KR20240085351A - Coating composition for a wire blade, manufacturing method of the same and wiper blade coated using the same - Google Patents

Abstract

The present invention relates to a coating composition for wiper blades, a method for manufacturing the coating composition, and a wiper blade coated with the coating composition. A coating composition for a wiper blade with improved wiping performance and durability of the coating, a method for manufacturing the coating composition, and It relates to a wiper blade coated with the coating composition.
The coating composition for a wiper blade according to an embodiment of the present invention includes a binder, a solid lubricant, and a solvent, and the solid lubricant includes modified graphene (AMG) and polytetrafluoroethylene (PTFE).

Description

Coating composition for a wiper blade, a manufacturing method thereof, and a wiper blade coated using the same {Coating composition for a wire blade, manufacturing method of the same and wiper blade coated using the same}

The present invention relates to a coating composition for wiper blades, a manufacturing method thereof, and a wiper blade coated using the same. More specifically, a coating composition for wiper blades with improved wiping performance and coating durability, a manufacturing method thereof, and a wiper blade coated using the same. It concerns coated wiper blades.

Wiper blades, conventionally used to clean automobile glass surfaces, are made of a rubber-like material and move left and right while in close contact with the glass surface by the power transmitted from the motor and wiper arm, removing moisture and dust attached to the glass surface. It is a type of important automobile part that removes dirt and secures the driver's visibility.

In order to improve the performance of the above-mentioned wiper blades, many efforts have been made to develop rubber technology and surface treatment technology. For example, there has been an attempt to improve the slip characteristics and wear resistance of the surface by hardening the surface by halogenating the surface of the blade. However, after hardening the surface, the durability of the blade was low, causing cracks to form on the blade surface during use, making it difficult to remove moisture.

Accordingly, when the surface of the wiper blade is treated with graphite or molybdenum disulfide as a solid lubricant, the initial wiping performance is excellent, but the wear resistance is low, so the lifespan of the wiper blade is reduced in a short period of time, requiring frequent replacement and causing chattering. ) phenomenon occurred.

In addition, increasing the amount of polymer resin improves durability, but reduces wiping performance, and conversely, decreasing the amount of polymer resin increases wiping performance but reduces durability. Ultimately, the two are in a relationship that offsets each other. Accordingly, a new coating layer that can increase both durability and wiping performance and also has sufficient quietness is required.

Republic of Korea Patent Publication No. 10-1998-0065568 (Publication date: 1998.10.15) Republic of Korea Patent Publication No. 10-2378026 (Registration date: 2022.03.19)

The present invention was designed to solve the problems described above, and effectively prevents the chattering phenomenon and noise of the wiper blade that occurs in general automobile glass as well as water-repellent coated automobile glass and improves the durability of the wiper blade at the same time. The purpose is to provide a wiper blade lubricating coating composition that can be used.

The technical problem to be achieved by the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

In order to achieve the above technical problem, an embodiment of the present invention includes a binder; solid lubricant; and a solvent. In the coating composition for a wiper blade, the solid lubricant includes modified graphene (Amine Modified Graphene; hereinafter referred to as 'AMG') and polytetrafluoroethylene.

The modified graphene (AMG) may contain more than 76 to less than 90 atomic% carbon, more than 5 to less than 10 atomic% oxygen, and 3 to 15 atomic% nitrogen.

The coating composition may include 0.2 to 3% by weight of binder, 0.1 to 0.3% by weight of modified graphene (AMG), 2 to 4% by weight of polytetrafluoroethylene (PTFE), and 90 to 97.7% by weight of solvent.

It may further include 0.1 to 3% by weight of reduced graphene, which is the solid lubricant.

It may further include 0.1 to 4% by weight of non-oxide graphene, which is the solid lubricant.

The solvent may be one or more selected from the group consisting of ethanol, isopropyl alcohol, acetic acid esters, methanol, toluene, xylene, xylene, hexane, and heptane.

Another method of the present invention for manufacturing a coating composition for a wiper blade includes preparing graphite oxide (s10); Preparing graphene flakes by peeling off the graphite oxide (s20); Preparing a graphene oxide suspension by mixing the graphene flakes and deionized water (s30); Manufacturing modified graphene (AMG) by surface modifying the graphene oxide (s40); Producing a colloid by dispersing the modified graphene (AMG) flakes (s50); And mixing the colloid of the modified graphene (AMG) flakes with polytetrafluoroethylene (PTFE), a binder, and a solvent to prepare a coating composition for a wiper blade (s60).

