TW201728434A - Water-repellent member and manufacturing method for same - Google Patents

Abstract

The purpose of the present invention is to provide a water-repellent member having excellent water-repelling properties and scratch resistance. The present invention provides a water-repellent member comprising a base material and a resin layer on at least one surface of the base material. The resin layer has a primary peak-valley shape in which a plurality of recesses are provided on the base surface, with the proportion of such recesses by area in the base area being 10-60%. The base surface is provided with a secondary peak-valley shape, and the average height of the secondary peak-valley shape is 15 nm or greater, and the surface of the secondary peak-valley shape is provided with a fluorine-containing group.

Description

Waterproof component and method of manufacturing same

The present invention relates to a water repellent member and a method of manufacturing the same.

Patent Document 1 discloses a water-repellent member in which a plurality of columnar protrusions are formed on a surface and inorganic particles are exposed on the surface of the columnar protrusions. Patent Document 2 discloses a water-repellent member in which a plurality of tapered or frustum-like projections are formed on a surface, and hydrophobic fine particles are adhered to the surface of the projection.

[Prior Art Literature] [Patent Literature]

Patent Document 1] WO2014/181448

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-122435

The water-repellent members of Patent Documents 1 to 2 are all premised on the formation of protrusions on the surface of the water-repellent member. Therefore, in the water-repellent members of Patent Documents 1 to 2, if the surface is rubbed, the protrusion collapses, and the water repellency is lowered.

The present invention has been made in view of such circumstances, and provides a water-repellent member excellent in water repellency and scratch resistance.

The present invention provides a water repellent member having a substrate and a resin layer on at least one side of the substrate, the resin layer having a primary concavo-convex shape in which a plurality of concave portions are provided on a base surface, the concave portion a ratio of an area on the base surface is 10 to 60%, and a secondary uneven shape is provided on the base surface, and an average height of the secondary uneven shape is 15 nm or more, and the second uneven shape is The surface is provided with a fluorine-containing group.

The present inventors have found that by making the area ratio of the concave portion on the base surface of the resin layer within a specific range, a secondary uneven shape is formed on the base surface, and fluorine is provided on the surface of the secondary uneven shape. The group can improve both water repellency and scratch resistance, and the present invention has been completed.

Hereinafter, various embodiments of the present invention will be listed. The embodiments shown below can be combined with each other.

Preferably, the fluorine-containing group is provided on the surface of the secondary uneven shape via an inorganic substance.

Preferably, the recess is a hole provided in an island shape.

Preferably, the pores have a cross-sectional area on the substrate of 400 π nm ² to 3600 π μm ² .

Preferably the aperture is cylindrical.

Preferably, the fluorine-containing group is a perfluoroalkyl group.

Preferably, the contact angle with respect to water is 160 degrees or more.

According to another aspect of the present invention, there is provided a method for producing a water repellent member comprising the steps of: coating a raw material composition obtained by mixing a photocurable resin composition and inorganic particles on a substrate to form a transferred layer. In a state where the mold is pressed against the transferred layer, the transfer layer is irradiated with an active energy ray to cure the transferred layer to form a resin layer having an uneven shape, and the resin layer is formed. The step of etching to expose the inorganic particles on the surface to form a fluorine-containing layer by reacting the inorganic particles with a fluorine-containing decane coupling agent to cover the inorganic particles.

Preferably, the inorganic particles have an average particle diameter (D50) of 5 to 400 nm.

1‧‧‧Waterproof parts

3‧‧‧ hole

4‧‧‧ concave shape

4a‧‧‧ hole

6‧‧‧Substrate

7‧‧‧ resin layer

7a‧‧‧ base

7b‧‧‧ Protrusion

8‧‧‧Inorganic particles

9‧‧‧Fluorin layer

11‧‧‧Transfer layer

13‧‧‧Mold

15‧‧‧ flip pattern

17‧‧‧Active energy ray

Fig. 1 shows a water-repellent member 1 according to a first embodiment of the present invention. Fig. 1(a) is a plan view, Fig. 1(b) is a cross-sectional view taken along line AA, and Fig. 1(c) is a view for explaining an area ratio of a concave portion. Top view of the calculation method.

