JP6003731B2 - Water and oil repellent articles - Google Patents

Description

  The present invention relates to a water / oil repellent article having a surface exhibiting water / oil repellency.

In an article having a fine concavo-convex structure on the surface, it is known that the surface exhibits water and oil repellency (lotus effect).
As the water and oil repellent articles, for example, the following are disclosed.
(1) A water and oil repellent and antifouling film comprising a transparent alumina film having petal-like irregularities formed on a substrate and a water repellent film covering the transparent alumina film (Patent Document 1).
(2) Concave and convex structure formed by photolithography and isotropic wet etching on a substrate (a structure in which a plurality of protrusions are regularly arranged, and a plurality of line protrusions are parallel to each other) A water-repellent structure having a structure disposed on the surface or a structure in which lattice-shaped convex portions are disposed (Patent Document 2).

JP-A-9-202650 JP 2000-203035 A

However, the petal-like irregularities in the water- and oil-repellent and antifouling film of (1), and the projecting projections and line-like projections in the water-repellent structure of (2) are easy to break due to contact, etc. Insufficient sex. Therefore, the water and oil repellency cannot be maintained for a long time. Further, the water repellency is sufficient, but the oil easily enters between the convex portions, and the oil repellency is insufficient.
Although the grid-like convex portions in the water-repellent structure (2) have good wear resistance, the water- and oil-repellency may be insufficient depending on the width and pitch of the grid.

  An object of the present invention is to provide a water- and oil-repellent article having good wear resistance and water- and oil-repellency and capable of maintaining the water- and oil-repellency for a long period of time.

The present invention provides a water / oil repellent article having the following constitutions [1] to [ 4 ].
[1] has a plurality of recesses independent on the surface, the width A of the following recess at half of the position of the depth D of the concave portion, the ratio of the width B of the portion other than below the recess in the same position (A / B) is state, and are 4 to 20, the maximum width C of the recess is a 0.5～150Myuemu, the shape of the recess, wherein the prismatic or cylindrical der Rukoto, repellency Goods.
The width A of the concave portion and the width B of the portion other than the concave portion (convex portion) are the width of the concave portion and the adjacent convexity at a position that is ½ of the depth D of the concave portion for ten concave portions in a vertical cross section at an arbitrary position. The width of each part is measured, and the averaged values are defined as width A and width B, respectively. However, when the concave portion and the convex portion have regularity, the width of the concave portion and the adjacent convex portion at the position of ½ of the depth D of the concave portion in the vertical cross section extending in the direction in which the width B of the convex portion is minimized. The widths of the parts are defined as width A and width B, respectively.
[ 2 ] The water- and oil-repellent article according to [1 ] , wherein the depth D of the recess is 0.2 to 50 μm.
[ 3 ] The water / oil repellent article according to [1] or [ 2], wherein the contact angle of water on the surface having a recess is 90 ° or more, and the contact angle of n-hexadecane on the surface having a recess is 65 ° or more. .
[ 4 ] The water / oil repellent article according to any one of [1] to [ 3 ], having a layer formed of a water / oil repellent agent on a part or all of the surface having a recess.

  The water / oil repellent article of the present invention has good wear resistance and water / oil repellency, and can maintain the water / oil repellency for a long period of time.

1 is a front view showing a first embodiment of a water / oil repellent article of the present invention. It is II-II sectional drawing of FIG. It is sectional drawing which shows 2nd Embodiment of the water / oil repellent article of this invention. It is a front view which shows 3rd Embodiment of the water / oil repellent article of this invention. It is VV sectional drawing of FIG. It is sectional drawing which shows 4th Embodiment of the water / oil repellent article of this invention. It is a front view which shows 5th Embodiment of the water / oil repellent article of this invention.

