cos θ is the contact angle between the liquid and the capillary surface.

From formula (1), it can be seen that the larger the capillary radius e, the higher the rate at which liquid penetrates the pores of the porous body. A porous body obtained from an emulsion with a large average particle size of dispersed particles has a larger pore diameter than a porous body obtained from an emulsion with a small average particle size of dispersed particles. The pores in the porous body can be considered to be a collection of capillaries. Therefore, it is expected that the pattern films of samples 1 to 5 have higher shape accuracy than samples 6 and 7.

A simulation was performed on the time-dependent change in the penetration depth and penetration volume of the third liquid into the porous body when one of emulsions E1 and E2 was used as the first emulsion and the other was used as the second emulsion. This is described below.

When calculating the change over time in the penetration depth _Lp of the liquid from equation (1), it is necessary to determine the capillary radius e, the surface tension γ of the liquid, the viscosity η of the liquid, and the contact angle cos θ between the liquid and the capillary surface.

According to the catalog value, the viscosity of trimethylolpropane triacrylate is 100 mPa·s (25°C). Therefore, this catalog value is used as the viscosity η of the liquid. In addition, the contact angle cos θ between the liquid and the capillary surface is assumed to be 1, since trimethylolpropane triacrylate and its cured product are composed of the same oligomer components.

There is a Maclead relationship between the surface tension γ _L and density of a liquid, expressed by the following formula (2): where C is a constant specific to the substance, ρ _L is the density of the saturated liquid (g/cm ³ ), and ρ _V is the density of the saturated vapor (g/cm ³ ).

The constant C is a value determined by the chemical structure and is defined as Parachor P by the following formula (3), where M is the molecular weight.

The liquid used (trimethylolpropane triacrylate) is an oligomer, and the density ρ _V of the saturated vapor is much smaller than the density ρ _L of the saturated liquid. Therefore, the density ρ _V of the saturated vapor can be ignored, and the following formula (4) can be derived from formula (3).

The surface tension γ _L of trimethylolpropane triacrylate was estimated to be 37.0 mN/m by adding up the additive factors for the atomic groups of parachor. The molecular weight of trimethylolpropane triacrylate was 296.3, and the density ρ _L of the saturated liquid was 1.11 (g/mL).

If we assume that the particles in the porous body formed by agglomeration are packed hexagonally close-packed, the packing rate is 74.05% by volume and the void rate is 25.95% by volume. For simplicity, we assume that the particles in the porous body are packed hexagonally close-packed, and that the particle-packed portions and voids are each cylindrical. Based on the above assumptions, we derived the following formula (6) from the following formula (5). Here, f is the radius of the cylinder when the particle-packed portion is assumed to be cylindrical. e is the radius of the cylinder when the voids are assumed to be cylindrical. L is the length of the cylinder.

Assuming that the radius f is half the average particle size of the dispersed particles in the emulsion, the radii f and e shown in Table 1 below can be calculated from formula (6) for the porous bodies obtained from emulsions E1 and E2.

Equation (1) can be converted to the following equation (7).

From equation (7) and the above values, the relationship between the penetration depth _Lp and the elapsed time is obtained as shown in Fig. 20. In Fig. 20, curves C3 and C4 show the above relationship obtained for the porous bodies obtained from emulsions E1 and E2, respectively.

The relationship between the permeation volume V _e and the elapsed time can be expressed by the following formula (8): Here, the permeation volume V _e is the volume of liquid that permeates into one capillary tube having a cylindrical shape.

From equations (7) and (8) and the above values, the relationship between the permeation volume V _e and the elapsed time can be obtained as shown in Fig. 21. In Fig. 21, curves C5 and C6 show the above relationship obtained for the porous bodies obtained from emulsions E1 and E2, respectively.

As shown in Figures 20 and 21, the third liquid is expected to penetrate the porous body obtained from emulsion E1 at a higher rate than the porous body obtained from emulsion E2. Therefore, it is expected that the pattern films of samples 1 to 5 have higher shape accuracy than samples 6 and 7.