In another invention of the present invention, a wiper blade including a rubber layer 100, a coating layer 200 including the coating composition for a wiper blade is formed on the rubber layer 100.

According to an embodiment of the present invention, in the coating layer formed on the wiper blade, a first layer including modified graphene (AMG) and a second layer including polytetrafluoroethylene (PTFE) are formed, thereby cleaning the wiper blade. It has the effect of improving stability and durability, reducing noise and vibration when driving the wiper, and improving quietness by reducing the coefficient of friction.

The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

Figure 1 is a table showing the physical properties of modified graphene (AMG) of the present invention.
Figure 2 is an explanatory diagram showing the image and atomic bonding structure of modified graphene (AMG) of the present invention.
Figure 3 is a cross-sectional view of the main part of the wiper blade of the present invention.
Figure 4 is a cross-sectional SEM-FIB photograph of the main portion of the wiper blade of the present invention.
Figure 5 is a table showing the physical properties and atomic composition ratios of the modified graphene (AMG), non-oxidized graphene, and reduced graphene.
Figure 6 is a photograph of test equipment for evaluating initial wiping performance.
Figures 7 and 8 are tables showing the standards for evaluation grades of wiping performance.
Figure 9 is a photograph showing the results of the initial wiping performance test evaluation of Example 1 according to the present invention.
Figure 10 is a photograph showing the results of the durable wiping performance test evaluation of Example 5 according to the present invention.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are merely illustrative for the purpose of explaining the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention are It may be implemented in various forms and is not limited to the embodiments described herein. Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the present invention with reference to the accompanying drawings.

The present invention relates to a binder; solid lubricant; and a solvent, wherein the solid lubricant includes modified graphene (AMG) and polytetrafluoroethylene (PTFE).

The modified graphene (AMG) preferably contains more than 76 to less than 90 atomic% carbon, more than 5 to less than 10 atomic% oxygen, and 3 to 15 atomic% nitrogen, and |O-N| >3 is preferred.

Figure 1 is a table showing the physical properties of modified graphene (AMG) according to the present invention. As shown in Figure 1, the modified graphene (AMG) applied in the present invention is liquid and black at room temperature, and preferably has a zeta potential of 35 mV or more at pH 6.

Figure 2 is an explanatory diagram showing the image and atomic bonding structure of modified graphene (AMG). The modified graphene (AMG) has a thickness of less than 1 nm, has a single layer and functional groups, and forms a structure through covalent bonds, ionic bonds, and hydrogen bonds, respectively.

The absolute value of the zeta potential of general graphene oxide is -20mV or less, and the absolute value of the zeta potential of reduced graphene is -5 to -10mV or less, whereas the absolute value of the zeta potential of reduced graphene is -5 to -10mV or less. Modified graphene (AMG) has a functional group containing N bound to the surface, resulting in an absolute value of zeta potential of 35 to 58 mV or more. Accordingly, the dispersion stability of the coating liquid itself is improved and an excellent coating effect can be expected through self-bonding due to the electronegativity of the substrate.

The above-mentioned modified graphene forms a strong coating bond on the wiper rubber surface, improving the durability of the coating layer and protecting the rubber from friction and abrasion caused by the wiper operation, thereby improving the durability and wiping performance of the wiper.

In the composition of the coating composition, it is preferable to include 0.2 to 3% by weight of binder, 0.1 to 0.5% by weight of modified graphene (AMG), 2 to 4% by weight of polytetrafluoroethylene (PTFE), and 90 to 97.7% by weight of solvent. do. The solvent may be selected from one or more of the group consisting of ethanol, isopropyl alcohol, acetic acid esters, methanol, toluene, xylene, xylene, hexane, and heptane. If necessary, the solid lubricant may further include 0.1 to 3% by weight of reduced graphene or 0.1 to 4% by weight of non-oxidized graphene. For reference, Figure 5 is a table showing the physical properties and atomic composition ratios of the modified graphene (AMG), non-oxidized graphene, and reduced graphene.

The binder may be urethane resin, cellulose resin, or silicon resin, but is not necessarily limited thereto.

