JPH04359031A - Water- and oil-repellent film and its manufacturing method - Google Patents

Abstract

PURPOSE:To provide a thin water-and-oil repellent film having excellent durability by forming a chemically adsorbed fluorine-containing single molecular membrane on the surface of a surface-roughened film via siloxane bonds. CONSTITUTION:A film 1 of a polyester, trifluorochloroethylene polymer, etc., is subjected to a surface-roughening treatment, brought into contact with a non-aqueous solvent containing a substance having a fluorocarbon group and a chlorosilane group and subsequently washed with a non-aqueous solvent to form a single molecular membrane 2 having an excellent water-and-oil repellence on the film. Since the chemically adsorbed fluorine-containing single molecular membrane 2 is chemically bonded (covalent bonds) to the film substrate via siloxane bonds, the thin water-and-oil repellent film having excellent durability can be formed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water- and oil-repellent film. For more details, please refer to the sandblasting method, molding method,
The present invention relates to a water- and oil-repellent film in which a fluorocarbon water- and oil-repellent monomolecular film is formed on a surface that has been roughened using an etching method.

0002

BACKGROUND OF THE INVENTION Water- and oil-repellent films are useful for pasting on glass windows of high-rise buildings and vehicles, and as cover films for the surfaces of electrical appliances, automobiles, industrial equipment, etc.

Conventionally, methods for producing coating films that have been widely used for the purpose of water and oil repellency generally involve coating Al(
After roughening the surface of the aluminum (aluminum) substrate etc. with a wire brush or chemical etching, etc., and applying a primer etc.,
After applying a paint made by suspending fluorocarbon fine powder such as polytetrafluoroethylene in ethanol, etc. and drying it, approximately 400%
A method has been used in which a fluorocarbon polymer is baked onto the surface of a substrate by heat treatment at a temperature of about .degree. C. for about one hour.

0004

[Problems to be Solved by the Invention] However, although the above-mentioned prior art is easy to manufacture, there is a limit to the adhesion with the base because the polymer and the base are simply bonded by an anchor effect. Furthermore, since the surface of the coating film was subjected to high-temperature heat treatment at about 400° C., the surface was flattened and a good water- and oil-repellent surface could not be obtained. Furthermore, it was impossible to coat plastic films and the like. Therefore, it has been unsatisfactory as a method for manufacturing equipment that requires a water- and oil-repellent coating film, such as pasting on glass windows of high-rise buildings or vehicles, or electrical appliances, automobiles, and industrial equipment. Another method is to apply a fluorocarbon polymer paint, but since the polymer and substrate are only bonded by an anchor effect,
There was a limit to the adhesion to the substrate.

[0005] In order to solve the problems of the prior art, the present invention provides a film that has good adhesion to the surface and has no pinholes.
An object of the present invention is to provide a water- and oil-repellent film having a coating film having excellent water- and oil-repellency, and also excellent heat resistance, weather resistance, and abrasion resistance.

[0006]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the water- and oil-repellent film of the present invention is a film whose surface has been roughened to make it uneven, and has a chemically adsorbed monomolecular film containing fluorine on the surface. is formed through a siloxane bond.

[0007] In the above structure, it is preferable that the roughness of the roughness of the roughened film surface is 0.3 microns or less. Further, in the above configuration, it is preferable that the material of the film is polyethylene terephthalate resin or trifluorochlorinated polyethylene resin.

Furthermore, in the above structure, it is preferable that an adhesive material is applied to the back surface of the film.

[0009]

[Function] According to the structure of the present invention, the surface of the film is roughened, and a chemically adsorbed monomolecular film containing fluorine is formed on the surface of the film through siloxane bonds. It is possible to obtain a water- and oil-repellent film that has good adhesion and no pinholes, and has a coating film that is a fluorine-based coating film and has excellent water and oil repellency, as well as excellent heat resistance, weather resistance, and abrasion resistance. can.

