KR20190068054A - Water-based paint composition having excellent water resistance and water-based paint prepared therefrom - Google Patents

Abstract

The present invention relates to a water-based paint composition comprising a water-soluble emulsion, cellulose ether, a pigment, and water; and a water-based floor paint produced from the same. In particular, the cellulose ether comprises at least one selected from the group consisting of: highly substituted hydroxyethyl methyl cellulose with 20-30 wt% of methyl group substitutions and 5-10 wt% of hydroxyethyl group substitutions; and highly substituted hydroxypropyl methyl cellulose with 15-25 wt% of methyl group substitutions and 25-35 wt% of hydroxypropyl group substitutions. As described above, there may be provided a water-based paint composition which comprises cellulose ether having particular substitutions, and thus has satisfactory viscosity, storage stability, and workability while having excellent water resistance. Consequently, the water-based paint composition according to the present invention may be used for finishing materials in construction industries, and particularly may be preferably used for floors that require high water resistance.

Description

[0001] The present invention relates to an aqueous paint composition having excellent water resistance and a water-based paint for flooring prepared therefrom,

The present invention relates to a water-based paint composition and a water-based paint for flooring prepared therefrom, and more particularly to a water-based paint for flooring made of at least one selected from the group consisting of highly substituted hydroxypropylmethylcellulose and highly substituted hydroxyethylmethylcellulose having a specific substitution ratio An aqueous paint composition having excellent water resistance by containing cellulose ether as a thickener for water-based paints, and a water-based paint for flooring prepared therefrom.

Generally, a paint is a general term of a colored paint which is formed by mixing a pigment (pigments) with a vehicle or a binder and is used for forming a thin coating film on the object to provide protection, decoration, and identification Is used.

These paints are classified into water-based and oil-based paints. Water-based paints that use water as a solvent have the characteristics of rapid drying and odorlessness, and thus are widely used for finishing materials for cement, gypsum board, mortar, wallpaper and flooring Lt; / RTI >

Specific examples of the components of the aqueous paint include resins, pigments, and water. Resins used in water-based paints for architectural finishes are emulsion resins, such as acrylic emulsion resins, and water-based paints using such emulsion resins are also called latex paints.

However, it is difficult to satisfactorily satisfy the various physical properties required for water-based paint by the above-mentioned components alone. Thus, if necessary, additives may be used to improve the physical properties of water-based paints. These additives only play a very important role in aqueous paint, although only a small amount is formulated. For example, cellulose derivatives impart physical properties such as viscosity, water retention and rheology improvement in latex-based paints and are used for workability, storage stability, and the like.

As a conventional technique for such water-based paints, Patent Document 1 (Chinese Patent Publication No. 103666143) discloses a water-based paint using hydroxyethyl cellulose ether as a cellulose ether and an acrylic latex binder as an emulsion . The water-based paint disclosed in Patent Document 1 is a road marking paint that reflects light and has a drawback that it is excellent in viscosity, anti-cracking, and storage stability, but is poor in water resistance.

As another conventional technique, Patent Document 2 (Korean Patent Laid-Open No. 10-2017-0084747) includes an acrylic emulsion, a cellulose thickener, an alkali swellable emulsion thickener, a pigment, a synthetic urethane thickener and the remainder water, Discloses an aqueous paint composition using a mixture of two cellulose thickeners having a hydroxyalkyl cellulose as a main chain, and Patent Document 3 (Chinese Patent Laid-open No. 104271681) describes water, a color pigment, a hydroxyalkylcellulose and a water-soluble styrene Desc / Clms Page number 2 > acrylic resin in a certain amount.

However, the hydroxyalkylcellulose used in the prior art, such as hydroxyethylcellulose, can impart excellent tinting or storage stability, but it is more hydrophilic than cellulose ethers having other substituents, . When the above water-repellent water-based paint is used as a finishing material for architectural applications, in particular, as a flooring paint, not only the appearance but also the durability of the flooring can be deteriorated due to moisture permeation.

