KR20230122489A - Paint composition for steel sheet of automobile having improved property - Google Patents

Abstract

The present invention relates to a paint composition that includes a carbon-based material, exhibits improved physical properties (corrosion resistance, weather resistance, adhesion, acid resistance and alkali resistance, etc.), has excellent workability, and is environmentally friendly. The coating composition according to the present invention is excellent in corrosion resistance, weather resistance, adhesion, acid resistance and alkali resistance, and long-term stability to the conductor. Therefore, the conductor treated with the coating composition according to the present invention is minimized in deterioration even when exposed to extreme environments, and can maintain its original state without deterioration for a long period of time.

Description

Paint composition for automotive steel sheet with improved physical properties {PAINT COMPOSITION FOR STEEL SHEET OF AUTOMOBILE HAVING IMPROVED PROPERTY}

The present invention relates to a paint composition that includes a carbon-based material, exhibits improved physical properties (corrosion resistance, weather resistance, adhesion, acid resistance and alkali resistance, etc.), has excellent workability, and is environmentally friendly.

Steel structures including steel, such as automobiles, are mostly exposed to corrosive environments. Accordingly, it is common to apply anti-corrosion treatment to the surface of a steel structure in order to improve the durability of the structure. Corrosion of steel structures generally means the occurrence of rust or red rust (Fe(OH) ₃ and Fe ₂ O ₃ ), which are caused by oxygen (O ₂ ) in the air and moisture (H _{2 )} . O), etc. This corrosion tends to be accelerated by polluted air, soot, salt in seawater, acid rain, and chemicals (acids, alkalis and salts).

As a method for suppressing corrosion of steel structures as described above, anti-corrosion pigments such as Kwangmyeongdan and zinc chromate, which passivate when water touches metal with a reaction suppression function, are used, or inflow of water or air that causes corrosion A sacrificial anode method using a flake antirust pigment such as aluminum or mica iron oxide, which functions as a barrier, or a metal pigment such as zinc, which has a higher ionization tendency than iron, is used as a cathode method. there is. In particular, in the case of automotive parts, wet plating methods such as electroless plating and electrolytic plating are mainly used as plating methods for suppressing corrosion of structures. Among them, the wet plating method has been preferred since the past because it has the advantage of obtaining a plating film with excellent adhesion.

However, in spite of the above advantages, in the wet plating method, most of the various chemicals used for wet plating contain heavy metal substances, and the direct cause of environmental pollution due to the discharge of industrial wastewater containing these heavy metal substances In addition to providing it, it has problems such as causing excessive expenditure of indirect capital for wastewater treatment. In order to improve the above problems, a coating method using an organic coating film has been developed as in Korean Patent Publication No. 10-2015-0072253, but this coating method does not have many types of corrosion inhibitors applicable to rust-preventive paints, and organic Substances included in the solvent cause harm to the human body and environmental pollution problems like heavy metals, and above all, due to excessive organic matter, there is a problem that the substrate is easily deteriorated by external environments such as sunlight, moisture, and calcium chloride, so its use is limited. there is

Accordingly, recently, as various new materials have been developed, paints using them have been developed, but there are no known research results that show satisfactory levels of function while solving existing problems.

10-2015-0072253 A

In one aspect, an object of the present invention is to provide a coating composition with improved corrosion resistance, weather resistance, adhesion, and acid resistance/alkali resistance.

In one aspect, an object of the present invention is to minimize deterioration such as corrosion, discoloration, and erosion of an object treated with a coating composition.

In one aspect, an object of the present invention is to provide an environmentally friendly coating composition that exhibits excellent performance.

In one aspect, an object of the present invention is to provide a paint composition having excellent dispersibility of particles in a paint, excellent bonding strength between components in a paint, and excellent stability of the composition.

In one aspect, the purpose of the present invention is to utilize the excellent mechanical/chemical/optical properties of carbon-based materials (CNT, graphene, graphene oxide, reduced graphene oxide) in this study, so that the manufacturing process is simple and commercially competitive. To provide an eco-friendly / high-quality paint with

In one aspect, an object of the present invention is to provide a coating composition optimized for protection of a steel sheet for automobiles.