[0010] Furthermore, according to a preferred configuration of the present invention in which the roughness of the roughness of the roughened film surface is 0.3 microns or less, the film has excellent light transmittance, and light transmission in the visible light range of the film is improved. It does not interfere with the characteristics.

[0011] Further, according to a preferred configuration of the present invention in which the material of the film is polyethylene terephthalate resin or trifluorochlorinated polyethylene resin, it is possible to exhibit desirable quality characteristics as a cover film or a protective film.

Furthermore, according to a preferred configuration of the present invention in which the back surface of the film is coated with an adhesive material, the film can be easily attached to a substrate to which it is attached.

[0013]

[Example] The base material to which the water- and oil-repellent film of the present invention is attached may be glass such as vehicle window glass, windshield, eyeglass lenses, building window glass, sanitary ware, tableware, flower vases, water tanks, etc. There are many ceramic products such as sashes, doors, metal products such as exterior walls of buildings, and films for furniture and covers. In addition, as a film material,
Examples include fluororesin films such as trifluorochlorinated polyethylene, polyester films such as polyethylene terephthalate, polyimide films, polyamide films such as nylon, polyethylene films, and polypropylene films.

[0014] An example of a fluorocarbon surfactant that can be used in the present invention is CF3 (CF2).
7 (CH2)2 SiCl3, CF3 (CF2
)5 (CH2)2 SiCl3, CF3CH
2 O(CH2)15SiCl3, CF3(CH
2)2Si(CH3)2(CH2)15Si
Cl3,F(CF2)4(CH2)2Si(
CH3 )2 (CH2 )9 SiCl3 , F(C
F2 )8 (CH2 )2 Si(CH3 )2 (
CH2)9 SiCl3, CF3COO(CH2
)15SiCl3, etc., and if a vinylene group or ethynylene group is added or incorporated into the alkyl chain part,
After the monomolecular film is formed, it can be crosslinked by electron beam irradiation of about 5 megarads, so it is possible to further improve the hardness.

In the present invention, the film surface is preliminarily etched into irregularities on the order of submicrons to microns, or roughened by sandblasting or molding, and one end is coated with chlorosilane groups (SiCln X3-n groups, n = 1, 2, 3, X is a functional group) and a chlorosilane surfactant containing a linear fluorocarbon group at one end is chemically adsorbed onto the film surface to form a monomolecular adsorption film. Therefore, a fluorocarbon chemically adsorbed monomolecular film with extremely high water and oil repellent effects can be produced on the surface.

[0016]Following the process of roughening the surface of the film by etching or sandblasting it into roughness on the order of submicron to micron, the film is brought into contact with a non-aqueous solvent mixed with a substance containing a plurality of chlorosilyl groups to form the above-mentioned surface. A step of reacting the hydroxyl groups on the film surface with the chlorosilyl groups of the substance containing a plurality of chlorosilyl groups to precipitate the substance on the film surface, and removing excess chlorosilyl groups remaining on the film using a non-aqueous organic solvent. A step of washing and removing a substance containing a plurality of silanol groups and then reacting it with water to form a monomolecular film of a substance containing a plurality of silanol groups on the film surface; , n=1, 2, 3, X
The process involves chemically adsorbing a chlorosilane surfactant containing a linear fluorocarbon group at one end onto the film surface to form a monomolecularly adsorbed film, resulting in a higher molecular adsorption density. A fluorocarbon chemisorption monolayer can be produced.

[0017] The roughness of the film surface is preferably on the order of submicrons to microns, that is, 0.3 microns or less. There's no hindrance. Even if the surface roughness of the film becomes rougher than 0.3 microns, it does not affect the water and oil repellency, and although the optical properties deteriorate slightly, there is no problem depending on the application. For example, when producing properties similar to a light-shielding film or frosted glass, it is preferable that the roughness of the surface be considerably rough.

[0018] Furthermore, if an adhesive is applied to the back surface of the film, it can be easily attached to the substrate to which it is attached, and the optical properties will not be affected. Note that a release sheet may be provided on the surface of the adhesive material.