However, in order to solve this problem, when cellulose ether having other substituents having high hydrophobicity is used as a thickener for water-based paint, without using hydroxyethylcellulose, which has been mainly used as a thickener in conventional water-based paints, Water-based paints having good viscosity and improved water resistance can be provided. However, water-based paints have been limited in their use due to their poor storage stability and toughness.

Accordingly, there is a need for studies on a water-based paint composition to which cellulose ether having a reduced hydrophilicity is applied so as to impart an excellent water resistance while imparting a certain level of viscosity, storage stability, and workability.

CN 103666143 A KR 1020170084747 A CN 104271681 A

The present invention includes one or more cellulose ethers selected from the group consisting of highly substituted hydroxypropylmethylcellulose and highly substituted hydroxyethylmethylcellulose having a specific substitution ratio, thereby having good viscosity, storage stability and workability and excellent water resistance To provide an aqueous paint composition.

The present invention also provides an aqueous paint for flooring prepared from the aqueous paint composition.

In order to solve the above problems, the present invention provides a water-soluble emulsion, a cellulose ether, a pigment and water, wherein the cellulose ether has a methyl group substitution ratio of 20 to 30% by weight and a hydroxyethyl group substitution ratio of 5 to 10% Substituted hydroxyethyl methylcellulose; Substituted hydroxypropyl methylcellulose having a methyl group substitution ratio of 15 to 25% by weight and a hydroxypropyl substitution ratio of 25 to 35% by weight.

The cellulose ether may not contain hydroxyethyl cellulose.

And, the content of the cellulose ether may be 0.1 to 1.0 wt% based on the total weight of the aqueous paint composition.

The water-soluble emulsion may include one or more selected from the group consisting of an acrylic emulsion, a vinyl acetate emulsion, a vinyl acetate emulsion, a styrene acrylic emulsion, a water-soluble silicone emulsion, and a water-soluble alkyd emulsion.

The aqueous paint composition according to the present invention may further comprise at least one additive selected from the group consisting of a wetting agent, a dispersing agent, an antifoaming agent, a cryoprotectant, an antiseptic agent, a pH adjusting agent and a film forming auxiliary agent.

On the other hand, the present invention provides an aqueous paint for flooring prepared from the aqueous paint composition.

The aqueous paint composition according to the present invention contains one or more kinds of cellulose ethers selected from the group consisting of highly substituted hydroxypropyl methylcellulose and highly substituted hydroxyethyl methylcellulose having a specific substitution ratio as described above, , An aqueous paint composition having improved workability and improved water resistance can be provided.

Therefore, the aqueous paint composition according to the present invention can be suitably used as a flooring paint requiring finishing use in the field of construction, particularly excellent water resistance.

The present invention relates to an aqueous paint composition comprising a water-soluble emulsion, a cellulose ether, a pigment and water, and a paint for flooring prepared therefrom, wherein the cellulose ether has a methyl group substitution ratio of 20 to 30% by weight and a hydroxyethyl group substitution ratio of 5 - 10% by weight of high substituted hydroxyethyl methylcellulose; And high substituted hydroxypropylmethyl cellulose having a methyl group substitution ratio of 15 to 25% by weight and a hydroxypropyl substitution ratio of 25 to 35% by weight.

Generally, the water resistance of an aqueous paint composition is determined by the raw materials of paints, especially hydrophilic substances such as water-soluble emulsions and the like, but also by the degree of substitution of cellulose ether which is a thickener. That is, in the case of the cellulose ether having a higher substitution rate of hydrophobic groups than the hydrophilic group substitution ratio, the affinity with water is low, and thus an aqueous paint composition having relatively high water resistance can be provided. However, water-based paint compositions require not only water resistance but also physical properties such as viscosity, storage stability or workability, so that the proper replacement ratio of the hydrophilic group and the hydrophobic group is most important.

