Water-slip membrane and article having water-slip membrane on surface

Abstract

The present invention is a water-slip membrane 10 that can maintain fixed drop characteristics or greater even after a weathering test or saline spray test, the water-slip membrane comprising a base layer 14 formed on a glass base material 12, and a lubricating layer 16 held on the base layer 14. The base layer 14 is formed by modifying a reactive functional group on the surface of the glass base material 12, and the lubricating layer 16 is composed of a polymer containing a reactive functional group capable of covalent bonding with the reactive functional group of the base layer 14. A portion of the reactive functional group of the base layer 14 and a portion of the reactive functional group of the lubricating layer 16 are covalently bonded. Furthermore, the base layer 14 contains a cyclic conjugated functional group modified on the surface of the glass base material 12, and the lubricating layer 16 includes a polymer containing hydrogen atoms charged to δ+. A portion of the cyclic conjugated functional group of the base layer 14 and a portion of the hydrogen atoms charged to δ+ of the lubricating layer 16 have π-electron interaction.

Description

Synovial membranes and articles having synovial membranes on their surfaces Related Applications

[0001] This application claims priority to Japanese Patent Application No. 2021-122645, filed on July 27, 2021, which is incorporated herein by reference.

[0002] The present invention relates to a slideable film comprising a base layer and a lubricating layer supported on the base layer, and to an article having a surface coated therewith.

[0003] One idea is to form a film of lubricating liquid on the surface of an article to achieve liquid non-wettability (sliding characteristics).In conventional technology, it was necessary to form a microporous structure on the surface of the article in advance and retain the lubricating liquid in the microporous structure in order to prevent the lubricating liquid from leaking out.

[0004] In contrast, the synovial membrane of Patent Document 1 has the characteristic that the base layer retains lubricating fluid through π-electron interactions, and is attracting attention because it can impart sliding properties to flat surfaces without the need to form a microporous structure on the surface of the article.

[0005] Furthermore, advances in image processing technology have led to the miniaturization of cameras and lenses in recent years, placing increasing importance on the water droplet adhesion characteristics of small-area image capture ports. Conventionally, evaluation of water droplet adhesion characteristics has often been performed solely by visual inspection, using water or liquid droplets of 10 μl or more, which can be easily formed with a dropper. However, it has been found that smaller droplets have a greater impact on visibility. This is because the smaller the droplet, the greater the adhesion force due to slight depressions or stains on the surface.

[0006] In Patent Document 1, the sliding properties are evaluated using water droplets of 10 μl or more, but no evaluation is made for droplets of smaller size. Patent Document 1 also reports that on a superhydrophobic surface (SHS), the movement of a 5 μl droplet is hindered by the surface irregularities, making it difficult for the droplet to slide off. For this reason, the inventors established a method for forming a surface that allows droplets of 4 μl or less (diameter φ = 2 mm or less) to slide off.

[0007] Patent No. 6678018

[0008] While the inventors were working to put the synovial membrane described in Patent Document 1 into practical use, the synovial membrane of Patent Document 1 had a problem in that it could not maintain the ability to drop water droplets of 1 to 2.5 mm in diameter (they did not drop) after a 120-hour weather resistance test or a 240-hour salt spray resistance test.

[0009] The object of the present invention is to provide a slipping film consisting of a base layer formed on a substrate and a lubricating layer supported by the base layer, which maintains a certain level of slippage characteristics even after weather resistance tests and salt spray resistance tests.

[0010] In order to solve the above problems, the inventors conducted extensive research and discovered that by using a base layer in which reactive functional groups have been modified on the surface of a substrate and forming a lubricating layer using a polymer containing reactive functional groups that covalently bond to the reactive functional groups, some of the reactive functional groups in the base layer and some of the reactive functional groups in the lubricating layer become covalently bonded, thereby maintaining a certain level of sliding properties even after weather resistance tests and salt spray resistance tests, and thus completing the present invention.

[0011] That is, the slide film according to the present invention comprises a base layer formed on a substrate and a lubricating layer held by the base layer, wherein the base layer is formed by modifying the surface of the substrate with reactive functional groups, the lubricating layer is made of a polymer containing reactive functional groups capable of covalently bonding with the reactive functional groups of the base layer, and some of the reactive functional groups of the base layer and some of the reactive functional groups of the lubricating layer are covalently bonded, and the base layer contains cyclic conjugated functional groups modified on the surface of the substrate, and the lubricating layer has a molecular weight of δ ＋ a polymer containing a hydrogen atom charged at δ ＋ It is characterized by π electron interactions with some of the positively charged hydrogen atoms.

