KR100579795B1 - A paint composition of combination under-coating for anticorrosive pre-coated metal - Google Patents

Abstract

The present invention relates to an integrated coating composition for high corrosion resistance PCM (PCM), and more particularly, to a polyester modified epoxy resin hot blended with an epoxy resin and a prepolymer. And, by mixing additives such as dispersant and surface conditioner to form the bottom coating composition, it can be applied to PC M without limiting the type of steel sheet, application or top coat type, and especially the integrated coating material for PC which exhibits high corrosion resistance. It relates to a composition.

Description

A paint composition of combination under-coating for anticorrosive pre-coated metal

The present invention relates to an integrated coating composition for high corrosion resistance PCM (PCM), and more particularly, to a polyester modified epoxy resin hot blended with an epoxy resin and a prepolymer. And, by mixing additives such as dispersant and surface conditioner to form the bottom coating composition, it can be applied to PC M without limiting the type of steel sheet, application or top coat type, and especially the integrated coating material for PC which exhibits high corrosion resistance. It relates to a composition.

At present, the resin type of the PC paint for paint is widely used polyester, epoxy, polyester modified epoxy, epoxy modified polyester, acrylic resin and the like.

In general, steel sheets for PC (Pre-coated metal) are mainly used for home appliances and building exterior materials.

Among them, household appliances include home appliances, switchboards, and furniture for iron and the like. These require delicate processing, aesthetic appearance, and the like, and require a resin-type undercoat having excellent workability. Therefore, polyester resin, modified polyester, etc. which have a flexible resin skeleton are mainly used for the resin component of the undercoat composition applied to these.

However, under the above-mentioned polyester resin and modified polyester type undercoat, the corrosion resistance of the processed part is inferior, chemical resistance is inferior, and improvement of these physical properties is calculated | required.

On the other hand, PCM Hado for building exterior materials is applied to roofs, walls, shutters, etc. of buildings, and they are exposed to severe corrosive environments in the outdoors. Therefore, an epoxy resin, a modified epoxy resin, etc. which are excellent in corrosion resistance, chemical resistance, and adhesiveness are used.

However, in the case of such a paint coating composition, the glass transition temperature (Tg) of the paint coat is usually set too high to improve the corrosion resistance and adhesion in the coated steel sheet during processing. In these areas, corrosion easily proceeds. Therefore, as a building exterior material, the workability is required to minimize the cracks during processing, and to increase the adhesion of the material to minimize the corrosion in the crack portion.

In addition, it is a reality that different types of undercoats are used according to the type of steel sheet and the type of the upper coat, and since the kinds of the undercoat are about 20 types, many problems are raised as follows.

First, the loss of paint is large. In other words, since many kinds of sewers are supplied in small scales, there is a case in which excess paint is discarded due to paint exchange and line washing in the painting line, resulting in large economic losses.

Second, labor costs are high. In other words, it requires a lot of manpower and time required for many kinds of road management, frequent replacement of paints.

Third, due to frequent changes in the working conditions due to the production of small quantities of various varieties of paint, the skill of the worker tends to be lowered, so that the defective rate increases, and the work delay time due to the lot exchange increases.

Therefore, in order to solve the above problems, there is an urgent need for the development of integrated coatings for improving productivity when manufacturing the paint coating composition.

At present, many studies have been conducted on integrated coatings at home and abroad, and many of them have been commercialized, but the resin type of these coatings is mainly epoxy modified polyester or polyester modified epoxy resin. It is pointed out that there is a problem in corrosion resistance in the dragon, and there is also a problem that is unsatisfactory about the adhesion of the bottom to the top coat type or material type.

Therefore, in the present invention, after the long research to solve the problems appearing in the conventional integrated paint coating composition for PCM, the epoxy resin as a modified epoxy resin using a prepolymer (hot polymer) and hot blending (Hot Blending) is applied to the undercoat Regardless of the field, the top coat, or the type of material, the present inventors have found that the degree of integration can be achieved with desirable physical properties such as high corrosion resistance.

