KR100335311B1 - Paint composition containing gas-checking acrylic resin composition - Google Patents

Abstract

PURPOSE: Provided is a paint composition containing a gas-checking resistant acryl resin composition, which has excellent gas-checking resistance and high corrosion resistance and can improve workability and productivity. CONSTITUTION: The paint composition is produced by using 16-32pts.wt. of the gas-checking resistant acryl resin composition as a binder, wherein the acryl resin composition is produced by mixing 80-90pts.wt. of a base solution, an acryl monomer mixture containing 10-20pts.wt. of a reactive epsilon-caprolactone-based acryl oligomer derivative, and 0.6-1.0pts.wt. of a reaction initiator.

Description

Coating composition comprising a gas resistant acrylic resin composition

The present invention relates to a coating composition comprising a gas resistant acrylic resin composition, and more particularly, to a gas resistant acrylic resin composition comprising an acrylic resin composition having excellent corrosion resistance upon coating and having high corrosion resistance. It relates to a coating composition comprising a.

Industrial paints are mainly made of heat-drying type to increase the productivity of coating products. Paint is generally composed of a mixture of pigments, synthetic resins, solvents, crosslinking agents, additives, etc., double synthetic resins and crosslinking agents play an important role to greatly influence the physical properties of the coating film after coating. Synthetic resins for industrial paints are mainly used by attaching reactive functional groups to a skeleton such as polyester resins, acrylic resins or epoxy resins, and the synthetic resins are selected according to the physical properties of the coating film. Acrylic resin is mainly used for painting industrial steel appliances.

The main coating process of industrial paint is completed by first degreasing and chemical treatment of steel materials, and then going through the undercoat process to protect the material and improve adhesion to the top coat, and then finish the top coat with a beautiful appearance. At this time, the coating film is heat-dried by passing a heating furnace in the undercoat and top coat processes. City gas is mainly used as a heat source of the furnace, and incomplete combustion gas flows into the furnace according to the performance of the furnace, affecting the undried coating, which causes a coating failure. Collectively, this is called gas checking property.

In general, the incomplete combustion gas serves as a catalyst in contact with the undried wet coating film, thereby causing the coating film to be distorted by varying the curing rate at the upper and lower portions of the coating film. As a result, the appearance of poor gloss and wrinkles may occur. In order to prevent such gas checking phenomenon, it is common practice to add an inorganic acid or an organic acid, which catalyzes the hardening of the coating film, to the paint, and such a catalyst is a butanol solution obtained by diluting a strong acid such as hydrochloric acid, sulfuric acid, and nitric acid in butanol. Toluenesulfonic acid alone or a morpholine salt of toluenesulfonic acid. In addition, when the effect is insignificant, antioxidants 2,4-dimethyl-6-tert-butylbutylphenol, 2,6-ditert-butyl-4-methylphenol, and triethanolamine may be used in combination.

However, the method of adding an additive to the paint does not remove the fundamental gas checking phenomenon, and a significant difference occurs in the failure rate depending on the weather or the situation of the heating furnace during the operation.

Accordingly, an object of the present invention is to provide a gas resistant coating composition containing a gas resistant acrylic resin capable of providing a high corrosion resistance while fundamentally solving such a problem of gas checking.

In order to achieve the above object, the present invention is prepared by mixing an acrylic monomer mixture containing 80 to 90 parts by weight of the base solution, 10 to 20 parts by weight of reactive epsilon-caprolactone acrylic oligomer derivative and 0.6 to 1.0 parts by weight of the reaction initiator. A coating composition using a gas resistant acrylic resin as a binder is provided.

Hereinafter, the present invention will be described in detail.