When the coating composition of the present invention according to the above configuration is applied to the upper surface of the rubber layer and dried, layer separation occurs depending on the density of modified graphene (AMG) and polytetrafluoroethylene (PTFE), which are solid lubricants, and forms within the coating layer. It is formed by dividing into a first layer containing modified graphene (AMG) and a second layer containing polytetrafluoroethylene (PTFE).

In addition, another method of the present invention for manufacturing a coating composition for a wiper blade includes preparing graphene flakes by peeling off the graphite oxide (s20); Preparing a graphene oxide suspension by mixing the graphene flakes and deionized water (s30); Manufacturing modified graphene (AMG) by surface modifying the graphene oxide (s40); Producing a colloid by dispersing the modified graphene (AMG) flakes (s50); And mixing the colloid of the modified graphene (AMG) flakes with polytetrafluoroethylene (PTFE), a binder, and a solvent to prepare a coating composition for a wiper blade (s60).

In the step (s40) of producing modified graphene (AMG) by surface modifying the graphene oxide, the modified graphene (AMG) contains more than 76 but less than 90 atomic % of carbon, more than 5 and less than 10 atomic % of oxygen, and 3 to 15 atomic % of nitrogen. It may be comprised of atomic percent.

The step (s20) of preparing graphene flakes by peeling off the graphite oxide can be performed by a chemical peeling method. For example, an improved method using phosphoric acid, sulfuric acid, and potassium permanate, which are widely known among chemical peeling methods, can be used. .

In the step (s40) of producing modified graphene (AMG) by surface modifying the graphene oxide, additives for modifying graphene are added to the graphene oxide suspension and stirred, followed by charged modification through a large-capacity circulating ultrasonic dispersion system. You will obtain graphene (AMG). As an additive, organic single molecules or polymers having amine, hydroxy, or azide groups can be used to modify graphene. Organic single molecules or polymers with amine groups include ethylenediamine, triethylamine, paraphenylenediamine, and 3,3',4,4'-tetraaminobiphenyl (3,3'). ,4,4'-tetraaminobiphenyl), 3,3',4,4'-tetraaminoterphenyl, benzidine, 1,5-diaminonaphthalene ( 1,5-diaminonaphthalene), (E)-4,4'-(diazene-1,2-diyl)dianiline ((E)-4,4'-(diazene-1,2-diyl)dianiline), Any one selected from the group consisting of ethylenediamine, 1,6-diaminohexane, and 1,8-diaminooactne can be used. . As an organic single molecule or polymer having a hydroxyl group, any one selected from the group consisting of poly(vinyl alcohol) (PVA), hot strong alkaline solutions (KOH, NaOH), hydroxyl-amine, etc. can be used. Organic single molecules or polymers having an azide group include 2-azidoethanol, 3-azidopropan-1-amine, 4-(2-azidoethoxy)-4-oxobutanoic acid, and 2-azidoethyl- Any one selected from the group consisting of 2-bromo-2-methylpropanoate, chlorocarbonate, azidocarbonate, dichlorocarbene, carbene, aryne, and nitrene can be used.

As described above, in the step (s60) of preparing a coating composition for a wiper blade by mixing polytetrafluoroethylene (PTFE), a binder, and a solvent with the colloid of the exfoliated modified graphene (AMG) flakes, the modified graphene (AMG) is preferably contained at 0.1 to 0.3% by weight, polytetrafluoroethylene (PTFE) at 2 to 4% by weight, binder at 0.2 to 3% by weight, and solvent at 90 to 97.7% by weight.

In another wiper blade of the present invention, a coating layer 200 including the coating composition for a blade according to the present invention is formed on the rubber layer 100.

Figure 3 is a cross-sectional view of the main portion of the wiper blade of the present invention, and Figure 4 is a cross-sectional SEM-FIB photograph of the wiper blade of the present invention. 3 and 4, the coating layer 200 formed on the wiper blade of the present invention includes a first layer 210 containing modified graphene (AMG) and a first layer 210 containing polytetrafluoroethylene (PTFE). It consists of two floors (220). The thickness of the first layer 210 is preferably 0.05 to 1㎛. In the SEM-FIB photo of Figure 4, it can be seen that the thickness of the first layer at 10K graphene coating is 0.85㎛ and 0.82㎛, respectively.

