Aluminum component protective agent and method for applying the aluminum component protective agent

Abstract

To provide an aluminum member protective agent which can suppress occurrence of white rust generated in an aluminum member used in the exterior of a vehicle such as an automobile, and a coating method for an aluminum protective agent.SOLUTION: An aluminum member protective agent contains a silicone component containing an alkoxy oligomer having a terminal polyfunctional alkoxysilyl group, and an organic solvent. When being dispersed in the organic solvent and applied to an aluminum member 1, the alkoxy oligomer having the terminal polyfunctional alkoxysilyl group uniformly coats the surface of the aluminum member 1. The mutual terminal polyfunctional alkoxysilyl groups of alkoxy oligomers applied onto the surface of the aluminum member 1 are hydrolyzed and condensed, so that crosslinking three-dimensionally progresses. The three-dimensionally crosslinked silicone component forms a protective film 3 densely coating the surface of the aluminum member, and blocks a causative substance of white rust from the aluminum member.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technical field of this specification relates to an aluminum component protectant that suppresses the occurrence of white rust on aluminum components used in the exterior of vehicles such as automobiles, and a method for applying the aluminum component protectant. [Background technology]

[0002] Aluminum components, which also serve as decorative elements with a metallic sheen, are sometimes used as exterior components for vehicles such as automobiles, for example, door moldings that make up door window frames, and roof rails installed on the roof for loading luggage. Due to external factors, aluminum components may develop spotty white rust on their surface. Patent Document 1 describes a method for polishing aluminum components to remove white rust that has formed on the surface of the aluminum component by polishing. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-130178 [Overview of the project] [Problems that the invention aims to solve]

[0004] However, the aluminum polishing method described in Patent Document 1 removes white rust that has formed on the surface of the aluminum component retrospectively. For this reason, there has long been a demand to suppress the occurrence of white rust on aluminum components used as exterior parts for vehicles.

[0005] The problems that the technology described herein aims to solve have been addressed in view of the above-mentioned points, and the objective is to provide an aluminum component protective agent and a method for applying the aluminum component protective agent that can suppress the occurrence of white rust on aluminum components used in the exterior of vehicles such as automobiles. [Means for solving the problem]

[0006] The aluminum component protectant according to the embodiment of this specification is an aluminum component protectant that suppresses the occurrence of white rust on aluminum components used in the exterior of vehicles such as automobiles, The product is characterized by containing a silicone component comprising an alkoxy oligomer having terminal polyfunctional alkoxysilyl groups, and an organic solvent.

[0007] According to the aluminum component protectant embodiment of this specification, since the aluminum component protectant contains an organic solvent, the alkoxy oligomer having terminal polyfunctional alkoxysilyl groups is dispersed in the organic solvent and, when applied to the aluminum component, uniformly coats the surface of the aluminum component. The applied alkoxy oligomer having terminal polyfunctional alkoxysilyl groups forms a protective film that densely covers the surface of the aluminum component. For this reason, the aluminum component protectant embodiment of this specification can suppress the occurrence of white rust on aluminum components used in the exterior of vehicles such as automobiles.

[0008] In the above-mentioned aluminum member protective agent, the alkoxy oligomer having the terminal polyfunctional alkoxysilyl group may contain a long-chain organic group.

[0009] According to this, when an aluminum component protective agent is applied to an aluminum component, it becomes flexible due to its long-chain organic groups, thereby improving its bending resistance.

[0010] Furthermore, in the above-mentioned aluminum component protective agent, the organic solvent may contain an aliphatic chain saturated hydrocarbon.

[0011] According to this, aliphatic chain saturated hydrocarbons can suitably disperse alkoxy oligomers having terminal polyfunctional alkoxysilyl groups, so that when the aluminum component protective agent is applied to the aluminum component, the alkoxy oligomers can be more uniformly coated onto the surface of the aluminum component.

[0012] Furthermore, the above-mentioned aluminum component protective agent may contain silicone oil.

[0013] According to this, because the aluminum component protectant contains silicone oil that acts as a leveling agent, when the aluminum component protectant is applied to an aluminum component, the alkoxy oligomer can be more uniformly coated on the surface of the aluminum component, and the protective film formed from the aluminum component protectant can have a smooth surface shape.