Accordingly, the present invention, unlike the prior art, by newly forming a polyester-modified epoxy resin composition by hot blending, the polyester-modified epoxy type PC exhibiting high corrosion resistance while maintaining the workability of the polyester type for various materials and top coats. The purpose is to provide an integrated coating composition for M.

The present invention is an integrated coating composition comprising a polyester-modified epoxy resin as a main component,

(1) 35 to 60% by weight of a polyester-modified epoxy resin obtained by hot blending 30 to 50% by weight of the epoxy resin and 5 to 10% by weight of the prepolymer containing a curing agent,

(2) 10 to 30% by weight of rust preventive pigments and extender pigments;

(3) 10 to 55% by weight of the solvent, and

(4) 0.1 to 3% by weight of additives containing acrylic and polyester dispersants and surface conditioners

It is characterized by an integrated coating composition for high corrosion resistance PCM containing.

Hereinafter, the present invention will be described in more detail.

Resin Used in the Invention The epoxy resin is a diglycidyl ether-based epoxy resin obtained from epichlorohydrin and bisphenol A, which are the most common forms. The number average molecular weight is 3,000 to 10,000, and the glass transition temperature is -5 to. Resin whose 80 degreeC and OH equivalent weight (%) 300-500% can be used suitably.

Commercially available products of the epoxy resin include YD014, YD017, YD019, YD128 (above, Kukdo Chemical Co., Ltd.), EPIKOTE 1004, EPIKOTE 1007, EPIKOTE 1009 (above, manufactured by Shell), N8040, N8070, N8090 (above, Korea Chemical Co., Ltd.) Etc. can be mentioned. One or more of these can be selected and used suitably, Preferably, N8040 and N8070 are suitable.

The prepolymer which is hot blended with such an epoxy resin is a resin solution obtained by reacting a polyol and a blocked diisocyanate. The number average molecular weight is 500 to 1,000, and the NCO equivalent value (%) of 500 to 700% is preferably used. Can be.

As the polyol used herein, an ether type or an ester type diol is suitably used. The main monomers of the polyol include diols such as ethylene glycol, propylene glycol, diethylene glycol, and neotenyl glycol, maleic anhydride, phthalic anhydride, and isophthalic acid. And dibasic acids such as terephthalic acid, tetrahydrophthalic anhydride, methylhydrophthalic anhydride, adipic acid, heptic acid and sebacic acid, and can be suitably used by reacting one or two or more of the diols and dibasic acids.

Alternatively, many polyols produced using these diols and dibasic acids are commercially available, and these may be selected. These commercially available products include Poly THF 250, Poly THF 650, Poly THF 1000, Poly THF 1800 (above BASF), Tone M-100, Tone M-201, Tone 0201 (above Union Carbide), CAPA 200 , CAPA 210, CAPA 212, CAPA 213 (above, SOLVEY products) and the like, and one or more of them can be selected and used appropriately.

The diisocyanate is toluene diisocyanate (TDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), 4,4-diphenylmethane diisocyanate (MDI), xylene diisocyanate (XDI), 1,5 -Naphthalene diisocyanate (NDI), lysine diisocyanate (LDI), and the like, and one of them can be selected.

Commercially available products of blocked diisocyanate include Desmodur L, Desmodur IL, Desmodur HL, Desmodur BL3175, Desmodur E3265 (above, Bayer), LUXATE (Olin), and the like. .

As the block agent, a block agent having a dissociation temperature in the range of 120 to 180 ° C. is suitable, and if it is below this range, storage stability is lowered such that the molecular weight increases due to the dissociation of the block agent during long-term heat storage. When it is more than the said range, hardening does not fully advance but hardened | cured material property and corrosion resistance fall. As the blocking agent, oximes, phenols, lactams, alcohols and the like can be suitably used.