2(a) to 2(e) show the steps of manufacturing the waterproof member 1 according to the first embodiment of the present invention.

3(a) to 3(d) show the steps of manufacturing the waterproof member 1 according to the second embodiment of the present invention.

4(a) to 4(d) show the manufacturing steps of the water repellent member 1 according to the third embodiment of the present invention, and Fig. 4(e) is an enlarged view of the area A in (d).

5(a) to 5(b) show SEM images of the water-repellent film of Example 1 and Example 3, respectively.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1. First embodiment 1-1. Waterproof parts

As shown in Fig. 1, a water-repellent member 1 according to a first embodiment of the present invention includes a base material 6 and a resin layer 7 on at least one surface of the base material 6, and the resin layer 7 has a plurality of concave portions provided on the base surface 7a. In the primary concavo-convex shape, the area ratio of the concave portion on the base surface 7a is 10 to 60%, and the base surface 7a is provided with a secondary uneven shape, and the average height of the secondary uneven shape is 15 nm or more. The surface is provided with a fluorine-containing group.

Hereinafter, each structure will be described in detail.

<Waterproof part 1>

The form of the water repellent member 1 is not particularly limited, but a flexible water repellent film is preferable. The contact angle of the water repellent member 1 with respect to water is not particularly limited, but is preferably 160 degrees or more, more preferably 170 degrees or more, further preferably 175 degrees or more, and still more preferably 178 degrees or more. It is preferable that the waterproof member 1 also has oil repellency.

<Substrate 6>

The material of the substrate 6 is not particularly limited, but a transparent substrate such as a resin substrate or a quartz substrate is preferable, and a resin substrate is more preferable from the viewpoint of flexibility. The resin constituting the resin substrate is, for example, selected from the group consisting of polyethylene terephthalate, polycarbonate, polyester, polyolefin, polyimine, polyfluorene, polyether fluorene, cyclic polyolefin, and One of polyethylene naphthalate. Further, the substrate 6 is preferably in the form of a flexible film, and preferably has a thickness in the range of 25 to 500 μm.

<Resin layer 7, primary uneven shape>

The resin constituting the resin layer 7 is not particularly limited, and is made of, for example, a resin such as a (meth)acrylic resin, a styrene resin, an olefin resin, a polycarbonate resin, a polyester resin, an epoxy resin, or an anthrone resin.

The primary uneven shape is configured such that a plurality of concave portions are provided on the base surface 7a. In the present embodiment, the concave portion is a hole 3 provided in an island shape, and the primary uneven shape is a hole pattern shape in which a plurality of holes 3 are dispersed. On the other hand, the shape of the concave portion is not particularly limited, and may be, for example, a groove shape. In this case, the primary uneven shape is a line and space pattern in which a plurality of groove-shaped recesses are provided in substantially parallel directions.

In the present embodiment, the hole 3 is a columnar shape whose cross-sectional area is substantially constant in the depth direction. On the other hand, the hole 3 may have a tapered shape, a truncated cone shape or the like. Further, it is preferable that the cross-sectional shape of the hole 3 is a circular shape, but may be other shapes such as an ellipse, an ellipse, a polygon (a square, a rectangle, a regular hexagon, or the like). When the cross-sectional shape of the hole 3 is circular, the diameter thereof is preferably 40 nm to 120 μm, more preferably 80 nm to 10 μm, still more preferably 100 nm to 3 μm. Specifically, the lower limit of the diameter is, for example, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, or 230 nm. Specifically, the upper limit of the diameter is, for example, 1.7, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 40, 60, 80, 100, or 120 μm. The cross-sectional area at a diameter of 40 nm is 400 π nm ² , and the cross-sectional area at a diameter of 120 μm is 3600 π μm ² . When the cross-sectional shape of the hole 3 is other than 円, it is preferable to have the same cross-sectional area as in the case of a circle. Therefore, it is preferable that the cross-sectional area of the pores 3 is 400 π nm ² to 3600 π μm ² irrespective of the cross-sectional shape.

