KR20130081046A

KR20130081046A - Echo-functional compositions of top-coat paint and the method of producing the same

Info

Publication number: KR20130081046A
Application number: KR1020120002004A
Authority: KR
Inventors: 우정훈; 유병일
Original assignee: (주)감로파인케미칼
Priority date: 2012-01-06
Filing date: 2012-01-06
Publication date: 2013-07-16

Abstract

The present application relates to a coating composition, and more particularly, to a topcoat composition and a method for manufacturing the same, which can ensure the best function when applied to an aircraft or an automobile as an eco-friendly paint having a low VOC content.
It is possible to provide an eco-friendly paint composition with a low VOC content, which can provide an eco-friendly paint that can meet the VOC international standards, as well as reduce the use of solvents. In particular, it satisfies the physical properties required by coatings of aircraft or automobiles, and also solves cracks and isolation, copes with UV rays and oxidation, removes viscosity of paints, and bubbles in connection with top coats during painting. In addition to solving the problem of orientation and smoothness of the coating film, it is possible to provide an environmentally friendly functional coating composition further comprising a non-toxic additive and pigment.

Description

Eco-friendly functional top coat composition and preparation method thereof {ECHO-FUNCTIONAL COMPOSITIONS OF TOP-COAT PAINT AND THE METHOD OF PRODUCING THE SAME}

The present application relates to a coating composition, and more particularly, to a topcoat composition and a method for manufacturing the same, which can ensure the best function when applied to an aircraft or an automobile as an eco-friendly paint having a low VOC content.

Over the past few years, there has been a clear trend to reduce air pollution caused by volatile solutions released during the painting process. Particularly, as researches continue to focus on reducing or omitting the organic solvent used in the coating composition for the paint used in the priming treatment step and the top coating treatment step as a final treatment agent of a functional aircraft or a vehicle of a high quality, Or in the automobile industry, efforts have been made to develop environment-friendly paints for paints, and there has been a continuing need to ensure an appropriate level of functionality for the field of applied conductors applied along with the viewpoint of environment friendliness.

In particular, paints used in high-flying aircraft are required to have high corrosion resistance and weatherability, and these aircraft paints are subject to strict quality certification, only those that are certified. In the technology of eco-friendly coating system for eco-friendly aircraft with the current content of VOC (Volatile Organic Compounds, VOC), the demand is quantitatively comparable to the general use in automobiles and automobiles. As the quality of the paint is functionalized and advanced, it is necessary to have the outer skin, high corrosion resistance and weather resistance of the coating film having similar performance, and as a result, many functional paints have been developed. Paints that can be painted without or using oil-based solvents are being developed. In 2012, the market growth rate is estimated at 220%, considering only the aircraft, and the market growth rate is estimated at 220%. In order to secure competitiveness, the development of domestic technology is indispensable.

As VOCs are regulated as environmental pollutants as a component that evaporates into the air including a lot of oil-based agents, various products that can replace or reduce their use are under development. In the case of automotive paints, the VOC content standard is regulated to be lowered from 850 g / L in 2005 to 780 g / L in 2010, especially in the case of top-basecoat. It is regulated to decrease from 650 g / L in 2005 to 500 g / L in 2010. Especially in the case of aircraft paints according to the revised standard, VOC content according to the standard viscosity is up to 340 for primer. In the case of g / L, the top-coat base is required to lower to 420g / L.

Recently, a high solid paint has been proposed while lowering the VOC content, in order to enable spray coating while using less solvent containing VOC. However, since the high solid type resin is required to be cracked or isolated, to cope with ultraviolet rays or oxidation, to remove the viscous paint, to counteract bubbles, and to have a disadvantage in terms of the orientation of the luminous material and the smoothness of the coating film compared with the rosolid resin, The hardenability of the undercoat paint and especially the topcoat paint must be controlled in order to secure the function of the paint. Especially, the selection and composition of the undercoat and topcoat paint are important factors for solving the problem.

In other words, in order to meet the restriction of the VOC content in order to comply with environment-friendly regulations, it is necessary to reduce the content of the solvent used in the past. In the case of using the existing paint and hardener resin (high viscosity), the viscosity is deviated from the viscosity level due to the decrease of the solvent amount , There is a need to simultaneously solve the difficulties to maintain the function appropriate to the environment of the field to which the conductor is to be applied.

