KR101029489B1 - One component type polyurethane paint composition forming thickness film - Google Patents

Abstract

The present invention provides a thick film one-component polyurethane resin composition comprising an inorganic pigment, other additives, and a high boiling point thinner to a mixed resin of a polyester polyol resin, a block polyisocyanate resin, and a polyurethane resin, and the same. The present invention relates to a coating composition, having excellent workability for thick film operation, and having excellent physical properties such as water resistance, corrosion resistance, weather resistance, processability and impact resistance, and having properties equivalent to those of conventional products. It is possible to paint and produce a wide range of coiled steel sheets for interior and exterior construction, thus creating new demand.

Thick film, one component type, polyurethane resin, coating composition, one component type, polyester polyol, isocyanate

Description

Thick film one-component polyurethane coating composition {One component type polyurethane paint composition forming thickness film}

The present invention relates to a thick coating film, one-component polyurethane coating composition, and more particularly, by adding inorganic pigments, other additives and high boiling point thinner to a mixed resin of polyester polyol resin, block polyisocyanate resin and polyurethane resin It is made of a thick coating film, one-component polyurethane resin paint characterized by excellent physical properties such as water resistance, corrosion resistance, weather resistance, workability and impact resistance with excellent workability for high temperature and thick film (30 ~ 60 ㎛ thick film) work It relates to a composition.

In general, there is a technical limitation in forming a thick film of 20 μm or more with a single coating in a conventional roll coat painting work. Since it should be carried out, there was a problem in that the productivity was lowered and the workability and gloss stability due to excessive curing during excessive consumption of energy and repeated coating were inferior.

The prior art has a problem that appearance defects such as popping and bubbles occur in the coating film during the after-paint coating work to form a thickness of 30 ㎛ or more. Therefore, anti-papping agent is used to prevent the boiling of the coating film, which affects the curability of the coating film, thereby lowering the physical properties of the coating film, and there is a limitation in appearance improvement, which makes it impossible to work with the thick film.

Therefore, the present inventors have developed a thick-film one-component polyurethane resin composition as a result of research to solve the problem that the conventional coating composition has excellent weather resistance, workability, impact properties, but can not escape the limitation of the thin film. The invention was completed.

The present invention for solving the above problems is to prepare a mixed resin exhibiting efficient workability and excellent weather resistance and mechanical properties by mixing polyester polyol resin, block polyisocyanate resin and polyurethane resin, and inorganic pigments, other additives And by adding a high boiling point thinner to produce a paint, it is possible to work 30 ~ 60 ㎛ thick film in one coating, and has excellent workability, and also has excellent physical properties such as water resistance, corrosion resistance, weather resistance, workability and impact resistance. An object of the present invention is to provide a thick coating film, one component polyurethane coating composition characterized in that.

Conventional polyurethane paint has a limitation in painting work due to boiling phenomenon of coating film in coil coating line during post-painting work by one-time painting. To overcome this problem, coil coating line is repeated twice for high-quality building exterior coating. As the coating work is carried out, it is unproductive, resulting in a decrease in the coating properties due to the curing of the repeated coating.

The present invention for achieving the above object in the polyurethane coating composition,
Per 100 parts by weight of the coating composition,
Iii) polyester polyol resins and blocked polyisocyanate resins and polyurethanes
50 to 72.5 parts by weight as a mixed resin of the resin,
Ii) 0.1 to 17 parts by weight of an inorganic color pigment,
Iii) 23.0 to 30.5 parts by weight of a mixed solvent,
Iii) 1.2 to 1.9 parts by weight of an antifoaming agent,
Iii) 0.2 to 0.5 parts by weight of a curing accelerator,
Viii) 0.1 to 0.8 parts by weight of a polymer type wet dispersion agent,
The mixed resin is mixed with 30 to 41.5 parts by weight of polyester polyol resin, 18 to 27.7 parts by weight of block polyisocyanate resin and 2.0 to 3.3 parts by weight of polyurethane based on 100 parts by weight of the coating composition,
The polyester polyol resin is mixed with 21 to 30.5 parts by weight of polyester polyol having a weight average molecular weight of 1,500 or less and 9 to 11 parts by weight of polyester polyol having a weight average molecular weight of 5,000 or less, based on 100 parts by weight of the coating composition,
The block polyisocyanate is selected from one or more selected from the group consisting of fluorene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate or a trimer type isocyanate, and is used as methyl ethyl ketosim, dimethyl presol or A thick film one-component polyurethane coating composition characterized in that it is synthesized using a blocking agent in which methyl ethyl ketosim and caprolactam are mixed is used as a means for solving the problem.