The present invention provides a paint composition for a steel sheet in order to achieve the above object, the composition comprising: a first part containing graphenes; and a second part including xylene and toluene, wherein the first part is included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the second part, and the graphenes include at least one of the following characteristics. A composition is provided that: i) an average lateral size of 1-10 micrometers; ii) a thickness of 0.1 to 100 nanometers; iii) a specific surface area of 10 to 1000 m ² /g; and iv) a tap density of 0.001 to 1 g/cm ³ .

In addition, in order to achieve the above object, the present invention provides a paint composition for a steel sheet, wherein the graphenes include at least one of reduced graphene oxide and graphene nanoplatelets. to provide.

In addition, in order to achieve the above object, the present invention provides a paint composition for a steel sheet, wherein the reduced graphene oxide includes one or more of the following characteristics: i) an average lateral size of 1 to 10 micrometers (average lateral size); ii) a thickness of 0.1 to 5 nanometers; iii) a specific surface area of 200-1000 m ² /g; and iv) a tap density of 0.001 to 0.1 g/cm ³ .

In addition, in order to achieve the above object, the present invention provides a paint composition for a steel sheet, wherein the graphene nanoplatelet includes at least one of the following characteristics: i) an average lateral size of 1 to 10 micrometers (average size) lateral size); ii) a thickness of 10 to 100 nanometers; iii) a specific surface area of 10 to 50 m ² /g; and iv) a tap density of 0.01 to 1 g/cm ³ .

In addition, the present invention, in order to achieve the above object, the toluene and xylene of the second part, based on the total weight of the second part, respectively, 10 to 30% by weight and 30 to 60% by weight, for steel sheet A paint composition is provided.

In addition, in order to achieve the above object, the present invention provides a paint composition for steel sheet, wherein the xylene includes p-xylene.

In addition, in order to achieve the above object, the present invention provides a paint composition for steel sheet in which p-xylene is included in an amount of 10 to 40% by weight based on the total weight of the second part.

In addition, the present invention in order to achieve the above object, the second part, i) at least one selected from the group consisting of talc, ferric oxide, lead oxide and carbon black; and ii) at least one selected from the group consisting of ethylbenzene, petroleum, and petroleum acid.

In addition, in order to achieve the above object, the present invention provides a paint composition for a steel sheet, wherein the steel sheet includes a steel sheet for automobiles.

In addition, the present invention provides a method for manufacturing a paint composition for a steel sheet in order to achieve the above object, the manufacturing method comprising: a first part containing graphenes; and mixing a second part containing xylene and toluene.

In addition, the present invention in order to achieve the above object, the manufacturing method, a first dispersion step of mixing and dispersing the first part and the second part under a rotational speed of 500 ~ 4000rpm; and a second dispersion step comprising dispersing the mixture of the first part and the second part at a high pressure under a pressure condition of 1000 to 3000 bar after the first dispersion step.

The coating composition according to the present invention is excellent in corrosion resistance, weather resistance, adhesion, acid resistance and alkali resistance, and long-term stability to the conductor. Therefore, the conductor treated with the coating composition according to the present invention is minimized in deterioration even when exposed to extreme environments, and can maintain its original state without deterioration for a long period of time.

1 is a spectroscopic picture of reduced graphene oxide included in the coating composition of the present invention.
2 is a diagram showing a secondary dispersion method in preparing the coating composition of the present invention.
Figure 3a confirms the particle size dispersion state of composition 1 of the present invention with a grinder gauge.
Figure 3b is a FE-SEM photograph of a specimen coated with composition 1 of the present invention.
Figure 4a confirms the particle size dispersion state of composition 2 of the present invention with a grinder gauge.
Figure 4b is a FE-SEM picture of a specimen coated with composition 2 of the present invention.
5 is a result of measuring the thickness of the coating composition of the present invention.
6 is a spectroscopic picture of the present invention.
7 is a chemical resistance test result of the coating composition of the present invention.
8 is a paint salt spray test result of the paint composition of the present invention.
9 is an adhesion test result of the coating composition of the present invention.

