Solid surface demisting film without external energy input, demisting method and application

Abstract

The invention provides a solid surface demisting film without external energy input, a demisting method and application. The solid surface demisting film without external energy input comprises a super-hydrophobic substrate and a hydrophilic dot matrix located on the surface of one side of the super-hydrophobic substrate. The hydrophilic dot matrix comprises a plurality of hydrophilic dots. The fusion induction droplet jumping phenomenon is utilized, and the size of fused droplets is effectively controlled. No complex microstructure exists, the preparation cost is low, the preparation difficulty is small, the technology is simple, and the application prospect is wide.

Description

Technical Field

[0001] The invention relates to the field of demisting technology, and in particular to a solid surface demisting film that does not require external energy input, a demisting method and an application thereof. Background Art

[0002] Surface fogging is a common phenomenon in people's production and life. The appearance of fog often brings great troubles and even dangers to people. For example, fogging of camera lenses affects shooting, fogging of condenser surfaces turns into water film affecting heat transfer, fogging of solar panels reduces power generation efficiency, fogging of the inside of vehicle windshields endangers traffic safety, the surface of offshore equipment is corroded by condensed water for a long time, and fogging of glasses lenses affects daily life and even endangers personal safety, etc.

[0003] When relatively humid and high temperature air contacts the surface of a low temperature object, gaseous water molecules will condense into small water droplets on the surface. The densely packed small water droplets will cause light to diffusely reflect, resulting in fogging on the surface. There are currently three mainstream surface defogging technologies, all of which can only be regarded as a compromise with "fog":

[0004] A. Heating the surface to evaporate the droplets and prevent gaseous water molecules from re-condensing on the overheated surface; this solution requires external energy input and requires additional components near the surface to complete the heating process, which will cause additional production costs. There is also an obvious and serious problem that it usually takes more than ten seconds or even longer to complete the heating of the droplets and completely evaporate them, which is a major hidden danger in some specific problems, such as: fogging of the front windshield of a car when driving on the highway.

[0005] B. Cover the surface with a super-hydrophilic layer so that the droplets can quickly spread into a liquid film on the surface, reducing diffuse reflection. Although this solution does not require external energy input, the large-area coverage of the super-hydrophilic layer will cause the surface to retain water too strongly. Without external energy participation, the surface will be covered with a water film for a long time. This water film is fluid and will seriously affect vision.

[0006] C. The surface is covered with a super-hydrophobic layer to reduce the adhesion between the droplets and the surface. When the volume of the condensed droplets is too large, they will automatically detach from the surface under the influence of gravity. This solution requires the condensed droplets to be large enough to obtain energy from gravity to detach from the surface. Obviously, the ability to suppress fogging is weak (small droplets cannot be removed). This solution also requires the surface to have an inclination. On a horizontal surface, there is no other energy input, and this solution almost loses the ability to remove droplets.

[0007] Therefore, it is of great significance to provide a solid surface demisting technology that does not require external energy input. Summary of the invention

[0008] The purpose of the present invention is to provide a solid surface demisting film, a demisting method and an application thereof which do not require external energy input, so as to solve the problems existing in the prior art.

[0009] The technical solution adopted to achieve the purpose of the present invention is as follows: a solid surface demisting film that does not require external energy input includes a super hydrophobic substrate and a hydrophilic lattice located on one side of the super hydrophobic substrate. The hydrophilic lattice includes a plurality of hydrophilic points.

[0010] Furthermore, the hydrophilic points are provided by chemical modification or coating technology.

[0011] The present invention also discloses a solid surface demisting method according to the demisting film, wherein the demisting film is covered on the main surface of an object by attaching or adhering. The side of the super hydrophobic substrate having the hydrophilic lattice faces away from the main surface of the object.

[0012] The invention also discloses the application of the method in automobile windshield, camera lens, eyeglass lens, aircraft windshield and solar panel. The defogging film at least covers the light-transmitting area of ​​the automobile windshield, camera lens, eyeglass lens, aircraft windshield and solar panel.

[0013] The present invention also discloses a solid surface demisting method that does not require external energy input, wherein the main surface of the object is modified into a super-hydrophobic main surface, and a hydrophilic lattice is prepared on the super-hydrophobic main surface. The hydrophilic lattice includes a plurality of hydrophilic points.

[0014] Furthermore, the hydrophilic points are set by electrochemical etching, coating technology, or vapor deposition.

[0015] Furthermore, the hydrophilic dot matrix includes a plurality of hydrophilic dot units arranged in a matrix. Each hydrophilic dot unit includes two rows and two columns of four hydrophilic dots arranged equidistantly. The center distance between two adjacent hydrophilic dots in the hydrophilic dot unit is DS. The center distance between two adjacent hydrophilic dot units is D HSU Among them, D S <200 nm. D HSU >2×D S .

[0016] Furthermore, the hydrophilic points are circular or polygonal.

[0017] Furthermore, the hydrophilic points are nanocolumns.

[0018] The invention also discloses application of the method in electronic products, offshore equipment surfaces, low-temperature equipment surfaces, and water collection devices.