[0012] Here, the "reactive functional group" is preferably at least one functional group selected from the group consisting of a carbon-carbon double bond-containing group, a carboxy group, an amino group, a hydroxy group, and an epoxy group. Furthermore, "covalently bonded" also includes polymerization reactions, copolymerization reactions, crosslinked structures, graft structures, and the like. Furthermore, the "cyclic conjugated functional group" refers to a functional group having conjugated double bonds in which two or more double bonds are connected via a single bond, particularly one in which the conjugated double bonds form a ring, such as a benzene ring.

[0013] In the present invention, the base layer is preferably a silicon oxide (SiOx) containing the reactive functional group and the cyclic conjugated functional group.

[0014] In the present invention, the lubricating layer is formed by the reactive functional group and the δ ＋ It is preferable that the silicone be a modified silicone containing positively charged hydrogen atoms.

[0015] In the present invention, it is preferable that the reactive functional group of the base layer is at least one functional group selected from the group consisting of a vinyl group, an acrylic group, a methacrylic group, a carboxy group, an amino group, a hydroxy group, and an epoxy group, and that the cyclic conjugated functional group of the base layer is a phenyl group.

[0016] In the present invention, the reactive functional group of the lubricating layer is at least one functional group selected from the group consisting of a carboxy group, a vinyl group, an acrylic group, a methacrylic group, an amino group, a hydroxy group, and an epoxy group, and the δ ＋ Preferably, the positively charged hydrogen atom is part of at least one functional group selected from the group consisting of a carboxy group, a phenol group, and a hydroxy group.

[0017] In the present invention, the mass ratio of the cyclic conjugated functional group component of the base layer to the reactive functional group component of the base layer is preferably 1:1 to 1:3.

[0018] The article according to the present invention is characterized by having a surface covered with the above-mentioned synovial membrane.

[0019] The slide film and article according to the present invention exhibit the following effects. (1) By appropriately adding a covalent bond component due to a reactive functional group and a component exhibiting π-electron interaction to the base layer and lubricating layer, respectively, weather resistance and rolling resistance after a salt spray test are dramatically improved. (2) In particular, durability (roll resistance) is dramatically improved in the salt spray test compared to when covalent bonding and π-electron interaction are used alone. This effect far exceeds the expected effect when the two (covalent bonding and π-electron interaction) are simply combined, and can be said to be an unexpected effect. (3) The weather resistance test involves repeated water spraying and drying while irradiating with UV light. Because covalent bonds are stronger than π-electron interactions, strengthening the covalent bond between the base layer and lubricating layer improves weather resistance. However, covalent bonding alone was unable to improve the deterioration of rolling resistance after a salt spray test. The reason for this is thought to be that in salt spray resistance tests, saltwater with high osmotic pressure gradually penetrates the interface between the base layer and the lubricating layer, weakening the ability of the base layer to hold the lubricating layer.In contrast, when π-electron interactions are used, the lubricating layer is thought to densely coat the base layer, preventing saltwater from penetrating the interface between the base layer and the lubricating layer, resulting in relatively good durability against salt spray.However, because the bond of the π-electron interaction itself is weak, it is extremely weak in weather resistance tests that involve repeated water spraying and drying.In the present invention, by appropriately combining both (covalent bonds and π-electron interactions), it is possible to achieve both a strong bond between the base layer and the lubricating layer and a dense coating by the lubricating layer, and it is thought to have obtained improved effects that could not be achieved by either alone.

[0020] According to the present invention, the cyclic conjugated functional group of the base layer and the δ ＋ In addition to the π electron interaction with positively charged hydrogen atoms, the surface of the substrate is modified with reactive functional groups to form the base layer, and the lubricating layer is formed using a polymer containing reactive functional groups that covalently bond to the reactive functional groups. As a result, some of the reactive functional groups in the base layer and some of the reactive functional groups in the lubricating layer are covalently bonded, and even after weather resistance tests and salt spray resistance tests, the sliding properties of the polymer in the lubricating layer held by the base layer are maintained to a certain level.

