JPH02206664A - Water-based gloss coating composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition for interior and exterior finish of buildings, containing a specific weak anisotropic water-soluble resin, titanium oxide, etc., in a specific proportion in a cationic emulsion, excellent in glossiness of films and improved in wettability of pigments with reduced voids in the films. CONSTITUTION:The objective composition, obtained by blending (A) 100 pts.wt. (solid content) cationic emulsion (e.g. acrylic acid ester) with (B) 0.4-2.0 pts.wt. water-soluble resin expressed by formula I [M is monovalent cation; q/p=(1-10)/100] (e.g. copolymer of acrylamide and monovalent metal salt of acrylic acid), (C) 0.4-2.0 pts.wt. water-soluble resin (e.g. Mannich compound) expressed by formula II [R1 and R2 are 1-18C alkyl; n/m is (1-10)/100; X is halogen selected from Cl, Br and I] and (D) 40-150 pts.wt. titanium oxide, excellent in dispersibility and dispersion stability of the titanium oxide, etc., with fluidity and improved in wettability of pigments.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a coating composition with good gloss for use on the interior and exterior of buildings.

(Prior Art) Paints for the interior and exterior of buildings have traditionally been required to have properties such as water-based properties, high gloss, and adhesion to the base.

As for aqueous emulsions, many products using various aqueous emulsions have already been produced.

In order to achieve high gloss, Japanese Patent Application Laid-Open No. 57-73060 describes an aqueous coating composition with excellent gloss and durability that imparts gloss in the low molecular weight portion and durability in the high molecular weight portion by adjusting the molecular weight distribution. It describes how to do this. JP-A No. 57-10657 discloses that a water-based paint with high gloss and good peelability is produced by using a water-insoluble fatty acid ester or phthalate ester as a surface treatment agent. It is stated that the gloss of the coating film is improved by imparting an optical effect.

(Problems to be Solved by the Invention) However, all of these methods have the following problems.

In JP-A No. 57-73060, the weather resistance decreases in the long term due to the presence of a low molecular weight portion. Similarly, JP-A-5
No. 7-10657 uses a fatty acid ester or a phthalate ester, so its weather resistance decreases.

Generally, due to the cationic properties of a cationic emulsion and the anionic nature of the base, the coating film formed from the cationic emulsion is
It is well known that adhesion is improved. However, when making a paint using a cationic emulsion,
Since the surface of titanium oxide or calcium carbonate is anionically charged, poor dispersion occurs when commonly used anionic dispersants are used.

Furthermore, in order to prevent poor dispersion, nonionic water-soluble resins such as hydroxyethylcellulose and methylcellulose or nonionic dispersants are used to form a protective layer on the interface of the cationic emulsion, but there is no ionic interaction. At present, it is difficult to obtain good dispersibility, resulting in poor fluidity of the coating material, and voids are likely to occur in the coating film, resulting in a decrease in gloss, so it has not been possible to achieve high gloss.

(Method for Solving the Problems) As a result of intensive research in order to solve the above problems, the present inventors have developed a cationic emulsion, a specific weakly anionic water-soluble molten titanium oxide, and a specific cationic emulsion. When combined with water-soluble resins, the dispersibility and dispersion stability of titanium oxide and calcium carbonate are excellent, and the viscosity of the paint becomes fluid with dilatancy, improving the wettability of the pigment, so there are fewer voids in the paint film. It was discovered that a high-gloss coating film can be formed. That is, with respect to 100 parts by weight of the cation emulsion as a solid content as the A component, the general formula (1) as the B component: % formula % (However, M: monovalent metal ion, q/p-i ~ 10/100 ) 0.4 to 2.0 parts by weight as a solid content of a water-soluble resin represented by the general formula (I) as the C component: NHNH2 H2 R, R2 (where R,, R2 are carbon atoms of 1 to 18 alkyl group, n/m = 1 to 10/100.X is a halogen atom selected from Cl, Br, and I. The coating composition contains 40 to 150 parts by weight of titanium oxide as component D.