[0014] The method for applying the aluminum member protective agent according to the embodiment of this specification is characterized by applying the above-mentioned aluminum member protective agent to the aluminum member.

[0015] According to the application method for the aluminum component protective agent according to the embodiment of this specification, since the aluminum component protective agent contains an organic solvent, the alkoxy oligomer having terminal polyfunctional alkoxysilyl groups is dispersed in the organic solvent and uniformly coats the surface of the aluminum component when applied to it. The alkoxy oligomer having terminal polyfunctional alkoxysilyl groups applied to the surface of the aluminum component undergoes three-dimensional crosslinking through hydrolysis condensation of the terminal polyfunctional alkoxysilyl groups of each other. The three-dimensionally crosslinked silicone component forms a protective film that densely coats the surface of the aluminum component, blocking substances that cause white rust from reaching the aluminum component. Therefore, the application method for the aluminum component protective agent according to the embodiment of this specification can suppress the occurrence of white rust on the aluminum component.

[0016] Furthermore, in the method for applying the aluminum component protective agent described above, it is possible to omit the wiping finish after applying the aluminum component protective agent.

[0017] According to this method, the wiping finish can be omitted, making the process simpler.

[0018] Also, in the method for applying the aluminum member protective agent, the surface of the aluminum member can be subjected to anodizing treatment.

[0019] According to this, it is possible to suitably protect an anodized aluminum member that is inferior in alkali resistance.

Effect of the Invention

[0020] According to the aluminum member protective agent according to the embodiment of the present specification, it is possible to suppress the generation of white rust on the aluminum member used for the exterior of a vehicle such as an automobile.

Brief Description of the Drawings

[0021] [Figure 1] It is a model cross-sectional view of an aluminum member protected by a protective film formed from the aluminum member protective agent according to the embodiment of the present specification.

Mode for Carrying Out the Invention

[0022] Hereinafter, the aluminum member protective agent and the method for applying the aluminum member protective agent according to the embodiment of the present specification will be described. Note that the scope of the present invention is not limited to the scope disclosed in the embodiment. The aluminum member protective agent of the embodiment is applied to an aluminum member 1 used for a door molding that constitutes a door window frame of an automobile, a roof rail installed on the roof for loading luggage, a door knob, or a wheel of a tire, etc., and forms a protective film 3 that suppresses the generation of white rust on the aluminum member 1. Of course, the embodiment of the present specification is not limited to applications to automobiles, and can also be applied to motorcycles, railway vehicles, airplanes, etc. In the present specification, when representing the blending amount and blending ratio of the aluminum member protective agent, unless otherwise specified, it is in mass units and is represented in the state of a paint including volatile components. Further, “%” representing the blending unit means “mass %” unless otherwise specified.

[0023] The material of the aluminum component 1 to which the aluminum component protective agent is applied is not particularly limited, and it can be applied not only to aluminum (aluminum without intentionally added impurities) but also to aluminum alloys including duralumin, super duralumin, and ultra-super duralumin.

[0024] These aluminum components 1 are subjected to surface treatment 2 to enhance their strength and corrosion resistance. The surface treatment 2 of the aluminum components 1 is not particularly limited and can be applied to aluminum components 1 that have undergone anodizing (anodic oxidation coating), chemical conversion treatment, plating, or painting. Among these surface treatments 2, aluminum components 1 that have undergone anodizing treatment are particularly prone to developing spotted white rust on their surface. It is presumed that this spotted white rust is caused by alkaline components contained in yellow dust and PM2.5 blown in from the continent, and the conditions of Japan's hot and humid environment.

[0025] The aluminum component protective agent according to this embodiment contains a silicone component comprising an alkoxy oligomer having terminal polyfunctional alkoxysilyl groups, and an organic solvent.

[0026] Alkoxy oligomers having terminal polyfunctional alkoxysilyl groups are alkoxy oligomers obtained by polymerizing monomers that contain a polyfunctional alkoxysilyl group represented by the following general formula (1) at their terminal end. (RO) n -Si- (1) (In the formula, RO is a methoxy group or an ethoxy group, and n is 2 or 3.) In alkoxy oligomers having terminal polyfunctional alkoxysilyl groups, the polyfunctional alkoxysilyl groups bond to the surface of the aluminum member 1, and the polyfunctional alkoxysilyl groups undergo hydrolysis condensation, causing crosslinking to progress in a three-dimensional network. As a result, the alkoxy oligomer having terminal polyfunctional alkoxysilyl groups bonds to the aluminum member 1 and densely coats its surface, forming a protective film 3 that blocks substances causing white rust from the aluminum member 1. Therefore, the aluminum member protective agent according to this embodiment can suppress the occurrence of white rust on aluminum members 1 used in the exterior of vehicles such as automobiles.