The present invention does not solve the gas checking phenomenon by the method of adding the additive, but in order to solve the resin skeleton itself, reactive epsilon-caprolactone-based acrylic oligomer derivative (product produced by Daehan Paint Ink Co., Ltd. product name: ACR-1300) An acid catalyst effect is imparted by introducing into acrylic resin and introducing methacrylic acid. Reactive epsilon-caprolactone acrylic oligomers attached to the acrylic resin backbone, along with the other hydroxyl groups in the backbone of the acrylic resin, react with the film-forming crosslinking agent to prevent appearance defects or gloss by not causing a difference in reaction rate due to incomplete combustion gas. Defects, such as a fall, do not arise.

In addition, the present invention improves the corrosion resistance of the top coat in order to eliminate the undercoat process during the coating process for the purpose of resource, high productivity and cost reduction, that is, by introducing acrylic monomer containing glycidyl group into the acrylic backbone When the resin thus synthesized is used as a binder of the paint, it will have the same rust-preventing properties as the undercoating without the undercoating process.

The present invention synthesizes acrylic resin in the following manner to produce a paint, which provides a coating that can be coated with a coating without having a coating coating properties without a coating process.

Styrene, reactive epsilon-caprolactone acryl oligomer derivative, methacrylic acid, 2-hydroxyethyl methacryl, glycidyl methacryl, butylacryl, acrolein, methyl methacryl, butyl methacryl And other acrylic monomers are mixed, and radical reaction initiators such as benzoyl peroxide, azoisobutylonitrile, and hydrogen peroxide are dissolved and added dropwise into the base solution to obtain a glass transition temperature of 20-30 占 폚 and a molecular weight of 40,000-60,000. Acrylic resins can be synthesized. Here, it is known that methacrylic acid may be applied as a curing agent or a catalyst itself when the coating film is cured. However, the methacrylic acid may be used within 4% because it may cause a problem of paint storage stability. The reactive epsilon-caprolactone acryl oligomer derivative not only provides flexibility to the dry coating film but also plays a role of minimizing the effects of incombustible gases during the film forming crosslinking reaction. Glycidyl methacryl monomer plays a role in enhancing the corrosion resistance of the coating film by generating a hydroxyl group in the crosslinking reaction with the crosslinking agent, thereby improving adhesion to the material, but 12% In case of abnormal use, gas checking problem may be caused. The monomer containing other reactive functional groups affects the hardness and flexibility of the cured coating film and should be designed in consideration of the relationship.

The functional acrylic resin thus prepared is mixed with the general pigment to disperse, butoxy resin and block isocyanate are used as a crosslinking agent, and various organic solvents are added in an appropriate amount to make a homogeneous mixture. Add a small amount of additives such as pigment anti-settling agent, ultraviolet absorber, anti-fouling agent and then re-stirring to make a homogeneous mixture, the paint is completed.

Compared with the general acrylic heat-drying paint of the prepared paint, it can be seen that the anti-corrosion resistance is excellent, and the anti-corrosion property of the dry paint and the other coating without the paint coating is the same.

Hereinafter, the present invention will be described in detail through examples. However, the above embodiments do not limit the scope of the present invention.

Example 1

40 g of xylene and 50 g of normal butanol were put into a four-necked flask, heated to 115-120 ° C. while stirring, and then 100 g of the acrylic monomer mixture of Table 1 was homogeneously mixed and added dropwise over 2 hours while maintaining the temperature of the solution. Next, after reacting for 1 hour, 0.5 g of a benzoyl peroxide initiator is dissolved in 10 g of xylene, and the mixture is added dropwise over an hour. Thereafter, 0.3 g of a benzoyl peroxide initiator was added to a synthetic container in order to polymerize the unreacted monomer, followed by reaction for 2 hours, and then terminated. It synthesize | combined in this way and obtained the acrylic resin solution which has the characteristic value of glass transition temperature of 25 degreeC, and molecular weight of 53,000.

TABLE 1

Example 2

In the same manner as in Example 1, 100 g of the acyl monomer mixture of Table 1 was solution polymerized as a homogeneous mixture. It synthesize | combined in this way and obtained the acrylic resin solution which has the characteristic value of 25 degreeC Gardner viscosity Y, 48% of non volatile matters, 32 degreeC of glass transition temperature, and molecular weight 52,000.