The following definitions of terms apply throughout this specification and the claims.
A “concave portion” is a space sandwiched between two adjacent convex portions (portions other than the concave portion) in the vertical cross section, and is below the line connecting the highest portions of the two adjacent convex portions at the shortest. Means the space.
The “independent recess” means that when the surface of the article is viewed from the front, the recess is surrounded by the protrusion and adjacent recesses are not continuous.
The “width A of the recessed portion” and the “width B of the portion other than the recessed portion (convex portion)” are the width of the recessed portion at the position of ½ of the depth D of the recessed portion of 10 recessed portions in a vertical cross section at an arbitrary position. Further, the widths of the adjacent convex portions are measured, and the averaged values are defined as width A and width B, respectively.
However, in the case where the concave portion and the convex portion have regularity, in a vertical cross section extending in a direction in which the width B of the convex portion is minimized (for example, the direction perpendicular to the longitudinal direction of the lattice when the convex portion is a lattice shape). The width of the concave portion and the width of the adjacent convex portion at a position of ½ of the depth D of the concave portion are defined as a width A and a width B, respectively.
The “maximum width C of the concave portion” is the length of the longest portion in the horizontal direction in the space constituting the concave portion, and in the vertical section at an arbitrary position, the horizontal direction of the concave portion with respect to ten concave portions The length of the longest part is measured, and a value obtained by averaging the parts is defined as a maximum width C.
“Depression depth D” means a height difference from the deepest part of the concave part to the highest part of the adjacent convex part in the vertical cross section in the definition of width A and width B, and the vertical cross section at an arbitrary position. The height difference from the deepest part of the concave part to the highest part of the adjacent convex part is measured for 10 concave parts, and a value obtained by averaging the difference is defined as depth D.
“Horizontal direction” means a direction parallel to a surface recognized as a surface when the water- and oil-repellent article is viewed macroscopically.
“Water repellency” refers to the property of repelling water.
“Oil repellency” refers to the property of repelling oil.
A “fluoroalkyl group” is a group in which some or all of the hydrogen atoms in the alkyl group are substituted with fluorine atoms, and a “perfluoroalkyl group” is a group in which all of the hydrogen atoms in the alkyl group are substituted with fluorine atoms. It is a group.
The “oxyfluoroalkylene group” is a group in which an etheric oxygen atom and a group in which part or all of the hydrogen atoms of the alkylene group are substituted with a fluorine atom are linked, and the “oxyperfluoroalkylene group” A group in which an etheric oxygen atom and a group in which all of the hydrogen atoms of the alkylene group are substituted with fluorine atoms are linked.

(First embodiment)
FIG. 1 is a front view showing a first embodiment of the water- and oil-repellent article of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG.
The water / oil repellent article 10 has a substrate 12 and a resin layer 14 in contact with the surface of the substrate 12.
On the surface of the resin layer 14, a convex portion 16 whose top portion is continuous in a lattice shape and a plurality of independent rectangular columnar concave portions 18 surrounded by the convex portion 16 are formed.

Examples of the material of the substrate 12 include glass plate, wood, stone, paper, cloth, plastic, silicon, metal and the like. Examples of the shape of the substrate 12 include a film, a plate, and a three-dimensional molded product.
Examples of the material of the resin layer 14 include a cured product of a curable resin, a thermoplastic resin, and the like.

  The ratio (A / B) between the width A of the concave portion 18 at a position of ½ of the depth D of the concave portion 18 and the width B of the convex portion 16 adjacent to the portion other than the concave portion 18 at the same position. 3 or more, and 4 or more is particularly preferable. If (A / B) is large, the region that does not come into contact with water or oil on the surface of the water / oil repellent article 10 becomes wider than the region that comes into contact with water or oil, so that the water / oil repellency is improved. If the width A becomes too large, water or oil tends to enter the concave portion 18, and the width B becomes extremely small and the strength of the convex portion 16 becomes insufficient, so (A / B) is 50 or less is preferable, and 20 or less is particularly preferable.

  The maximum width C of the recess 18 is preferably 0.5 to 150 μm, more preferably 1 to 50 μm, and particularly preferably 3 to 30 μm. If the maximum width C of the concave portion 18 is equal to or more than the lower limit, the region that does not come into contact with water or oil on the surface of the water / oil repellent article 10 is widened, so that the water / oil repellency is improved. If the maximum width C of the recess 18 is less than or equal to the above upper limit, water or oil is unlikely to enter the recess 18.

  The depth D of the recess 18 is preferably 0.2 to 50 μm, particularly preferably 3 to 30 μm. As shown in FIG. 2, the droplet L (water or oil) that contacts the surface of the water / oil repellent article 10 enters the upper portion of the concave portion 18, but due to the balance between the surface tension and the pressure inside the concave portion, It stays at the top. If the depth D of the concave portion 18 is equal to or greater than the lower limit, the droplet L at the top of the concave portion 18 does not contact the bottom of the concave portion 18 and the droplet L does not completely enter the concave portion 18. If the depth D of the recessed part 18 is below the said upper limit, the recessed part 18 will be easy to form.