[0021] FIG. 1 is a diagram showing a schematic structure of a synovial membrane according to one embodiment of the present invention. FIG. 2 is a diagram for explaining a method for manufacturing the synovial membrane. FIG. 3 is an explanatory diagram for a method for evaluating fall characteristics. FIG. 4 is a graph showing test results for a synovial membrane of Configuration 4 (Comparative Example). FIG. 5 is a graph showing test results for a synovial membrane of Configuration 5 (Comparative Example). FIG. 6 is a graph showing test results for a synovial membrane of Configuration 1 (Example). FIG. 7 is a graph showing test results for a synovial membrane of Configuration 2 (Example). FIG. 8 is a graph showing test results for a synovial membrane of Configuration 3 (Example). FIG. 9 is a graph showing test results for a synovial membrane of Configuration 6 (Comparative Example). FIG. 10 is a graph showing test results for a synovial membrane of Configuration 7 (Comparative Example). FIG. 11 is a graph showing test results for synovial membranes of Configurations 1-1 (Example) and 1-2 (Example).

[0022] 1 shows a schematic diagram of a synovial membrane according to one embodiment of the present invention. In the figure, the synovial membrane 10 comprises a base layer 14 having a carbon-carbon double bond-containing group (vinyl group) and a cyclic conjugated functional group (phenyl group) modified on the surface of a glass substrate 12, and a lubricating layer 16 supported on the base layer 14. The lubricating layer 16 contains a hydrophobic modified silicone oil modified with a reactive functional group (carboxy group) capable of covalent bonding to the vinyl group of the base layer 14, and a δ group capable of π-electron interaction with the phenyl group of the base layer 14. ＋ and a hydrophobic modified silicone oil modified with a functional group (phenol group) having a positively charged hydrogen atom.

[0023] Furthermore, due to the hydrophobic and water-sliding properties of the modified silicone oil, some of which is held by covalent bonds to the vinyl groups of the base layer 14, and some of which is held by π-electron interactions to the phenyl groups of the base layer 14, water droplets on the water-sliding film 10 slide off when the glass substrate 12 is tilted slightly.

[0024] [Base Layer] The base layer 14 of this embodiment preferably has, in addition to a vinyl group and a phenyl group, an anchoring group (e.g., a silane group) that firmly bonds to the surface of the glass substrate 12. The vinyl group may also be an acrylic group or a methacrylic group. The silane group is preferably an alkoxysilane such as tetraethoxysilane (TEOS) or a hydrolysis product thereof, which firmly bonds to the surface of the glass substrate 12 through a covalent bond.

[0025] As the substrate, glass, metal, or the like having polar groups such as hydroxyl groups on the surface can provide good adhesion during hydrolysis of the base layer 14. Therefore, the substrate is not limited to glass substrate 12. In the case of a resin substrate, it is also possible to form polar groups on the surface by subjecting it to plasma treatment.

[0026] The base layer 14 may also contain a π-electron functional group having a high concentration of π electrons, such as a phenyl group (a functional group having a benzene ring) or an alkynyl group (a functional group having a carbon-carbon triple bond). For example, an alkoxysilane containing a phenyl group is preferred as the material for forming the base layer 14. Examples include phenyltriethoxysilane (PTES), phenyltrimethoxysilane, phenylchlorosilane, and phenylmethylchlorosilane. In order to increase the π-electron concentration of the π-electron functional group, for example, a phenyl group-insulating moiety (Ph-SiO ２ The insulating silica structure (SiO ２ It is particularly preferable that the phenyl group contains the movement of π electrons. In addition, an alkoxysilane such as tetraethoxysilane (TEOS) may be mixed to reinforce the fixation to the surface of the glass substrate 12. If these substances are used to form the base layer 14, the phenyl group will have a silica structure (SiO ２ ) and the surface of the glass substrate 12 is modified.

[0027] Other examples of materials that can be used to form the base layer 14 containing a π-electron functional group include aromatic alcohols such as polystyrene, phenethyl alcohol, phenol, phenanthrenol, and cresoltetrahydrophenanthrenol; aromatic aldehydes such as phenylacetaldehyde, methoxybenzaldehyde, cuminaldehyde, and hexylcinnamaldehyde; aromatic carboxylic acids such as phenanthrenecarboxaldehyde, phthalic acid, and benzoic acid; aromatic isocyanates; aromatic thiols such as thiophenol; and phenyl chlorides and anilines.