[0027] The alkoxy group (RO) of the alkoxy oligomer having a terminal polyfunctional alkoxysilyl group is a methoxy group and / or an ethoxy group. The alkoxy group is not particularly limited, but in another embodiment, it can be a methoxy group, which has a fast hydrolysis condensation rate and can accelerate film formation time.

[0028] The polyfunctional alkoxysilyl group of the alkoxy oligomer is 2 (dialkoxysilyl group) and / or 3 (trialkoxysilyl group) depending on n in the formula, and is not particularly limited. In another embodiment, the alkoxy oligomer can be an alkoxy oligomer (T resin) having trialkoxysilyl groups that can easily form crosslinks three-dimensionally and densely coat the surface of the aluminum member 1.

[0029] Furthermore, the alkoxy oligomer having a terminal polyfunctional alkoxysilyl group may contain tetraalkoxysilane (Q unit) as a monomer. By containing tetraalkoxysilane as a monomer in the alkoxy oligomer, the crosslinking density of the crosslinks formed in a three-dimensional network can be increased, thereby increasing the strength of the protective film 3 formed from the aluminum member protective agent. The content of tetraalkoxysilane as a monomer in the alkoxy oligomer having a terminal polyfunctional alkoxysilyl group can be 1 to 10% by mass relative to the oligomer. If the tetraalkoxysilane content is less than 1% by mass relative to the oligomer, the effect of increasing the crosslinking density may not be confirmed. On the other hand, if it exceeds 10% by mass, the crosslinking density will be high, the protective film 3 will become hard, and the flexibility of the protective film 3 may be poor. In another embodiment, the content of tetraalkoxysilane as a monomer in the alkoxy oligomer having a terminal polyfunctional alkoxysilyl group can be 3 to 7% by mass relative to the oligomer.

[0030] The alkoxy oligomer having a terminal polyfunctional alkoxysilyl group may have a long-chain organic group containing alkylene. By having a long-chain organic group, the protective coating 3 formed from the alkoxy oligomer having a terminal polyfunctional alkoxysilyl group can be made flexible and have improved bending resistance.

[0031] The number of carbon atoms in the alkylene contained in the long-chain organic group can be 10 to 20. This is because the protective film 3 formed from the alkoxy oligomer having terminal polyfunctional alkoxysilyl groups can have appropriate flexibility. If the number of carbon atoms in the alkylene contained in the long-chain organic group is less than 10, the protective film 3 may not have sufficient flexibility, and its bending resistance may be poor. On the other hand, if the number of carbon atoms in the alkylene contained in the long-chain organic group exceeds 20, the protective film 3 may become too soft, making it easier for dirt and other debris to adhere to it, and its stain resistance may be poor. In another embodiment, the number of carbon atoms in the alkylene contained in the long-chain organic group can be 12 to 18.

[0032] The alkoxy oligomer can be contained in the aluminum component protectant at a concentration of 20 to 50% by mass. This is because the protective film 3 formed from the aluminum component protectant can effectively suppress the occurrence of white rust on the aluminum component, and the application workability of the aluminum component protectant can be improved. If the alkoxy oligomer content is less than 20% by mass relative to the aluminum component protectant, there is a large amount of organic solvent, which is a volatile component that does not form a film, requiring a large amount to be applied, which may cause the aluminum component protectant to drip and result in poor application workability. On the other hand, if the alkoxy oligomer content exceeds 50% by mass, the non-volatile content of the aluminum component protectant is high, increasing the viscosity of the aluminum component protectant, which may also result in poor application workability. In another embodiment, the alkoxy oligomer content relative to the aluminum component protectant can be 25 to 30% by mass.