Hereinafter, the present invention will be described in detail.

In one aspect, the present invention provides a paint composition for a steel sheet, the composition comprising: a first part containing graphenes; and a second part including xylene and toluene, wherein the first part is included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the second part, and the graphenes include at least one of the following characteristics. is the composition:

i) an average lateral size of 1-10 micrometers;

ii) a thickness of 0.1 to 100 nanometers;

iii) a specific surface area of 10 to 1000 m ² /g; and

iv) A tap density of 0.001 to 1 g/cm ³ .

In one aspect, the first part may be included in 0.01 to 100 parts by weight, or 0.01 to 50 parts by weight, or 0.01 to 30 parts by weight, or 0.01 to 10 parts by weight, or 0.01 to 10 parts by weight, when the second part is 100 parts by weight. It may be included in 5 parts by weight, or 0.05 to 5 parts by weight, or 0.1 to 5 parts by weight, but is not limited thereto.

In one aspect, the graphenes may include one or more of reduced graphene oxide and graphene nanoplatelets.

In one aspect, the graphenes may include only reduced graphene oxide or may include both reduced graphene oxide and graphene nanoplatelets.

Among carbon allotropes, graphite has a hexagonal structure, and its basal surface has sp ² covalent bonds with strong directional bonding force, but weak van der Waals bonds in the c-axis direction, so its thermal conductivity and thermal emissivity are anisotropic. It is known to represent

On the other hand, carbon nanotube (CNT) is a nanostructured material with sp2 covalent bonds and a rounded base surface, and has a thermal conductivity that is 10 times higher than that of ordinary graphite. It is used as an additive to improve performance in various fields such as films.

Graphene has a thin two-dimensional single sheet structure with a thickness of 0.2 nm in the hexagonal form of a plate-like structure in which carbon atoms are composed of regular hexagonal honeycombs. Compared to other conventional nano additives, graphene has excellent physical properties such as a large surface area, excellent mechanical strength, structural crystallinity, and high electron mobility. Therefore, various studies are being actively conducted to develop functional polymer composites using it. In addition, due to the excellent barrier properties of graphene, it is receiving high attention and interest as a new material that can replace existing pigments in the paint field.

In one aspect, when the first portion includes both reduced graphene oxide and graphene nanoplatelets, the amount of reduced graphene oxide included may be reduced. For example, when both reduced graphene oxide and graphene nanoplatelets are included in the first part, the content of reduced graphene oxide is 10% or more, or 20%, compared to the case where only reduced graphene oxide is included. or more, or more than 30%, or more than 40%, or more than 50%.

In one aspect, the reduced graphene oxide can include one or more of the following characteristics:

i) an average lateral size of 1-10 micrometers;

ii) a thickness of 0.1 to 5 nanometers;

iii) a specific surface area of 200-1000 m ² /g; and

iv) a tap density of 0.001-0.1 g/cm ³ .

In one aspect, the average lateral size of the reduced graphene oxide may be 1 to 10 micrometers, or 1 to 8 micrometers, or 2 to 8 micrometers, or 2 to 7 micrometers, or 2 to 6 micrometers. meter, or 3 to 5 micrometers, but is not limited thereto.

In addition, the reduced graphene oxide may have a diameter of 0.1 to 5 nanometers, or 0.1 to 4 nanometers, or 0.1 to 3 nanometers, or 0.2 to 3 nanometers, or 0.2 to 2 nanometers, or It may be 0.3 to 2 nanometers, or 0.35 to 2 nanometers, but is not limited thereto.

In addition, the specific surface area of the reduced graphene oxide may be 200 to 1000 m ² /g, or 300 to 1000 m ² /g, or 300 to 900 m ² /g, or 350 to 900 m ² /g, or 350 to 850 m ² /g, or 350 to 800 m ² /g, or 400 to 800 m ² /g, but is not limited thereto.