[0019] The technical effect of the present invention is unquestionable: the size of the fused droplets is effectively controlled by utilizing the fusion-induced droplet jumping phenomenon; there is no complex microstructure, the preparation cost is low, the preparation difficulty is small, the technology is simple and the application prospects are broad. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the overall schematic diagram of the defogging film;

[0021] Figure 2 Schematic diagram of the hydrophilic point unit spacing;

[0022] Figure 3 Schematic diagram of hydrophilic point unit;

[0023] Figure 4 Schematic diagram of triangular hydrophilic lattice;

[0024] Figure 5 It is a schematic diagram of a rectangular hydrophilic lattice;

[0025] Figure 6 Schematic diagram of the hydrophilic lattice of the composite graphic.

[0026] In the figure: super hydrophobic substrate 1, hydrophilic lattice 2. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0028] Embodiment 1:

[0029] This embodiment discloses a solid surface demisting film that does not require external energy input, including a super-hydrophobic substrate 1 and a hydrophilic dot matrix 2 located on one side of the super-hydrophobic substrate 1. The hydrophilic dot matrix 2 includes a plurality of hydrophilic dots.

[0030] It is worth mentioning that the fusion-induced droplet jumping phenomenon refers to the phenomenon that when two or more droplets come into contact on a surface, the surface tension of the droplets drives them to merge toward the center of mass. When fusion occurs, a liquid bridge will appear between the two (or more) droplets, and the liquid bridge will expand and hit the solid surface, providing the droplets with a force perpendicular to the solid surface, driving the fused droplets to detach from the surface. If the droplet diameter is smaller than the minimum wavelength of visible light, 400 nanometers, when and after the droplets merge, there will be no "atomization phenomenon" on the surface.

[0031] In this embodiment, the super-hydrophobic substrate 1 is provided for several purposes: (1) the nucleation-condensation-growth of water molecules in the hydrophobic part is inhibited; (2) when droplet fusion occurs, the hydrophobic main surface will cause the movement of the droplets to be less constrained, which is beneficial to the entire process of droplet centripetal fusion to jumping off.

[0032] The hydrophilic points are set to act as nucleation seeds, so that water molecules in the air tend to nucleate and condense and grow on the hydrophilic points, making the location where the droplets appear controllable.

[0033] Embodiment 2:

[0034] The main contents of this embodiment are the same as those of Embodiment 1, wherein the hydrophilic points are set by chemical modification or coating technology.

[0035] Embodiment 3:

[0036] This embodiment provides a solid surface demisting method without external energy input according to the demisting film of embodiment 1 or 2, wherein the demisting film is covered on the main surface of the object by attaching or adhering. The side of the super hydrophobic substrate 1 having the hydrophilic lattice 2 faces away from the main surface of the object.

[0037] Embodiment 4:

[0038] This embodiment provides the application of the method described in Example 3 in automobile windshields, camera lenses, eyeglass lenses, aircraft windshields, and solar panels. The defogging film at least covers the light-transmitting area of ​​the automobile windshield, camera lenses, eyeglass lenses, aircraft windshields, and solar panels. Since this embodiment does not manufacture complex microstructures on the surface and can remove droplets smaller than the wavelength of visible light, it is very desirable for such surfaces.

[0039] Embodiment 5:

[0040] This embodiment provides a solid surface demisting method that does not require external energy input, and modifies the main surface of the object into a super-hydrophobic main surface. A hydrophilic dot matrix 2 is prepared on the super-hydrophobic main surface. The hydrophilic dot matrix 2 includes a plurality of hydrophilic dots.

[0041] This embodiment uses the phenomenon of fusion-induced droplet jumping to provide a demisting technology that can effectively control the size of fused droplets, has no complex microstructure, low preparation cost, low preparation difficulty, simple technology, and broad application prospects. This embodiment is at the forefront of related research and is quite innovative.

[0042] Embodiment 6:

[0043] The main contents of this embodiment are the same as those of Embodiment 5, wherein the hydrophilic points are set by electrochemical etching, coating technology, or vapor deposition.

[0044] Embodiment 7:

[0045] The main contents of this embodiment are the same as those of Embodiment 3 or 5, wherein the hydrophilic dot matrix 2 comprises a plurality of hydrophilic dot units arranged in a matrix. Each hydrophilic dot unit comprises four hydrophilic dots arranged in two rows and two columns at equal intervals. Figure 2 and Figure 3 The center distance between two adjacent hydrophilic points in the hydrophilic point unit is D S The center distance between two adjacent hydrophilic point units is D HSU Among them, D S <200 nm. D HSU >2×D S The center distance between the four hydrophilic points in the hydrophilic point unit (D S ) is controllable. For the defogging problem, the center distance of the hydrophilic points should be less than 200 nanometers to ensure that the droplets come into contact with the condensed droplets on the other three hydrophilic points in the unit before growing to a diameter of 400 nanometers. In this way, when and after the droplets merge, the droplet diameter is smaller than the minimum wavelength of visible light, 400 nanometers, thereby preventing surface atomization. For other problems such as preventing the formation of liquid film, the center distance of the hydrophilic points is set as required.