Specifically, in the case of hydroxyethylcellulose containing only a representative hydroxyethyl group, which is a hydrophilic group, as a substitute, it has been mainly used as a conventional thickener for water-based paint because of its excellent storage stability and coloring power. However, It was not enough to be used as a thickener for waterborne paint for flooring. Therefore, when the cellulose ether containing no or only a small amount of hydroxyethyl groups and containing a methyl group as a representative hydrophobic group at an excessively high substitution ratio is used as a thickener for water-based paints, the water resistance can be improved. However, Basic properties such as thickening property, storage stability or workability may be deteriorated. As a result of intensive research to solve such a problem, the present inventors have found that high substituted hydroxyethyl methylcellulose having a methyl group substitution ratio of 20 to 30% by weight and a hydroxyethyl group substitution ratio of 5 to 10% by weight; Substituted hydroxypropyl methylcellulose having a methyl group substitution ratio of 15 to 25% by weight and a hydroxypropyl substitution ratio of 25 to 35% by weight is used as a thickener for water-based paints, , Storage stability, workability, and the like, and has improved water resistance, and completed the present invention.

As described above, hydroxyethylmethylcellulose, which is a type of cellulose ether contained in the aqueous paint composition according to the present invention, has a methyl group substitution ratio of 20 to 30% by weight and a hydroxyethyl group substitution ratio of 5 to 10% by weight. When the methyl group substitution ratio is less than 20 wt% or the hydroxy ethyl group substitution ratio is more than 10 wt% in the hydroxyethyl methylcellulose, the effect of improving the water resistance of the aqueous paint composition is insignificant. On the other hand, when the methyl group substitution ratio is more than 30% by weight or the hydroxyethyl group substitution ratio is less than 5% by weight, physical properties such as viscosity, storage stability or workability are deteriorated. In the hydroxyethylmethylcellulose, the methyl group substitution ratio may be preferably 25 to 28% by weight, and the hydroxyethyl group substitution ratio may be preferably 8 to 10% by weight. In this case, So that it is preferable.

In addition, the hydroxypropylmethylcellulose has a methyl substitution ratio of 15 to 25% by weight and a hydroxypropyl substitution ratio of 25 to 35% by weight. When the methyl group substitution ratio is less than 15% by weight or the hydroxypropyl group substitution ratio exceeds 35% by weight in the hydroxypropyl methyl cellulose, the effect of improving the water resistance of the aqueous paint composition is insignificant. On the other hand, when the methyl group substitution ratio is 25% By weight or a hydroxypropyl substitution ratio of less than 25% by weight results in poor physical properties such as viscosity, storage stability or workability. In the hydroxypropylmethyl cellulose, the methyl group substitution ratio may be preferably in the range of 15 to 20% by weight, and the hydroxypropyl substitution ratio may be in the range of 30 to 35% by weight. In this case, the water- Can be provided.

Here, the term "substitution ratio" means the ratio of the total atomic weight of the elements constituting each substituent (R) among the total atomic weights of the elements constituting the repeating unit of the substituted cellulose as shown in the following formula (1).

Formula 1

Wherein, R is, independently of each other _{-H, CH 3, -CH 2 CH} 2 OH or -CH ₂ CHOHCH _3, n is an integer of 1 or more.

In the present invention, the cellulose ether may not contain hydroxyethyl cellulose. As described above, when only one or more selected from the group consisting of highly substituted hydroxyethyl methyl cellulose and highly substituted hydroxypropyl methyl cellulose having a specific substitution ratio according to the present invention is contained as the thickening agent, the water- Can be provided. Such water-based paints can be more preferably used for applications such as floor marking applications where water resistance is particularly important, such as road marking on the roads.