A specific example will be explained below. In the following examples, what is simply expressed as % is wt%.
means. Example 1 As shown in Figure 1, the film thickness was 100 to 200 microns (
Prepare a trifluorochlorinated polyethylene film 1 (μm), hold it at 10-1 to 10-2 Pa in a vacuum chamber, and sputter-etch the surface in advance in a plasma atmosphere using RF glow discharge containing oxygen. Processing is performed at a density of 0.15 W/cm2 for 1 to 10 minutes to form irregularities on the surface. At this time, the surface roughness was approximately 0.1 micron, and the film did not devitrify (FIG. 1(a)). In practice, if it is 0.3 microns or less, it is sufficiently smaller than the wavelength of visible light, so devitrification will not occur, and etching conditions may be selected appropriately. next,
Using a non-aqueous solvent containing a substance containing a fluorocarbon group and a chlorosilane group, for example, the following (Chemical formula 1), a solution of Affluid (a fluorine-based solvent manufactured by Asahi Glass) dissolved at a concentration of about 5% was prepared.

[0020]

[Chemical formula 1]

When the surface-roughened film is immersed in the conditioning solution for about one hour, the film has been etched with oxygen plasma and hydroxyl groups (OH) are formed on the surface, so a dehydrochloric acid reaction occurs on the surface, and the film The following (
The bond of chemical formula 2) was generated, and the monomolecular film 2 containing fluorine could be formed along the irregularities in a chemically bonded state.

[0022]

[Case 2]

Note that this monomolecular film did not peel off at all even when a grid test was conducted. Here, FIG. 1(b) is an enlarged schematic diagram of portion A in FIG. 1(a). Further, in this case, since the fluorocarbon groups were formed on the surface in an oriented state, the surface energy was extremely low, and the wetting angle with respect to water was 135 to 145 degrees.

Example 2 For example, a polyethylene terephthalate film 11 is prepared, maintained at 10-1 to 10-2 Pa in a vacuum chamber, and the surface is sputter-etched in advance in a plasma atmosphere using RF glow discharge containing oxygen. Processing is performed for 1 to 5 minutes at a discharge power density of 0.1 W/cm 2 to form irregularities on the surface. At this time, the surface roughness was approximately 0.1 micron, and the film did not devitrify. In practice, if the thickness is 0.3 microns or less, devitrification will not occur, so etching conditions may be selected appropriately. Further, in the case of a film that does not require transparency, even roughening the surface to a depth of several tens of microns was sufficiently effective.

Next, a reagent containing a large number of chlorosilane groups,
For example, SiCl4 (SiHCl3, SiH2 Cl
2, Cl-(SiCl2O)n-SiCl3 (
Afluid (n is an integer)) dissolved at a concentration of about 5%
When the roughened film is immersed in a solution of Asahi Glass's fluorine-based solvent for about an hour, the film is etched with oxygen plasma and hydroxyl groups ( Since it contains OH)12, a dehydrochloric acid reaction occurs on the surface, and the following (Chemical formula 3) is formed on the film surface.
As shown in (Chemical formula 4), molecules are immobilized on the surface via -SiO- bonds.

[0026]

[Chemical 3]

[0027]

[C4]

Thereafter, a non-aqueous solvent such as Afluid (
When the SiCl4 molecules that have not reacted with the film are removed, the SiCl4 molecules that have not reacted with the film are removed, and as shown in Figure 2(b), the following (chemical
) (Chemical formula 6) etc. is obtained in a chemically bonded state.

[0029]

[C5]

[0030]

[C6]

Then, using a non-aqueous solvent mixed with a substance containing a fluorocarbon group and a chlorosilane group, for example, the following (Chemical formula 7), Afluid (a fluorine-based solvent manufactured by Asahi Glass Co., Ltd.) was dissolved at a concentration of about 3%. ) solution was prepared.

