KR20200086898A - Water soluble epoxy coating composition - Google Patents

Abstract

The present invention relates to a water-soluble epoxy paint composition comprising a water-dispersible epoxy-based amine resin and a water-dispersible epoxy resin.

Description

Water-soluble epoxy coating composition {WATER SOLUBLE EPOXY COATING COMPOSITION}

The present invention relates to a water-soluble epoxy coating composition.

When preparing an epoxy coating composition, a method of emulsifying or dispersing an epoxy resin or an amine resin by forcibly dispersing it in a water-soluble solvent is generally used. In addition, solvents are also included in additives such as dispersants, antifoaming agents, and leveling agents that are added to improve the properties of paints and coatings. These solvents contain volatile organic compounds (VOC), which can cause environmental pollution by generating a lot of VOC when painted in a place where environmental facilities are not properly equipped.

VOCs cause photochemical reactions in the atmosphere after they are released, producing photochemical oxidizing substances such as ozone or causing photochemical smog. In addition, there is also a problem that odor is generated by remaining in the product. In particular, when the coating material is applied to a semiconductor wafer, display, or the like, spots may be generated on the surface of the product to increase the defect rate.

As a method for solving the above problem, a technique using a water-soluble coating using water as a solvent instead of an organic solvent, a coating using a specific type of additive, a powder coating using no solvent, or the like has been developed.

As an example, Korean Patent Registration No. 10-1459263 discloses an epoxy resin coating composition comprising an epoxy resin, an amine resin and liquid tourmaline. However, the paint still has a high level of VOC content due to the use of an organic solvent, and there is a problem that properties such as gloss are also poor.

Accordingly, while reducing the VOC content to solve the environmental pollution problem, there is still a need for an epoxy coating composition having excellent physical properties, such as appearance properties and mechanical properties, which are also generally required.

The present invention provides a water-soluble epoxy coating composition having a very low VOC content and odor strength.

The present invention includes a curing agent comprising a water-dispersing epoxy-based amine resin and a water-dispersing epoxy resin, the subject and curing agent having a VOC content of 0 to 15 g/L, and an odor strength (OMX-SR). A water-soluble epoxy coating composition of 0 to 30 is provided.

The present invention provides an environmentally friendly water-soluble epoxy coating composition having a very low VOC content and odor strength. When the coating according to the present invention is applied, it is possible to lower the defect rate of products due to VOC when manufacturing semiconductor wafers and displays. In addition, the paint of the present invention does not generate odor after the coating process and the coating is completed, and is not only beneficial to the health of the painter, but can also be applied to floors of sites that are sensitive to odor, such as apartments and hospitals.

Hereinafter, the present invention will be described in detail. However, the present invention is not limited only to the following contents, and each component may be variously modified or selectively mixed as necessary. Therefore, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The water-soluble epoxy coating composition according to the present invention includes a subject comprising a water-dispersion-type epoxy-based amine resin and a curing agent comprising a water-dispersion-type epoxy resin. Looking at the composition of the water-soluble epoxy coating composition of the present invention as follows.

Water-dispersion type epoxy-based amine resin

The water-soluble epoxy coating composition according to the present invention includes a water-dispersive epoxy-based amine resin as a subject. The epoxy-based amine resin reacts with a curing agent to form a coating film, impart gloss, and serves to provide basic properties of the coating film such as high corrosion resistance, processability, chemical resistance, hardness, and adhesion.

The epoxy-based amine resin may be prepared from an amine compound and an epoxy resin.

The amine compound is not particularly limited, and for example, one or more amine compounds among propylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentaamine, metaxylenediamine, and isophoronediamine may be used.

The epoxy resin is not particularly limited as long as it is a conventional epoxy resin known in the art. Non-limiting examples of usable epoxy resins include bisphenol A type epoxy resins, cresol novolac type epoxy resins, bisphenol F type epoxy resins, phenol novolac type epoxy resins, bisphenol A novolac type epoxy resins, and aromatic hydrocarbon formaldehyde resin modifications And phenol resin type epoxy resins, triphenylmethane type epoxy resins, tetraphenylethane type epoxy resins, dicyclopentadiene phenol addition reaction type epoxy resins, or mixtures thereof.

The amine value of the epoxy-based amine resin may be 120 to 200 mgKOH/g, for example, 140 to 175 mgKOH/g. When the amine value is less than 120 mgKOH/g, problems such as adhesion and glossiness of the coating film may occur, and when it exceeds 200 mgKOH/g, workability and strength of the coating film may decrease.