[0033] In the aluminum component protective agent, the organic solvent is used to dilute and disperse the alkoxy oligomer, and the type of organic solvent is not particularly limited as long as it can disperse the alkoxy oligomer. In another embodiment, an aliphatic chain saturated hydrocarbon can be used as the organic solvent. Since aliphatic chain saturated hydrocarbons can suitably disperse the alkoxy oligomer, when the aluminum component protective agent is applied to the aluminum component 1, the alkoxy oligomer can be more uniformly coated onto the surface of the aluminum component 1. Furthermore, since aliphatic chain saturated hydrocarbons are less likely to adversely affect human health compared to aromatic hydrocarbons, they can contribute to the safety of workers applying the aluminum component protective agent.

[0034] The organic solvent can be contained in an amount of 50 to 80% by mass relative to the aluminum component protectant. This is because it can improve the application workability of the aluminum component protectant. If the organic solvent content is less than 50% by mass relative to the aluminum component protectant, the non-volatile content of the aluminum component protectant will be high, the viscosity of the aluminum component protectant will be high, and the application workability may be poor. On the other hand, if the organic solvent content exceeds 80% by mass, there will be a large amount of organic solvent, which is a volatile component that does not form a film, requiring a larger application amount, which may cause the aluminum component protectant to drip during application, and this may also result in poor application workability. In another embodiment, the organic solvent content relative to the aluminum component protectant can be 60 to 75% by mass.

[0035] Silicone oil reduces the surface tension of the aluminum component protectant. To reduce the surface tension of the aluminum component protectant, the silicone oil functions as a leveling agent. Dimethyl silicone oil or methylphenyl silicone oil can be used as the silicone oil; in another embodiment, dimethyl silicone oil, which has excellent volatility, can be used.

[0036] The silicone oil can be contained in the aluminum component protectant at a concentration of 3 to 10% by mass. This is because it can suitably improve the leveling properties of the aluminum component protectant. If the silicone oil content relative to the aluminum component protectant is less than 3% by mass, it may not be possible to suitably improve the leveling properties of the aluminum component protectant. On the other hand, if it exceeds 10% by mass, it may be an excessive amount and uneconomical. In another embodiment, the silicone oil content relative to the aluminum component protectant can be 4 to 8% by mass.

[0037] A curing catalyst may be added to the aluminum component protective agent to accelerate curing. The curing catalyst can be any catalyst that can accelerate the curing reaction of alkoxy oligomers, and oxides, amines, or metals can be used. In another embodiment, a metal catalyst with excellent curing properties can be used as the curing catalyst. In yet another embodiment, a titanium-based catalyst can be used among the metal catalysts, and among the titanium-based catalysts, a titanium organometallic compound catalyst can be used.

[0038] The curing catalyst can be added to the aluminum component protectant in an amount of 0.5 to 5% by mass. This is because it can suitably improve the curability of the aluminum component protectant. If the amount of curing catalyst added to the aluminum component protectant is less than 0.5% by mass, it may not be possible to suitably improve the curability of the aluminum component protectant. On the other hand, if it exceeds 5% by mass, it will be an excessive amount and may be uneconomical. In another embodiment, the content of the curing catalyst in the aluminum component protectant can be 0.8 to 2% by mass.

[0039] If the aluminum component protectant contains a curing catalyst, it can be a two-component material (main component and curing agent) in which the curing catalyst can be mixed with the aluminum component protectant immediately before application. By using a two-component material, the aluminum component protectant can suppress the acceleration of curing during storage. In this case, the main component can be a mixture of alkoxy oligomer and silicone oil, and the curing agent can be a mixture of curing catalyst and organic solvent.

[0040] Next, a method for applying the aluminum component protectant will be described. The aluminum component protectant can be applied to the aluminum component 1 by spray painting, brush painting, or spreading with a cloth. In another embodiment, brush painting can be used, which minimizes overflow of the aluminum component protectant during application and eliminates the need for masking tape.

[0041] The brush used for brush painting is not particularly limited, but it can be a brush pen with a refillable cartridge. This is because the aluminum component protectant can be supplied from the cartridge during application, allowing for continuous application. The material of the brush bristles can be animal hair or synthetic fiber, but it can be an oil-lipid synthetic fiber. This is because the aluminum component protectant adheres well to the brush, and the surface of the protective film 3 formed from the applied aluminum component protectant can be made smooth. Among oil-lipid synthetic fibers, polyester resin has high fiber rigidity and is easier to smooth, and in another embodiment, PBT (polybutylene terephthalate) resin can be used.