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The present invention by means of the above-mentioned problem solving means is 30-60 ㎛ coating and twice painting that require only one coating to meet the coating film thickness of the thick-film steel sheet by operating the line twice in a conventional coil coater (Coil coater) 60 ~ 120 ㎛ thick film can be applied to save energy of coil coater and meet customer's demands for productivity and thick film demand. It is possible to create a wide range of interior and exterior coil steel sheets by coating a variety of thick film thicknesses, thereby creating new demand.

Hereinafter, in the description of the thick film one-component polyurethane coating composition according to the present invention for achieving the above effect, the conventional configuration in the art of the art is a part that can be easily understood by those skilled in the art, The description is omitted or briefly explained.

The present invention is a polyurethane coating composition,

Per 100 parts by weight of the coating composition,

Iii) 50 to 72.5 parts by weight of a mixed resin of a polyester polyol resin, a block polyisocyanate resin and a polyurethane resin,

Ii) 0.1 to 17 parts by weight of an inorganic color pigment,

Iii) 23.0 to 30.5 parts by weight of a mixed solvent,

Iii) 1.2 to 1.9 parts by weight of an antifoaming agent,

Iii) 0.2 to 0.5 parts by weight of a curing accelerator,

Iii) 0.1 to 0.8 parts by weight of a polymer type wet dispersion agent,

It relates to a thick coating film, one-component polyurethane coating composition characterized in that it contains.

Referring to the thick film one-component polyurethane coating composition of the present invention having the configuration as described above in more detail as follows.

The mixed resin in the present invention is characterized by mixing 30 to 41.5 parts by weight of polyester polyol resin, 18 to 27.7 parts by weight of block polyisocyanate resin and 2 to 3.3 parts by weight of polyurethane resin based on 100 parts by weight of the coating composition.

The said polyester polyol resin is for hardening reaction with block polyisocyanate, and when the mixing amount of polyester polyol resin becomes less than 30 weight part, there exists a possibility that the workability of the coating film by overcuring may fall, and it exceeds 41.5 weight part In this case, solvent resistance may decrease due to uncured coating film.

In addition, the block polyisocyanate resin is used for the curing reaction with the polyester polyol resin. When the amount of the block polyisocyanate resin is less than 18 parts by weight, the chemical resistance may decrease and the coating film hardness may decrease. When exceeding a weight part, there exists a possibility that the storage stability of a paint may fall, alkali resistance, and acid resistance may fall.

In addition, the polyurethane resin is to give the thixotropic and thixotropic property of the paint to increase the ascending properties of the coating during the coating work using a roll coater, the amount of the polyurethane resin is less than 2 parts by weight In the case of working, there is a possibility that the dome coating film riseability may decrease during operation, and when it exceeds 3.3 parts by weight, the coating film leveling property may decrease after coating due to the lack of fluidity.

And the polyester polyol resin used by this invention is 21 to 30.5 weight part of polyester polyols (hereinafter called polyol 1 ') with a weight average molecular weight of 1,500 or less with respect to 100 weight part of coating compositions, and a weight average molecular weight is 5,000 or less It is preferable to mix 9-11 weight part of polyester polyol (henceforth "polyol 2").