In addition, the bulk density of the reduced graphene oxide may be 0.001 to 0.1 g/cm ³ , or 0.001 to 0.05 g/cm ³ , or 0.003 to 0.05 g/cm ³ , or 0.003 to 0.03 g/cm ^{3 . _ _ _}

In addition, the graphene nanoplatelets may include one or more of the following characteristics:

i) an average lateral size of 1-10 micrometers;

ii) a thickness of 10 to 100 nanometers;

iii) a specific surface area of 10 to 50 m ² /g; and

iv) a tap density of 0.01 to 1 g/cm ³ .

In one aspect, the average lateral size of the graphene nanoplatelets may be 1 to 10 micrometers, or 2 to 10 micrometers, or 3 to 10 micrometers, or 4 to 10 micrometers, or 5 to 10 micrometers. meter, or 5 to 9 micrometers, or 6 to 8 micrometers, but is not limited thereto.

In addition, the graphene nanoplatelets may have a diameter of 10 to 100 nanometers, or 10 to 90 nanometers, or 10 to 80 nanometers, or 10 to 70 nanometers, or 20 to 70 nanometers, or It may be 20-60 nanometers, or 30-60 nanometers, or 30-50 nanometers, but is not limited thereto.

In addition, the specific surface area of the graphene nanoplatelets may be 10 to 50 m ² /g, or 15 to 50 m ² /g, or 15 to 45 m ² /g, or 20 to 45 m ² /g, or 20 to 40 m 2 /g. ² /g, or 20 to 35 m ² /g, or 20 to 30 m ² /g, but is not limited thereto.

In addition, the bulk density of the graphene nanoplatelets may be 0.01 to 1 g/cm ³ , or 0.05 to 1 g/cm ³ , or 0.05 to 0.7 g/cm ³ , or 0.05 to 0.5 g/cm ³ , or 0.07-0.5 g/cm ³ , or 0.07-0.4 g/cm ³ , or 0.08-0.4 g/cm ³ , or 0.08-0.3 g/cm ³ , or 0.1-0.3 g/cm ³ , or 0.1-0.25 g/cm 3 , cm ³ , or 0.1 to 0.2 g/cm ³ , but is not limited thereto.

In one aspect, toluene and xylene of the second part may be included in 10 to 30% by weight and 30 to 60% by weight, respectively, based on the total weight of the second part.

Specifically, the toluene of the second part may be included in 10 to 27% by weight, or 11 to 27% by weight, or 11 to 25% by weight, or 13 to 23% by weight based on the total weight of the second part, but is limited thereto it is not going to be

In addition, the xylene of the second part is 5 to 60% by weight, or 5 to 57% by weight, or 5 to 55% by weight, or 5 to 53% by weight, or 10 to 55% by weight based on the total weight of the second part. %, or 15 to 55% by weight, or 20 to 55% by weight, or 25 to 55% by weight, or 30 to 55% by weight, but is not limited thereto.

In addition, the xylene of the second part may include p-xylene (para-xylene).

The p-xylene may be included in 10 to 40% by weight based on the total weight of part 2, or 15 to 40% by weight, or 20 to 40% by weight, or 20 to 35% by weight, or 23 to 33% by weight It may be included in weight percent, but is not limited thereto.

In addition, in one aspect, the second part of the composition, i) at least one selected from the group consisting of talc, ferric oxide, lead (II) oxide and carbon black; and ii) one or more selected from the group consisting of ethylbenzene, petroleum, and petroleum acid, but is not limited thereto.

In addition, in one aspect, the petroleum may include kerosene, but is not limited thereto.

In one aspect, the petroleum acid may include naphthenic acid, but is not limited thereto.

In one aspect, the talc may be 1 to 20% by weight, or 3 to 20% by weight, or 3 to 17% by weight, or 5 to 15% by weight based on the total weight of the second part, but is limited thereto It is not.