  The contact angle of water on the surface having the recesses 18 of the water / oil repellent article 10 is preferably 90 degrees or more, more preferably 110 degrees or more, and particularly preferably 120 degrees or more. If the contact angle of water is at least the lower limit, the water repellency will be good. The larger the contact angle of water, the better. The upper limit is not particularly limited, but the upper limit of the contact angle of water is practically about 170 degrees.

  The contact angle of n-hexadecane on the surface having the recesses 18 of the water / oil repellent article 10 is preferably 65 ° or more, more preferably 80 ° or more, and particularly preferably 100 ° or more. If the contact angle of n-hexadecane is at least the lower limit, the oil repellency will be good. The larger the contact angle of n-hexadecane, the better. The upper limit is not particularly limited, but the upper limit of the contact angle of n-hexadecane is practically about 150 degrees.

Examples of the method for producing the water / oil repellent article 10 include a photolithography method and a photoimprint method.
Specifically, as a photolithography method, a negative-type or positive-type photosensitive resin layer is formed on the surface of the substrate 12, and a photomask having a mask pattern corresponding to the pattern of the convex portions 16 and the concave portions 18 is interposed. And a method of developing the resin layer 14 in which the convex portions 16 and the plurality of concave portions 18 surrounded by the convex portions 16 are formed.
Specifically, as the photoimprinting method, a photocurable resin layer is formed on the surface of the substrate 12, and a mold having an inverted pattern of the convex portions 16 and the concave portions 18 is pressed against the photocurable resin layer. And a method of forming the resin layer 14 in which the convex portions 16 and the plurality of concave portions 18 surrounded by the convex portions 16 are formed.

  As a method for producing the water / oil repellent article 10, the photolithography method is preferable from the viewpoint of miniaturization of the pattern of the convex portions 16 and the concave portions 18, and the optical imprint method is preferable from the viewpoint of productivity. As the photoimprinting method, from the viewpoint of excellent productivity, a photocurable resin layer is continuously formed on the surface of the substrate 12 continuously unwound from the roll, and then the substrate is formed into a roll-shaped mold. A so-called roll-to-roll method is particularly preferred, in which the resin layer 14 having the convex portions 16 and the concave portions 18 is formed by exposure while traveling along the surface.

It is preferable to have a layer formed of a water / oil repellent agent on a part or all of the surface of the water / oil repellent article 10 having the recesses 18. By treating the surface having the recesses 18 with a water / oil repellent, the lotus effect is more easily exhibited and the water / oil repellency is further improved.
Examples of the water / oil repellent include a compound having a group capable of contributing to water / oil repellency and a reactive group, or a reaction product thereof (condensate, polymer, etc.).

  Examples of groups that can contribute to water and oil repellency include fluoroalkyl groups, oxyfluoroalkylene groups, alkyl groups, and silicones.

  As the fluoroalkyl group, a fluoroalkyl group having 6 or less carbon atoms is preferable from the viewpoint of little influence on the environment, and from 6 to 6 carbon atoms from the viewpoint of little influence on the environment and good water and oil repellency. A perfluoroalkyl group is particularly preferred.

The oxyfluoroalkylene group is preferably an oxyperfluoroalkylene group from the viewpoint of good water and oil repellency.
The oxyperfluoroalkylene group can be represented by —OC _k F _2k —. However, k is an integer greater than or equal to 1, the integer of 1-10 is preferable, and the integer of 1-6 is especially preferable.
-OC _k F _2k - _{The, -OCF 2 -, - OCF 2} CF 2 -, - OCF 2 CF 2 CF 2 -, - OCF (CF 3) CF 3 -, - OCF 2 CF 2 CF 2 CF 2 - _{, -OCF 2 CF 2 CF 2 CF} 2 CF 2 -, - OCF 2 CF 2 CF 2 CF 2 CF 2 CF 2 - , and the like.
The water / oil repellent may contain one —OC _k F _2k — in the compound, or may contain two or more. When two or more are included, it is preferably a group represented by A- (OC _k F _2k ) _m- (m is an integer of 2 or more). Note that the types of m (OC _k F _2k ) may be the same or different. However, A is a C1-C6 fluoroalkyl group.
The A, preferably perfluoroalkyl group having 1 to 6 carbon _{atoms, CF 3 -, CF 3 CF} 2 -, CF 3 (CF 2) 2 -, CF 3 (CF 2) 3 -, CF 3 (CF 2) _{4 -, CF 3 (CF 2} ) 5 -, CF 3 CF (CF 3) - , and the like.