The viscosity of the cellulose ether is preferably 10,000 to 70,000 cps when measured at 20 캜 and 20 rpm using a Brookfield viscometer based on an aqueous solution having a concentration of 2.0% by weight. When the viscosity of the cellulose ether is within the above range, it is excellent in viscosity efficiency, and it can be provided with the thickening property required for water-based paint even at a small use amount, which is very economical.

The content of the cellulose ether may be 0.1 to 1.0 wt% based on the total weight of the aqueous paint composition. When the content of the cellulose ether is within the above range, the water-based paint composition can be improved in water resistance while imparting sufficient viscosity, storage stability, and workability to the water-based paint composition.

The water-soluble emulsion as a constituent of the aqueous paint composition according to the present invention together with the cellulose ether is a binder resin, which is attached to a conductor such as a general concrete or mortar to form a coating film which is cured by volatilization of water at normal temperature.

The water-soluble emulsion may include one or more selected from the group consisting of an acrylic emulsion, a vinyl acetate emulsion, a vinyl acetate emulsion, a styrene acrylic emulsion, a water-soluble silicone emulsion, and a water-soluble alkyd emulsion. For example, an acrylic emulsion or a vinyl acetate emulsion can be prepared by emulsion polymerization of an acrylic monomer composition or a vinyl acetate monomer composition in an aqueous medium (e.g., water) in the presence of a polyvinyl alcohol-based material.

The polyvinyl alcohol-based material may include an anion-modified polyvinyl alcohol such as a sulfonic acid-modified polyvinyl alcohol, a carboxylic acid-modified polyvinyl alcohol, or a combination thereof.

The acrylic monomer composition may include an acrylic monomer, and the vinyl acetate monomer composition may include a vinyl acetate monomer. The acrylic monomer composition and the vinyl acetate monomer composition may further contain other components.

The vinyl acetate-based monomer may include vinyl acetate. Examples of the acrylic monomer include ethyl acrylate, ethyl methacrylate, methyl acrylate, methyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate , Butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, cyclohexyl acrylate, alkoxyethyl acrylate, or combinations thereof.

The other component may be a monomer copolymerizable with the vinyl acetate-based monomer and the acrylic monomer (e.g., divinylbenzene, divinyl adipate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) Acrylate); Water-soluble oligomers (e.g., 2-methacrylamide-2-methylpropanesulfonic acid copolymer, sodium methacrylate-4-styrene sulfonate copolymer, polyvinylpyrrolidone, poly (meth) acrylate); Polymerization initiators (for example, potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide); Polymerization regulators (e. G., Methanol, ethanol, propanol, acetone, dodecyl mercaptan); Emulsifiers (e. G., Sodium lauryl sulfate), and combinations thereof.

The water-soluble emulsion may be contained within the range of contents commonly used in this field, and is preferably contained in the range of 10 to 40% by weight, based on the total weight of the aqueous paint composition. When the water-soluble emulsion is contained within the above-mentioned range, it is possible to provide a water-based paint excellent in coating film forming ability and excellent in durability such as water resistance and alkali resistance, and further, a high quality water- Can be provided.

The pigment included in the aqueous paint composition according to the present invention may be a coloring pigment such as titanium dioxide and also a body pigment such as aluminum silicate, calcium carbonate, talc, or combinations thereof. Can be used.

Here, the pigment may be contained within the range of contents commonly used in this field, and preferably it may be contained in the range of 20 to 60% by weight based on the total weight of the aqueous paint composition. When the pigment is contained within the above range, the phenomenon of separation of the solid phase pigment in the paint can be reduced, and problems such as dropping of the pigment at the contact interface at the time of forming the coating film are reduced, and a coating film excellent in durability can be obtained.

The water used in the aqueous paint composition according to the present invention may be included within the range of contents commonly used in this field, and preferably it may be contained in the range of 10 to 40% by weight, based on the total weight of the aqueous paint composition. When the water is contained within the above range, it is preferable that the powdery material used as the paint raw material can be sufficiently dispersed and the thickening effect can be increased.