In one aspect, the kerosene is 0.5 to 30% by weight, or 0.5 to 25% by weight, or 0.5 to 23% by weight, or 1 to 23% by weight, or 1 to 20% by weight, based on the total weight of part 2, or It may be included in 2 to 20% by weight, but is limited thereto.

In addition, the kerosene may include deodorized kerosene, and the deodorized kerosene is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, based on the total weight of part 2, or It may be included in 0.7 to 12% by weight, or 1 to 12% by weight, or 1 to 10% by weight.

In addition, the carbon black is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, or 0.7 to 12% by weight, or 1 to 12% by weight, based on the total weight of the second part, or It may be included in 1 to 10% by weight.

In addition, the trioxide is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, or 0.7 to 12% by weight, or 1 to 12% by weight, based on the total weight of the second part, or It may be included in 1 to 10% by weight.

In addition, the lead (II) oxide is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, or 0.7 to 12% by weight, or 1 to 12% by weight based on the total weight of the second part. %, or 1 to 10% by weight.

In addition, the ethylbenzene is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, or 0.7 to 12% by weight, or 1 to 12% by weight, based on the total weight of part 2, or It may be included in 1 to 10% by weight.

In addition, the petroleum acid is 0.5 to 20% by weight, or 0.5 to 15% by weight, or 0.5 to 13% by weight, or 0.7 to 12% by weight, or 1 to 12% by weight, or 1 to 12% by weight based on the total weight of part 2 ~10% by weight.

In addition, the second part may further include a metal hydroxide.

The metal hydroxide may be included in an amount of 0.01 to 10 wt%, or 0.05 to 10 wt%, or 0.05 to 5 wt%, or 0.1 to 4 wt% based on the total weight of the second part, but is not limited thereto.

The metal hydroxide may include potassium zinc chromate hydroxide (1-) (POTASSIUMHYDROXYOCTAOXODIZINCATEDICHROMATE), but is not limited thereto.

In addition, the metal hydroxide may be 2-butanone oxime (methyl ethyl ketoxime), but is not limited thereto.

In one aspect, the steel sheet may include a steel sheet for automobiles, but is not limited thereto. For example, it may include motorcycles, bicycles, kickboards, and the like.

In one aspect, the present invention is a method for preparing a paint composition for steel sheet.

The manufacturing method includes a first part including graphenes; and mixing a second part comprising xylene and toluene.

In addition, the manufacturing method may further include a first dispersing step of mixing and dispersing the first part and the second part at a rotational speed of 500 to 4000 rpm.

The first dispersing step may be performed in two steps.

Specifically, the first step of the first dispersion step may be performed at 500 to 2000 rpm, or 500 to 1500 rpm, or 700 to 1300 rpm, or 800 to 1200 rpm, or 900 to 1100 rpm, but is not limited thereto.

In addition, the second step of the first dispersion step may be performed at 2000 to 4000 rpm, or 2000 to 3500 rpm, or 2500 to 3500 rpm, or 2700 to 33 rpm, or 2800 to 3200 rpm, but is not limited thereto.

Each of the first step and the second step of the first dispersion step may be performed for 1 to 30 minutes, or 5 to 30 minutes, or 5 to 20 minutes, or 5 to 15 minutes, or 8 to 12 minutes, It is not limited thereto.

In addition, the manufacturing method may further include a second dispersion step comprising high-pressure dispersion of the mixture of the first part and the second part under a pressure condition of 1000 to 3000 bar after the first dispersion step.

The high-pressure dispersion may be performed at 1000 to 2500 bar, or 1000 to 2000 bar, or 1300 to 1700 bar, but is not limited thereto.

In one aspect, in the second dispersion step, the mixture of the first part and the second part that has passed through the first dispersion step is sprayed using a high-pressure pump, and the sprayed mixture is discharged through an interaction chamber.