[0042] The amount of aluminum component protective agent to be applied is 0.1 to 20 g / m², calculated based on the non-volatile content of the alkoxy oligomer. 2 (Film thickness: approximately 0.1 to 20 μm) This is because it can suitably protect the aluminum component 1. Coating amount: 0.1 g / m 2 If the coating amount is less than 20 g / m², uneven coating may prevent the surface of the aluminum component 1 from being adequately covered, potentially resulting in insufficient protection of the aluminum component 1. On the other hand, if the coating amount is 20 g / m², 2 If the amount exceeds this, the aluminum component protectant may drip during application, potentially impairing the application process. In another embodiment, the application amount of the aluminum component protectant is 0.2 to 15 g / m². 2 (Film thickness: approximately 0.2 to 15 μm) can be set to this thickness, and in another embodiment, the coating amount can be 1 to 10 g / m². 2 (Film thickness: approximately 1-10 μm). For convenience, the film thickness is calculated using a density of 1 g / cm³ of non-volatile components of the alkoxy oligomer. 3 This was established and sought.

[0043] The applicator mixes the main component and hardener of the aluminum component protectant, fills the mixture into a brush pen cartridge, and applies the aluminum component protectant to the aluminum component 1 using the brush pen. During application, the aluminum component protectant is applied uniformly to the aluminum component 1 due to the leveling properties of the aluminum component protectant and the material of the brush bristles which easily smooths the aluminum component protectant. Therefore, it is not necessary to perform a wiping finish after applying the aluminum component protectant, and a protective film 3 can be obtained. The aluminum component protectant of this embodiment can be applied simply because the wiping finish can be omitted. [Examples]

[0044] For the aluminum component protective agents of the embodiments, test specimens were prepared using the test specimen preparation method described below, and application workability tests were conducted to form protective films 3. After that, finish evaluation tests and alkali drop tests were performed to evaluate the results. The properties of the alkoxy oligomers that serve as raw materials for the aluminum component protective agents are shown in Table 1, the composition of the organic solvents in Table 2, the composition of the silicone oils in Table 3, and the composition of the curing catalysts in Table 4. The types of applicators used for applying the aluminum component protective agents are shown in Table 5.

[0045] [Table 1]

[0046] [Table 2]

[0047] [Table 3]

[0048] [Table 4]

[0049] [Table 5] Method for preparing test specimens The test specimens were prepared by using an aluminum plate whose surface had been anodized as surface treatment 2. The aluminum component protectant was applied to the anodized surface using the applicator described in Table 5. During application, the test specimens were placed vertically to the ground while the aluminum component protectant was applied. The amount of coating was controlled by controlling the coating weight. The coating weight was 5 g / m², calculated based on the non-volatile content of the alkoxy oligomer. 2 The film thickness was set to approximately 5 μm. If the aluminum component protectant was a one-component material, it was applied directly using the applicator. If it was a two-component material (main component and hardener), the main component and hardener were mixed and immediately applied using the applicator. The test specimens coated with the aluminum component protectant were left to cure, meaning they were not wiped or finished before being used as test specimens.

[0050] Application workability test The application workability test was conducted by applying the aluminum component protectant to a substrate that was placed vertically to the ground during the preparation of the test specimens described above, and evaluating the application workability when the specified amount of aluminum component protectant was applied. The test results were evaluated as follows: ○ if there was no dripping of the aluminum component protectant and the painted surface was uniform; △ if there was no dripping of the aluminum component protectant but the appearance of a ripple-like pattern just before dripping could be observed on the painted surface; and × if the aluminum component protectant dripped.

[0051] Finishing evaluation test In the finish evaluation test, test specimens coated with an aluminum component protectant and whose application workability was confirmed were cured for two weeks under standard conditions (temperature: 23±2℃, humidity: 50±5%), and the finish was visually evaluated. The test results were evaluated as follows: ○ if the painted aluminum component protectant leveled and the surface of the protective film 3 had a uniform gloss, △ if the leveling was insufficient and the surface of the protective film 3 had poor gloss, and × if the protective film 3 had no gloss or the surface of the protective film 3 was uneven.