[0046] A large number of hydrophilic point units are set on the hydrophobic main surface. Since the symmetrical fusion of four droplets can enhance the jumping performance of the droplets, the center distance between the hydrophilic point units (D HSU ) can be greater than 2 times D S , making the surface more prone to the fusion of four droplets. This can allow the surface to achieve better droplet jumping performance, in other words, it can make some droplets containing special components that are not easy to jump complete the jump.

[0047] Embodiment 8:

[0048] The main contents of this embodiment are the same as those of embodiment 3 or 5, wherein the hydrophilic points can be in various shapes. In actual production, the hydrophilic points can be circular or polygonal. Figure 1 , Figure 4 and Figure 5 Circular, triangular, and rectangular hydrophilic spots are shown, respectively. Figure 6 A composite patterned hydrophilic dot array is shown. Figure 6 In the hydrophilic unit, the shapes and areas of the two rows of hydrophilic points are inconsistent, and there is a Laplace pressure difference between the droplets, which causes the fused droplets to have a horizontal velocity. The specific application needs to refer to the actual needs of the project. It is worth noting that the attached Figures 4 to 6 The non-solid wireframe on the central main surface is only to indicate the geometry of the hydrophilic point.

[0049] This embodiment does not limit the manner in which the desired surface is set. For example, the surface (or super-hydrophobic surface) can be directly modified by chemical etching, physical / chemical deposition, etc. The pre-prepared demisting film can also be covered on the surface by attaching or adhering, so that the object has anti-fog, anti-corrosion and other properties. The main surface and the hydrophilic point can have a curvature and can be set on a flat plate such as a solar panel, or on a non-planar surface.

[0050] Embodiment 9:

[0051] The main contents of this embodiment are the same as those of embodiment 3 or 5, wherein the hydrophilic dots are nanorods. The hydrophilic dots have a certain thickness. It is worth noting that the thickness of the hydrophilic dots is very small relative to the diameter of the droplet.

[0052] Embodiment 10:

[0053] This embodiment applies the method described in embodiment 3 or 5 to surfaces with corrosion (or antifouling) requirements such as electronic products and marine equipment surfaces. Since the present invention can remove droplets that pose a corrosive threat to the surface, it is desirable for such surfaces.

[0054] Embodiment 11:

[0055] This example applies the method described in Example 3 or 5 to a cryogenic equipment surface. The present invention is desirable for such surfaces because it can remove droplets before they freeze.

[0056] Embodiment 12:

[0057] This embodiment applies the method described in embodiment 3 or 5 to a water collection device. Providing a water collection structure in the direction of the droplet jumping speed can complete water collection, which is desirable for this type of product.

Claims

1. A solid surface demisting film that does not require external energy input, characterized in that: It comprises a super-hydrophobic substrate (1) and a hydrophilic dot matrix (2) located on one surface of the super-hydrophobic substrate (1); the hydrophilic dot matrix (2) comprises a plurality of hydrophilic dots.

2. The solid surface demisting film that does not require external energy input according to claim 1, characterized in that: The hydrophilic points are provided by chemical modification or coating technology.

3. A solid surface demisting method without external energy input according to claim 1, characterized in that: The defogging film is covered on the main surface of the object in a pasting or adhesive manner; the side of the super hydrophobic substrate (1) having the hydrophilic dot matrix (2) faces away from the main surface of the object.

4. Application of the method of claim 3 in automobile windshields, camera lenses, eyeglass lenses, aircraft windshields, and solar panels; the demisting film at least covers the light-transmitting area of ​​the automobile windshields, camera lenses, eyeglass lenses, aircraft windshields, and solar panels.

5. A method for demisting a solid surface without external energy input, characterized in that: The main surface of the object is modified into a super-hydrophobic main surface; a hydrophilic dot matrix (2) is prepared on the super-hydrophobic main surface; the hydrophilic dot matrix (2) includes a plurality of hydrophilic dots.

6. A solid surface demisting method without external energy input according to claim 5, characterized in that: The hydrophilic points are set by electrochemical etching, coating technology, or vapor deposition.

7. A solid surface demisting method without external energy input according to claim 3 or 5, characterized in that: The hydrophilic dot matrix (2) comprises a plurality of hydrophilic dot units arranged in a matrix; each hydrophilic dot unit comprises four hydrophilic dots arranged in two rows and two columns at equal intervals; the center distance between two adjacent hydrophilic dots in the hydrophilic dot unit is D S ; The center distance between two adjacent hydrophilic point units is D HSU ; Among them, D S <200 nm. D HSU >2×D S .

8. A solid surface demisting method without external energy input according to claim 3 or 5, characterized in that: The hydrophilic points are circular or polygonal.

9. A solid surface demisting method without external energy input according to claim 3 or 5, characterized in that: The hydrophilic dots are nanorods.

10. Use of the method according to claim 3 or 5 in electronic products, offshore equipment surfaces, low-temperature equipment surfaces, and water collection devices.

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