The active hydrogen equivalent of the epoxy-based amine resin is not particularly limited, but may be 100 to 300 g/eq, for example, 120 to 240 g/eq. The viscosity (25° C.) of the epoxy-based amine resin is not particularly stable, but may be 1,000 to 10,000 cps, for example, 2,000 to 5,000 cps, and solid content may be 40 to 70%, for example, 45 to 60%. have.

In addition, the epoxy-based amine resin may have a VOC content of 0 to 15 g/L, for example, 0 to 5 g/L, and an odor intensity (OMX-SR) of 0 to 30, for example, 0 to 15.

The content of the epoxy-based amine resin is not particularly limited, and may be included in 1 to 50% by weight, for example, 5 to 35% by weight based on the total weight of the water-soluble epoxy coating composition. When the content of the epoxy-based amine resin falls within the above-mentioned range, the basic physical properties of the coating film are good and the odor strength is excellent.

Water dispersion type epoxy resin

The water-soluble epoxy coating composition according to the present invention includes a water-dispersing epoxy resin as a curing agent.

The epoxy resin is not particularly limited as long as it is a conventional epoxy resin known in the art. Non-limiting examples of the epoxy resins that can be used include, bisphenol A-type epoxy resin, cresol novolac-type epoxy resin, bisphenol F-type epoxy resin, phenol novolac-type epoxy resin, bisphenol A novolac-type epoxy resin, aromatic hydrocarbon formaldehyde resin Modified phenolic resin type epoxy resins, triphenylmethane type epoxy resins, tetraphenylethane type epoxy resins, dicyclopentadiene phenol addition reaction type epoxy resins, or mixtures thereof.

The epoxy equivalent of the epoxy resin is not particularly limited, but may be 100 to 300 g/eq, for example, 190 to 210 g/eq. When the epoxy equivalent is within the aforementioned range, the degree of curing of the coating film may be improved.

The viscosity (25°C) of the epoxy resin is not particularly limited, but may be 1,000 to 10,000 cps, for example, 4,000 to 6,000 cps, and solid content may be 60 to 80%, for example, 65 to 75%.

In addition, the epoxy resin may have a VOC content of 0 to 15 g/L, for example, 0 to 5 g/L, and an odor intensity (OMX-SR) of 0 to 30, for example, 0 to 15.

The epoxy resin may be included in 1 to 65% by weight, for example, 5 to 50% by weight based on the total weight of the water-soluble epoxy coating composition. When the content of the epoxy resin is less than 1% by weight, curability and moldability may occur, and when it exceeds 65% by weight, reliability may decrease due to an increase in moisture absorption, and strength may be relatively lower.

solvent

The water-soluble epoxy coating composition of the present invention may further include a solvent. The solvent serves to control the viscosity, dispersibility, and the like of the composition.

As the solvent, water, for example, ionic water, pure water, ultrapure water, distilled water, or the like can be used.

The content of the solvent may be an amount such that the total weight of the water-soluble epoxy coating composition is 100% by weight, for example, 0.5 to 20% by weight relative to the total weight of the composition. When the content of the solvent falls within the above-described range, the VOC content and odor intensity are low, thereby increasing work efficiency and preventing environmental pollution.

Dispersant

The water-soluble epoxy coating composition of the present invention may further include a dispersant commonly used in the field of epoxy coating, within a range that does not impair the inherent properties of the composition. The dispersant serves to improve the flowability and dispersibility of the composition.

Specific examples of such dispersants include anionic dispersants, cationic dispersants, amphoteric dispersants, nonionic dispersants, or mixtures thereof. Non-limiting examples of the dispersant include, polyphosphate, polycarboxylate, polyacrylate, sodium polyacrylate, polyoxyethylene alkyl phenol ether, polyoxyethylene styrenated phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene Polyoxypropylene block polymers, polyoxyethylene styrenated phenyl ether sulfate ester salts, alkyldiphenyl ether disulfonate salts, polyacrylic acid soda salts, and ammonium salts of half esters of styrene maleic acid copolymers.

As the dispersant, an acid value of 50 to 100 mgKOH/g, for example, 65 to 85 mgKOH/g may be used. Further, as the dispersant, a pH of 6 to 10, for example, 7 to 9, and a viscosity (25°C) of 500 to 5,000 mPas, for example, 1,000 to 4,000 mPas may be used.