The primary uneven shape is formed such that the area ratio (depression ratio) of the concave portion on the base surface 7a is 10 to 60%. If the dent rate is too small, the water repellency is lowered. If the dent rate is too large, the water repellency is lowered and the scratch resistance is also lowered. The depression rate can pass through the region in which the primary concavo-convex shape is formed (the concave on the base surface 7a) The area of the portion) / (the area of the region in which the primary uneven shape is formed) is calculated. In the case where the primary uneven shape is constituted by the repetition of the unit cells, the recess ratio can be obtained by calculating the area ratio of the concave portions in the unit cells. In the present embodiment, the region T of the equilateral triangle in FIG. 1(c) is a unit cell, and the oblique line portion S in the region T is the area of the hole 3, and therefore, can pass (area of the oblique line portion S) / (region T Area) Calculate the sag rate. Specifically, the dent rate is, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60%, and may be within a range between any two of these numerical values.

The average height of the primary uneven shape is not particularly limited, but is preferably, for example, 60 nm to 100 μm, more preferably 80 nm to 10 μm, still more preferably 100 nm to 3 μm. Specifically, the lower limit of the average height is, for example, 60, 80, 100, 120, 140, 160, 180, 190, or 200 nm. Specifically, the upper limit of the average height is, for example, 1.6, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 40, 60, 80, or 100 μm. The ratio of the average height to the diameter of the primary uneven shape is not particularly limited, but is preferably, for example, 0.5 to 2, and more preferably 0.7 to 1.5. When the value is within the above range, water repellency and scratch resistance are easily improved. Specifically, the ratio is, for example, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, and may be any two of these values. Within the range between values. The average height of the primary shape is an average value obtained by observing an image obtained by observation with a scanning probe microscope (L-trace, manufactured by SII NanoTechnology Co., Ltd.) using a scanning probe microscope PC software "SPIWin", for example In the cross-sectional profile at the time of the recess formed by the plurality of transfers, the heights of the adjacent irregularities at 5 points were randomly extracted, and the average value was calculated.

<Secondary concavo-convex shape, fluorine-containing group, inorganic substance>

A secondary uneven shape is provided on the base surface 7a. In the present embodiment, the secondary uneven shape is formed by the inorganic particles 8 provided on the base surface 7a. More specifically, in the present embodiment, a plurality of inorganic particles 8 are embedded in the resin layer 7, and a part of the plurality of inorganic particles 8 protrudes from the base surface 7a and is exposed from the resin layer 7. Further, the outer peripheral surface of the inorganic particles 8 protruding from the base surface 7a forms a secondary uneven shape. It is also possible to form a secondary uneven shape in the concave portion of the resin layer 7, but it is not essential.

In the present embodiment, the fluorine-containing layer 9 containing a fluorine-containing group is provided to cover the exposed surface of the inorganic particles 8. Therefore, in the present embodiment, the fluorine-containing group is provided on the surface of the secondary uneven shape via the inorganic substance. The fluorine-containing layer 9 may contain a fluorine-containing group, and its thickness or structure is not limited. Water repellency is improved by providing the fluorine-containing layer 9. The fluorine-containing group is, in one example, a perfluoroalkyl group, and more specifically, a perfluoroalkylalkyl group. The number of carbon atoms of the perfluoroalkyl group is, for example, 1 to 10, and specifically, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and any two of the numerical values listed herein may be used. Between the limits. Preferably, the fluorine-containing group is chemically bonded to the inorganic particles 8. The inorganic particles 8 have high adhesion to the resin layer 7, and the fluorine-containing group and the inorganic particles 8 easily form a strong chemical bond. Therefore, the fluorine-containing layer 9 is provided by providing the fluorine-containing layer 9 so as to cover the exposed surface of the inorganic particles 8. Firmly held on the secondary concave and convex shape. Further, it is preferable that the fluorine-containing layer 9 is also disposed on the surface of the secondary shape formed in the hole 3, and may be disposed outside the surface of the secondary uneven shape.