Example

Table 1 below shows the compositions of Examples 1 to 6, which are coating compositions for wiper blades according to the present invention, and Comparative Examples that do not contain modified graphene (AMG).

ingredient Content (parts by weight) Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 bookbinder urethane resin 2 0.2 1.5 3 1.5 1.5 1.5

solid
slush graphite 4 - - - - - - PTFE 3 3 3 3 3 3 3 AMG - 0.1 0.3 0.3 0.3 0.3 0.3 Reduced graphene - - - - 1.0 - - Non-oxidized graphene - - - - - 1.0 2.0
solvent ethanol 30 30 30 30 30 30 30 isopropyl alcohol 60 60 60 60 60 60 65

The performance evaluation test results for Examples 1 to 6 and Comparative Examples are shown in Table 2 below.

Test Items Comparative example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Initial wipeability 6/6 10/10 9/9 9/8 8/7 10/9 8/8 Durable wipeability
(After 500,000 times) 4/4 5/5 6/5 6/5 6/6 7/7 7/6 friction coefficient
(μ) 0.62 0.47 0.51 0.78 0.41 0.38 0.40 Quietness 2 3 3 2 4 5 5

1) Initial wiping performance evaluation

Figure 6 is a photograph of test equipment for evaluating initial wiping performance. For the initial wiping performance evaluation, a test device capable of implementing the actual vehicle installation state, such as KS R 3015 in the photo of FIG. 6, was used. With the wiper blade in the stationary position, water was evenly sprayed on the glass surface with a water sprayer, the wiper blade was activated, and a picture was taken with the camera within 1 second. Wiping performance was evaluated according to the wiping quality grade.

The results of the initial wiping performance evaluation are shown in Table 2 below. Figures 7 and 8 are tables showing the standards for evaluation grades of wiping performance. The initial wiping performance was determined by spraying water uniformly on the windshield of a vehicle in a test device that can be installed on an actual vehicle and determining the amount and shape of the water marks left when the wiper was activated according to the wiping quality grade standards. The higher the grade, the better the wiping performance.

Initial wipeability was graded 6 (6/6) in both comparative examples without modified graphene (AMG) in two tests, while Examples 1 to 6 according to the present invention all achieved grades 8 to 10. . All of the embodiments of the present invention had no traces of lines or wipes, or were observed only upon close inspection, and were evaluated as having no effect on driving at all.

Figure 9 is a photograph showing the results of the initial wiping performance test evaluation of Example 1. As shown in the photo in Figure 9, Example 1 was the highest grade and was confirmed to have no traces of lines or wipes.

2) Durable cleaning performance evaluation

A test device was used in accordance with the test device used in the wiper blade performance evaluation specified in KS R 3015. The test evaluation method for durable wiping performance was performed 500,000 times with water sprayed uniformly at 0.82L/min. The operating speed of the wiper blade was set at 40 cycles/min, and the wipeability and presence of joints were checked after 500,000 operations. As with the initial wiping performance evaluation above, durable wiping performance was evaluated according to the wiping quality rating table.

In a test device that can be installed on an actual vehicle, water is sprayed uniformly at 0.82L/min on the windshield of the vehicle, operated 500,000 times, and the amount and shape of the water marks left when water is sprayed and the wiper is operated are measured as wipe quality. It is judged according to grade standards, and the higher the grade, the better the wiping performance. After 500,000 operations, the wipe grade was 7/7 and 7/6 for Examples 5 and 6, which contain graphene as the main ingredient and a certain amount of BEG as an auxiliary ingredient, and it was confirmed that the durable wipe performance was superior to the comparative example. .

Figure 10 is a photograph showing the results of the durable wiping performance test evaluation of Example 6. As shown in the photo in Figure 10, even after 500,000 operations, almost no traces of lines or wipes were observed, confirming that driving was not affected.

3) Friction coefficient measurement

The coefficient of friction is measured by measuring the coefficient of kinetic friction between the glass and the wiper blade provided with a coating film on the lip. The kinetic friction coefficient is obtained by pressing a 10 cm long wiper blade rubber specimen on the glass surface with a load (P) of 0.15 N/cm and operating the relative speed between the glass surface and the wiper blade specimen in the range of 10 mm/s. It is determined by measuring the load (F) of the specimen rubbing against the glass surface using a load cell of a universal testing machine (UTM).

The friction coefficient was measured by measuring the dry friction coefficient (μ) against glass, and the comparative example that did not contain graphene measured a relatively high friction coefficient, while Examples 4, 5, and 6 had a coefficient of friction of 0.4 or less. It was measured with a low coefficient of friction. For reference, the friction coefficient has an effect on improving durable wiping performance and quietness.