According to the present invention, a polyester-modified epoxy resin, which is a mixed resin obtained by hot blending the epoxy resin and the prepolymer, may be controlled in the paint manufacturing process. The mixing ratio is controlled by the equivalent ratio of the OH group of the epoxy resin and the NCO group of the prepolymer. The OH / NCO equivalent ratio of 1.0 / 0.2 ~ 1.0 / 1.0 is suitable, when the OH / NCO equivalent ratio is less than 1.0 / 0.2 is formed a low cross-link density, the corrosion resistance and boiling water resistance is lowered, on the contrary too high if exceeding 1.0 / 1.0 Crosslinking density may be formed, causing deterioration of adhesion and processability. In addition, such a mixed resin solution may be used a catalyst for improving the curing accelerator, it is preferable to use an alkaline catalyst when selecting the catalyst. As for the usage-amount of the said catalyst, 0.001 to 0.01 weight% of a mixed resin solution is suitable, and when it uses more, there exists a possibility of the storage stability falling.

As such, the mixed resin obtained by hot blending the epoxy resin and the prepolymer has a relatively homogeneous hard segment of the epoxy resin and a flexible segment of the polyester polyol (FLEXIBLE SEGMENT) in the coating film. It is advantageous to exhibit optimal coating properties by being formulated.

In the present invention, the mixed resin is a polyester-modified epoxy resin which is a main component of the paint, and is preferably used in an amount of 35 to 60% by weight based on the total paint composition.

In the present invention, chromic acid pigments and non-chromic acid pigments may be used as the rust preventive pigments among the pigment components.

As the chromic acid pigment, strontium chromium, calcium chromium, barium chromium, zinc chromium potassium, zinc tetrachloride, etc. may be used. As the non-chromic acid pigment, zinc phosphate, organic nitro compound zinc salt, calcium silicate, zinc potassium, or the like may be used. It may be used, and one or two or more thereof may be mixed.

The rust preventive pigment may be used in 5 to 10% by weight of the total paint weight, when the blending amount of the rust preventive pigment is less than 5% by weight is not enough corrosion resistance, when it exceeds 10% by weight, the boiling resistance and processability of the coating film is lowered Can be.

In particular, it is effective to use a large amount of chromium-based pigments in harsh corrosive environments, and non-toxic pigments such as calcium silica can be used when toxic substances are restricted. In some cases, a mixture of chromium-based pigments and non-chromium pigments can be used. Can be.

In addition to the rust preventive pigments, extender pigments such as silica, mica, alumina, talc and the like may also be used in 5 to 20% by weight of the total paint weight. In addition, a sedimentation inhibitor, a pigment dispersant, etc. can be mix | blended as needed.

As the organic solvent of the present invention, one or two or more kinds of hydrocarbons, esters, and ketones may be mixed and blended within the range of 10 to 55% by weight in the total paint composition, and alcohols may be added for storage stability. It can be mix | blended in 0.1 to 0.5% of coating amount. The alcohols may be primary alcohols, secondary alcohols and tertiary alcohols, and pigment precipitation may occur when blended with 0.5% or more.

The coating material to be applied by applying the coating composition of the present invention composed by properly mixing the components according to the present invention as described above, such as cold rolled steel sheet (CR), hot-dip galvanized steel sheet (GI), electro-galvanized steel sheet (EGI), Metal plates such as aluminum zinc alloy plated steel sheets (G / L) are suitable, and exhibit a certain physical property in each metal material due to the preferred composition of the paint.

The coating method can be roll coating, curtain coating, immersion coating and spray coating, which is very effective for high speed roll coating. In the case of roll coating, it can be coated by a coating method (reverse coating, natural coating) by two rolls or by a coating method by three rolls, and a dry thickness of the coating film is usually 4 to 6 μm, and this range is appropriate. The best corrosion resistance and workability can be achieved. If the dry thickness of the coating film is too thin, the corrosion resistance is reduced, while if too thick, the workability may be adversely affected.