The inorganic particles 8 are inorganic particles, and examples of the inorganic material include a metal element, an inorganic oxide film, an inorganic nitride film, and an inorganic oxynitride film. Examples of the inorganic element constituting the inorganic substance include Si and Al. The inorganic substance is, for example, cerium oxide or aluminum oxide, and in order to further improve the scratch resistance, alumina is preferably used.

The average particle diameter of the inorganic particles 8 is not particularly limited, and is, for example, 5 to 400 nm. When the average particle diameter of the inorganic particles 8 is within this range, the water repellency tends to be high. Specifically, the average particle diameter of the inorganic particles 8 is, for example, 5, 10, 15, 20, 25, 50, 100, 150, 200, 250, 300, 350, 400 nm, and any two of these values may be used. In the range between, here, the average particle diameter in the present invention means that when the powder is divided into two parts according to a certain particle diameter, the larger and smaller ones have the same diameter (D50), and the inorganic particles. The average particle diameter of 8 means a value obtained by dynamic light scattering.

The average height of the secondary uneven shape is 15 nm or more. The secondary uneven shape exhibits excellent water repellency by having such an average height. The upper limit of the average height is not particularly limited, for example, 1000 nm. Therefore, the average height is preferably from 15 to 1000 nm, more preferably from 40 to 500 nm. Specifically, the average height is, for example, 15, 20, 25, 30, 35, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 200, 500, 1000 nm, and may also be at these values. The range between any two values. The average height of the secondary shape is an average value obtained by observation by a scanning probe microscope (L-trace, manufactured by SII NanoTechnology Co., Ltd.). The image was measured using a scanning probe microscope PC software "SPIWin", and the height of five adjacent concavities and convexities was randomly extracted from the cross-sectional profile of the concave portion formed by, for example, transfer, and the average value was calculated.

1-2. Method of manufacturing waterproof member

Next, a method of manufacturing the waterproof member 1 will be described with reference to Fig. 2 .

The method for producing the water repellent member 1 according to the first embodiment of the present invention includes a transfer layer forming step, a concavo-convex shape forming step, an etching step, and a fluorine-containing layer forming step.

Hereinafter, each step will be described in detail.

<Transfer layer formation step>

First, as shown in FIG. 2(a), a raw material composition obtained by mixing a photocurable resin composition and inorganic particles 8 is applied onto a substrate 6, to form a transferred layer 11. The details of the substrate 6 and the inorganic particles 8 are as described above. The photocurable resin composition contains a monomer and a photoinitiator, and has a property of being cured by irradiation with an active energy ray. The "active energy ray" is a general term for energy rays that can cure a photocurable resin composition such as UV light, visible light, or electron beam.

Examples of the monomer include photopolymerizable monomers for forming a (meth)acrylic resin, a styrene resin, an olefin resin, a polycarbonate resin, a polyester resin, an epoxy resin, an anthrone resin, and the like, and photopolymerization is preferred. Sexual (meth)acrylic monomer. Further, in the present specification, (meth)acrylic acid means methacrylic acid and/or acrylic acid, and (meth)acrylic acid ester means methacrylic acid ester and/or acrylate.

The photoinitiator is a component added to promote polymerization of the monomer, and is preferably contained in an amount of 0.1 part by mass or more based on 100 parts by mass of the monomer. The upper limit of the content of the photoinitiator is not particularly limited, and is, for example, 20 parts by mass based on 100 parts by mass of the above monomer.

The photocurable resin composition may contain a solvent, a polymerization inhibitor, a chain transfer agent, an antioxidant, a photosensitizer, a filler, a leveling agent, and the like, within a range that does not affect the properties of the photocurable resin composition.

The mass ratio of the inorganic particles 8 to the photocurable resin composition in the raw material composition is not particularly limited, and is, for example, 0.05 to 0.5. Specifically, the mass ratio may be, for example, within a range between any two of the numerical values listed below: 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, and 0.5.

The raw material composition can be produced by mixing the above components by a known method. The raw material composition can be applied onto the substrate 6 by spin coating, spray coating, bar coating, dip coating, die coating, and slit coating to form the transferred layer 11.