In this regard, the Republic of Korea Patent No. 0674173 proposes a "basecoat coating composition and a color basecoat coating composition (hereinafter referred to as the prior art) comprising the same, '' in detail i) a polyester resin having a hydroxyl group 10-30 wt%, ii) 5-30 wt% cellulose acetate butyrate, iii) 1-3 wt% polyolefin wax, iv) at least selected from the group consisting of rheology modifiers, surface modifiers, adhesion promoters, wet dispersants 1 to 5% by weight of one additive, and iv) extra solvent. However, the prior art uses an additional solvent, for example, ketones, esters, ethers, hydrocarbons, and the focus is on securing the color, the characteristics of the metallic orientation in that cellulose acetate butyrate is used Although it can be improved, it does not solve the problem of ease of operation and reduction of VOC content through low viscosity, and in particular, there is no suggestion of a technology that can simultaneously solve high corrosion resistance and weather resistance that can be applied to an aircraft.

As described above, in developing an environmentally friendly coating system having a low VOC content, consideration is given to lowering the viscosity of the resin for the undercoat base to reduce the viscosity, and also to improve the interaction of the curing agent and the lowering point of the curing agent, In connection with the work, it is very necessary to present the technology to secure the physical properties of the object to be carried by the aircraft or automobile, but there is no alternative yet.

The present application was derived to solve the above problems, to provide an environmentally friendly top coating composition that can reduce the use of the solvent to meet the VOC content restriction standard.

In particular, it satisfies the physical properties required by coatings of aircraft or automobiles, and it is necessary to solve cracks and isolation, cope with ultraviolet rays and oxidation, remove viscosity of paints, and prevent air bubbles in connection with undercoating during painting. In addition to solving the problem of the orientation and smoothness of the coating film, and to provide an environmentally friendly top coating composition further comprising a non-toxic additive and pigment.

However, the problem to be solved by the present application is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the said subject, 1st aspect of this application is aliphatic with respect to 100 weight part of polyester main resins whose hydroxyl group is 150-200 (mg KOH / g) and viscosity is 1000-2000 (cps / 25 degreeC). It is possible to provide a top coat composition comprising 50 to 70 parts by weight of a polyisocyanate curing agent.

In one embodiment, the polyester main resin may be prepared by adding nitrogen to 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid, It is not limited to this.

In one embodiment, the aliphatic polyisocyanate curing agent may be one or more selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate, It is not limited to this.

In one embodiment, the aliphatic polyisocyanate curing agent, based on 100% by weight of aliphatic polyisocyanate curing agent,

One or more selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate may include 60 to 70 wt%, but is not limited thereto. It is not.

In one embodiment, to 100 parts by weight of the polyester main resin, titanium dioxide 75 to 125 parts by weight, 5 to 10 parts by weight of catalyst, 10 to 15 parts by weight of additives, and 125 to 175 parts by weight of a diluent May be, but is not limited thereto.

The second aspect of the present application, S1) neopentylglycol 35 to 42 parts by weight, adipic acid 15 to 30 parts by weight, and 20 to 25 parts by weight of isophthalic acid while maintaining the temperature by heating to 140 ~ 240 ℃ while maintaining the reaction Preparing a polyester main resin; And S2) mixing 50 to 70 parts by weight of an aliphatic polyisocyanate curing agent with respect to 100 parts by weight of the polyester-based resin prepared, providing a method for preparing a top coat composition.

In one embodiment, the step of preparing the aliphatic polyisocyanate curing agent, hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate based on 100% by weight of aliphatic polyisocyanate curing agent At least one selected from the group consisting of isocyanates may be a step prepared by including 60 to 70 wt%, but is not limited thereto.

In one embodiment, the method of manufacturing the top coat composition, after the step S2), titanium dioxide 75 to 125 parts by weight, catalyst 5 to 10 parts by weight, additives 10 to 15 parts by weight, and diluent 125 to 175 parts by weight Adding step; may be to include additional, but is not limited thereto.

The third aspect of the present application may provide an aircraft or an automobile, including the top coat composition, but is not limited thereto.

According to the present invention, it is possible to provide an environmentally friendly coating composition having a low VOC content, thereby not only meeting the VOC international standard but also providing an environmentally friendly coating material capable of reducing solvent use.

In particular, it satisfies the physical properties required by coatings of aircraft or automobiles, and also solves cracks and isolation, copes with UV rays and oxidation, removes viscosity of paints, and bubbles in connection with top coats during painting. In addition to solving the problem of orientation and smoothness of the coating film, it is possible to provide an environmentally friendly functional coating composition further comprising a non-toxic additive and pigment.