The polyol 1 has the flexibility characteristics of the coating film, and if the mixing is less than the range defined above, the flexibility of the coating film may be lowered, and when mixed over the range defined above, the hardness of the coating film may decrease. There is concern. Polyol 1 usable in the present invention is composed of polyols having a weight average molecular weight of 1,500 or less, including neopentyl glycol, trimethinol protane, adipic acid, fumaric acid and maleic anhydride.

In addition, the polyol 2 has the properties of hardness and adhesion of the coating film, and if mixed below the range defined above, there is a fear that the adhesion between the coating film and the hardness decreases. The workability of a coating film may fall. Polyol 2 usable in the present invention is composed of a polyol having a weight average molecular weight of 5,000 or less, including trimethyl pentanediol, neopentyl glycol, adipic acid, diethanolamine

And the isocyanate compounds usable in the resin synthesis of the block polyisocyanate functional group underlying in the thick film one-component polyurethane coating composition according to the present invention are selected from the group consisting of It is preferable to select and synthesize | combine 1 or more types from the group which consists of isocyanates.

Among isocyanate compounds listed above, isophorone diisocyanate, hexamethylene diisocyanate or their trimer type is used to prevent discoloration of the coating film during storage at room temperature or at low temperature during curing, and methyl ethyl ketosim as blocking agent. It is preferable to synthesize block polyisocyanate using a blocking agent in which dimethyl presol or methyl ethyl ketosim and caprolactam are mixed.

In addition, the pigment usable in the present invention uses calcined ceramic-based pigments having excellent chemical resistance and weather resistance, and examples thereof include titanium dioxide, magnesium, nickel, cobalt, chromium, antimony, zinc, copper, aluminate, and iron. It is preferable to use at least one of the mixed pigments in the selected.

In addition, the solvent that can be used in the present invention is a hydrocarbon solvent, xylene, Cocosol # 100 (Kocosol # 100, SK company name), Cocosol # 150 (Kocosol # 150, SK company name) and ester solvents as cellosolve Acetate, ethylene glycol diacetate, butyl cellosolve, glycol ether solvents include ethylene glycol mono methyl ether, ethylene glycol mono ethyl ether, ethylene glycol mono butyl ether, ethylene glycol mono ethyl ether acetate, dipropylene glycol methyl ether and alcohol As a system solvent, it is preferable to select and use 1 type or more from the group which consists of isopropyl alcohol and butyl carbitol.

In addition, the antifoaming agent is to suppress the generation of bubbles in the paint or the coating film, and uses a non-silicone type polyacrylate, and a polyacrylate and a polypropylene flow agent for the flow (flowability) of the coating film and Consisting of a polypropylene wax mixed additive, if the mixing amount of the antifoaming agent is mixed in less than the range defined above, there is a fear that bubbles are frequently generated in the paint or paint during the film production due to the lack of the mixing amount, If the amount of mixing exceeds the range defined above, no bubbles are generated in the paint or the coating film, but there is a concern that other physical properties of the paint may be lowered.

In addition, the curing accelerator is added to cure the thick film formed after the painting, and when the amount of the curing accelerator is less than the range defined above, the thick film may not be cured properly, and may exceed the range defined above. In this case, the inside of the thick film may not be cured properly while being cured from the surface of the thick film by rapid curing. Catalysts for the curing accelerator usable in the present invention is dibutyl tin dilaurate, dimethyl ethanolamine, ethylenediamine, dimethyluralamine, triethylenediamine, tetramethyl ethylenediamine, triethyleneamine, dimethylbenzylamine in the group consisting of 1 The species or more can be selected and used.

In addition, the wet dispersant is intended to improve the dispersibility of the pigment in the production of the paint, when the mixing amount of the wet dispersant is less than the range defined above, there is a fear that the dispersibility and shelf life is not good, and exceeds the range defined above In this case, the chemical resistance may not be good. Wetting and dispersing agents usable in the present invention may be used by selecting one or more from the group consisting of unsaturated polycarboxylic acid polymers, alkylolammonium salts of block copolymers, modified polyacrylates.