<Concave shape forming step>

Next, as shown in FIGS. 2(a) to 2(c), the transfer layer 11 is cured by irradiating the transfer layer 11 with the active energy ray 17 in a state where the mold 13 is pressed against the transfer layer 11. The resin layer 7 having the uneven shape 4 is formed. The uneven shape 4 is a shape having a plurality of holes 4a having a depth and a diameter smaller than that of the holes 3 on the base surface 7, and the mold 13 is provided with an inverted pattern 15 of the uneven shape 4.

The type of the mold 13 is not particularly limited, and for example, a resin mold, a nickel mold, or the like can be used. The pressure at which the mold 13 is pressed onto the transfer layer 11 may be a pressure that can transfer the shape of the reverse pattern 15 onto the transfer layer 11. The active energy ray 17 irradiated to the transfer layer 11 may be irradiated with a cumulative amount of light that is sufficiently cured by the transfer layer 11, and the cumulative amount of light is, for example, 100 to 10000 mJ/cm ² . The transferred layer 11 is cured by the irradiation of the active energy ray 17. In the present embodiment, the irradiation of the active energy ray 17 is performed from the side of the substrate 6, but the irradiation of the active energy ray 17 may be performed from the side of the mold.

Next, as shown in FIG. 2(c), the mold 13 is removed, and a structure in which the resin layer 7 having the uneven shape 4 is formed on the substrate 6 is obtained. At this time, the inorganic particles 8 are buried in the resin layer 7, and the secondary uneven shape is not formed on the base surface 7a.

Next, as shown in FIG. 2(c) to FIG. 2(d), the base surface 7a of the resin layer 7 is retreated by etching, and the inorganic particles 8 embedded in the resin layer 7 are exposed from the surface and protrude from the base surface 7a. . Further, the outer peripheral surface of the inorganic particles 8 protruding from the base surface 7a forms a secondary uneven shape. At this time, the hole 4a is expanded to the hole 3.

The method of etching is not particularly limited, and may be wet etching or dry etching. As an example of dry etching, Oxygen plasma ashing can be cited.

<Fluorine layer forming step>

Next, as shown in FIG. 2(e), the fluorine-containing layer 9 is formed by reacting the inorganic particles 8 with the fluorine-containing decane coupling agent to cover the inorganic particles 8, thereby completing the manufacture of the water-repellent member 1 of the present embodiment. . The fluorine-containing decane coupling agent is, for example, a perfluoroalkyltrialkoxy group (methoxy group, ethoxy group, etc.) decane. An example of the fluorine-containing decane coupling agent is OPTOOL DSX (manufactured by Daikin Industries, Ltd.).

2. Second embodiment

The waterproof member 1 of the second embodiment of the present invention will be described with reference to Fig. 3 . The water-repellent member 1 of the present embodiment is similar to the first embodiment, but as shown in FIG. 3(d), in the water-repellent member 1 of the present embodiment, the inorganic particles 8 are not embedded in the resin layer 7, but are Adhered to the surface of the resin layer 7. Further, a secondary uneven shape is formed on the base surface 7a of the resin layer 7 by adhering a plurality of inorganic particles 8 to the base surface 7a of the resin layer 7.

Hereinafter, a method of manufacturing the waterproof member 1 of the present embodiment will be described. The method for producing the water repellent member 1 of the present embodiment includes a transfer layer forming step, a concavo-convex shape forming step, and inorganic particle adhesion and fluorine layer forming steps.

<Transfer layer formation step>

In this step, as shown in FIG. 3(a), a raw material composition containing a photocurable resin composition is applied onto a substrate 6 to form a transferred layer 11. In the present embodiment, the raw material composition must contain a photocurable resin composition, and it is not necessary to contain inorganic particles.

<Concave shape forming step>

In this step, as shown in FIGS. 3(b) to 3(c), the transfer layer 11 is irradiated with the active energy ray 17 in a state where the mold 13 is pressed against the transfer layer 11, so that the transfer is performed. The layer 11 is cured to form a resin layer 7 having a concavo-convex shape 4. In the present embodiment, the uneven shape 4 is a shape having a plurality of holes 3 on the base surface 7a.