When the coating composition of the present invention is applied as described above, the coating material needs surface treatment to improve adhesion and corrosion resistance of the coating film, and should remove contaminants such as oil and dust. At this time, the surface treatment material is a phosphate-based, chromate-based, chromic acid-based, etc., the surface treatment method is a reactive and coating surface treatment method.

When applying the paint composition according to the present invention, it is possible to apply a top coat such as polyester paint, silicone modified polyester paint, fluorine paint, and the like and can be cured under conditions suitable for the respective paints.

In the present invention, the curing conditions of the coating composition is the maximum material delivery temperature (PMT) is 199 ~ 254 ℃ and the curing time is usually suitable 20 ~ 60 seconds. Below the maximum temperature range of the material delivery, the adhesion between the material and the roadway may be deteriorated, which may be inferior in corrosion resistance and boiling water resistance. Above that, the adhesion of the roadway and the topway may be degraded, resulting in poor workability and impact resistance. have.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples.

Example 1

(A) Mixing resin solution of epoxy resin solution and prepolymer (hereinafter referred to as "mixing resin 1", Korea Chemicals, solid content 50% by weight, number average molecular weight 3,000 ~ 10,000, glass transition temperature -5 ~ 80 ℃) 10% by weight , 8 wt% of organic solvent Cocosol # 100 (Yonggong Co., Ltd.), 8 wt% of cyclohexanone [Eastman], and 0.1 wt% of BYK P-104 [BYK Chemie] as a dispersant were added to a tin can and stirred sufficiently.

(B) Then, while stirring, 5.8 wt% of strontium chromate [MCS], an rust preventive pigment, was gradually added thereto, followed by stirring, and in the same manner, 6.6 wt% of TIPAQUE CR-95 [Ishihara] and a barium sulfate [Smithko] 8.3 wt% , 0.3 wt% of a sedimentation inhibitor [Aerosil 200, Deggusa] was added sequentially, followed by fully stirring.

(C) After stirring, glass beads having a diameter of 2 to 3 mm were added thereto, and the mixture was sufficiently dispersed for 2 to 3 hours using a shake type disperser.

(D) After dispersing, the particle size was measured using a grind gauge and finished when the particle size was 5 μm or less.

(E) 47.5% by weight of the mixed resin 1 was added again, followed by stirring.

(F) 0.5% by weight of a mixed additive [URAD DD-27, 60% of solid content] and 0.2% by weight of a curing accelerator catalyst [STAN BL, Kolon Emulsion Co., Ltd.] to 1.8% by weight of organic solvent Cellosolve Acetate (Union Carbide) After mixing, the mixture was slowly added to the tin can under stirring.

(G) After sufficient stirring, the glass beads and impurities in the tin can were filtered using a 150 mesh network.

(H) Adjust the paint viscosity to about 60 to 80 seconds (pot cups # 4, 25 ° C) using a mixed solvent [0.85% by weight of cellosolve acetate, 1.1% by weight of cyclohexanone, 1.1% by weight of cocosol # 100]. To obtain a coating composition.

Example 2

Strontium chromate as an anti-corrosive pigment of Example 1 (b) was replaced with a non-toxic pigment calcium silica [Shieldex, GRACE Davison], and 0.3 wt% of an anti-settling agent [Aerosil 200] was 0.5 wt% of siloid ED3 [GRACE Davison]. % Was prepared in the same manner as in Example 1, except that 0.1 wt% of BYK P-104 as a catalyst was replaced by the same amount in SOLSPERSE 24000 [ZENECA].

Example 3

Except that the same amount of mixed resin 1 of Example 1 was replaced by mixed resin 2 [Korea Chemicals, 50% by weight of solid content, number average molecular weight 5,000 ~ 15,000, glass transition temperature -5 ~ 80 ℃] of Example 1 It prepared in the same manner as the preparation method.

Example 4

It was prepared in the same manner as in Preparation Example 2, except that Mixing Resin 1 of Example 2 was replaced by the same amount as Mixing Resin 2.