The thick film one-component polyurethane coating composition prepared by the above-described formulation is applied to the building exterior material, which is superior in productivity and workability compared to the conventional urethane resin coating to enable one-time coating during the work of the coil coating line, thereby saving energy. It is characterized by that can be obtained.

Hereinafter, the present invention will be described in detail with reference to the following examples. However, the embodiments of the present invention do not necessarily limit the scope of the present invention.

1. Preparation of thick film one-component polyurethane coating composition

The thick film one-component polyurethane coating composition was prepared using the compounds of the components as described in Table 1 below.

(Example 1)

The components of 1 to 8 in Table 1 below were sequentially added to separate containers, stirred well, and then dispersed to a particle size of 10 μm or less using a disperser to prepare dispersion 1, and 9 to other separate containers. Dispersion 2 was prepared by sequentially adding the components of 14 and performing medium speed stirring.

After mixing the dispersion 1 and the dispersion 2 prepared by the above method well, 15, 16, and 17 were added sequentially, and then the medium-speed stirring was sufficiently performed at a speed of 1,000 rpm to prepare a thick-film monocomponent polyurethane coating composition. It was.

(Example 2)

The components of 1 to 8 in Table 1 below were sequentially added to separate containers, stirred well, and then dispersed to a particle size of 10 μm or less using a disperser to prepare dispersion 1, and 9 to other separate containers. Dispersion 2 was prepared by sequentially adding the components of 14 and performing medium speed stirring.

Then, after mixing the dispersion 1 and the dispersion 2 prepared by the above method well, the components of 15, 16, 17 were sequentially added, and then the thick film one-component polyurethane coating composition was prepared in the same manner as in Example 1. It was.

(Example 3)

The components of 1 to 8 in Table 1 below were sequentially added to separate containers, followed by sufficient medium-speed stirring to prepare a dispersion 1, and a mixture of 16 and 17 solvents was added to another separate container, followed by 10 to 15 Dispersion 2 was prepared by incorporating the ingredients slowly with stirring.

And after mixing the dispersion liquid 1 and the dispersion liquid 2 prepared by the said method well, medium-speed stirring was fully performed at the speed of 1,000 rpm, and the thick-film one-component polyurethane coating composition was manufactured.

(Comparative Example 1)

The components of 1 to 8 in Table 1 below were sequentially added to separate containers, stirred well, and then dispersed to a particle size of 10 μm or less using a disperser to prepare dispersion 1, and 9 to other separate containers. Dispersion 2 was prepared by sequentially adding the components of 14 and performing medium speed stirring.

And after disperse | distributing the dispersion liquid 1 and the dispersion liquid 2 which were manufactured by the said method well, the thick-film one-component polyurethane coating composition was manufactured by the same method as Example 1.

(Comparative Example 2)

The components of 1 to 8 in Table 1 below were sequentially added to separate containers, stirred well, and then dispersed to a particle size of 10 μm or less using a disperser to prepare a dispersion 1, and 9 to other separate containers. Dispersion 2 was prepared by sequentially adding the components of 14 and performing medium stirring.

And after disperse | distributing the dispersion liquid 1 and the dispersion liquid 2 which were manufactured by the said method well, the thick-film one-component polyurethane coating composition was manufactured by the same method as Example 1.

(Comparative Example 3)

The components of 1 to 8 in the following [Table 1] are sequentially added to separate containers, and then subjected to medium-speed agitation to prepare a dispersion 1, and in order to 10 to 15 in 16 to 17 mixed solvents in another separate container. It is added while stirring slowly to prepare dispersion 2.

And after disperse | distributing the dispersion liquid 1 and the dispersion liquid 2 which were manufactured by the said method well, the thick-film one-component polyurethane coating composition was manufactured by the same method as Example 1.