Hereinafter, embodiments and examples of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention.

It should be understood, however, that the present invention may be embodied in many different forms and is not limited to the embodiments and examples described herein.

Throughout this specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

Throughout this specification, when a step is located “on” or “before” another step, it is not only when a step is in direct time-series relationship with another step, but also as a mixing step after each step. The order of steps includes the same rights as if they were in an indirect time series relationship in which the time series order could be reversed.

As used throughout this specification, the terms “about”, “substantially”, and the like, are used at, or in the vicinity of, numerical values when manufacturing and material tolerances inherent in the meanings indicated are given, and an understanding of the invention Accurate or absolute figures are used to help prevent unfair use by unscrupulous infringers. The term " step " or " step of ~ " used throughout the specification does not mean " step for.

In order to achieve the said subject, 1st aspect of this application is aliphatic with respect to 100 weight part of polyester main resins whose hydroxyl group is 150-200 (mg KOH / g) and viscosity is 1000-2000 (cps / 25 degreeC). It is possible to provide a top coat composition comprising 50 to 70 parts by weight of a polyisocyanate curing agent. In general, the polyester resin is a kind of alkyd resin produced by the combination of an alcohol and an acid, and is generally referred to as polyester, so the term "polyester resin" is used herein, but is not limited thereto.

In general, polyester resins are excellent in durability and weather resistance, and have various advantages such as flexible and tough properties and excellent glossiness. However, it is common to use a large amount of VOC as the above-mentioned solvent in order to use a polyester resin, so as to reduce the VOC content, while having a low viscosity to maintain the mechanical properties of the polyester in aircraft or vehicles, etc. Need to make

The polyester resin has a reaction scheme as shown in the following [Formula 1], a polyester resin is produced by esterification of an acid such as Phthalic anhydride and a polyfunctional base such as Trimethylol propane, and by adjusting the OH Value, Through the reaction skin as shown in [Formula 2], by reacting with an aliphatic polyisocyanate which is a curing agent, it is possible to produce a top coat as described herein as a polyurethane paint.

[Formula 1]

R- CO - OH + R ' - OH → R- CO -O- R '

[Formula 2]

R-N = C = O + R ' - OH → R- NH - CO -O- R '

Isocyanate Polyester Resin Polyurethane

The polyester main resin, the hydroxyl group is 150 ~ 200 (mg KOH / g), the viscosity is 1000 ~ 2000 (cps / 25 ℃), the glass transition temperature is preferably 10 to 20 ℃, but is not limited thereto no. The hydroxyl group has a hydroxyl group reactive component in the coating composition according to the present application to improve the interlayer adhesion by cross-linking through the hydroxyl group. The adhesion improvement is also closely related to the glass transition temperature and content of the resin. If the glass transition temperature of the polyester resin is less than 10 ℃ can improve the adhesion to the surface spreadability and internal stress of the coating film, but may result in poor results in drying, appearance, etc. of the coating film. On the other hand, if the glass transition temperature exceeds 20 ℃, there is a problem that the adhesion and impact resistance is significantly lowered due to the increase in hardness of the coating film. Therefore, the glass transition temperature of the polyester resin of the present invention is preferably 10 to 20 ℃, but is not limited thereto. Therefore, the viscosity of the paint can be lowered by mixing the polyester main resin and the curing agent, and it is possible to manufacture an eco-friendly functional paint of low VOC.

The polyester main resin may be a linear alcohol such as 1,6 hexanediol, polypropylene glycol (PPG), polyethylene glycol (PEG), and the like, and also trimethylol propane. It can be used with, in this case, the existing high viscosity highly-branched polyester resin can be prepared as a low-branched polyester resin.

In one embodiment of the present application, the polyester main resin, may be prepared by adding nitrogen to 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid. However, it is not limited thereto. The polyester main resin having a hydroxyl group and a specific viscosity and a constant glass transition temperature is charged with nitrogen at 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid. It can be prepared while, a more detailed manufacturing method will be described in detail in the method for producing a topcoat composition of the second aspect of the present application. Conventional high viscosity polyester resins have limitations in VOC regulation and are difficult to secure their physical properties. Therefore, in order to manufacture high solid low viscosity polyester-based resins, it is necessary to prepare acids and alcohols having the same components and composition ratios as above. It was confirmed that the polyester main resin of the present invention prepared by selecting can maintain excellent physical properties when used in the aircraft or automotive subjects with the lowest VOC content.