Hereinafter, typical methods for producing components A, B, and C used in the present invention will be illustrated. However, these manufacturing methods do not limit the present invention in any way.

Here, the cationic emulsion of the present invention is produced, for example, by the method of Reference Example 1, but the main monomer constituting this cationic emulsion is 1 in 5 molecules.
The following monomers having one or more polymerizable unsaturated bonds can be used alone or in any combination.

(2) Alkyl esters of acrylic acid or methacrylic acid, such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, and 2-ethylhexyl acrylate.

■Carboxylic acid-containing monomers, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. ■Polymerizable aromatic compounds, such as styrene, α-methylstyrene, vinyltoluene, t-butyl Styrene etc.

■α-olefin compounds, such as ethylene and propylene.

■Vinyl compounds, such as vinyl acetate and vinyl propionate.

■Polymerizable nitriles, such as acrylonitrile and methacrylonitrile.

(2) Polymerizable amides, such as acrylic amide, methacrylic amide, diacetonamide, N-methylol acrylamide, etc.

■Polymerizable amines, such as dimethylamino methacrylate, diethylamino methacrylate, etc. Among these, t1!
In consideration of the weather resistance of the membrane, it is preferable that the raw monomer in the resin is an alkyl ester of acrylic acid or methacrylic acid.

To impart cationic properties to the emulsion during synthesis, copolymerizing a polymerizable amine monomer and cationizing it with dilute hydrochloric acid after polymerization, using a cationic initiator, or adding a cationic surfactant. There are ways to use it.

Next, the water-soluble resin represented by formula (1) -a is generally
It is produced by copolymerization of acrylamide and a metal salt of acrylic acid.

Next, the water-soluble resin represented by the general formula (1) is called a Mannich compound, and is produced by reacting polyacrylamide with formalin, dimethylamine, and an acid or water to cause a Mannich reaction.

The water-soluble resins represented by general formulas (1) and (!) above are known as paper strength agents in the paper manufacturing industry and are used as flocculants for pulp.

Next, the titanium oxide used in the present invention includes, for example, commercially available products such as JR-800 (Teikoku Kako ■), JR-801 (Teikoku Kako ■), R-901 (DuPont), R-931 (DuPont), R-911 (DuPont), R-4E (Sakai Chemical Industry), R-780 (Ishihara Kogyo ■), R-780-
Titanium oxide for emulsion paints belonging to JIS classification R-4 and ASTM classification ■ such as 2<Ishihara Kogyo ■) are good.

Among the above four components, if component B is less than 0.4 parts by weight in solids per 100 parts by weight of the cationic emulsion, the fluidity of the paint will be insufficient and the initial gloss will not be very good. Comparative Example 3) In addition, when the B component is more than 2.0 parts by weight, the initial gloss is good, but since the water-soluble resin component increases in the paint, the weather resistance of the paint film decreases and the gloss decreases over time. do. (Comparative Example 4) q/p is preferably 1 to 10/100, and q/p<4/1
In the case of 00, the anionic property of the water-soluble resin is insufficient and does not protect the cationic emulsion, C4/P>1
In the case of 0/100, the anionic nature of the water-soluble resin is too strong, inhibiting AQ stability, and when A and B are mixed, the mixed system may gel.

If component C is less than 0.4 parts by weight per 100 parts by weight of the solid content of the cationic emulsion, the fluidity of the paint will be insufficient and the initial gloss will not be very good (Comparative Example 3). When the amount is more than 2.0 parts by weight, although the initial gloss is good, the amount of water-soluble resin components in the coating system increases, and the weather resistance of the coating film decreases. Moreover, R, , R2 have 1 to 1 carbon atoms.
If the number of carbon atoms in the 18 alkyl group is larger than this, there will be a problem in the water solubility of the water-soluble resin. Furthermore, n/m is preferably 1 to 10/100, and n,/
m (If n/m is 1/100, the cationic property of the water-soluble resin is insufficient and the C component does not sufficiently protect the titanium oxide of the D component. If n/m is 10/100, the cationic property is too strong and C and When mixed with D, the mixed system may gel.