<Inorganic particle adhesion and fluorine layer formation step>

In this step, as shown in FIG. 3(d), a secondary uneven shape is formed on the base surface 7a of the resin layer 7 by attaching a plurality of inorganic particles 8 to the base surface 7a of the resin layer 7. Further, it is preferred that the inorganic particles 8 also adhere to the pores 3.

The inorganic particles 8 may or may not have a fluorine-containing layer 9 on the surface. In the former case, the production of the water repellent member 1 of the present embodiment is completed by attaching the inorganic particles 8 containing the fluorine-containing layer 9 to the base surface 7a. In the latter case, after the inorganic particles 8 are adhered to the base surface 7a, the production of the water-repellent member 1 of the present embodiment is completed by performing the same fluorine-containing layer forming step as in the first embodiment. In order to facilitate adhesion of the inorganic particles, for example, a precursor of an inorganic substance such as an alkoxide may be added to the dispersion of the inorganic particles.

This embodiment can also be implemented in the following manner.

‧ It is also possible to use organic particles having the same average particle diameter as the inorganic particles 8 instead of the inorganic particles 8. In this case, after the organic particles are attached to the base surface 7a, an inorganic film can be formed on the surface of the organic particles, and thereafter, the same fluorine-containing layer forming step as in the first embodiment can be performed. The inorganic film is composed of the same inorganic material as the inorganic particles 8, and can be formed by a method such as vapor deposition or sputtering.

‧ It is also possible to use the polymer particles composed of the fluoroalkyl decane polymer having the same average particle diameter as the inorganic particles 8 instead of the inorganic particles 8. In this case, the secondary uneven shape can be formed by adhering the polymer particles to the base surface 7a. A fluorine-containing group is provided on the surface of the polymer particles, and therefore the surface of the secondary uneven shape formed of the polymer particles is also provided with a fluorine-containing group.

3. Third embodiment

The waterproof member 1 of the third embodiment of the present invention will be described with reference to Fig. 4 . The water-repellent member 1 of the present embodiment is similar to the second embodiment, and as shown in Figs. 4(d) to 4(e), in the waterproof member 1 of the present embodiment, on the base surface 7a of the resin layer 7 The resin layer 7 itself is molded to form a secondary uneven shape on the base surface 7a.

Hereinafter, a method of manufacturing the waterproof member 1 of the present embodiment will be described. The method for producing the water-repellent member 1 of the present embodiment includes a transfer layer forming step, a concavo-convex shape forming step, and an inorganic film formation and a fluorine-containing layer forming step.

<Transfer layer formation step>

In this step, as shown in FIG. 4(a), a raw material composition containing a photocurable resin composition is applied onto a substrate 6 to form a transfer layer 11. In the present embodiment, the raw material composition must contain a photocurable resin composition, and it is not necessary to contain inorganic particles.

<Concave shape forming step>

In this step, as shown in FIGS. 4(b) to 4(c), the transfer layer 11 is irradiated with the active energy ray 17 in a state where the mold 13 is pressed against the transfer layer 11, so that the transfer is performed. The layer 11 is cured to form a resin layer 7 having a concavo-convex shape 4. In the present embodiment, the uneven shape 4 has a shape in which a plurality of holes 3 and a plurality of protrusions 7b are formed on the base surface 7, and the mold 13 is provided with a reverse pattern 15 corresponding to the plurality of holes 3 and the plurality of protrusions 7b. A secondary uneven shape is formed on the base surface 7a by a plurality of protrusions 7b.

<Inorganic film formation and fluorine layer formation step>

In this step, as shown in FIGS. 4(d) to 4(e), the inorganic film 8a is formed so as to cover the resin layer 7 to cover the inorganic film by reacting the inorganic film 8a with a fluorine-containing decane coupling agent. The fluorine-containing layer 9 is formed in the manner of 8a, and the production of the water-repellent member 1 of the present embodiment is completed. The inorganic film 8a is composed of the same inorganic material as the inorganic particles 8, and can be formed by a method such as vapor deposition or sputtering.