4) Quietness evaluation

The coating composition prepared above is coated on 10 wiper blades, and then 1 day later, the wiper is operated and visually observed. The result is converted into a score as follows, and quietness is evaluated based on the average score. The higher the score, the better the quietness, and the evaluation criteria are as follows.

5 points: No noise at all

4 points: Occasional weak noise (noise audible right in front of the tester but not 1m away)

3 points: Continuously weak noise (noise audible right in front of the tester, but not 1m away)

2 points: Continuously generates a weak noise (noise can be heard 1m in front of the tester, but cannot be heard at a distance of 3m) or noise occurs when opening and closing at the same time.

1 point: Continuous strong noise (noise audible 3m in front of the tester, but not 5m away)

For each comparative example and example, the quietness was observed by operating the wiper blade 1000 times in a test device that can be installed on an actual vehicle after coating the wiper blade. Examples 4, 5, and 6, which contain graphene as the main component and reduced graphene and non-oxidized graphene as auxiliary components, were evaluated as excellent at grade 4 or higher, and Comparative Example and Example 3 were graded 2 or lower. The results showed poor quietness.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications and variations can be made by those skilled in the art without departing from the essential characteristics of the present invention.

Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but rather to explain it, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

100. Rubber layer 200: Coating layer
210: 1st floor 220: 2nd floor

Claims (11)

bookbinder; solid lubricant; In a coating composition for a wiper blade comprising a solvent,
A coating composition for a wiper blade, wherein the solid lubricant includes modified graphene (AMINE MODIFIED GRAPHENE) and polytetrafluoroethylene (PTFE).
According to paragraph 1,
The modified graphene is a coating composition for a wiper blade, characterized in that it contains more than 76 to less than 90 atomic% of carbon, more than 5 to less than 10 atomic% of oxygen, and 3 to 15 atomic% of nitrogen.
According to paragraph 1,
The coating composition is a coating for a wiper blade, characterized in that it contains 0.2 to 3% by weight of binder, 0.1 to 0.5% by weight of modified graphene, 2-4% by weight of polytetrafluoroethylene (PTFE), and 90 to 97.7% by weight of solvent. Composition.
According to paragraph 3,
A coating composition for a wiper blade, characterized in that it further comprises 0.1-3% by weight of reduced graphene, which is the solid lubricant.
According to paragraph 4,
A coating composition for a wiper blade, characterized in that it further comprises 0.1-4% by weight of non-oxide graphene, which is the solid lubricant.
According to paragraph 1,
A coating composition for a wiper blade, wherein the solvent is selected from the group consisting of ethanol, isopropyl alcohol, acetic acid esters, methanol, toluene, xylene, xylene, hexane, and heptane.
In the method of manufacturing a coating composition for a wiper blade,
Preparing graphite oxide (s10);
Preparing graphene flakes by peeling off the graphite oxide (s20);
Preparing a graphene oxide suspension by mixing the graphene flakes and deionized water (s30);
Manufacturing modified graphene (AMINE MODIFIED GRAPHENE) by surface modifying the graphene oxide (s40);
Dispersing the modified graphene flakes to produce a colloid (s50); and
Preparing a coating composition for a wiper blade by mixing polytetrafluoroethylene (PTFE), a binder, and a solvent with the colloid of the modified graphene flake (s60);
A method for producing a coating composition for a wiper blade, comprising:
In clause 7,
The modified graphene produced by surface modification of the graphene oxide is a coating composition for a wiper blade, characterized in that it contains more than 76 to less than 90 atomic% carbon, more than 5 to less than 10 atomic% oxygen, and 3 to 15 atomic% nitrogen. Manufacturing method.
In clause 7,
The coating composition for the wiper blade is a wiper characterized in that it contains 0.2 to 3% by weight of binder, 0.1 to 0.3% by weight of modified graphene, 2 to 4% by weight of polytetrafluoroethylene (PTFE), and 90 to 97.7% by weight of solvent. Method for producing a coating composition for a blade.
In the wiper blade including a rubber layer 100,
A wiper blade, characterized in that a coating layer 200 formed including the coating composition for a wiper blade according to any one of claims 1 to 6 is formed on the rubber layer 100.
According to clause 10,
The coating layer 200 is a wiper blade characterized in that it consists of a first layer 210 containing modified graphene and a second layer 220 containing polytetrafluoroethylene (PTFE).