The aliphatic polyisocyanate curing agent may be 50 to 70 parts by weight with respect to 100 parts by weight of the polyester-based resin, using an isocyanate having high reactivity and low viscosity to reduce the VOC content and to be used in aircraft or automobiles Paint compositions can be prepared. When the aliphatic polyisocyanate curing agent is less than 50 parts by weight based on 100 parts by weight of the polyester main resin, there may be problems such as drying time and durability, and when the aliphatic polyisocyanate curing agent exceeds 70 parts by weight, solvent miscibility, catalytic activity, There may be problems such as durability.

In one embodiment of the present application, the aliphatic polyisocyanate curing agent may be one or more selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate. However, it is not limited thereto. In an exemplary embodiment, the aliphatic polyisocyanate curing agent is hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate with respect to 100% by weight of aliphatic polyisocyanate curing agent. One or more selected from the group consisting of, but may include 60 to 70% by weight, but is not limited thereto. Numerical limitation is that the components and composition of the aliphatic polyisocyanate can ensure drying time, glossiness, friability, flexibility, solvent resistance, heat resistance, low temperature bendability, acceleration resistance stability, and the like. .

In one embodiment of the present application, the topcoat composition of the present application, 75 to 125 parts by weight of titanium dioxide, 5 to 10 parts by weight of catalyst, 10 to 15 parts by weight of additives, and diluent based on 100 parts by weight of the polyester main resin 125 to 175 parts by weight may be additionally included, but is not limited thereto.

The titanium dioxide preferably contains 75 to 125 parts by weight with respect to 100 parts by weight of the polyester main resin, the titanium dioxide serves to perform the function of a white pigment, if less than 75 parts by weight for painting There may be a problem that the hiding power may be poor, and if it exceeds 125 parts by weight, there may be a problem of increase in viscosity, precipitation of the top coat composition.

The catalyst may use a variety of materials to optimize the physical properties of the topcoat, in the embodiment of the present invention, the catalyst may be dibutyl tin dilaurate as a drying accelerator, but is not particularly limited The catalyst is the poly With respect to 100 parts by weight of the ester-based resin, it is preferable to include 5 to 10 parts by weight, when less than 5 parts by weight may have a problem of poor drying, when it exceeds 10 parts by weight, the pot life is short, the gloss is lowered There may be a problem of an increase in the viscosity of the top coat composition, poor storage.

The additive may be various substances such as, but not limited to, a coloring agent, a dispersant, a precipitation inhibitor, a defoaming agent, and a leveling agent. In one embodiment of the present application, the additive may include, but is not limited to, unsaturated polycarboxylic acid-based dispersants, bentonite-based precipitation inhibitors, acrylic vesicles, and polyacrylic leveling agents. The additive may include 10 to 15 parts by weight with respect to 100 parts by weight of the polyester main resin, and when the additive is less than 10 parts by weight, there may be a problem in that it is difficult to achieve the desired additive purpose, and 15 parts by weight If it exceeds, there may be a problem that the viscosity of the top coat composition becomes high.

The diluent may be used 125 to 175 parts by weight based on 100 parts by weight of the polyester main resin, to reduce the viscosity of the top coat composition within the above numerical range, to improve the flowability, defoaming properties of the paint in use, parts Improves penetration, and induces the effective action of the filler, the type is methyl amyl ketone 5 ~ 7%, ethyl 3-ethoxy propionate 1 ~ 3%, methylpropyl ketone 5 ~ 7%, xylene 1 3% by concentration, dimethyl carbonate 0.1 ~ 0.5% by concentration of VOC exempt substances may be mixed, but is not limited thereto.

Another aspect of the present disclosure may provide an aircraft or an automobile, including the top coat composition, but is not limited thereto. In the method of applying the coating composition of the present application to a subject of an aircraft or an automobile, the surface of the subject is removed with a degreasing agent or the like, and the coating composition of the present application is introduced into an air blower. It can be applied to maintain a certain distance and then to coat the subject of the aircraft or automobile through drying, curing, etc., the composition of the present application in a variety of ways that can be easily selected by those skilled in the art The painting can be done by using, a detailed description thereof will be omitted.

In the detailed description of the method of manufacturing the topcoat composition, which is the second aspect of the present application, the description of the topcoat composition and the repetition of the topcoat composition will be omitted, and further detailed description will be provided through the supplementary description and examples in the following manufacturing method. do.