This embodiment can also be implemented in the following manner.

In the above embodiment, the projections 7b are formed on the base surface 7a using the mold 13, but the projections 7b may be formed on the base surface 7a by other methods such as sand blasting.

[Examples]

Examples and comparative examples of the present invention are shown below.

<Preparation of UV Curable Resin>

First, a UV curable resin was prepared by mixing a polyfunctional monomer and a photoinitiator in the proportions shown below.

Multifunctional acrylate monomer

Photoinitiator

IRGACURE 184 (manufactured by Ciba Specialty Chemicals) 5 parts by mass

<Example ‧Comparative Example> [Example 1]

To the UV-curable resin prepared above, a nano-sized cerium dioxide toluene dispersion (D50: 150 nm) manufactured by CIK Nanotech Co., Ltd. in a mass ratio of 15% was added, and the mixture was stirred and mixed to obtain a UV-curable resin containing inorganic particles.

Next, the UV curable resin containing the inorganic particles prepared above was applied to the PET substrate by a bar coater so as to have a thickness of 5 μm to form a transfer layer, and after drying at 60 ° C for 5 minutes, The nano-column mold (height 250 nm, period 450 nm, diameter 230 nm) was laminated with a roll from the top in such a manner as to be transferred and laminated on a mold. Thereafter, UV irradiation was performed from the PET substrate side at a cumulative light amount of 500 mJ/cm ² to cure the UV curable resin. Thereafter, the mold was removed, and a transfer product having a primary uneven shape having a plurality of holes provided on the base surface was produced.

Next, using the Plasma Cleaners (PC-300) manufactured by Samco, the transfer product was subjected to an oxygen plasma ashing treatment for 60 seconds under conditions of 200 W and high frequency (13.56 MHz) under a vacuum of 50 [Pa] or less. The inorganic particles are protruded from the base surface of the resin layer, and a secondary uneven shape is formed on the base surface of the resin layer.

Next, OPTOOL DSX manufactured by Daikin Industries Co., Ltd. was applied to the surface of the secondary uneven shape, and reacted at a temperature of 60 ° C and a humidity of 90% for 24 hours to fluorinate the surface of the secondary uneven shape. A water-repellent film formed with a fluorine-containing layer was formed.

[Embodiment 2]

A water repellent film was produced in the same manner as in Example 1 except that a nano column mold (having a height of 220 nm, a period of 240 nm, and a diameter of 140 nm) was used.

[Example 3]

A water repellent film was produced in the same manner as in Example 1 except that a microcolumn mold (height 1700 nm, cycle 3000 nm, diameter 1700 nm) was used.

[Example 4]

For the inorganic particles, an alumina dispersion liquid ALMIBK15 WT%-M21 (D50: 35 nm) manufactured by CIK Nanotech Co., Ltd. in a mass ratio of 5% in terms of solid content was added instead of the nano cerium oxide toluene dispersion, and the examples were 2 A waterproof film was produced in the same manner.

[Comparative Example 1]

A water-repellent film was produced in the same manner as in Example 1 except that the fluorination treatment was not carried out.

[Comparative Example 2]

A water-repellent film was produced in the same manner as in Example 1 except that a nano-column mold (200 nm in depth, 450 nm in cycle, and 230 nm in diameter) was used.

[Comparative Example 3]

The transfer layer was cured by pressing a flat separator instead of the mold on the transfer layer, and the same manner as in Example 1 was carried out except that the oxygen plasma ashing treatment and the fluorination treatment were not performed. Waterproof film.

[Comparative Example 4]

A water-repellent film was produced in the same manner as in Example 1 except that the transfer layer was cured in a state where the flat separator was pressed against the transfer layer.

[Comparative Example 5]

A water-repellent film was produced in the same manner as in Example 1 except that the oxygen plasma ashing treatment and the fluorination treatment were not carried out.

[Comparative Example 6]

A water-repellent film was produced in the same manner as in Example 1 except that a UV-curable resin containing no inorganic particles was formed to form a transfer layer.