[0028] Furthermore, as the base layer 14 containing (i) a vinyl group (an acrylic group, a methacrylic group) and (ii) a phenyl group, for example, a mixture of alkoxysilanes in which one of the alkoxides, such as (i) vinyltrimethoxysilane (3-acryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane) or (ii) phenyltriethoxysilane, is substituted with a vinyl group (an acryloxy group, a methacryloxy group) or a phenyl group, can be hydrolyzed and formed into a film on the substrate, thereby forming the base layer 14 containing a vinyl group (an acrylic group, a methacrylic group) and a phenyl group.

[0029] To form the base layer 14 using the above substances, it is preferable to first make the surface of the glass substrate 12 on which the base layer 14 is to be formed solvent-philic to the constituent substances of the base layer 14. Even if it is a poor solvent, it is possible to use an alkali treatment or UV / O ３ The surface of such a glass substrate 12 can be coated by a casting method, a squeegee method, a dipping method, a spin coating method, or the like.

[0030] Furthermore, it is preferable to use an organic solvent when cleaning is performed after forming the base layer 14. Examples of organic solvents for cleaning include toluene, benzene, pentane, hexane, heptane, cyclohexane, methyl chloride, methyl bromide, ethyl acetate, diethyl ether, tetrahydrofuran, ethyl cellosolve, acetone, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, and chloroform.

[0031] [Lubricating Layer] The modified silicone oil constituting the lubricating layer 16 of this embodiment is formed by mixing the various modified silicone oils, applying the mixture to the base layer 14, and then heat treating the mixture (at 300°C or less). The thickness of the lubricating layer 16 can be adjusted by the application conditions or by diluting the mixture with a solvent such as methyl ethyl ketone, toluene, or a mixture thereof.

[0032] As the modified silicone oil, for example, carboxy-modified silicone, phenol-modified silicone, etc. are used, as shown in Figure 1. These modified silicones (manufactured by Shin-Etsu Chemical Co., Ltd.) all have a silicone main chain that is virtually non-volatile at room temperature and exhibits lyophobicity toward the liquid to be slid down, and are modified with functional groups (carboxy, phenol, vinyl, acrylic, methacrylic, amino, hydroxy, epoxy, etc.) at both or one end or side of the silicone main chain depending on the modification type. The length of the silicone main chain can be adjusted to set the viscosity that exhibits the desired fluidity. Suitable modified silicone oils have a viscosity range of 4 to 2000 cps.

[0033] The modified silicone oil is represented by the following general formula (1):

[0034] (wherein part of R is, for example, a carboxy group (—COOH) or a phenol (C ６ H ５ -OH), and the remainder of R is a methyl group (-CH ３ ) For example, the compound represented by the following general formula (2):

[0035] and modified silicones having carboxy groups at both ends, represented by the following general formula (3):

[0036] The modified silicone may be a modified silicone having phenol at both ends, as represented by the following formula:

[0037] The modified silicone oil has a reactive functional group (e.g., a carboxy group, a vinyl group, an acrylic group, a methacrylic group, an amino group, a hydroxy group, an epoxy group, etc.) at least at one end or on a side chain of the silicone main chain (e.g., dimethylpolysiloxane). These reactive functional groups can covalently bond with other modified silicones in the vicinity, forming, for example, a crosslinked structure or a graft structure of the silicone main chain 22.

[0038] Furthermore, the base layer 14 may contain functional groups exhibiting the following reactivity instead of the above-mentioned vinyl groups (acrylic groups, methacrylic groups). These reactive functional groups can also form crosslinked structures, graft structures, etc. by covalent bonding (e.g., polymerization reaction, copolymerization reaction) with other reactive functional groups, such as carboxyl groups, amino groups, hydroxyl groups, and epoxy groups. Alkoxysilanes containing reactive functional groups are preferred as materials for forming such a base layer 14. Furthermore, alkoxysilanes such as tetraethoxysilane (TEOS) may be mixed in to reinforce fixation to the surface of the glass substrate 12. If the base layer 14 is formed using these materials, the reactive functional groups will form a silica structure (SiO ２ ) and is modified on the surface of the glass substrate 12. Note that hydrolysis of TEOS generates portions on the surface of the base layer 14 in which silicon (Si) is bonded to a hydroxyl group (—OH), and these portions can act as reactive functional groups.