Comparative Example 1

(A) 10% by weight of SKA-955 [line diameter, polyester resin solution, 50% solids], 7% by weight of Cocozol # 100, 7% by weight of cyclohexanone, and 0.1% by weight of BYK P-104 into the tin can. Stirred.

(B) Subsequently, 5.8% by weight of strontium chromate is slowly added while stirring, and then 6.6% by weight of TIPAQUE CR-95, 8.3% by weight of barium sulfate, and 0.3% by weight of aerosil-200 are added again in the same manner. Stir enough.

(C) After stirring, glass beads having a diameter of 2 to 3 mm were added thereto, and the mixture was sufficiently dispersed for 2 to 3 hours using a shake type disperser.

(D) After dispersing, the particle size was measured using a grind gauge and finished when the particle size was 5 μm or less.

(E) After adding and stirring 3% by weight of SKA-955 and 1% by weight of cellosolve acetate, the mixture was stabilized at room temperature for 1 to 2 hours.

(E) 13% by weight of SKA-955, 26% by weight of epoxy resin [R8040, Koryo Chemical], 4% by weight of hardener [DESMODUR BL3175, BAYER], 0.5% by weight of mixed additive [URAD DD-27, 60% of solid content] 0.2% by weight of accelerated catalyst [STAN BL] was mixed with 1.8% by weight of cellosolve acetate, and then slowly charged into a stirring tin can.

(G) After sufficient stirring, the glass beads and impurities in the tin can were filtered using a 150 mesh network.

(H) The coating composition was adjusted so that paint viscosity might be about 50 to 60 second (pot cup # 4, 25 degreeC) using the mixed solvent [2.7 weight% of cyclohexanone, 2.7 weight% of cocosol # 100].

Comparative Example 2

(A) 15% by weight of SKA-955 [line diameter, polyester resin, 50% of solid content], 7% by weight of Cocosol # 100, 6% by weight of ESTASOL [Eastman], 4% by weight of cellosolve acetate, butyl cellosolve [Union Carbide] 2 wt% was added to a tin can and stirred, and 0.1 wt% of KEN-REACT KA489 and 0.1 wt% of Cosol sol 100 were added to the tin can and sufficiently stirred.

(B) Subsequently, 6 wt% of silica [aluminum silicate ASP-200] was gradually added while stirring, followed by stirring, followed by 20 wt% of strontium chromate and 2 wt% of BENTON 38 PASTE [solid content of 10%] in the same manner. It was stirred again sufficiently.

(C) After stirring, glass beads having a diameter of 2 to 3 mm were added thereto, and the mixture was sufficiently dispersed for 2 to 3 hours using a shake type disperser.

(D) After dispersing, the particle size was measured using a grind gauge and finished when the particle size was 10 μm or less.

(E) 8 wt% of SKA-955 and 1 wt% of Cocosol # 100 were added and stirred, and then stabilized at room temperature for 1 to 2 hours.

(E) 16.4% by weight of SKA-955 and 4.93% by weight of CYMEL 303 [melamine curing agent], V8013 [Epoxy resin solution, solid content 50%, Koryo Chemicals] 2.8% by weight, V5901 [Mixed additives, 1.6% solution of acrylic resin, Koryo Chemical 0.2% by weight was slowly added to the stirring tin can.

(G) After stirring, 0.45% by weight of an acid catalyst, NACURE 155 [KING, 50% solids], was added to a stirring tin can.

(H) After sufficient stirring, the glass beads and impurities in the tin can were filtered using a 150 mesh network.

(I) Mixing solvent [mixing solvent of cocosol # 100 and cellosolve acetate] Add an appropriate amount (about 3.82% by weight) and adjust the paint viscosity so that the paint viscosity is about 80 to 100 seconds (pot cup # 4, 25 ° C). A composition was obtained.