                                                         (Unit: parts by weight) number
Ingredient Name
Example Comparative example One 2 3 One 2 3 One Polyester-based (number average molecular weight 1500 or less) ⑴ 21 21 30.5 21 21 30.5 2 Polyester type (number average molecular weight 5000 or less) 9 9 11 9 9 11 3 Titanium Dioxide (Pigment) 16 2 0.1 16 2 0.1 4 Inorganic Coloring Pigments (red) 0 14 0 0 14 0 5 Inorganic Color Pigment (Yellow) One 0 0 One 0 0 6 Inorganic Color Pigment (Black) 0 One 0 0 One 0 7 Butyl carbitol Acetate (solvent) 8.5 8.5 5 8.5 8.5 5 8 Block copolymer (dispersant) 0.8 0.8 0.1 0.8 0.8 0.1 9 Butyl cabitol (solvent) 10 10 6 10 10 6 10 Polyisocyanate ⑶ 18 18 27.7 20 20 31 11 Polypropylene wax 0.4 0.4 0.6 0.4 0.4 0.5 12 Acrylate Defoamer ⑷ 0.4 0.4 0.6 0.4 0.4 0.5 13 Acrylate Slip Agent 0.4 0.4 0.7 0.4 0.4 0.5 14 Polyurethane Polymer Solution ⑸ 2 2 3.3 0 0 0 15 Dibutyl tin dilaurate ⑹ 0.5 0.5 0.2 0.5 0.5 0.6 16 Silicon dioxide silica 2 2 2.2 2 2 2.2 17 Kocosol # 150 10 10 12 10 10 12

1) DA0515 (PPG ~ KOREA)

2) DA0615 (PPG ~ KOREA)

3) Block polyisocyanate of DESMODUR BL 4265 by BAYER

4) AP4615 (PPG ~ KOREA)

5) AR7850 (PPG ~ KOREA)

6) AIR PRODUCTS company dibutyl tin DI ~ LAURATE

2. Property test

The specimens were prepared using the thick film one-component polyurethane coating compositions of Examples and Comparative Examples prepared according to the method described above, and physical properties were evaluated according to the contents of Table 2 below, and the results are shown in Table 3 below. Indicated.

end. Psalm Writing

A thick film type undercoat (manufactured by our company) was coated on the chromate treated GI or GALVALUME under the conditions of a dry coating film of 30 to 50 µm, a drying temperature of 241 to 249 ° C, and a baking temperature of 40 to 60 seconds. The paints prepared according to the methods of 1 to 3 were each coated with a film thickness of 50 μm, a material surface temperature of 241 to 249 ° C., and a baking time of 40 to 60 seconds to perform a physical property test.

I. Test Methods

Test Items Assessment Methods  Gloss (Gloss 60˚)  Initial coating gloss measurement using a 60˚ gloss meter  Coating Hardness (MEK Rubs)  Measure the number of times the coating film is peeled off by rubbing the surface of the coating film with MEK solvent  Pencil hardness  Coating hardness is measured using UNI ~ Pencil (Mitsubishi)  Machinability (T ~ Bend)  Fold the specimen 180˚ to measure the degree of peeling of the coating  Adhesiveness (C.E.T)  5 mm measurement with Erichsen tester  Impact Resistance  Measured with Dupont tester under 1/2 ″ × 50cm × 500g  Acid resistance  96 hours spot test with 5% hydrochloric acid solution at room temperature  Alkali resistance  96 hours spot test with 5% sodium hydroxide solution at room temperature  Boiling water & adhesion  Adhesion (C.E.T) test after 2 hours immersion in boiling water (98 ± 2 ℃)  Navigator  Confirmation of coating appearance after 2 hours immersion in boiling water (98 ± 2 ℃)  Promoting Weather Resistance (W ~ O ~ M)  Measure color difference and gloss retention of coating after 3000 hours with W ~ O ~ M tester  Popping resistance  Visual observation judgment  Bubble resistance  Visual observation judgment