[0039] The modified silicone is liquid immediately after the silicone oil is applied to the base layer 14. However, by heating or using a polymerization initiator, the reaction of the reactive functional groups proceeds moderately, as shown by the change from left to right in Figure 1. It is particularly preferable for the reactive functional groups to contain unreacted double bonds. A portion of the modified silicone in the lubricating layer 16 covalently bonds with the reactive functional groups in the base layer 14, resulting in a partial three-dimensional network structure of the modified silicone within the lubricating layer 16. In other words, the modified silicone oil in the lubricating layer 16 is held on the surface of the base layer 14 in a state where it is chemically adsorbed to the base layer through covalent bonds with the reactive functional groups in the base layer 14. It is also thought that a three-dimensional network structure is formed within the lubricating layer 16 through crosslinking or grafting structures (covalent bonding between the modified silicones). Furthermore, if the reactive functional groups are acrylic or methacrylic groups, a thermal reaction may also cause a polymerization reaction with the alkyl groups in the silicone main chain.

[0040] On the other hand, the lubricating layer 16 does not form a completely three-dimensional network structure, but rather a portion of the modified silicone remains in a one- or two-dimensional structure, and the silicone main chain portion (also referred to herein as the sliding portion) contributes to the sliding properties of the slide film 10. The modified silicone oil may remain partially in a liquid state. In the case of modified silicones with reactive functional groups at both ends, the crosslinking reaction with the surrounding modified silicones is relatively strong, so by mixing an appropriate amount of modified silicone with a reactive functional group at one end, it is possible to adjust the formation of the three-dimensional network structure of the lubricating layer 16 so that it does not become too large.

[0041] In this way, covalent bonds are partially formed within the lubricating layer 16, which was previously liquid, and the interactions between the polymers inside the lubricating layer 16 are strengthened.This action also acts as a three-dimensional obstacle, making it easier for the lubricating layer 16 to remain held in place by the base layer 14, and improving the durability of the slide film.

[0042] Since the surface of the base layer 14 of the slide film 10 is modified with reactive functional groups (e.g., vinyl groups), some of the modified silicone in the lubricating layer 16 is covalently bonded to these reactive functional groups in the base layer 14, and the three-dimensional network structure (such as a cross-linked structure or a graft structure) of the modified silicone formed in the lubricating layer 16 is firmly held in place by the base layer 14.

[0043] Therefore, a portion of the three-dimensional network structure of the modified silicone is directly and firmly held to the base layer 14, so that the one-dimensional or two-dimensional structure of the modified silicone of the lubricating layer 16 is more strongly held to the base layer 14.

[0044] As shown in FIG. 1, the lubricating layer 16 contains a modified silicone having a π-electron interacting moiety (e.g., a phenol group) at at least one end, and the surface of the base layer 14 is also modified with a π-electron functional group (e.g., a phenyl group).

[0045] The π-electron interacting portion (e.g., phenol group) of the modified silicone interacts with the π-electron functional group (e.g., phenyl group) of the base layer 14. For example, the hydrogen (H) atom of the OH group constituting the phenol group is bonded to an oxygen (O) atom with a large electronegativity, and therefore has a δ ＋ The π-electron functional group easily becomes charged with a π-electron charge and exhibits a strong interaction with the π-electrons of the π-electron functional group. This π-electron interaction allows the lubricating layer 16 to directly and densely coat the surface of the base layer 14. In addition to the phenol group, functional groups of modified silicones that exhibit π-electron interaction include a carboxy group and a hydroxy group.

[0046] In this way, a portion of the modified silicone is bonded to the base layer 14 through π electron interactions, but this bond is weaker than a covalent bond, and the fluidity of the main modified silicone is ensured.

[0047] In the synovial film 10 of this embodiment, the hydrophobicity and sliding properties of the silicone main chain allow liquids to slide off the synovial film 10 with a slight inclination of the surface of the glass substrate 12. The stable sliding performance of the modified silicone allows not only water droplets but also mayonnaise, soy sauce, carbonara sauce, ketchup, coffee, honey, curry sauce, and the like to slide off without remaining on the surface. Hot water, salt water, muddy water, ice, and blood also slide off in a similar manner. Furthermore, the combination of the base layer 14 and lubricating layer 16 of this embodiment allows the synovial film 10 to be well maintained along the surface of a substrate, even if the surface is curved.

[0048] 2 shows the steps for producing the slide film 10. As shown in step 1, a UV / O ３ In addition, PTES, VTMS (vinyltrimethoxysilane), TEOS, and ethanol (EtOH) are mixed and stirred to form a functional group (OH group). ２ O and aqueous HCl are added and further stirred to prepare a base layer solution. This base layer solution is applied to the surface of the glass substrate 12 by spin coating, dipping, squeegeeing, casting, or other methods, and then dried. This causes a hydrolysis reaction, forming and fixing the base layer 14 on the surface of the glass substrate 12. Note that, because the phenyl and vinyl groups are not involved in the hydrolysis reaction, the base layer 14 is modified with phenyl groups 14A and vinyl groups 14B in a pendant form.