  The alkyl group is preferably an alkyl group having 8 or more carbon atoms, more preferably an alkyl group having 16 or more carbon atoms, and particularly preferably an alkyl group having 18 or more carbon atoms, from the viewpoint of good water and oil repellency. In addition, an alkyl group having 30 or less carbon atoms is preferable from the viewpoint of easy availability.

Examples of the reactive group include a hydrolyzable silyl group and a polymerizable reactive group.
The hydrolyzable silyl group is a group that can form a silanol group (Si—OH) by a hydrolysis reaction. As the hydrolyzable silyl group, -SiL _m R _3-m (where L is a hydrolyzable group, R is a hydrogen atom or a monovalent hydrocarbon group, and m is an integer of 1 to 3). .). Examples of L include an alkoxy group, a halogen atom, an acyl group, and an isocyanate group.
Examples of the polymerizable reactive group include an acryloyl group and methacryloyl.

  The group capable of contributing to water and oil repellency and the reactive group are preferably bonded by a single bond or a linking group. The linking group is preferably a group having an amide bond, a urethane bond, an ether bond, alkylene or the like.

  Specific examples of the water / oil repellent include a fluorine-containing silane compound having a fluoroalkyl group and / or an oxyfluoroalkylene group and a hydrolyzable silyl group; a fluoroalkyl group and / or an oxyfluoroalkylene group and an acryloyl group; A fluorine-containing polymer obtained by polymerizing or copolymerizing a fluorine-containing acrylic monomer having methacryloyl; a hydrocarbon-based silane compound having an alkyl group and a hydrolyzable silyl group; an acrylic having an alkyl group and an acryloyl group or methacryloyl Examples thereof include hydrocarbon polymers obtained by polymerizing or copolymerizing monomers; silicone oils such as dimethyl silicone oil, methyl phenyl silicone oil, and methyl hydrogen silicone oil.

Examples of commercially available fluorine-containing silane compounds include Afludo (registered trademark) series manufactured by Asahi Glass Co., Ltd., OPTOOL (registered trademark) series manufactured by Daikin, KY-100, KP-911 manufactured by Shin-Etsu Chemical Co., Ltd., and the like.
Commercially available fluoropolymers include Asahi Guard (registered trademark) series manufactured by Asahi Glass, Unidyne (registered trademark) series manufactured by Daikin, Scotchguard (registered trademark) series manufactured by 3M, and Mega manufactured by DIC. For example, the Fuck (registered trademark) series.
Examples of commercially available hydrocarbon silane compounds include Dry Seal (registered trademark) S manufactured by Toray Dow Corning.
Examples of commercially available hydrocarbon polymers include Neoseed (registered trademark) manufactured by Nikka Chemical Co., Ltd.
Examples of commercially available silicone oils include KF-96 and KF-99 manufactured by Shin-Etsu Chemical Co., Ltd.

As a method of forming a layer formed of a water / oil repellent on the surface of the water / oil repellent article 10, a method of forming a layer by applying a coating liquid on the surface of a substrate and drying it (wet coating method) ), A method of forming a layer by treating the surface of the substrate by dry coating (dry coating method).
As a coating method of the coating liquid in the wet coating method, a known method can be appropriately used. Examples of the coating method include a roll coating method, a casting method, a dip coating method (dipping method), a spin coating method, a water casting method, a die coating method, and a Langmuir / Projet method.
Examples of the dry coating method include vacuum deposition, CVD, sputtering, and the like.
The roll coating method is preferable from the viewpoint of cost, the dip coating method is preferable from the viewpoint of high processing speed, and the vacuum deposition method is preferable from the viewpoint of excellent uniformity of the coating film and the simplicity of the apparatus. The vacuum deposition method can be subdivided into resistance heating method, electron beam heating method, high frequency induction heating method, reactive deposition, molecular beam epitaxy method, hot wall deposition method, ion plating method, cluster ion beam method, etc. Any method can be applied.