In the step of preparing the polyester main resin, more specifically, 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid while adding nitrogen to 140 ~ It is preferable to terminate the reaction at an acid value of 3.0 or less and Color 3 or less by maintaining the temperature by heating to 240 ° C., but the present invention is not limited thereto. Except for the description of the composition and repetitive matters of the top coat composition, each reaction temperature, acid value and color value are values that maximize the properties of the curing agent to be mixed with the polyester main resin, and the reaction temperature and acid value mentioned herein. And stirring and reaction other than the color value is a technical matter that can be repeatedly reproduced by those of ordinary skill in the art to which the present application belongs, and will not be described in detail, the following examples will be described in more detail through the following examples.

However, the scope of the present application is not limited to the following examples, and obviously includes modifications of equivalent technical spirit.

end) polyester Preparation of thematic resin

Neopentyl Glycol 41% (Weight), Adipic Acid 23% (Weight), Isophthalic Acid 22% (Weight) 140? It heated up continuously over 3 hours to -240 degrees, and hold | maintained reaction, the reaction was complete | finished under acid value 3.0 or less and Color 3 or less, and polyester main resin (HP1) was manufactured.

I) Preparation of Top Coating Composition and Specimen Preparation

The polyether main resin (HP1) 235g, titanium dioxide 265g, catalyst (dibutyltin dilaurate) 15g, additives (unsaturated polycarboxylic acid-based dispersant, bentonite-based precipitation inhibitor, acrylic vesicle, and polyacrylic 25g of leveling agent), diluent (5 to 7% methyl amyl ketone, 1 to 3% ethyl 3-ethoxy propionate, 5 to 7% methylpropyl ketone, 1 to 3% xylene, VOC regulation 300 g of exemplified dimethyl carbonate 0.1% to 0.5% of the exempt substance was sequentially added, followed by rapid stirring for 30 minutes, and dispersed to prepare a paint having a softening degree of 10 μm. 160 g of aliphatic polyisocyanate curing agent was added to the prepared paint, and the mixture was stirred for 30 minutes to prepare the composition, and then coated on the specified specimen with a spray according to the standard, and then dried and cured to obtain an aircraft surface coating film.

end) polyester Preparation of thematic resin

Neopentyl Glycol 36% (Weight ratio), Adipic Acid 23% (Weight ratio), Isophthalic Acid 22% (Weight ratio), Trimethylolpropane 5% (Weight ratio), while nitrogen was added to continuously increase the temperature over 140 hours to 240 ℃ over 3 hours, The reaction was terminated with an oil-fat reaction of acid value 3.0 or less and Color 3 or less, and polyester main resin (HP2) was produced.

I) Preparation of Top Coating Composition and Specimen Preparation

The polyether main resin (HP2) 235g, titanium dioxide 265g, catalyst (dibutyltin dilaurate) 15g, additives (unsaturated polycarboxylic acid-based dispersant, bentonite-based precipitation inhibitor, acrylic vesicle, and polyacrylic 25g of leveling agent), diluent (5 to 7% methyl amyl ketone, 1 to 3% ethyl 3-ethoxy propionate, 5 to 7% methylpropyl ketone, 1 to 3% xylene, VOC regulation 300 g of exemplified dimethyl carbonate 0.1% to 0.5% of the exempt substance was sequentially added, followed by rapid stirring for 30 minutes, and dispersed to prepare a paint having a softening degree of 10 μm. 160 g of aliphatic polyisocyanate curing agent was added to the prepared paint, and the mixture was stirred for 30 minutes to prepare the composition, and then coated on the specified specimen with a spray according to the standard, and then dried and cured to obtain an aircraft surface coating film.

< Comparative example 1>

end) polyester Preparation of thematic resin

Neopentyl Glycol 43% (Weight), Adipic Acid 23% (Weight), Isophthalic Acid 20% (Weight) while continuously raising the temperature from 140 ° C to 240 ° C over 3 hours, and maintaining the acid value below 3.0. The reaction was terminated under Color 3 to prepare a polyester main resin (HP3).

I) Preparation of Top Coating Composition and Specimen Preparation

235 g of the polyether-based resin (HP3), 265 g of titanium dioxide, 15 g of a catalyst (dibutyl tin dilaurate), an additive (unsaturated polycarboxylic acid-based dispersant, bentonite-based precipitation inhibitor, acrylic vesicle, and polyacryl-based 25g of leveling agent), diluent (5 to 7% methyl amyl ketone, 1 to 3% ethyl 3-ethoxy propionate, 5 to 7% methylpropyl ketone, 1 to 3% xylene, VOC regulation 300 g of exemplified dimethyl carbonate 0.1% to 0.5% of the exempt substance was sequentially added, followed by rapid stirring for 30 minutes, and dispersed to prepare a paint having a softening degree of 10 μm. 160 g of aliphatic polyisocyanate curing agent was added to the prepared paint, and the mixture was stirred for 30 minutes to prepare the composition, and then coated on the specified specimen with a spray according to the standard, and then dried and cured to obtain an aircraft surface coating film.