The content of the dispersant may be included in an amount of 0.1 to 10% by weight, for example, 0.5 to 6% by weight based on the total weight of the composition. When the content of the dispersant is less than 0.1% by weight, flowability and dispersibility may be reduced, and when it exceeds 10% by weight, water resistance and anti-foaming properties of the coating film may be reduced.

additive

The water-soluble epoxy coating composition of the present invention may further include additives commonly used in the field of epoxy coatings, within a range that does not impair the inherent properties of the composition.

Non-limiting examples of additives usable in the present invention include antifoaming agents, extender pigments, leveling agents, colorants, surface modifiers, adhesion improvers, flame retardants, light absorbers, desiccants, hygroscopic agents, and the like. The water-soluble epoxy coating composition of the present invention may contain an additive that does not contain an organic solvent.

The antifoaming agent serves to suppress the formation of bubbles when forming the coating film. As the antifoaming agent, components known in the art may be used without limitation, and for example, one or more of silicone antifoaming agents and non-silicone antifoaming agents may be used.

The antifoaming agent may be included in an amount of 0.1 to 10% by weight based on the total weight of the coating composition, and when the content of the antifoaming agent falls within the above-described range, it is possible to effectively remove air bubbles and secure excellent coating film properties.

The extender pigment fills the pores in the coating film, complements the formation of the coating film, and plays a role in imparting repellency or mechanical properties to the coating film. As the extender pigment, components commonly used in the field of epoxy coatings can be used without limitation.

Non-limiting examples of the extender pigment include calcium carbonate, feldspar, barium sulfate, silica, alumina hydroxide, magnesium hydroxide, titanium dioxide, magnesium carbonate, alumina, mica, olestonite, talc, aluminum nitride, aluminum oxide, and the like. , These may be used alone or in combination of two or more.

The average particle diameter of the extender pigment is not particularly limited, and may be, for example, 0.1 to 10 μm, for example, 0.5 to 2 μm. In addition, the shape of the extender pigment may be spherical or amorphous, and is not particularly limited thereto.

The content of the extender pigment may be 1 to 30% by weight based on the total weight of the coating composition. When the content of the extender pigment is less than 1% by weight, the hiding rate of the material may be lowered, and when it exceeds 30% by weight, adhesion of the coating film may be lowered.

The leveling agent serves to improve the smoothness of the coating film. As the leveling agent, components commonly used in the field of epoxy coatings can be used without limitation, for example, acrylic, silicone, polyester, and amine leveling agents, and the like. The leveling agent content may be 0.1 to 5% by weight based on the total weight of the coating composition.

The colorant is used to impart a predetermined color to the paint. As the colorant, components commonly used in the field of epoxy coatings can be used without limitation. As an example, an aqueous colorant may be used, in which case VOC generation can be prevented, compatibility with a water-soluble paint is good, and color separation and color discoloration hardly appear. The content of the colorant may be 1 to 40% by weight based on the total weight of the coating composition.

The coating composition of the present invention can be prepared according to conventional methods known in the art. For example, a water-dispersive epoxy-based amine resin, a water-dispersive epoxy resin, and a solvent (water), a dispersant, an antifoaming agent, an extender pigment, a leveling agent, and an aqueous colorant, respectively, may be prepared by mixing them, if necessary.

The coating composition according to the present invention can be prepared by mixing a subject and a curing agent. Subjects of the present invention may have a VOC content of 0 to 15 g/L, for example 0 to 5 g/L, and an odor intensity (OMX-SR) of 0 to 30, for example 0 to 15. In addition, the curing agent of the present invention may have a VOC content of 0 to 15 g/L, for example, 0 to 5 g/L, and an odor intensity (OMX-SR) of 0 to 30, for example, 0 to 15.

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are only to aid the understanding of the present invention, and the scope of the present invention is not limited to the examples in any sense.

[Example 1-4 and Comparative Example 1-3]

According to the composition shown in Table 1, a water-dispersible epoxy-based amine resin, a water-dispersible epoxy resin, a dispersant, additives, and water were mixed to prepare water-soluble epoxy coating compositions of Examples 1-4 and Comparative Examples 1-3. In Table 1 below, the unit of use of each component is parts by weight.

The VOC content of each prepared subject and curing agent was measured using Gas Chromatography (GC), and the odor intensity was measured using the OMX-SR odor measuring device immediately after opening the sealed composition.