The coating solution in the wet coating method preferably contains a solvent in that a uniform coating film can be obtained. As the solvent, perfluoroamines (perfluorotripropylamine, perfluorotributylamine, etc.), perfluoroalkanes (Bertrel XF (manufactured by DuPont), etc.) or hydrofluoroethers (AE-3000 (manufactured by Asahi Glass Co., Ltd.)) are preferred. Hydrofluoroethers are particularly preferable because of their low ozone depletion coefficient.
The coating liquid may be any of a solution, a suspension or an emulsion, and a solution is preferable.
The concentration of the water / oil repellent in the coating liquid is preferably 0.001 to 5% by mass, and particularly preferably 0.01 to 1% by mass.
The heating time in the wet coating method is preferably 0.1 to 1 hour.
The heating temperature in the wet coating method is usually 20 to 150 ° C, preferably 80 to 120 ° C.
As the dip coating method, specifically, the water / oil repellent article 10 is immersed in a treatment solution obtained by diluting a water / oil repellent with a solvent, and the solvent is volatilized by drying, followed by heating and water repellent. A method of fixing the oil repellent agent on the surface of the water / oil repellent article 10 may be mentioned.

Examples of the vacuum deposition method include a method in which the water / oil repellent article 10 is placed in a vacuum oven, and the water / oil repellent is heated and evaporated to be fixed on the surface of the water / oil repellent article 10.
The vacuum before vapor deposition is preferably 1 × 10 ⁻³ Pa or less, particularly preferably 1 × 10 ⁻⁴ Pa or less.
The heating temperature of the vapor deposition source does not cause detachment of atoms (fluorine atoms, etc.) constituting the water / oil repellent or cleavage of the water / oil repellent molecular chain (fluorine polymer main chain, etc.). There is no particular limitation as long as the water / oil repellent vapor deposition source has a sufficient vapor pressure. Specifically, 100 to 400 ° C is preferable, 150 to 300 ° C is more preferable, and 200 to 250 ° C is particularly preferable.

(Second Embodiment)
The water / oil repellent article may not have a resin layer and may have a recess on the surface of the substrate.
FIG. 3 is a cross-sectional view showing a second embodiment of the water / oil repellent article of the present invention.
In the water / oil repellent article 10, a convex portion 16 whose top portion is continuous in a lattice shape and a plurality of independent rectangular columnar concave portions 18 surrounded by the convex portion 16 are formed on the surface of the substrate 12.
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 and 2 and description thereof is omitted.

  Examples of the method for producing the water / oil repellent article 10 include a combination of a photolithography method and a dry etching method (plasma etching method or the like) or a wet etching method.

(Third embodiment)
FIG. 4 is a front view showing a third embodiment of the water- and oil-repellent article of the present invention, and FIG. 5 is a cross-sectional view taken along line VV of FIG.
The water / oil repellent article 10 has a substrate 12 and a resin layer 14 in contact with the surface of the substrate 12.
On the surface of the resin layer 14, a convex portion 16 whose top portion is continuous in a lattice shape and a plurality of independent cylindrical concave portions 18 surrounded by the convex portions 16 are formed.
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 and 2 and description thereof is omitted.

(Fourth embodiment)
FIG. 6 is a cross-sectional view showing a fourth embodiment of the water / oil repellent article of the present invention.
The water / oil repellent article 10 has a substrate 12 and a resin layer 14 in contact with the surface of the substrate 12.
On the surface of the resin layer 14, a convex portion 16 having a curved top wall (ridge line portion) and a curved side wall, and a plurality of independent mortar-shaped concave portions 18 surrounded by the convex portions 16 are formed. ing.
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 and 2 and description thereof is omitted.

(Fifth embodiment)
FIG. 7 is a front view showing a fifth embodiment of the water- and oil-repellent article of the present invention.
The water / oil repellent article 10 has a base material (not shown) and a resin layer 14 in contact with the surface of the base material.
On the surface of the resin layer 14, a convex portion 16 whose top portion is continuous in a lattice shape and a plurality of independent hexagonal column-shaped concave portions 18 surrounded by the convex portions 16 are formed.
In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 and 2 and description thereof is omitted.

(Other embodiments)
The water / oil repellent article of the present invention is not limited to the illustrated example, and any article having a plurality of independent recesses on the surface and having (A / B) of 3 or more may be used.