[0049] In this way, the base layer 14 is formed on the surface of the glass substrate 12. Preferably, the glass substrate 12 has polar groups such as OH groups on its surface, as this enhances the bonding strength with the base layer 14. If the article is made of resin, it is advisable to form polar groups on the surface by subjecting it to plasma treatment.

[0050] In step 2, the base layer 14 is washed with ethanol to remove any residue that has not been fixed to the surface of the article, such as unreacted PTES, and modified silicone oil is applied dropwise onto the base layer 14 as a lubricant.

[0051] The modified silicone oil is, for example, a mixture of carboxy-modified silicone and phenol-modified silicone in a predetermined ratio by stirring, and may be diluted with an organic solvent or the like.

[0052] In step 3, the surface of the glass substrate 12 is tilted, for example, at an angle of 0.5 degrees, to allow excess modified silicone oil to slide off and be removed. This is because an excess lubricating layer 16 is formed when the modified silicone oil is applied. The thickness of the lubricating layer 16 can also be adjusted by changing the coating conditions. Furthermore, when diluting the modified silicone oil with a solvent such as methyl ethyl ketone, toluene, or a mixture thereof, the thickness of the lubricating layer 16 can also be adjusted by changing the dilution concentration. Finally, in step 4, a heat treatment is performed to a surface temperature of 300°C or less, thereby retaining the lubricating layer 16 on the base layer 14. This forms a slide film 10 with a thickness of approximately 0.5 to 2 μm on the glass substrate 12, allowing the liquid (water droplets) 40 to slide off the surface of the lubricating layer 16 due to the slight tilt of the glass substrate 12 surface.

[0053] In this embodiment, a π-electron interaction occurs between the phenyl group contained in the base layer 14 on the surface of the glass substrate 12 and the phenol group of the phenol-modified silicone of the lubricating layer 16, and a covalent bond occurs between the vinyl group contained in the base layer 14 and the carboxy group of the carboxy-modified silicone of the lubricating layer 16, so that the lubricating layer 16 is bonded to the base layer 14, resulting in a structure that is difficult to remove by simple wiping.

[0054] The carboxy-modified silicone of the lubricating layer 16 has a highly reactive organic group (carboxy group) introduced at its terminal, which partially covalently bonds with the vinyl group of the base layer 14 upon heat treatment. This covalent bond strengthens the molecular interactions within the slide film 10, improving weather resistance. Furthermore, when salt water is sprayed onto the slide film 10, the π-electron interaction between the lubricating layer 16 and the base layer 14 densely coats the base layer 14 with the lubricating layer 16, preventing salt water from penetrating the interface between the two and reducing the likelihood of a decrease in slide performance. In other words, good slide performance is maintained and the durability of the slide film is improved.

[0055] Furthermore, the slide film 10 according to this embodiment does not require the formation of irregularities on the surface of the glass substrate 12. Rather, the formation of the base layer 14 and the lubricating layer 16 promotes flattening, making it less likely for scattering loss to occur in the glass substrate 12. As a result, stable transmittance can be obtained, and improved optical properties are expected.

[0056] Examples The following describes the three different combinations of base layers and lubricating layers shown in Table 1 (Configurations 1 to 3).

[0057]

[0058] <Salt Spray Resistance Test and Weather Resistance Test> Sliding films shown in Table 1, Configurations 1 to 3, were formed on glass plates. Methyl ethyl ketone was used as the solvent. For example, the base layers of Configurations 1 to 3 were the same, with a mass ratio of phenyltriethoxysilane (PTES), vinyltrimethoxysilane (VTMS), and tetraethoxysilane (TEOS) of 0.5:0.5:2. In the lubricating layer of Configuration 1, the mass ratio of carboxy-modified silicone to phenol-modified silicone was 1:1. In Configuration 2, the mass ratio of methacrylic-modified silicone to carboxy-modified silicone was 1:1. In the lubricating layer of Configuration 3, only carboxy-modified silicone was used. The bonding process between the base layer and lubricating layer was performed in a heating furnace at 300°C for 10 to 20 minutes. The final coating weight of the slipping film was 0.05 to 0.20 mg / cm. ２ The thickness was in the range of 0.5 to 2.0 μm.