[0052] Alkaline drop test In the alkali drop test, 0.1 mL of a 0.01% by mass aqueous solution of sodium hydroxide was dropped onto the painted surface of a test specimen that had undergone the finish evaluation test. The specimen was then left to stand in a hot air circulating furnace at 80°C for 1 hour, and the changes due to the alkali were visually evaluated. The test results were evaluated as follows: ○ if no change was observed on the painted surface of the test specimen even when viewed under a stereomicroscope, △ if no change was observed visually but white spots (white rust) could be observed under a stereomicroscope, and × if white spots could be observed visually.

[0053] Test examples of aluminum component protectants are shown in Tables 6 and 7. Test examples 1 to 20 are examples, and test example 21 is a control (blank). Note that test examples 1 to 11 in Table 6 are one-component materials, and test examples 12 to 20 in Table 7 are two-component materials (main component and hardener).

[0054] [Table 6]

[0055] [Table 7] (Test examples 1-11) Test Examples 1-11 are single-component aluminum component protectants. Test Examples 1-7 contain an alkoxy oligomer and an organic solvent, while Test Examples 8-11 further contain silicone oil.

[0056] Test Example 1 is an aluminum component protective agent prepared by diluting a silicone component containing trimethoxysilane having an alkylene with 12 to 18 carbon atoms with the organic solvent isoparaffin (distillation properties: 80 to 140°C). The application workability was excellent with a PBT brush (cartridge), there was no dripping, and the painted surface was uniform. The finish evaluation showed insufficient leveling and poor gloss on the protective film 3 surface. Alkali drop resistance was good, with no change observed on the painted surface even when examined under a stereomicroscope. Although not indicated in the table, Test Example 1 required a longer time to touch dry compared to the two-component aluminum component protective agents (Test Examples 13-21).

[0057] Test Example 2 is an aluminum component protectant in which the silicone component is replaced with a silicone component containing trimethoxysilane having alkylene with 6 to 10 carbon atoms, as in Test Example 1. The evaluation showed that because the silicone component contains trimethoxysilane having alkylene with 6 to 10 carbon atoms, which has poor flexural resistance, the formed protective film 3 was hard, and although not indicated in the table, it had poor flexural resistance. Other evaluations were the same as in Test Example 1.

[0058] Test Example 3 is an aluminum component protectant in which the silicone component of Test Example 1 was replaced with a silicone component containing dimethoxysilane having alkylene with 12 to 18 carbon atoms. The evaluation showed that the alkali drop resistance was slightly inferior, although not visible to the naked eye, but white spots (white rust) were observed under a stereomicroscope. It is presumed that because Test Example 3 uses dimethoxysilane, many two-dimensional crosslinks were formed rather than three-dimensional ones, resulting in a less dense coating. Other evaluations were the same as in Test Example 1.

[0059] Test Example 4 is an aluminum component protectant in which the silicone component of Test Example 1 is replaced with a silicone component containing triethoxysilane having an alkylene with 12 to 18 carbon atoms. The evaluation was the same as in Test Example 1.

[0060] Test Example 5 is an aluminum member protective agent in which the silicone component in Test Example 1 is replaced with a silicone component containing an alkylene having 12 to 18 carbon atoms and trimethoxysilane having a methacryloxy group at its tip. Although an improvement in physical properties due to the methacryloxy group was expected, the evaluation was the same as in Test Example 1.

[0061] Test Example 6 is an aluminum member protective agent in which the silicone component in Test Example 1 is replaced with a silicone component containing an alkylene having 12 to 18 carbon atoms and trimethoxysilane having a glycidoxy group at its tip. The evaluation was the same as in Test Example 1, but the film strength was improved due to the glycidoxy group.

[0062] Test Example 7 is an aluminum member protective agent in which the isoparaffin of the organic solvent in Test Example 1 is replaced with an isoparaffin having a distillation property of 140 to 180 °C. The evaluation was the same as in Test Example 1, but due to the difference in isoparaffin, it took a slightly longer time to dry to the touch.

[0063] Test Example 8 is an aluminum member protective agent obtained by adding silicone oil (kinematic viscosity (25 °C): 1 mm 2 / s) to Test Example 1. The evaluation was that the finish evaluation was such that the aluminum member protective agent leveled due to the silicone oil, and the surface of the protective film 3 had a uniform gloss and was good. Other evaluations were the same as in Test Example 1.