In addition, the aqueous paint composition according to the present invention may further comprise at least one additive or organic solvent or a hydrophilic solvent (polar solvent) in the group consisting of a wetting agent, a dispersing agent, an antifoaming agent, a cryoprotectant, an antiseptic agent, a pH adjusting agent and a film- have. The total amount of the additives and the solvent is not particularly limited, but may be 0.1 to 10% by weight based on the total weight of the aqueous paint composition.

Specifically, the wetting agent may be any of those commonly used in the art, including, for example, Carbowet 106 of Air product, BYK-3400 of ALTANA, TRITON ^TM CF-10 of DOW, or combinations thereof have.

As the dispersing agent, any of those generally used in the art may be used without limitation, and may include, for example, sodium citrate, calcium stearate, zinc stearate, distearyldimethylammonium chloride, or a combination thereof.

Examples of the antifoaming agent include those commonly used in this field, such as dimethylpolysiloxane, silicone, silica, sorbitan monostearate, silicone resin, decanoic acid, lauric acid, myristic acid, Acid, stearic acid, oleic acid, mineral oil, oxysterine, or combinations thereof.

Examples of the freezing inhibitor include those commonly used in the art, including, for example, ethylene glycol, propylene glycol, sodium chloride, calcium chloride, or combinations thereof.

Examples of the preservative include, but are not limited to, those commonly used in the art, including, but not limited to, methanethiol, ethanethiol, 1-propanethiol, 2-propanethiol, butanethiol, tert-butyl mercaptan, pentanethiol, coenzyme A, glutathione, cysteine, 2-mercaptoethanol, dithioerythritol, 2-mercaptoindole, transglutaminase, or a combination thereof.

The pH regulator may be any one generally used in the art without limitation, and examples thereof include ammonia anhydride, ammonium phosphate, dimethylethanolamine, formic acid, sodium bicarbonate, sodium bicarbonate, triethylamine, .

As the above-mentioned film-forming auxiliary agent, those commonly used in this field can be used without limitation, such as Texanol ^TM (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate) of Eastman chemical company, Dow Of butyl carbitol, dipropylene glycol butoxy ether of Lyondell Chemical Company, or combinations thereof.

Examples of the solvent include organic solvents such as methanol, ethanol, acetone, Tertiary butyl alcohol (TBA), isopropyl alcohol, isopropyl alcohol, Isopropyl alcohol (IPA), or a combination thereof.

The water-based paint composition according to the present invention having the above-described constitution can provide a water-based paint having good viscosity, storage stability, workability, and excellent water resistance. Accordingly, the water-based paint composition provided according to the present invention can be widely used as a finishing material in the construction field such as cement, gypsum board, mortar surface, wallpaper, flooring material and the like. Especially, a water-based paint for flooring, Can be preferably used as a road-marking paint for lane marking.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example 1

An aqueous paint composition was prepared with the compositions shown in Table 1 below. At this time, high substituted hydroxypropyl methylcellulose (HPMC) having a methyl group (MeO) substitution ratio of 15% by weight and a hydroxypropyl group (HPO) substitution ratio of 30% by weight was used as the cellulose ether, and the viscosity of the highly substituted HPMC was 2.0 Was 54,000 cps when measured at 20 DEG C and 20 rpm using a Brookfield viscometer based on the weight% aqueous solution.

Configuration Composition ratio (% by weight) water 18.2 Wetting agent 0.2 Dispersant 0.3 Defoamer 0.2 Cryoprotectant 1.0 Titanium dioxide (Tio ₂ , white pigment) 10.0 Calcium carbonate (CaCO ₃ , extender pigment) 45.0 Talc (extender pigment) 5.0 antiseptic 0.2 PH adjusting agent 0.1 Acrylic emulsion 15.0 Coating formulation 1.5 Methanol 3.0 Cellulose ether 0.3 Sum 100.0

* Wetting agent: CF-10 (Dow)