< Test Example >

The physical properties of the specimens prepared by Example 1 and Comparative Examples 1 and 2 were measured, which are shown in Tables 1 and 2 below.

Test composition table (unit g) Example 1 Example 2 Comparative Example 1 H P 1 235 H P 2 235 H P 3 235 Titanium dioxide 265 265 265 catalyst 15 15 15 additive 25 25 25 Dilute My 300 300 300 Aliphatic Polyisocyanate
Polymer (curing agent) 160 160 160 Total 1000 1000 1000

Experiment result Item Example 1 Example 2 Comparative Example 1 Drying time ○ ○ ○ Polish ○ ◎ □ Attached ○ ○ □ Flexibility ○ ◎ ○ Solvent resistance ○ ○ ○ Heat resistant ○ ○ ○ Low Temperature Flexibility ○ ◎ ○ V O C ○ ○ ○ Container state ○ ○ ○ Facilitated storage stability ○ ○ ○ My castle ○ ○ ○ Accelerated weathering ○ ○ ○ of mine Habit ○ ○ ○ Remover ○ ○ ○

Rating Grade-◎ Excellent ○ Good □ Normal △ Lack × Poor

-In case of Comparative Example 1, all the physical properties were excellent, but the gloss and the adhesion were inferior. However, in the case of Example 1 and Example 2, it was confirmed that all the items showed good physical properties.

Although the present invention has been described in detail with reference to the embodiments and examples, the present invention is not limited to the above embodiments, and may be modified in various forms, and is commonly used in the art within the technical spirit of the present invention. It is evident that many variations are possible by those of skill in the art.

Claims

With respect to 100 parts by weight of a polyester main resin having a hydroxyl value of 150 to 200 (mg KOH / g) and a viscosity of 1000 to 2000 (cps / 25 ° C),
Containing 50 to 70 parts by weight of an aliphatic polyisocyanate curing agent,
Topcoat composition.

The method of claim 1,
The polyester main resin is prepared by adding nitrogen to 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid,
Top coat composition.

The method of claim 1,
The aliphatic polyisocyanate curing agent is one or more selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate,
Top coat composition.

The method of claim 1,
The aliphatic polyisocyanate curing agent is based on 100% by weight of aliphatic polyisocyanate curing agent,
At least one selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate includes 60 to 70 wt%,
Top coat composition.

The method of claim 1,
To 100 parts by weight of the polyester main resin, titanium dioxide 75 to 125 parts by weight, 5 to 10 parts by weight of catalyst, 10 to 15 parts by weight of additives, and 125 to 175 parts by weight of a diluent,
Top coat composition.

S1) 35 to 42 parts by weight of neopentyl glycol, 15 to 30 parts by weight of adipic acid, and 20 to 25 parts by weight of isophthalic acid while maintaining the temperature by heating to 140-240 ° C. to prepare a polyester main resin step; And
S2) mixing 50 to 70 parts by weight of an aliphatic polyisocyanate curing agent based on 100 parts by weight of the prepared polyester main resin, comprising:
Method for producing a topcoat composition.

The method according to claim 6,
The aliphatic polyisocyanate curing agent is one or more selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate,
Method for producing a topcoat composition.

The method according to claim 6,
Preparation step of the aliphatic polyisocyanate curing agent, based on 100% by weight of aliphatic polyisocyanate curing agent,
At least one selected from the group consisting of hexamethylene diisocyanate, isobornyl diisocyanate, methylene diisocyanate, isophorone diisocyanate, and cyclohexyl diisocyanate is a step prepared by including 60 to 70% by weight,
Method for producing a topcoat composition.

The method according to claim 6,
After the step S2), adding 75 to 125 parts by weight of titanium dioxide, 5 to 10 parts by weight of catalyst, 10 to 15 parts by weight of additives, and 125 to 175 parts by weight of a diluent; further comprising,
Method for producing a topcoat composition.

A top coating composition according to any one of claims 1 to 9,
Aircraft or car.