[0032]

[C7]

When the film on which the monomolecular film has been formed is immersed in a conditioning solution for about one hour, the film surface contains a large number of hydroxyl groups (OH), so a dehydrochlorination reaction occurs on the surface, and the following (chemical reaction) occurs on the film surface. 8) is generated, and the connection shown in Figure 2
As shown in (c), the monomolecular film 14 containing fluorine was formed in an uneven state in a chemically bonded state. In addition, this film was used in Example 1.
It was possible to form it at a higher density compared to the previous one.

[0034]

[Chemical formula 8]

Note that this monomolecular film did not peel off at all even when a grid test was conducted. Further, in this case, since the fluorocarbon groups were formed on the surface in an oriented state, the surface energy was extremely low, and the wetting angle with respect to water was 140 to 150 degrees.

Furthermore, an attempt was made to apply an adhesive to the back side of the water- and oil-repellent film obtained in this manner and attach it to glass. A transparent glass with extremely high water and oil repellency was obtained. Furthermore, it is hard to get dirty, and even if it gets dirty, it can be easily removed.
Its practicality was extremely high.

As in the above embodiments, the film surface has been roughened by etching in advance on the submicron to micron order or roughened by sandblasting or molding, and a chlorosilane group (SiCln
3-n group, n=1, 2, 3, Since it forms a carbon-based monomolecular adsorption film, it has a high water and oil repellent effect and does not peel off. The roughness of the film surface is on the order of submicrons to microns, and the thickness of the monomolecular film is on the nanometer level, so it has excellent light transparency and does not interfere with the optical properties of the film, making it highly durable. It can be made excellent.

[0038]

[Effects of the Invention] As explained above, according to the present invention, it is possible to create a transparent film having a highly water- and oil-repellent film on the surface, and this film is fixed to the film surface by chemical bonds (covalent bonds). Therefore, it is possible to obtain a water- and oil-repellent film having a coating film that is not damaged or peeled off, has excellent durability, and has excellent heat resistance, weather resistance, and abrasion resistance. In addition, various base material surfaces can be made water and oil repellent very easily by simply applying a super water- and oil-repellent film without directly treating the surface of the base material.

[Brief explanation of drawings]

FIG. 1 (a) is a conceptual cross-sectional view of a trifluorochlorinated polyethylene film before formation of a water- and oil-repellent film, which is a first example of the present invention. (b) is a conceptual cross-sectional diagram showing part A of the film surface (a) enlarged to the molecular level after forming a water- and oil-repellent film on a trifluorochlorinated polyethylene film according to the first embodiment of the present invention.

FIG. 2 (a) is a conceptual cross-sectional view of a polyethylene terephthalate film according to a second embodiment of the present invention, showing the surface of the film before formation of a water- and oil-repellent film, enlarged to the molecular level. (b) It is a cross-sectional conceptual diagram showing the surface of a polyethylene terephthalate film, which is a second embodiment of the present invention, while a water- and oil-repellent film is being formed, enlarged to the molecular level. (c) It is a cross-sectional conceptual diagram showing the surface of the polyethylene terephthalate film according to the second embodiment of the present invention, after forming a water- and oil-repellent film thereon, enlarged to the molecular level.

[Explanation of symbols]

1 Trifluorochlorinated polyethylene film 2 Monomolecular film 11 Polyethylene terephthalate film 12
Siloxane monolayer 13 Monolayer

Claims (4)

[Claims] 1. A water- and oil-repellent film, characterized in that it is a film whose surface has been roughened to have an uneven surface, and a chemically adsorbed monomolecular film containing fluorine is formed on the surface through siloxane bonds. 2. The water- and oil-repellent film according to claim 1, wherein the roughness of the roughness of the roughened film surface is 0.3 microns or less. 3. The water- and oil-repellent film according to claim 1, wherein the material of the film is polyethylene terephthalate resin or trifluorochlorinated polyethylene resin. 4. The water- and oil-repellent film according to claim 1, wherein an adhesive material is coated on the back side of the film.