The amount of titanium oxide used as component D is preferably 40 to 150 parts by weight based on 100 parts by weight of component A, especially 6 parts by weight.
0 parts by weight to 100 parts by weight are preferred. If it is less than 40 parts by weight, the hiding rate of the coating will decrease (Comparative Examples, etc.), 150
If the amount is larger than 1 part by weight, the initial gloss of the coating film will be extremely reduced. (Comparative Example 6) The method of mixing these four components is as follows: (i) A method of adding and mixing a premixed mixture of components A and B to a mixture of components D and C.

(i) A method of adding and mixing a mixture of components C and B that have been mixed in advance to component D, and then adding and mixing component A.

(i) A method of adding and mixing component C to a mixture of components D and B, and then adding and mixing component A.

These can be mixed in any way, but among them (i) provides the best gloss.

(Function) The excellent gloss of the aqueous glossy coating composition of the present invention is due to the fact that the coating film formed after application of the coating material forms a smooth coating surface without generating voids.

In other words, the water-soluble polymer component ionically adsorbs to the pigment, which has an anionic surface due to its cationic nature, improving the wettability of the pigment and forming a smooth coating film, resulting in gloss. will improve.

In other words, although it cannot be definitively determined, the ingredients of the present invention are:
It is assumed that because it acts as a thickener and also contributes to the dispersion of pigments, a smooth coating film is formed.

On the other hand, the anionic water-soluble resin of component B coats the particle surface of the cationic emulsion of component A and becomes a protective colloid, which fills the voids generated by the fusion of the emulsion during coating film formation. It is thought that the surface becomes smoother and the gloss is improved.

The aqueous glossy coating composition of the present invention is prepared by mixing emulsion bases 1 to 1 which are a mixture of A and B and a titanium paste which is a mixture of C and D. When ordinary cationic water-soluble resins and anionic water-soluble resins are used, B and C ionically associate with each other at the stage of mixing the emulsion paste and titanium paste, resulting in an increase in the viscosity of the paint system or during the formation of a coating film. , a problem arises in that voids are formed and the gloss is reduced.

On the other hand, the combination proposed in this patent, namely a Mannich-modified cationic polymer and an acrylamide-based anionic polymer, is so stable that it is used as an agent for paper power generation in the paper industry, and even if the two are directly mixed. ,
Although the viscosity of the mixed system increased, the present inventors found that the above problems could be solved by using these materials, and the present invention was completed.

Although the exact reason why the paint of the present invention is stable is not known, it is likely that the charges on the surface of the emulsion particles and titanium oxide are protected by the polymer main chain of the water-soluble resin, and that each particle is affected by steric hindrance between the polymers. It is speculated that the object cannot be approached beyond the point where it becomes stable and becomes stable.

(Example) Reference example 1. (Method for synthesizing Kanaone emulsion) 60 parts of methyl methacrylate, 13 parts of n-butyl methacrylate
parts, 15 parts of 2-ethylhexyl acrylate, 9 parts of n-butyl acrylate and 1 part of dimethylamine methacrylate.
3 parts of dodecylbenzylammonium chloride and 45 parts of ion-exchanged water were mixed with 100 parts of the mixture with 3 parts of dodecylbenzyl ammonium chloride and stirred with an Ajihomo mixer to emulsify, and then 5% of the mixture (emulsion A) was separated. (The rest is emulsion B.) As an initiator, 2,2-azobis(2-aminodipropane) hydrochloride 0
．． 4 parts were used and dissolved in 5 parts of iodine exchange water. (
This was designated as solution C.) After adding 52 parts of ion-exchanged water in which oxygen was replaced with nitrogen in a separable flask equipped with a stirrer and a nitrogen introduction tube,
The temperature was raised to 70°C, and emulsion A was added. At the same time, 5% of solution C was added. However, the stirrer continued stirring during the reaction. After 1 hour of polymerization, remaining emulsion B and solution C
were added dropwise simultaneously over a period of 3.5 hours.