Test Items
Example Comparative example One 2 3 One 2 3 Gloss (Gloss 60˚) 10-65% 10-75% 10-75% 10-60% 10-60% 10-60% Coating Hardness (MEK Rubs) 100 times
More than 100 times
More than 100 times
More than 100 times
More than 100 times
More than 100 times
More than Pencil hardness F or more F or more F or more F or more F or more F or more Machinability (T ~ Bend) 5 points 5 points 5 points 5 points 5 points 5 points Adhesiveness (C.E.T) 5 mm
More than 5 mm
More than 5 mm
More than 5 mm
More than 5 mm
More than 5 mm
More than Impact Resistance Good Good Good Good Good Good Acid resistance Early and
same Early and
same Early and
same Early and
same Early and
same Early and
same Alkali resistance Early and
same Early and
same Early and
same Early and
same Early and
same Early and
same Boiling water & adhesion 100/100 100/100 100/100 100/100 100/100 100/100 Navigator Early and
same Early and
same Early and
same Early and
same Early and
same Early and
same Weathering resistance
(W ~ O ~ M)
Color
Retention Max 5 Max 5 Max 5 Max 5 Max 5 Max 5 Chalk
resistance Good Good Good Good Good Good  Popping resistance Good Good Good part
Occur part
Occur part
Occur  Bubble resistance Good Good Good part
Occur part
Occur part
Occur

According to the contents of [Table 3], Examples 1 to 3 and Comparative Examples 1 to 3 all use block polyisocyanate, and in the physical properties, the coating film hardness, pencil hardness, processability, adhesion, impact resistance, Although the physical properties of acid resistance, alkali resistance, non-water resistance and adhesion, non-water resistance, and accelerated weather resistance are all the same, Examples 1 to 3 are different from those of Comparative Examples 1 to 3 by using a polyurethane resin together with a block polyisocyanate. Compared with Comparative Examples 1 to 3 using the block polyisocyanate of, it was found that the coating film had excellent coating properties, gloss and popping and bubble resistance.

That is, the present invention was able to improve the coating film boiling problem generated in conventional thick film coating by using a block polyisocyanate with the introduction of a high boiling point ether solvent in a conventional low boiling hydrocarbon solvent.

As described above, those skilled in the art will understand that the thick film one-component polyurethane coating composition according to the preferred embodiment of the present invention can be variously changed and changed without departing from the technical spirit of the present invention. Could be.

Claims (5)

In the polyurethane coating composition, Per 100 parts by weight of the coating composition, Iii) polyester polyol resins and blocked polyisocyanate resins and polyurethanes  50 to 72.5 parts by weight as a mixed resin of the resin, Ii) 0.1 to 17 parts by weight of an inorganic color pigment, Iii) 23.0 to 30.5 parts by weight of a mixed solvent, Iii) 1.2 to 1.9 parts by weight of an antifoaming agent, Iii) 0.2 to 0.5 parts by weight of a curing accelerator, Viii) 0.1 to 0.8 parts by weight of a polymer type wet dispersion agent, The mixed resin is mixed with 30 to 41.5 parts by weight of polyester polyol resin, 18 to 27.7 parts by weight of block polyisocyanate resin and 2.0 to 3.3 parts by weight of polyurethane based on 100 parts by weight of the coating composition, The polyester polyol resin is mixed with 21 to 30.5 parts by weight of polyester polyol having a weight average molecular weight of 1,500 or less and 9 to 11 parts by weight of polyester polyol having a weight average molecular weight of 5,000 or less, based on 100 parts by weight of the coating composition, The block polyisocyanate is selected from one or more selected from the group consisting of fluorene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate or a trimer type isocyanate, and may be selected from methyl ethyl ketosim, dimethyl presol or A thick film one-component polyurethane coating composition, characterized in that it is synthesized using a blocking agent mixed with methyl ethyl ketosim and caprolactam. delete delete delete delete