  For example, you may have another layer between a resin layer and a base material. Alternatively, a peelable base material (release paper or the like) may be used as the base material 12, and the resin layer 14 may be separated from the base material 12 to provide a water / oil repellent article composed of only the resin layer 14. From the point that it is easy to form a recess and is excellent in the productivity of the water / oil repellent article, the substrate 12 and the resin layer 14 in contact with the surface of the substrate 12 are provided, and the recess 18 is formed on the surface of the resin layer 14 The water / oil repellent article 10 which is made is preferable.

  The shape of the recess is not limited to the quadrangular prism shape, columnar shape, mortar shape, or hexagonal column shape in the illustrated example, but a triangular prism shape, a pentagonal prism shape, a polygonal prism shape of heptagon or more, a pyramid shape, a conical shape, a truncated pyramid shape, a frustum shape The shape may be a shape, a semicircle, a bell shape, or the like. When the side wall of the convex portion surrounding the concave portion is inclined, as shown in FIG. 6, the droplet L (water or oil) that has entered the upper portion of the concave portion 18 easily comes into contact with the side wall. Since there is a possibility of entering the bottom of the recess 18 while following the side wall, the shape of the recess is preferably a prismatic shape or a columnar shape in which the side wall of the projection surrounding the recess is vertical. In the prismatic shape, a hexagonal prism shape is particularly preferable in that the area of the convex portion can be made smaller than the area of the concave portion, and the manufacturing is easy.

Examples of the method for producing the water / oil repellent article include a thermal imprint method and a laser processing method in addition to the photolithography method, the photoimprint method, the dry etching method and the wet etching method described above.
The surface of the water- and oil-repellent article having a concave portion may have a layer formed from a water- and oil-repellent agent on a part or all of it, and may not have a layer formed from a water- and oil-repellent agent. Also good. By having a layer formed from a water / oil repellent on the surface having a recess, the water / oil repellency is remarkably excellent. However, even if the surface having a recess is not formed from a layer formed from a water / oil repellent, Water and oil repellency can be expressed. In addition, even when the surface having the recesses was treated with a hydrocarbon-based water- and oil-repellent that is inferior to that of a fluorine-based water- and oil-repellent, the smooth surface was treated with the fluorine-based water and oil-repellent. The same level of water and oil repellency can be achieved.

(Function and effect)
Since the water- and oil-repellent article of the present invention described above has a plurality of independent recesses on the surface, the tops (ridges) of the portions (projections) other than the recesses surrounding the recesses are reticulated (for example, lattices). Continuous). For this reason, the strength of the convex portion is higher than that of an independent protruding convex portion, and it is difficult to break due to contact or the like, and as a result, the wear resistance is improved.
Further, since the recesses are independent, when water or oil rides on the recesses, there is no escape space for air existing in the independent recesses, and it is difficult for water or oil to enter the recesses. Therefore, the convex portion that is continuous in a net shape has a wider area in contact with water and oil than an independent protruding convex portion, and although the convex portion is easily wetted by water or oil, water or oil is not contained in the concave portion surrounded by the convex portion. Since it is difficult for oil to enter, it can exhibit water and oil repellency. In addition, when the recesses are independent, the oil repellency is improved as compared with the independent protrusions. That is, in the case of an independent protruding convex portion, since the concave portion is continuous, there is an air escape path existing in the concave portion. For this reason, oil easily enters the recesses between the independent projections, and the oil repellency becomes insufficient.
Further, in the water / oil repellent article of the present invention, the ratio between the width A of the concave portion at the position of ½ of the depth D of the concave portion and the width B of the portion other than the concave portion (convex portion) at the same position. Since (A / B) is 3 or more, the water and oil repellency is good. That is, according to the present invention, a region that is in contact with water or oil is wider than an independent protruding convex portion, and the convex portion that is continuous in a net shape (for example, a lattice shape) may be insufficient in water and oil repellency. Even when it has, it has found out the conditions that can exhibit good water and oil repellency.
In the water / oil / oil repellency article of the present invention, the water / oil repellency can be maintained for a long time because the wear resistance and the water / oil repellency are good.

Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.
Example 1 is a reference example, Examples 3-9 and 13-15 are examples, and Examples 2 and 10-12 are comparative examples.