* Dispersant: Nopcosperse 44S (San Nopco)

* Defoamer: SN Defoamer 313K (San Nopco)

* Anti-freezing agent: Ethylene glycol (purified water)

Titanium Dioxide (TiO ₂ ): Ti-pure R-901 (DUPONT)

Calcium carbonate (CaCO ₃ ): Omyacarb 5T (OMYA)

Talc: KSA-325 (KOCH)

* Preservative: Troysan 174 (Troy chemical)

* pH controller: AMP-95 (ANGUS)

* Acrylic emulsion: AC-261P (Dow)

Coalescing agent: Texanol (Eastman chemical)

* Methanol: Methanol (purified water)

Example  2 to 6 and Comparative Example  1 to 6

An aqueous paint composition was prepared in the same manner as in Example 1, except that the cellulose ether having the substitution ratio and the viscosity shown in Table 2 below was used. However, the viscosity was a value measured under the same conditions as in Example 1. [

Cellulose ether
Kinds Viscosity
(cps) MeO
(weight%) HPO
(weight%) HEO
(weight%) Example 1 Highly substituted HPMC 54,000 15 30 - Example 2 Highly substituted HPMC 54,000 20 26 - Example 3 Highly substituted HPMC 53,000 25 28 - Example 4 Highly substituted HEMC 49,000 24 - 9 Example 5 Highly substituted HEMC 49,000 28 - 9 Example 6 Highly substituted HEMC 48,000 30 - 7 Comparative Example 1 HPMC 55,000 28 9 - Comparative Example 2 HPMC 54,500 10 36 - Comparative Example 3 HEMC 50,000 31 - 7 Comparative Example 4 HEMC 49,000 18 - 15 Comparative Example 5 HEC (regular type) 35,000 - - 48 Comparative Example 6 HEC (bio type) 34,500 - - 62

In Table 2, HPMC stands for hydroxypropylmethylcellulose, HEMC stands for hydroxyethylmethylcellulose, HEC stands for hydroxyethylcellulose, MeO stands for methyl group substitution, HPO stands for hydroxypropyl substitution, and HEO stands for the substitution ratio of hydroxyethyl group.

Example  7

An aqueous paint composition was prepared in the same manner as in Example 1, except that the high substituted HPMC used in Example 1 as the cellulose ether and the HEC used in Comparative Example 5 were mixed in a weight ratio of 1: 1.

Example  8

An aqueous paint composition was prepared in the same manner as in Example 1, except that the high-substituted HEMC used in Example 5 and the HEC used in Comparative Example 5 were mixed as the cellulose ether in a weight ratio of 1: 1.

<Evaluation method>

1. Thickness

The viscosity of the aqueous paint compositions prepared according to Examples 1 to 8 and Comparative Examples 1 to 6 was measured at 23 ° C using a viscometer (Krebs Viscometer from Sheen Instruments Limited), and the results are shown in Table 3 below. It is evaluated that the higher the viscosity value is, the better the thickening efficiency is.

2. Storage stability

The aqueous paint compositions prepared according to Examples 1 to 8 and Comparative Examples 1 to 6 were stored at room temperature for 6 months, and the degree of appearance change was visually observed. At this time, the storage stability was evaluated relative to grade 5 as described below, and the storage stability was evaluated to be better as the change in appearance was smaller. Specifically, the appearance was evaluated as to the degree of layer separation, fungal generation, and degree of viscosity change caused by each aqueous paint composition after the above storage period.