[0064] Test Example 9 is an aluminum member protective agent in which the silicone oil in Test Example 8 is replaced with one having a kinematic viscosity (25 °C) of 5 mm 2 / s. The evaluation was that the alkali dripping property could not be confirmed visually, but white spots (white rust) were seen under a stereomicroscope and it was slightly inferior. It is presumed that a part of the silicone oil having a kinematic viscosity (25 °C) of 5 mm 2 / s did not volatilize and remained in the film, and a dense film was not formed. Other evaluations were the same as in Test Example 8.

[0065] Test Example 10 is an aluminum component protectant in which the silicone component was replaced from that of Test Example 8. The silicone component was a mixture of a silicone component containing trimethoxysilane having alkylenes with 12 to 18 carbon atoms and a silicone component containing dimethoxysilane having alkylenes with 12 to 18 carbon atoms, in a 1:1 ratio. The evaluation was the same as in Test Example 8.

[0066] Test Example 11 is an aluminum component protectant in which the silicone component was replaced from that of Test Example 8. The silicone component was a mixture of a silicone component containing trimethoxysilane having alkylenes with 12 to 18 carbon atoms and a silicone component containing dimethoxysilane having alkylenes with 12 to 18 carbon atoms, in a ratio of 7:17. The evaluation showed that the alkali dropability was slightly inferior, although not visible to the naked eye, white spots (white rust) were observed under a stereomicroscope. It is presumed that the high amount of dimethoxysilane prevented the formation of many three-dimensional crosslinks. Other evaluations were the same as in Test Example 8.

[0067] (Test examples 12-20) Test Examples 12-20 are two-component (main component and hardener) aluminum component protectants. Test Examples 12-17 examine changes in the raw materials contained, while Test Examples 13 and 18-20 examine changes in the application tools used to apply the aluminum component protectant.

[0068] Test Example 12 is a silicone component containing trimethoxysilane having alkylene with 12 to 18 carbon atoms as the main component, and silicone oil (kinematic viscosity (25°C): 1 mm 2The main component and hardener are contained in the hardener, which consists of isoparaffin (distillation properties: 80-140°C) as an organic solvent and titanium ethyl acetate as a curing catalyst. Immediately before application, the main component and hardener were mixed and applied using a PBT brush (cartridge). The application workability was excellent with the PBT brush, there was no dripping, and the painted surface was uniform. In terms of finish evaluation, it leveled well and the surface of protective film 3 had a uniform gloss. Alkali drop resistance was good, with no change observed on the painted surface even when checked with a stereomicroscope.

[0069] Test Example 13 is an aluminum component protectant obtained by replacing the silicone component in Test Example 12 with a silicone component containing an alkylene with 12 to 18 carbon atoms and a trimethoxysilane having a methacryloxy group at its tip. Although an improvement in physical properties due to the methacryloxy group was expected, the evaluation was the same as in Test Example 12.

[0070] Test Example 14 is an aluminum component protectant in which the silicone component of Test Example 12 is replaced with a silicone component containing an alkylene with 12 to 18 carbon atoms and a trimethoxysilane having a glycidoxy group at its tip. The evaluation was the same as in Test Example 12, but the film strength was improved due to the glycidoxy group.

[0071] Test Example 15 is a silicone component containing trimethoxysilane having an alkylene with 12 to 18 carbon atoms (containing tetramethoxysilane as a monomer at 5% by mass relative to the oligomer) and silicone oil (kinematic viscosity (25°C): 1 mm 2The main component and hardener are contained in the compound, and the hardener contains isoparaffin as an organic solvent (distillation properties: 140~180°C) and aluminum trisacetylacetonate as a curing catalyst. Immediately before application, the main component and hardener were mixed and applied using a PBT brush (cartridge). The application workability was excellent with the PBT brush, there was no dripping, and the painted surface was uniform. In terms of finish evaluation, it leveled well and the surface of protective film 3 had a uniform gloss. Alkali drop resistance was good, with no change observed on the painted surface even when checked with a stereomicroscope. Furthermore, because the silicone component contains tetramethoxysilane as a monomer at 5% by mass relative to the oligomer, the crosslinking density of the crosslinks formed in a three-dimensional network was increased, and the film strength was enhanced.