The interaction chamber induces physical bonding between components (materials) contained in the first part and the second part that have undergone the first dispersion step, and has an effect of homogenizing graphene-type particles. For example, the diameter of the chamber may be 1000 micrometers or less, or 800 micrometers or less, or 600 micrometers or less, or 500 micrometers or less, or 400 micrometers or less.

Hereinafter, the present invention will be described in more detail with reference to the following preparation examples, examples and experimental examples. However, these preparation examples, examples, and experimental examples are provided only for illustrative purposes to aid understanding of the present invention, and the scope and scope of the present invention are not limited by the following examples.

[Production Example]

[Production Example 1] Production of Part 2

A first part was prepared by mixing the materials listed in Table 1 below.

chemical name Content (% by weight) One p-Xylene 25 2 Toluene 14 3 Xylene; Dimethylbenzene (Xylene) 15 4 Talc (not containing asbestos) 8 5 Kerosene 5 6 Carbon black 4 7 Triirontetraoxide 5 8 Ethylbenzene 5 9 Deodorized Kerosene 5 10 NAPHTHENIC ACIDS 5 11 Lead(II) oxide (Leadmonoxide) 5.1 12 Potassium zinc chromate (Potassiumhydroxyoctaoxodizincatedichromate(1-)) 2.9 13 2-Butanone oxime (Methylethyl ketoxime) One

* The content in Table 1 above is based on the total content of Part 1

p-xylene is 23 to 33% by weight, toluene 13 to 23% by weight, xylene 10 to 20% by weight, talc 5 to 15% by weight, kerosene, carbon black, triferric oxide, ethylbenzene, deodorized kerosene, naphthenic acid Lead oxide was used in an appropriate amount in the range of 1 to 10% by weight, and potassium zinc chromic acid hydroxide and 2-butanone oxime in the range of 0.1 to 4% by weight, respectively.

[Preparation Example 2] Preparation of paint composition

A paint composition was prepared by mixing and dispersing the second part prepared in Preparation Example 1 and the graphenes.

The contents of the components used in the paint composition are as shown in Table 2 below.

unit Composition 1 Composition 2 Reduced Graphene Oxide g 0.9 0.6 Graphene nanoplatelets g 0 28 Paint (first paint composition) g 600 600 excited g 70 70 total g 670.9 698.6

The paint composition manufacturing method is specifically as follows.

Reduced graphene oxide was added to the mixture of the second part and thinner, and a first dispersion was performed.

T.K. Reduced graphene oxide (composition 1), reduced graphene oxide and graphene nanoplatelets (composition 2) in the state where the second part and thinner were stirred at RPM 1,000 using Homo Mixer Mark II, Model 2.5 were each weighed and added.

After adding the reduced graphene oxide, stirring was performed at RPM 1,000 for 10 minutes, and then stirring was further performed at RPM 3,000 for 10 minutes to complete the first dispersion.

The first dispersed mixture was inlet and proceeded through the outlet through the interaction chamber through the high pressure pump to perform the second dispersion.

The role of the high pressure pump is to push the primary dispersed automotive paint into the high pressure pump at high pressure, and a pressure of 2000 bar is applied, preferably within 1500 bar.

Interaction chambers were used that had a diameter of less than 500 micrometers. After completing the secondary dispersion once, it was checked with a grinder gauge to see the dispersion state.

[Experimental example]

[Experimental Example 1] Confirmation of Dispersion State

As a result of checking the particle size gauge, it was confirmed that both Composition 1 and Composition 2 were excellent in dispersion compared to general automotive paint compositions.

However, among Composition 1 and Composition 2, it was confirmed that the dispersion state of Composition 1 was superior.

In addition, as a result of applying Composition 1 and Composition 2 to the specimen with a spray gun, respectively, and then enlarging the specimen with FE-SEM, it was confirmed that the state of the film was formed evenly compared to general automotive paint compositions.

However, among Composition 1 and Composition 2, it was confirmed that the film was formed more evenly when the composition 1 was treated.