(Size of concave and convex parts)
The sizes of the concave and convex portions in the scanning electron microscope image of the vertical cross section of the water / oil repellent article were measured.

(Water contact angle)
According to JIS R 3257: 1999 edition “Test method for wettability of substrate glass surface”, water droplets were allowed to stand at five locations on the surface of the article, and the contact angle of water was measured for each water droplet by the sessile drop method. The water droplet was about 2 μL / droplet, and the measurement was performed at 20 ° C. The contact angle of water is shown as an average value of the measured values at five locations.

(Contact angle of n-hexadecane)
In accordance with JIS R 3257: 1999 edition “Method for testing wettability of substrate glass surface”, n-hexadecane droplets were allowed to stand at five locations on the surface of the article, and each droplet was subjected to n-hexadecane by the sessile drop method. The contact angle of was measured. The droplet was about 2 μL / droplet, and the measurement was performed at 20 ° C. The contact angle of n-hexadecane is shown as an average value of measured values at five locations.

(Abrasion resistance)
In accordance with JIS L 0849: 2004 edition, a reciprocating traverse tester (manufactured by KT Corporation) is used, a cellulose non-woven fabric (manufactured by Asahi Kasei Co., Ltd., product name: Bencott M-3) is placed on the surface of the article, and a load of 1 kg is 10 After reciprocating 10,000 times, the contact angle of water was measured and evaluated according to the following criteria.
○ (Good): The contact angle of water is 120 degrees or more and the contact angle of n-hexadecane is 100 degrees or more.
Δ (possible): The contact angle of water is 90 ° or more and less than 120 °, and the contact angle of n-hexadecane is 65 ° or more and less than 100 °.
X (impossible): The contact angle of water is less than 90 degrees or the contact angle of n-hexadecane is less than 65 degrees.

(Water and oil repellent)
Water / oil repellent (1): a fluorine-containing silane compound having an oxyperfluoroalkylene group and a hydrolyzable silyl group, manufactured by Daikin, Optool DSX.
Water / oil repellent (2): CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ SiCl ₃ , CAS NO. 78560-45-9.
Water / oil repellent (3): CH ₃ (CH ₂ ) ₁₄ Si (OCH ₃ ) ₃ , CAS NO. 3069-21-4.

(Example 1)
A silicon wafer (a disk with a diameter of 10.2 mm, a thickness of 100 μm) was prepared as a base material.
The contact angle of water before and after the treatment with the water / oil repellent agent and the contact angle of n-hexadecane on the surface of the base material treated with the water / oil repellent agent (1) by vacuum deposition without forming concaves and convexes. Was measured and the wear resistance was evaluated. The results are shown in Table 1.

(Example 2)
A negative photosensitive resin (trade name: OMR85, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied to the surface of the base material of Example 1 to form a photosensitive resin coating film having a thickness of about 2 μm. Next, the coating film was exposed to light through a photomask having a lattice-like light transmission portion, and subsequently developed to form a photosensitive resin layer as a mask for isotropic plasma etching. Next, isotropic plasma etching using CF ₄ gas was performed, and the photosensitive resin layer was removed with hot sulfuric acid to form a base material on which lattice-shaped convex portions and a plurality of concave portions surrounded by the lattice-shaped convex portions were formed. (The same method as Embodiment 5 described in JP 2000-203035 A). A layer formed of the water / oil repellent (1) was formed on the surface of the substrate having a recess by a vacuum vapor deposition method to obtain a water / oil repellent article. About the surface of the base material which has a recessed part, the size of a recessed part and a convex part, the contact angle of water before and behind a water / oil repellent treatment, and the contact angle of n-hexadecane were measured, and abrasion resistance was evaluated. The results are shown in Table 1.

(Examples 3 to 6)
Except for changing to a photomask having a different lattice spacing, a substrate having a recess having a maximum width C different from that of Example 2 is formed in the same manner as in Example 2, and water repellent is formed on the surface of the substrate having the recess. A layer formed from an oil repellent was formed to obtain a water / oil repellent article. About the surface of the base material which has a recessed part, the size of a recessed part and a convex part, the contact angle of water before and behind a water / oil repellent treatment, and the contact angle of n-hexadecane were measured, and abrasion resistance was evaluated. The results are shown in Table 1.