⊚: very excellent, ∘: excellent, △: fair, X: dull, XX: extremely dull

3. Biostability

The endogenous degradability of the cellulose ethers used in Examples 1 to 8 and Comparative Examples 1 to 6 was evaluated. First, each of the cellulose ethers was added to water having a pH of 7 to prepare an aqueous solution having a concentration of 2% by weight, and then the viscosity (V ₀ ) of each of the cellulose ether aqueous solutions was measured. At this time, the viscosity was measured using a Brookfield viscometer under the conditions of 20 ° C and 20 rpm, and the results are shown in Table 2 above. Thereafter, 0.1 ml of an enzyme aqueous solution (enzyme name: cellulase, Sigma-C1184, Sigma-Aldrich, Cellulase from Aspergillusniger) was added to each aqueous solution of the cellulose ether to obtain a mixed solution. Then, each of the above mixed solutions was stirred in a constant temperature water bath at 20 ° C. for 1 hour, and then the viscosity (V _f ) of the mixed solution was measured at 20 ° C. and 20 rpm using a Brookfield viscometer. The endogenous degradability was evaluated by the ratio of the viscosity (V _f ) after the addition to the viscosity (V ₀ ) before the aqueous solution of the enzyme solution. The results are shown in Table 3 below.

Endogenous degradation (%) = (V _f / V ₀ ) x 100 ... (One)

The larger the value calculated according to the above formula (1), the higher the endogenous degradability, and the higher the endogenous degradability, the higher the storage stability.

4. Water resistance

Three tests were conducted to evaluate the water resistance of the aqueous paint compositions prepared according to Examples 1 to 8 and Comparative Examples 1 to 6.

(1) Each of the above water-based paint compositions was applied onto the lower limb (Form 2A of Leneta co.) Using a drawer (REF 100-120 from Sheen Instruments Limited) and dried at 25 캜 for 60 minutes to form a film After water was dropped onto the coating film, after one hour had elapsed, the appearance of the coating film was visually observed. At this time, the water resistance was evaluated according to grade 5 as described below. The smaller the degree of dissolution in the water and the degree of peeling, the better the water resistance.

⊚: very excellent, ∘: excellent, △: fair, X: dull, XX: extremely dull

(2) Each of the aqueous paint compositions was coated on a substrate and dried for 7 days to form a coating film on the substrate surface. Then, the substrate coated with the aqueous paint composition was immersed in water to visually observe the appearance of the coating film. At this time, the water resistance was evaluated as 5 grade as follows. The degree to which the coating film is peeled off and the color change is small means that the water resistance is excellent.

⊚: very excellent, ∘: excellent, △: fair, X: dull, XX: extremely dull

(3) Water resistance of each of the water-based paint compositions was confirmed by using a washability test equipment. Specifically, each of the above water-based paint compositions was applied to a quartz glass plate (45 cm x 45 cm) using a drawer (REF 100-120 from Sheen Instruments Limited), and a room temperature (23 ± 2 ° C) % For 5 days, then heated and dried at 60 占 2 占 폚 for 24 hours, and then cooled at room temperature. Thereafter, the quartz glass plate to which the water-based paint was applied was fixed to a Sheen wet abrasion scrub tester 303, and 1% soapy water (neutral soap solution) was dropped to completely wet the water-based paint application portion on the glass plate . Subsequently, the tester was operated so that the brush mounted on the tester was reciprocated in contact with the water-based paint application portion on the quartz glass plate. At this time, the number of reciprocations of the brush is 45 +/- 5 times per minute, and the number of reciprocations of the brush at the time when the coat of the quartz glass plate in the center of about 15 to 20 cm is worn or peeled off is shown in Table 3 below. At this time, the water resistance means that the greater the number of times, the better the water resistance.

5. Workability

The water-based paint compositions prepared according to Examples 1 to 8 and Comparative Examples 1 to 6 were applied to a slate (slurry of bacilli) using an aqueous roller (aqueous roller of artisan brush). During this coating operation, relatively sensory evaluation was performed on the degree of splashing around the water-based paint composition, the degree of softness upon working with a roller, and the degree of extrusion (degree of strength) applied to the lower legs, and the results are shown in Table 3 below . In this case, the workability is evaluated as 5 grade as follows. The smaller the degree of bouncing, the smaller the degree of strength during the work, and the more workable the work is, the better the workability is.