Experimental Example

The paint compositions of Examples 1 to 4 and Comparative Examples 1 to 2 are shown in Table 1 below, and physical properties of Examples 1 to 4 and Comparative Examples 1 to 2 are shown in Tables 2 to 5 below.

Table 2 shows the polyester type top coat on the hot dip galvanized steel sheet, Table 3 shows the polyester type top coat on the aluminum zinc alloy coated steel sheet, Table 4 shows the fluorine top coat on the hot dip galvanized steel sheet, and Table 5 shows the aluminum zinc alloy plated Physical properties obtained from coated specimens obtained by coating fluorine top coat on steel sheet.

[Film Property Test and Evaluation Method]

Each coating composition obtained in the above Examples and Comparative Examples was dried on a hot dip galvanized steel sheet having a thickness of 0.45 mm and a chromate treated aluminum zinc alloy coated steel sheet having a thickness of 4 to 6 µm. It was painted with a bar coater as much as possible, and baked and cured so that the maximum temperature reached to the material was 210 to 216 ° C. FJ2610-Y006 (1000) [Polyester Topology, Korea Chemical] and YJ2442-E001 [Fluorine Topology, Korea Chemical] are coated on the paint undercoat so that the dry film thickness is 15 and 20 μm, respectively, using a bar coater to reach the material. It baked and hardened | cured so that the maximum temperature might be 224-232 degreeC and 249-254 degreeC, respectively. Various coating film physical property tests were performed using this coating plate.

(A) MEK resistance: The surface of the said coating plate was laminated | stacked 4 sheets of gauze impregnated with methyl ethyl ketone, and reciprocated between about 5 cm in length by the pressure of 4 kg / cm <2> of pressure. The number of round trips until the bottom coat was visible was recorded. More than 50 round trips are indicated by 50 ↑.

(B) Workability: The T value at which the coating surface was bent at 180 ° with a vise at a room temperature of 20 ° C at the outside to prevent cracking in the bent portion was indicated.

0T: Bending without inserting anything inside the paint plate

1T: Bending a plate of the same thickness inside the paint plate

2T: Bending two plates of the same thickness inside the paint plate

3T: Bending 3 sheets of the same thickness inside the paint plate

(C) Chemical resistance: After a spot test of the 0.5% NaOH solution and the 0.5% HCl solution at 25 ° C. for 48 hours, the spots were washed and evaluated according to the following criteria.

◎: no change before test, ○: slight bubble is generated,

(Triangle | delta): Bubble generate | occur | produces considerably, x: The coating film peels and a raw material is seen.

(D) Impact resistance: Put the paint plate on the Dupont Tester so that the paint surface faces downward, and drop the weight of 500g whose curvature is 1 / 2Φ from 50cm height. The convex portions of the coated specimens formed by dropping were observed, and a taping test was performed as follows.

(Double-circle): A crack does not generate | occur | produce and a coating film does not peel off by taping.

(Circle): Fine crack generate | occur | produces, but a coating film is not peeled off by taping.

(Triangle | delta): A considerable crack generate | occur | produces and gambling peels off by taping.

X: A coating film peels by an impact.

(E) Boiling water: The coating plate was immersed in boiled deionized water at about 100 DEG C for 4 hours, and then pulled up to evaluate the drawing state.

◎: no change, ○: slight bubbles are generated

(Triangle | delta): Bubble generate | occur | produces considerably and x: Bubble arises remarkably on the whole surface.

(F) Saline water resistance: After the coating plate was cut to a size of 70 mm in width and 150 mm in length, a paint surface was drawn in a "x" shape using a knife or the like so that a 50 mm portion of the vertical edge was centered. After the 2T process part was formed in the lower end, the side edge was sealed using 1 inch Scotch tape. The "×" part (CC part, Cross Cut) in the coating plate thus obtained was evaluated according to ASTM B117, the cut edge (Edge part) was evaluated by the bubble erosion distance, and the 2T processing part was evaluated according to the following evaluation criteria. Evaluated.

◎: No generation of rust or bubbles. (Circle): White rust and a little bubble generate | occur | produce.