[Experimental Example 3] Confirmation of chemical resistance

For acid resistance, after dissolving 10% sulfuric acid for reagent in distilled water, about 1 g was dropped on the surface formed by drying, and left at room temperature of about 20 degrees for 16 hours. Discoloration, swelling, peeling, etc. of the film surface were observed.

As a result, when composition 1 (21-03-20057-1) and composition 2 (21-03-20057-2) were treated, it was confirmed that there was no change in the coating film surface.

[Experimental Example 4] Paint salt spray test

KSC0224: Environmental test method Corrosion resistance was tested by spraying an aqueous solution of NaCl at about 36 degrees by the salt spray (cycle) test method.

As a result, it was confirmed that very little red rust occurred when the compositions 1(1) and 2(2) were treated.

[Experimental Example 5] Adhesion test

After cutting the coating surface into a rectangular grid pattern, the degree of separation from the material was measured and measured. The test was performed according to ASTM D3359, and when the composition was treated, it was confirmed that there was excellent adhesion with the conductor.

[Experimental Example 6] Measurement of film thickness

The thickness of the coating film was measured using KS M ISO 2808.

As a result, it was confirmed that a thinner coating film was formed when the composition 1 (#1) and composition 2 (#2) of Preparation Example were treated compared to the conventional general paint composition (#3).

Claims (11)

As a paint composition for steel sheet,
The composition,
A first part containing graphenes; and
a second part comprising xylenes and toluene;
The first part is included in 0.01 to 10 parts by weight when the second part is 100 parts by weight,
The graphenes include at least one of the following characteristics, a paint composition for steel sheet:
i) an average lateral size of 1-10 micrometers;
ii) a thickness of 0.1 to 100 nanometers;
iii) a specific surface area of 10 to 1000 m ² /g; and
iv) A tap density of 0.001 to 1 g/cm ³ . According to claim 1,
The graphenes,
A paint composition for a steel sheet comprising at least one of reduced graphene oxide and graphene nanoplatelets. According to claim 2,
The reduced graphene oxide includes at least one of the following characteristics, a paint composition for steel sheet:
i) an average lateral size of 1-10 micrometers;
ii) a thickness of 0.1 to 5 nanometers;
iii) a specific surface area of 200-1000 m ² /g; and
iv) a tap density of 0.001-0.1 g/cm ³ . According to claim 2,
The graphene nanoplatelet comprises at least one of the following characteristics, a paint composition for steel sheet:
i) an average lateral size of 1-10 micrometers;
ii) a thickness of 10 to 100 nanometers;
iii) a specific surface area of 10 to 50 m ² /g; and
iv) a tap density of 0.01 to 1 g/cm ³ . According to claim 1,
The toluene and xylene of the second part, respectively, based on the total weight of the second part,
10 to 30% by weight and 30 to 60% by weight, a paint composition for steel sheet. According to claim 1,
The xylene is a paint composition for steel sheet containing p-xylene. According to claim 6,
The p-xylene,
Based on the total weight of the second part, contained in 10 to 40% by weight, the paint composition for steel sheet. According to claim 1,
The second part,
i) at least one selected from the group consisting of talc, ferric oxide, lead oxide and carbon black; and
ii) A paint composition for steel sheet comprising at least one selected from the group consisting of ethylbenzene, petroleum and petroleum acid. According to claim 1,
A paint composition for a steel sheet, wherein the steel sheet includes a steel sheet for automobiles. A method for producing the paint composition for steel sheet according to any one of claims 1 to 9,
The manufacturing method,
A first part containing graphenes; and
A method for producing a paint composition for steel sheet comprising the step of mixing a second part containing xylene and toluene. According to claim 10,
The manufacturing method,
A first dispersion step of mixing and dispersing the first part and the second part at a rotational speed of 500 to 4000 rpm; and
After the first dispersion step, the method for producing a paint composition for steel sheet further comprising a second dispersion step comprising high-pressure dispersion of the mixture of the first part and the second part under a pressure condition of 1000 to 3000 bar.