Epoxy-based amine resin 1: modified polyamine (Modified Polyamine, SH 875W, Sejin E&C, amine value 157.5 mgKOH/g, active hydrogen equivalent 120 g/eq, viscosity (25 ℃) 2,500 cps, solid content 50%)

Epoxy-based amine resin 2: modified aliphatic amine (Modified Aliphatic amine, ANQUAMINE 401, Evonik, amine value 255 mgKOH/g, active hydrogen equivalent 200 g/eq, viscosity (25 ℃) 10,000 cps, solid content 70%)

Epoxy-based amine resin 3: Mannich base adduct (ANQUAMINE 287, Evonik, amine value 165 mgKOH/g, active hydrogen equivalent 240 g/eq, viscosity (25 °C) 900 cps, solid content 50%)

Epoxy-based amine resin 4: Polyaminoamide Aqueous solution (ARADUR 340, Huntsman, amine value 390 mgKOH/g, active hydrogen equivalent 113 g/eq, viscosity (25 ℃) 20,000 cps, solid content 50%)

Dispersant 1: BYK 194N, BYK

Dispersant 2: TEGO660C, EVONIK

Antifoaming agent 1: Silicone (FOAMEX 810, EVONIK)

Antifoaming agent 2: Non-silicone type (BYK 012, BYK)

Constitution pigment: Barium Sulfate

Leveling agent: Polyether Modified Siloxane

Aqueous colorant: Pigment Green 7 (BASF)

Epoxy resin 1: BPA liquid emulsion (BPA liquid Emulsion, SR 827W, Sejin E&C, epoxy equivalent 200 g/eq, viscosity (25 ℃) 5,500 cps, solid content 70%)

Epoxy resin 2: BPA solid emulsion (BPA Solid Emulsion, EM-101-50, Kukdo Chemical, epoxy equivalent 500 g/eq, viscosity (25 ℃) 5,500 cps, solid content 47%)

Epoxy resin 3: BPA liquid emulsion (BPA liquid Emulsion, KEM-128, Kukdo Chemical Co., Ltd., epoxy equivalent 200 g/eq, viscosity (25 ℃) 5,500 cps, solid content 70%)

[Physical property evaluation]

The physical properties of the coating compositions prepared in Examples 1-4 and Comparative Examples 1-3 were measured as follows, and the results are shown in Table 2 below. Here, the coating composition is a mixture of a main agent and a curing agent in a weight ratio of 1.7:1.

Coverage rate

It was measured according to ASTM D5150.

Polish

Gloss was measured at a measurement angle of 60° according to ASTM D523.

(Excellent: measured value> 85, good: 80 <measured value ≤ 85, normal: 75 <measured value ≤ 80, defective: measured value ≤ 75)

VOC content

VOC content was measured using Gas Chromatography (GC).

Odor intensity

As soon as the sealed raw material was opened, the odor intensity was measured using a odor measuring equipment OMX-SR (Shinyei) with a distance of about 2 cm between the raw material and the measuring sensor.

As shown in Table 2, the coating composition of Examples 1-4 according to the present invention has better overall properties than Comparative Examples 1-3. In particular, it was confirmed that the coating composition of Example 1-4 using the subject and the curing agent according to the present invention has a very low VOC content and exhibits excellent odor strength.

Claims (5)

The subject comprises a water-dispersed epoxy-based amine resin and a curing agent comprising a water-dispersed epoxy resin,
The subject and the curing agent is a water-soluble epoxy coating composition having a volatile organic compound (VOC) content of 0 to 15 g/L and an odor strength (OMX-SR) of 0 to 30. The epoxy-based amine resin has an amine value of 120 to 200 mgKOH/g, an active hydrogen equivalent of 100 to 300 g/eq, a viscosity (25°C) of 1,000 to 10,000 cps, and a solid content of 40 to Water-soluble epoxy coating composition of 70%. The water-soluble epoxy coating composition of claim 1, wherein the epoxy resin has an epoxy equivalent of 100 to 300 g/eq, a viscosity (25°C) of 1,000 to 10,000 cps, and a solid content of 60 to 80%. The water-soluble epoxy coating composition of claim 1, wherein the epoxy coating has an acid value of 50 to 100 mgKOH/g, a pH of 6 to 10, and a viscosity (25°C) of 500 to 5,000 mPas. The water-soluble epoxy coating composition according to claim 1, comprising 1 to 50% by weight of the epoxy-based amine resin and 1 to 65% by weight of the epoxy resin, based on the total weight of the water-soluble epoxy coating composition.