<Imaging stacked structures>
Using a digital camera (L-835 manufactured by HOZAN) equipped with a zoom lens (L-815 manufactured by HOZAN), each of Samples 1 to 7 was illuminated from diagonally above and photographed from diagonally above to the right to capture the surface of each layered structure. The images thus obtained are shown in Figs. 22 to 28.
As is clear from a comparison of Figures 22 to 28 with Figures 9 to 18, when a porous layer was formed, a pattern film with superior shape accuracy was formed compared to when the porous layer was omitted.

<Three-dimensional shape measurement>
For each of Samples 1 to 7 in which gold was sputtered onto the laminated structure, a three-dimensional image and a cross-sectional profile of the laminated structure surface were obtained using a one-shot 3D shape measuring device manufactured by Keyence Corp. Some of the results are shown in Figs. 29 and 30 and Table 2.

In FIG. 29, curves C7 and C8 represent the cross-sectional profiles obtained for samples 1 and 6, respectively. Also, in FIG. 30, curves C9 and C10 represent the cross-sectional profiles obtained for samples 5 and 7, respectively.

As is clear from a comparison of the results obtained for Samples 1 and 6 and a comparison of the results obtained for Samples 5 and 7, when the average particle size of the first dispersed particles was larger than that of the second dispersed particles, the maximum slope in the cross-sectional profile was larger than when the average particle size of the first dispersed particles was smaller than that of the second dispersed particles. This result is consistent with the above result expected from the mechanism.
The invention as originally claimed is set forth below.
[1]
forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with active energy rays on a base having a plurality of recesses;
irradiating the film with the active energy rays in a pattern to harden the first liquid in the region irradiated with the active energy rays;
removing at least a portion of the second liquid from the film after the irradiation with the active energy rays;
hardening the unhardened first liquid contained in the film from which at least a portion of the second liquid has been removed;
A method for forming a patterned film comprising the steps of:
[2]
forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with active energy rays on a base having a plurality of recesses such that the plurality of recesses are not completely filled with the emulsion;
irradiating the film with the active energy rays in a pattern to form a particulate layer made of a cured product of the dispersed particles in the area irradiated with the active energy rays;
After the irradiation of the active energy rays, at least a portion of the second liquid is removed from the film, and at least a portion of the uncured first liquid in the area not irradiated with the active energy rays is moved into gaps in the granular layer and into the plurality of recesses.
Then, the uncured first liquid is cured.
A method for forming a patterned film comprising the steps of:
[3]
3. The method according to item 1 or 2, wherein the base is porous.
[4]
forming a first film on a substrate, the first film being made of a first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray;
irradiating the first film with the first active energy ray to harden the first liquid;
removing the second liquid from the first film after irradiation with the first active energy ray to obtain a porous layer made of a cured product of the first liquid;
forming a second film on the porous layer, the second film being made of a second emulsion including second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray, and a second dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray;
irradiating the second film with the second active energy rays in a pattern to harden the third liquid in the region irradiated with the second active energy rays;
removing at least a portion of the fourth liquid from the second film after the irradiation of the second active energy ray;
hardening the unhardened third liquid contained in the second film from which at least a portion of the fourth liquid has been removed;
A method for forming a patterned film comprising the steps of:
[5]
forming a first film on a substrate, the first film being made of a first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray;
irradiating the first film with the first active energy ray to form a porous layer made of a cured product of the first dispersed particles;
removing the second liquid from the porous layer;
forming a second film on the porous layer, the second film being made of a second emulsion including second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray, and a second dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray;
irradiating the second film with the second active energy ray in a pattern to form a granular layer made of a cured product of the second dispersed particles in an area irradiated with the second active energy ray; removing at least a portion of the fourth liquid from the second film after irradiation with the second active energy ray, and transferring at least a portion of the uncured third liquid in an area not irradiated with the second active energy ray into the granular layer and the porous layer;
Then, the uncured third liquid is cured.
A method for forming a patterned film comprising the steps of:
[6]
Item 6. The method according to item 4 or 5, wherein the first dispersed particles have a larger average particle size than the second dispersed particles.
[7]
7. The method according to any one of items 4 to 6, wherein each of the first emulsion and the second emulsion is an oil-in-water emulsion.
[8]
8. The method according to any one of items 4 to 7, wherein the irradiation of the first active energy ray is performed such that at least a part of a region of the second film that is irradiated with the first active energy ray and at least a part of a region of the second film that is not irradiated with the first active energy ray are located on the porous layer.
[9]
Item 9. A patterned film formed by the method according to any one of items 1 to 8.
[10]
A base having a plurality of recesses;
a particulate layer partially covering the substrate;
a hardened material at least partially filling the recesses and the gaps in the granular layer;
A structure comprising:

DESCRIPTION OF SYMBOLS 1... Base material, 2a1... First film, 2a2... Second film, 2b1... Porous layer, 2b2... Granular layer, 2B1... First layer, 2B2... Second layer, 21a1... First dispersed particles, 21a2... Th. 2-dispersed particles, 21a2'... combined body, 21b1... cured product, 21b2... cured product, 21b2'... polymerized phase, 22a1... first dispersion medium, 22a2... second dispersion medium, C1... curve, C2... curve, C3... Curve, C4...Curve, C5...Curve, C6...Curve, C7...Curve, C8...Curve, C9...Curve, C10...Curve.

Claims (9)

forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with active energy rays on a base having a plurality of recesses;
irradiating the film with the active energy rays in a pattern to harden the first liquid in the region irradiated with the active energy rays;
removing at least a portion of the second liquid from the film by drying the film after the irradiation of the active energy rays;
and curing the uncured first liquid contained in the film from which at least a portion of the second liquid has been removed. forming a film made of an emulsion containing dispersed particles containing a first liquid that is cured by irradiation with active energy rays and a dispersion medium containing a second liquid that is not cured by irradiation with active energy rays on a base having a plurality of recesses such that the plurality of recesses are not completely filled with the emulsion;
irradiating the film with the active energy rays in a pattern to form a particulate layer made of a cured product of the dispersed particles in the area irradiated with the active energy rays;
After the irradiation of the active energy rays, the film is dried to remove at least a portion of the second liquid from the film, and at least a portion of the uncured first liquid in areas not irradiated with the active energy rays is moved into gaps in the granular layer and into the plurality of recesses.
and then curing the uncured first liquid. The method according to claim 1 or 2, wherein the substrate is porous. forming a first film on a substrate, the first film being made of a first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray;
irradiating the first film with the first active energy ray to harden the first liquid;
removing the second liquid from the first film after irradiation with the first active energy ray to obtain a porous layer made of a cured product of the first liquid;
forming a second film on the porous layer, the second film being made of a second emulsion including second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray, and a second dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray;
irradiating the second film with the second active energy rays in a pattern to harden the third liquid in the region irradiated with the second active energy rays;
removing at least a portion of the fourth liquid from the second film by drying the second film after the irradiation of the second active energy rays;
and curing the uncured third liquid contained in the second film from which at least a portion of the fourth liquid has been removed. forming a first film on a substrate, the first film being made of a first emulsion including first dispersed particles including a first liquid that is cured by irradiation with a first active energy ray, and a first dispersion medium including a second liquid that is not cured by irradiation with the first active energy ray;
irradiating the first film with the first active energy ray to form a porous layer made of a cured product of the first dispersed particles;
drying the porous layer to remove the second liquid from the porous layer;
forming a second film on the porous layer, the second film being made of a second emulsion including second dispersed particles including a third liquid that is cured by irradiation with a second active energy ray, and a second dispersion medium including a fourth liquid that is not cured by irradiation with the second active energy ray;
irradiating the second film with the second active energy ray in a pattern to form a particulate layer made of a cured product of the second dispersed particles in the region irradiated with the second active energy ray;
After the irradiation of the second active energy ray, the second film is dried to remove at least a portion of the fourth liquid from the second film, thereby moving at least a portion of the uncured third liquid in an area not irradiated with the second active energy ray into the granular layer and the porous layer.
and then curing the uncured third liquid. The method according to claim 4 or 5, wherein the first dispersed particles have a larger average particle size than the second dispersed particles. The method according to any one of claims 4 to 6, wherein each of the first emulsion and the second emulsion is an oil-in-water emulsion. The method according to any one of claims 4 to 7, wherein the irradiation of the second active energy ray is performed so that at least a part of the region of the second film that is irradiated with the second active energy ray and at least a part of the region of the second film that is not irradiated with the second active energy ray are located on the porous layer. A patterned film formed by the method according to any one of claims 1 to 8.