[0059] In the salt spray resistance test (based on JIS Z 2371:2015 "Salt Spray Test Method"), the synovial films of Configurations 1 to 3 were subjected to salt spray for 120 to 480 hours, and then the sliding properties of each synovial film were evaluated. In the weather resistance test (based on JIS D 0205 "Weather Resistance Test Method for Automotive Parts"), the synovial films of Configurations 1 to 3 were subjected to weather resistance tests for 240 to 620 hours, and then the sliding properties of each synovial film were evaluated. The sliding properties were evaluated by dropping water onto the synovial film, tilting the glass plate, and measuring the angle at which the water droplet began to slide (sliding angle), as shown in FIG. 3 . Seven water droplet diameters were used, ranging from 1 mm to 2.7 mm, and the sliding properties were evaluated based on the sliding angle at a water droplet diameter of 2 mm.

[0060] Configurations 4 and 5 are shown for comparison. The differences from Configurations 1 to 3 are that in Configuration 4, the base layer was formed of PTES and TEOS (mass ratio 1:2) and did not contain VTMS, and the lubricating layer in Configuration 4 was made of only dimethyl silicone, i.e., unmodified silicone. Furthermore, the base layer in Configuration 5 was formed of PTES and TEOS (mass ratio 1:2), as in Configuration 4, and the lubricating layer in Configuration 5 was prepared by mixing phenol-modified silicone, acrylic-modified silicone, and methacrylic-modified silicone in a mass ratio of 20:2:2.

[0061] The results of the salt spray resistance test and weather resistance test for comparative Configuration 4 are shown in Figures 4(A) and (B). Configuration 4 did not maintain its sliding properties after 240 hours of salt spray resistance testing, as shown in Figure 4(A). Furthermore, it did not maintain its sliding properties after 120 hours of weather resistance testing, as shown in Figure 4(B). When evaluating the solvent resistance of Configuration 4, a 2 mm diameter water droplet did not slide off after 1 minute of acetone immersion.

[0062] The results of the salt spray resistance test and weather resistance test for comparative Configuration 5 are shown in Figures 5(A) and (B). Configuration 5 did not maintain its sliding properties after 120 hours of weather resistance testing, as shown in Figure 5(B). Note that the salt spray resistance test (Figure 5(A)) was performed up to 120 hours, but no further testing was performed. However, given the results of the weather resistance test, it is unlikely that the sliding properties can be maintained for a long period of time. Regarding the solvent resistance of Configuration 5, the sliding angle of a 1.6 mm diameter water droplet was 40 degrees after 1 minute of acetone immersion, which was good.

[0063] 6A and 6B show the measurement results of the salt spray resistance test and the weather resistance test for the example of Configuration 1. Configuration 1 showed good sliding properties after 480 hours of the salt spray resistance test and 620 hours of the weather resistance test. Furthermore, the solvent resistance of Configuration 1 was good, with a sliding angle of a 1.6 mm diameter water droplet reaching 60 degrees after 1 minute of acetone immersion.

[0064] 7A and 7B show the measurement results of the salt spray resistance test and the weather resistance test for the example of the configuration 2. The configuration 2 showed good falling characteristics after 360 hours of the salt spray resistance test and 600 hours of the weather resistance test.

[0065] 8A and 8B show the measurement results of the salt spray resistance test and the weather resistance test for the example of configuration 3. Configuration 3 showed good falling characteristics after 480 hours of the salt spray resistance test and 600 hours of the weather resistance test.

[0066] Next, to explain the effects of the example, a comparative test was conducted using Configuration 6, which contains only covalent bonds (base layer: VTMS:TEOS = 1:2, lubricating layer: only carboxy-modified silicone). Figures 9A and 9B show the measurement results of salt spray resistance tests and weather resistance tests for Configuration 6 for comparison. As shown in Figure 9B, Configuration 6, which contains only covalent bonds, exhibited good sliding resistance even after 500 hours of weather resistance testing. However, as shown in Figure 9A, in the salt spray resistance test, sliding resistance could not be maintained at least after 120 hours.

[0067] In addition, a comparative test was conducted using Configuration 7, which only had π-electron interactions (base layer: PTES:TEOS = 1:2, lubricating layer: phenol-modified silicone). Figures 10(A) and (B) show the measurement results of salt spray resistance tests and weather resistance tests for Configuration 7 for comparison. Configuration 7, which only had π-electron interactions, was unable to maintain its falling properties after at least 120 hours in both the salt spray resistance test and the weather resistance test.