<Average height measurement>

According to the observation obtained by scanning probe microscope (L-trace, manufactured by SII NanoTechnology Co., Ltd.), in the cross-sectional profile of a plurality of holes or columns measured by using the scanning probe microscope PC software "SPIWin", The average of the heights of the 5 points adjacent to each other was randomly extracted, and this was taken as the average height of the primary uneven shape.

In the cross-sectional profile when a plurality of holes or columns are not passed, the average of the heights of the five points adjacent to each other is randomly extracted, and this is taken as the average height of the secondary uneven shape.

<Measurement of water contact angle>

For the obtained water-repellent film, 0.5 μl of ion exchange was dropped on the surface of the film at room temperature (25 ° C), and the angle at which the film was in contact with water was measured using a contact angle measuring device (made by Data Physics, OCA 20) (water) Contact angle).

<resistance to scratch resistance test>

The kimwipes paper towel was wiped back and forth 10 times on the surface of the resin layer of the water-repellent film using a friction tester (Rubbing tester IMC-150B, manufactured by Iwahisa Seisakusho Co., Ltd.), and the water contact angle before and after wiping was measured, and the rate of change was calculated. Calculated by the following formula.

Rate of change (%) = (water contact angle before scratching - water contact angle after abrasion) × 100 / (water contact angle before scratch)

Table 1 shows the conditions and measurement results of the examples and comparative examples.

As shown in Table 1, in Examples 1 to 4, the water contact angle before scratching was large, and it was found that the water repellency was excellent. Further, in Examples 1 to 4, since the rate of change in the water contact angle before and after the abrasion was small, it was found that the scratch resistance was excellent. In Example 4, by changing the inorganic particles to alumina, the rate of change in the water contact angle before and after the scratch test was further reduced, and it was found that the scratch resistance was improved.

In addition, as shown in the SEM image of Fig. 5 (a), it was confirmed that the water repellent film of Example 1 had a secondary uneven shape formed by disposing a plurality of inorganic particles on the base surface of the resin layer. In the SEM image of FIG. 5(b), inorganic particles were not observed due to the magnification relationship, but it was confirmed that a secondary uneven shape was formed on the base surface of the resin layer.

1‧‧‧Waterproof parts

3‧‧‧ hole

6‧‧‧Substrate

7‧‧‧ resin layer

7a‧‧‧ base

8‧‧‧Inorganic particles

9‧‧‧Fluorin layer

Claims (9)

A water repellent member having a substrate and a resin layer on at least one side of the substrate, the resin layer having a primary concavo-convex shape in which a plurality of concave portions are provided on a base surface, the concave portion being at the base The area ratio on the surface is 10 to 60%, and a secondary uneven shape is provided on the base surface, and an average height of the secondary uneven shape is 15 nm or more, and fluorine is provided on the surface of the secondary uneven shape. Group. The water-repellent member according to claim 1, wherein the fluorine-containing group is provided on the surface of the secondary uneven shape via an inorganic substance. The waterproof member according to claim 1 or 2, wherein the concave portion is a hole provided in an island shape. The water repellent member according to claim 3, wherein a cross-sectional area of the hole on the base surface is 400 π nm ² to 3600 π μm ² . The waterproof member according to claim 3 or 4, wherein the hole is cylindrical. The water repellent member according to any one of claims 1 to 5, wherein the fluorine-containing group is a perfluoroalkyl group. The water-repellent member according to any one of claims 1 to 6, wherein the contact angle with respect to water is 160 degrees or more. A method for producing a water-repellent member, comprising the steps of: coating a raw material composition obtained by mixing a photocurable resin composition and inorganic particles on a substrate to form a transferred layer; and pressing the mold at the same a state in which the transfer layer is irradiated with an active energy ray to cure the transfer layer to form a resin layer having a concavo-convex shape, and the resin layer is etched to form the resin layer. a step of exposing the inorganic particles to the surface; and a step of forming the fluorine-containing layer in such a manner as to cover the inorganic particles by reacting the inorganic particles with a fluorine-containing decane coupling agent. The method for producing a water repellent member according to claim 8, wherein the inorganic particles have an average particle diameter D50 of 5 to 400 nm.