[0072] Test Example 16 is an aluminum component protective agent obtained by replacing the silicone component in Test Example 15 with a silicone component containing trimethoxysilane having an alkylene with 12 to 18 carbon atoms and a methacryloxy group at its tip (containing tetramethoxysilane as a monomer at 5% by mass relative to the oligomer). Although an improvement in physical properties due to the methacryloxy group was expected, the evaluation was the same as in Test Example 15.

[0073] Test Example 17 is an aluminum component protectant obtained by replacing the silicone component in Test Example 15 with a silicone component containing trimethoxysilane having 12 to 18 carbon atoms and a glycidoxy group at its tip (containing tetramethoxysilane as a monomer at 5% by mass relative to the oligomer). The evaluation was the same as in Test Example 15, but the film strength was further enhanced by the glycidoxy group.

[0074] Test examples 18-20 are evaluations of the aluminum component protective agent from test example 13, but with different application tools.

[0075] In Test Example 18, the coating was applied using an animal hair brush, and the results were evaluated. While the application process was smooth with no dripping and the surface of the painted area was uniform, the inability to supply the aluminum component protectant from the cartridge during application made it more cumbersome compared to using a PBT brush (cartridge). Other evaluations were the same as in Test Example 13.

[0076] In Test Example 19, the coating was applied using a sponge and evaluated. The application process was unsuccessful, resulting in uneven application and dripping. Consequently, the finished surface was uneven and bumpy. However, the alkali drop resistance was good, as no changes were observed on the coated surface under a stereomicroscope, indicating that the performance as an aluminum component protectant was met.

[0077] In Test Example 20, the coating was applied using a nonwoven fabric and evaluated. The application process was difficult, as it was not possible to apply a thin coat, resulting in dripping. Consequently, the surface of the protective film 3 was uneven and uneven. However, the alkali drop resistance was good, as no change was observed on the coated surface even when examined under a stereomicroscope, and the performance as an aluminum component protector was met.

[0078] (Test Example 21) Test Example 21 is a control (blank). In Test Example 21, an alkaline drop test was performed on an aluminum plate with an anodized surface without applying an aluminum component protectant. The evaluation of the alkaline drop test was that white spots (white rust) could be visually confirmed.

[0079] According to the aluminum component protectant of this embodiment, since the aluminum component protectant contains an organic solvent, the alkoxy oligomer having terminal polyfunctional alkoxysilyl groups is dispersed in the organic solvent and, when applied to the aluminum component 1, uniformly coats the surface of the aluminum component 1. The alkoxy oligomer having terminal polyfunctional alkoxysilyl groups applied to the surface of the aluminum component 1 undergoes three-dimensional crosslinking through hydrolysis condensation of the terminal polyfunctional alkoxysilyl groups of each other. The three-dimensionally crosslinked silicone component forms a protective film 3 that densely covers the surface of the aluminum component 1, blocking substances that cause white rust from the aluminum component 1. For this reason, the aluminum component protectant according to the embodiment of this specification can suppress the occurrence of white rust on aluminum components 1 used in the exterior of vehicles such as automobiles. [Explanation of symbols]

[0080] 1...Aluminum component, 2...Surface treatment, 3...Protective coating.

Claims

1. An aluminum component protective agent that suppresses the occurrence of white rust on aluminum components used in the exterior of vehicles such as automobiles, A silicone component containing an alkoxy oligomer having terminal polyfunctional alkoxysilyl groups, and an organic solvent, An aluminum component protective agent characterized in that the alkoxy oligomer contains an alkylene having 12 to 18 carbon atoms as a long-chain organic group.

2. The aluminum component protective agent according to claim 1, characterized in that the organic solvent contains an aliphatic chain saturated hydrocarbon.

3. The aluminum member protective agent according to claim 1, characterized by containing silicone oil.

4. A two-component material consisting of a main component and a hardening agent, The main component contains the alkoxy oligomer and the silicone oil, The curing agent contains a curing catalyst and the organic solvent, The aluminum member protective agent according to claim 3, characterized in that the curing catalyst is a metal catalyst.

5. A method for applying an aluminum member protective agent, characterized by applying the aluminum member protective agent described in any one of claims 1 to 4 to an aluminum member.

6. The method for applying an aluminum component protective agent according to claim 5, characterized in that no wiping finish is performed after applying the aluminum component protective agent.

7. The method for applying an aluminum member protective agent according to claim 5, characterized in that the surface of the aluminum member is anodized.

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