(Examples 7 to 9)
Except for changing the etching time, in the same manner as in Example 5, a base material having a concave portion having a depth D different from that of Example 5 was formed, and a water- and oil-repellent agent was applied to the surface of the base material having the concave portion. A formed layer was formed to obtain a water / oil repellent article. About the surface of the base material which has a recessed part, the size of a recessed part and a convex part, the contact angle of water before and behind a water / oil repellent treatment, and the contact angle of n-hexadecane were measured, and abrasion resistance was evaluated. The results are shown in Table 1.

(Examples 10 to 12)
A plurality of cylindrical convex portions in the same manner as in Example 2 except that a plurality of circles (diameter 5 μm) are changed to photomasks having light transmission portions arranged with a gap of 20 μm in the vertical and horizontal directions. Was formed, and a layer formed of a water / oil repellent was formed on the surface of the substrate having convex portions to obtain a water / oil repellent article. About the surface of the base material which has a convex part, the size of the convex part, the contact angle of water before and after the water and oil repellent treatment, and the contact angle of n-hexadecane were measured to evaluate the wear resistance. The results are shown in Table 1. However, A is the minimum distance between adjacent convex parts, and C is the maximum distance between adjacent convex parts.

(Examples 13 to 14)
A water / oil repellent article was obtained in the same manner as in Example 8 except that the water / oil repellent (1) was changed to the water / oil repellent (2) or (3). About the surface of the base material which has a recessed part, the size of a recessed part and a convex part, the contact angle of water before and behind a water / oil repellent treatment, and the contact angle of n-hexadecane were measured, and abrasion resistance was evaluated. The results are shown in Table 1.

(Example 15)
A water / oil repellent article was obtained in the same manner as in Example 2 except that the photomask was changed to a hexagonal photomask having a different lattice shape. About the surface of the base material which has a recessed part, the size of a recessed part and a convex part, the contact angle of water before and behind a water / oil repellent treatment, and the contact angle of n-hexadecane were measured, and abrasion resistance was evaluated. The results are shown in Table 1.

In the articles of Examples 3 to 9 and 13 to 15 using the base material having A / B of 3 or more, the contact angle of water was 90 degrees or more, and the contact angle of n-hexadecane was 65 degrees or more. The contact angle of n-hexadecane of the article of Example 1 having a layer formed from a fluorine-based water and oil repellent on the smooth surface of the substrate was higher.
The articles of Examples 2 and 10-12 in which A / B was less than 3 had a contact angle of n-hexadecane of less than 65 degrees.

  The water- and oil-repellent articles of the present invention include various vehicles (vehicles, ships, aircraft, etc.) or architectural glass (internal / external window glass, mirror glass, decorative glass, etc.), building materials, building materials, packaging materials, clothing. Useful as such.

DESCRIPTION OF SYMBOLS 10 Water / oil repellent article 12 Base material 14 Resin layer 16 Convex part 18 Concave part A Concave part width B Width of part other than the concave part (convex part) C Maximum width of the concave part D Concave part depth L Droplet

Claims (4)

Having a plurality of independent recesses on the surface;
The width A of the following recess at half of the position of the depth D of the concave portion, the ratio of the width B of the portion other than below the recess in the same position (A / B) is state, and are 4 to 20,
The maximum width C of the recess is 0.5 to 150 μm,
Shape of the recess, wherein the prismatic or cylindrical der Rukoto, repellent article.
The width A of the concave portion and the width B of the portion other than the concave portion (convex portion) are the width of the concave portion and the adjacent convexity at a position that is ½ of the depth D of the concave portion for ten concave portions in a vertical cross section at an arbitrary position. The width of each part is measured, and the averaged values are defined as width A and width B, respectively. However, when the concave portion and the convex portion have regularity, the width of the concave portion and the adjacent convex portion at the position of ½ of the depth D of the concave portion in the vertical cross section extending in the direction in which the width B of the convex portion is minimized. The widths of the parts are defined as width A and width B, respectively. The water / oil repellent article according to claim 1, wherein the depth D of the recess is 0.2 to 50 μm. The water / oil / oil repellent article according to claim 1 or 2 , wherein the contact angle of water on the surface having a recess is 90 ° or more, and the contact angle of n-hexadecane on the surface having a recess is 65 ° or more. The water / oil repellent article according to any one of claims 1 to 3 , further comprising a layer formed of a water / oil repellent on a part or all of the surface having a recess.

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