(Triangle | delta): White rust generate | occur | produces considerably and a little bubble also generate | occur | produces.

X: Generation | occurrence | production of white rust and foam | bubble generate | occur | produces considerably.

(G) Coating workability: Roll coating (reverse coating) was performed about the coating composition of each Example adjusted to viscosity of about 70 to 80 second (pod cup # 4, 25 degreeC). The coating surface was coated at a thickness of 5 to 10 µm under the condition of a backup roll speed of 90 m / min, and the coating surface was observed and evaluated.

(Double-circle): Desired coating film thickness is obtained and a coating surface is uniform.

(Circle): The desired coating film thickness is obtained, but a roll trace generate | occur | produces a little.

X: Coating film thickness is nonuniform and a trace of a roll arises remarkably.

The paint compositions used in the following Table 1 are as follows.

Aluminum silicate ASP200 (ENGELHARD): extender pigment

SYLOID ED3 (GRACE DAVISON): matting agent

AEROSIL 200 (DEGGUSA): Sedimentation inhibitor

SOLSPERSE 24000 (ZENECA): Dispersant

BYK P-104 (BYK CHEMIE): Dispersant

STAN BL (Kolon Oil Painting): Curing catalyst

URAD DD-27 60% SOLN (DSM): Mixed additive

V5901 (Korea Chemical): Mixed additive

BENTON PASTE 10% (NL CHEMICAL company)

KEN-REACT KA 489 (KENRICH): Dispersant

NACURE 155 50% (KING INDUSTRIES): Acid catalyst

TABLE 1

1) Mixed resin 1: V8018 [Korea Chemical, 50% solids epoxy resin] / Tone 0201 [Union Cabide product, polyol, number average molecular weight 560] / HMDI / MEK OXIME mixed resin

2) Mixed resin 2: Mixed resin composed of V8018 [Korea Chemical, 50% solids epoxy resin] / Poly THF 1000 [BASF] / TDI / MEK OXIME organic solvent

TABLE 2

TABLE 3

TABLE 4

TABLE 5

As described above, the present invention, unlike the prior art by mixing an epoxy resin and a pre-polymer-polyester modified epoxy resin by mixing additives such as rust preventive pigments, sieving pigments and solvents, dispersants and surface conditioners to form a paint coating composition It has an effect that can be effectively applied to the PC CM while exhibiting high corrosion resistance without limiting the type or use of steel sheet or the top coat type.

Claims (3)

In an integrated paint coating composition composed mainly of a polyester-modified epoxy resin, (1) A prepolymer 5 having a number average molecular weight of 500 to 1,000 and an NCO equivalent value of 500 to 700% as a resin solution obtained by reacting 30 to 50% by weight of epoxy resin with polyol and blocked diisocyanate with respect to the whole composition. ~ 10% by weight of the polyester-modified epoxy resin 35-60% by weight of the OH / NCO equivalent ratio of 1.0 / 0.2 to 1.0 / 1.0 of the OH group of the epoxy resin and the NCO group of the polypolymer mixed (2) 10 to 30% by weight of rust preventive pigments and extender pigments; (3) 10 to 55% by weight of the solvent, and (4) 0.1 to 3% by weight of additives containing acrylic and polyester dispersants and surface conditioners Integrated coating composition for high corrosion resistance PCM comprising a. According to claim 1, wherein the epoxy resin is a diglycidyl ether-based epoxy resin obtained from epichlorohydrin and bisphenol A, the number average molecular weight is 3,000 ~ 10,000, the glass transition temperature is -5 ~ 80 ℃, OH equivalent ( %) Is a resin of 300 to 500%, the highly integrated corrosion-resistant paint composition for PCM. According to claim 1, wherein the anti-corrosive pigment is used 5 to 10% by weight of the total paint weight, sieving pigment is a coating material composition for high corrosion resistance PCM, characterized in that used for 5 to 20% by weight of the total paint weight.