Comparative Example 1

Synthetic resins used in general iron paints were synthesized from the compounds of Table 2 in the same manner as in Example 1. As a result of the synthesis, an acrylic resin solution having a Gardner viscosity of 25 DEG C, a 49% nonvolatile content, a glass transition temperature of 23 DEG C, and a molecular weight of 50,000 was obtained.

TABLE 2

In order to test the performance of each synthesized resin, the mixture was stirred evenly with the composition shown in Table 3, and then passed through a disperser two or more times to make a homogeneous mixture having a particle diameter of 10 μm or less.

TABLE 3

After dispersion, the composition of Table 4 was added to the dispersion of Table 3 and stirred to prepare a homogeneous mixed paint.

TABLE 4

Butoxymelamine and 1,6-cyclohexyl block diisocyanate used as a crosslinking agent in the preparation of the paint can be arbitrarily adjusted to 5-15 parts by weight depending on the hardness of the coating film, depending on the flexibility and workability of the coating film The present invention can be produced using 16-32 parts by weight of a gas resistant, highly corrosion-resistant acrylic resin.

The paint thus prepared is spray-coated to a zinc phosphate chemically treated cold rolled steel sheet to have a coating thickness of 30-40 μm, and left for 10 minutes, and then examined for physical properties of the coating film obtained by heating and drying in an oven at 150 ° C. for 20 minutes. . The oven used at this time was dried by injecting gas into the oven at a rate of 50 ml per minute in order to examine gas checkability.

The gas checking property can be judged visually by observing the dry coating film. If the gas checking property is not good, the coating gloss decreases and the surface becomes jagged. In general, the top coat is always applied after the bottom coat is applied on the protection side of the material. In this experiment, the top coat was applied without the bottom coat. In experiments on the protective side of the body, the coating was drawn with an X-shape, sprayed with a 35 ° C 5% sodium chloride solution for at least 240 hours, and the performance was judged by a corrosion resistance test that measured the distance the coating film was displaced from the area of X. It is common to do Table 5 shows the result.

TABLE 5

In Table 5, the corrosion resistance value is a value obtained by measuring the degree of peeling of the coating film from the X-shaped groove portion of the specimen, and the worse the corrosion resistance, the farther the distance from the separated part. This is a simple test of the phenomenon that the coating film falls off and rusts when the coating part of the steel structure is exposed to the rain for a long time.

Since the coating composition according to the present invention has excellent corrosion resistance and high corrosion resistance, it is possible to omit the undercoating process used for improving the rust resistance during the coating process of a conventional excellent anti-corrosive property, thus improving workability and productivity. This improves cost savings.

Claims (7)

80 to 90 parts by weight of the base solution, Acrylic monomer mixture comprising 10 to 20 parts by weight of reactive epsilon-caprolactone acrylic oligomer derivative and A coating composition using a gas resistant acrylic resin composition prepared by mixing 0.6 to 1.0 parts by weight of a reaction initiator as a binder. The coating composition according to claim 1, wherein the acrylic monomer mixture further comprises 4 to 12 parts by weight of an acrylic monomer having a glycidyl group. The coating composition according to claim 1 or 2, wherein the acrylic monomer mixture further comprises 2-4 parts by weight of methacrylic acid. The coating composition according to claim 1, wherein the acrylic resin composition has a glass transition temperature of 0 to 50 ° C and a molecular weight of 40,000 to 60,000. The coating composition according to claim 1, wherein solid content of the acrylic resin composition is 16 to 32 parts by weight. The coating composition according to claim 1, further comprising 5 to 15 parts by weight of a butoxymelamine resin having a molecular weight of 1,000 to 2,000. The coating composition according to claim 1, further comprising 5 to 15 parts by weight of 1,6-cyclohexyl block diisocyanate.