⊚: very excellent, ∘: excellent, △: fair, X: dull, XX: extremely dull

Thickening
(Paint viscosity, KU) Save
stability Endogenous degradability Water resistance Workability 1 hours 7 days Number of times (times) Example 1 120.1 ○ 54% ○ ○ 1410 ◎ Example 2 120.9 ○ 55% ◎ ◎ 1850 ◎ Example 3 119.5 ○ 53% ○ ○ 1350 ◎ Example 4 117.0 ○ 41% ○ ○ 1400 ◎ Example 5 117.4 ○ 40% ◎ ◎ 1800 ◎ Example 6 117.1 ○ 40% ○ ○ 1370 ◎ Example 7 117.4 ○ 48% ○ ○ 1200 ○ Example 8 116.9 ○ 45% ○ ○ 1250 ○ Comparative Example 1 120.7 X 30% △ △ 920 △ Comparative Example 2 120.2 X 30% △ △ 900 △ Comparative Example 3 118.6 X 25% △ △ 910 △ Comparative Example 4 117.4 X 24% △ △ 920 △ Comparative Example 5 105.8 ○ 50% X X 750 X Comparative Example 6 104.4 ○ 80% XX XX 500 X

Table 3 shows that the water-based paint compositions prepared according to Examples 1 to 8 of the present invention have improved water resistance compared to the aqueous paint compositions prepared according to Comparative Examples 1 to 6.

It can also be confirmed that the aqueous paint compositions of Examples 1 to 8 exhibited similar or better values than the aqueous paint compositions prepared according to the comparative examples in the case of thickening, storage stability, endurance and workability . However, in the case of the aqueous paints of Comparative Examples 5 and 6 using hydroxyethyl cellulose alone as the cellulose ether, the storage stability and the endogenous degradation resistance were excellent, but the water resistance and workability were remarkably low and it was not usable as a waterborne paint for flooring Respectively.

On the other hand, in the case of the aqueous paint compositions prepared according to Examples 1 to 6 which do not contain hydroxyethylcellulose, compared with the aqueous paint compositions prepared according to Examples 7 to 8 containing hydroxyethylcellulose, The results of the water resistance evaluation using the water resistance test were more excellent. Thus, it is possible to provide an aqueous paint composition having better water resistance when it contains no more than one selected from the group consisting of the highly substituted hydroxyethyl methyl cellulose and the highly substituted hydroxypropyl methyl cellulose according to the present invention without containing hydroxyethyl cellulose .

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Should be construed as being included in the scope of the present invention.

Claims (6)

An aqueous paint composition comprising a water-soluble emulsion, a cellulose ether, a pigment and water,
The cellulose ether is a highly substituted hydroxyethyl methylcellulose having a methyl group substitution ratio of 20 to 30% by weight and a hydroxyethyl group substitution ratio of 5 to 10% by weight; Substituted hydroxypropyl methylcellulose having a methyl group substitution ratio of 15 to 25% by weight and a hydroxypropyl substitution ratio of 25 to 35% by weight. The method according to claim 1,
Wherein the cellulose ether does not comprise hydroxyethylcellulose. The method according to claim 1,
Wherein the content of the cellulose ether is 0.1 to 1.0 wt% based on the total weight of the aqueous paint composition. The method according to claim 1,
Wherein the water-soluble emulsion comprises at least one selected from the group consisting of an acrylic emulsion, a vinyl acetate emulsion, a vinyl acetate emulsion, a styrene acrylic emulsion, a water-soluble silicone emulsion and a water-soluble alkyd emulsion. The method according to claim 1,
Wherein the aqueous paint composition further comprises at least one additive selected from the group consisting of a wetting agent, a dispersing agent, a defoaming agent, a cryoprotectant, an antiseptic, a pH adjusting agent, and a film forming aid. An aqueous paint for flooring prepared from the aqueous paint composition according to any one of claims 1 to 5.