[0068] Therefore, when comprehensively evaluated based on the test results of the Examples in FIGS. 6 to 8 and the comparison results of FIGS. 4, 5, 9, and 10, it is clear that the samples of the Examples (Configurations 1 to 3) have effects that cannot be easily predicted by a simple combination of covalent bonds and π-electron interactions.

[0069] Next, a slide film identical to that of Configuration 1 (Configuration 1-1) and one with a different silane component ratio in the base layer (Configuration 1-2) were prepared, and the sliding properties after weather resistance testing were evaluated. Table 2 shows the respective configurations. In the base layer of Configuration 1-1, the mass ratio of PTES, VTMS, and TEOS was 0.5:0.5:2, while in the base layer of Configuration 1-2, the mass ratio was changed to 0.25:0.75:2. In other words, the mass ratio of the phenyl group (cyclic conjugated functional group) component to the vinyl group (reactive functional group) component contained in the base layer was 1:1 in Configuration 1-1 and 1:3 in Configuration 1-2.

[0070]

[0071] The modified silicones used in the lubricating layer were all manufactured by Shin-Etsu Chemical Co., Ltd., and in Configurations 1-1 and 1-2, a double-end phenol-modified silicone and a double-end carboxy-modified silicone were used in a mass ratio of 1: 1. In both Configurations 1-1 and 1-2, the modified silicone contained in the lubricating layer was diluted with methyl ethyl ketone (7.5 volume percent concentration) so that the concentration was 22.5 volume percent.

[0072] Figure 11(A) shows the measurement results of the weather resistance test for Configuration 1-1. Figure 11(B) shows the measurement results of the weather resistance test for Configuration 1-2. The slide films of Configurations 1-1 and 1-2 maintain the same level of slippage characteristics as Configuration 1 (up to 500 hours after the weather resistance test).

[0073] 10: Sliding film 12: Glass substrate 14: Base layer 14A: Phenyl group 14B: Vinyl group 16: Lubricating layer 40: Liquid to be slid down

Claims

1. A base layer formed on a substrate and a lubricating layer held by the base layer, wherein the base layer is obtained by modifying the surface of the substrate with reactive functional groups, the lubricating layer is composed of a polymer containing reactive functional groups capable of covalent bonding with the reactive functional groups of the base layer, a part of the reactive functional groups of the base layer and a part of the reactive functional groups of the lubricating layer are covalently bonded, the base layer contains a cyclic conjugated functional group modified on the surface of the substrate, The lubricating layer is δ ＋ and includes a polymer containing a hydrogen atom charged to A part of the cyclic conjugated functional group of the base layer and a part of the hydrogen atoms charged to δ of the lubricating layer are in π-electron interaction. ＋ A water lubricating film characterized by this.

2. The reactive functional group is at least one functional group selected from the group consisting of a carbon-carbon double bond-containing group, a carboxy group, an amino group, a hydroxy group, and an epoxy group. The water-slipping film according to Claim 1.

3. The base layer is silicon oxide (SiOₓ) containing the reactive functional group and the cyclic conjugated functional group. The water-slipping film according to Claim 1.

4. The lubricating layer is a modified silicone containing the reactive functional group and a hydrogen atom charged to the δ ＋ The water-skiing film according to claim 1, which is a modified silicone containing a hydrogen atom charged to the δ

5. The reactive functional group of the base layer is at least one functional group selected from the group consisting of a vinyl group, an acrylic group, a methacrylic group, a carboxy group, an amino group, a hydroxy group, and an epoxy group. The cyclic conjugated functional group of the base layer is a phenyl group. The water-slipping film according to Claim 1.

6. The reactive functional group of the lubricating layer is at least one functional group selected from the group consisting of a carboxy group, a vinyl group, an acrylic group, a methacrylic group, an amino group, a hydroxy group, and an epoxy group, and the δ ＋ The hydrogen atom charged to is part of at least one functional group selected from the group consisting of a carboxy group, a phenol group, and a hydroxy group. The water-skiing film according to claim 1.

7. The mass ratio of the component of the cyclic conjugated functional group of the base layer to the component of the reactive functional group of the base layer is 1:1 to 1:

3. The water-slipping film according to Claim 1.

8. An article having a surface coated with the water-slipping film according to any one of Claims 1 to 7.