Thereafter, the temperature inside the reaction vessel was raised to 80°C, and the aging reaction was carried out for 1 hour, and then the reaction vessel was cooled to complete the reaction. Then dilute hydrochloric acid was added. The resulting emulsion had a solid content of 50.0% and a particle size of 0.1 to 0.3 .mu.m.

Reference PA2 (Anion emulsion synthesis method) Reference example 1
An emulsion was synthesized using 3 parts of sodium dodecylbenzene sulfonate in place of dodecylbenzene ammonium chloride, and in accordance with Reference Example 1 for the monomer composition and polymerization procedure. The resulting emulsion has a solid content of 50
．． The 2% particle size was 0.1-0.3μ.

Reference Example 3 (Mannich-modified cationic water-soluble resin) 10 parts of acrylamide was dissolved in a solvent (tertiary butanol/water =
90/10), and 0.3 part of benzoyl peroxide was added as a catalyst. This was added to a separable flask equipped with a stirrer and a nitrogen introduction tube, and after replacing the oxygen in the separable flask with nitrogen, the temperature was raised to 70°C and polymerization was carried out for 3 hours. ) After adding 1 part of sodium phosphate and confirming that the pH of the reaction system was maintained at 10 to 10.5, 0.39 part of formalin was added, and then 0.58 part of dimethylamine was added. This question 1 reaction system is 70℃
After cooling the reaction product, which was maintained at a temperature of 0.0, 0.51 part of HCl (calculated as an active ingredient) was gradually added.

A cationic water-soluble resin was obtained in this way, and the nonvolatile content was 10.4% and the viscosity was 3000 cps/25°C.

Reference Example 4 10 parts of acrylamide was dissolved in a solvent (tertiary butanol/water =
90/10), and 0.3 part of benzoyl peroxide was added as a solvent. This was added to a separable flask equipped with a stirrer and a nitrogen introduction tube, and after the oxygen in the separable flask was replaced with nitrogen, the temperature was raised to 70° C. and heavy metal treatment was performed for 3 hours. In this way, a nonionic water-soluble resin was obtained, with a non-volatile content of 10.0% and a viscosity of 2000 cp.
s/25°C.

Reference Example 5 (Acrylamide-based anionic water-soluble resin) A mixture of 9 parts of acrylamide and 1 part of acrylic acid was dissolved in a solvent (
It was dissolved in tertiary butanol/water-90/1.0>100 parts, and 0.3 parts of benzoyl peroxide was added as a catalyst.

Add this to a separable flask equipped with a stirrer and a nitrogen inlet tube, add it to a separable flask equipped with a nitrogen inlet,
After replacing the oxygen and nitrogen in the separable flask, the temperature was raised to 70°C and polymerization was carried out for 3 hours.

After the reaction, 0.56 part of NaOH is gradually added after cooling.

In this way, an anionic water-soluble resin was obtained, with a non-volatile content of 10.2%.

(Coating preparation method) Example 1 8.66 parts of water and 2.55 parts of cationic water-soluble resin were charged in advance in a tank, and then titanium oxide (19.00 parts) was gradually added while stirring with a disper. A titanium paste was prepared. Add to this an antifoaming agent (0,
After adding 05 parts), the sand mill was bathed. This was designated as titanium paste X. On the other hand, 64.0 parts of an acrylic resin-based cationic emulsion (solid content: 50.0) was placed in a tank, and 2.55 parts of a cationic water-soluble resin were gradually added thereto while stirring with a disper. After stirring for 1 hour after the completion of addition, titanium paste

Similarly, paints of Examples 2 to 5 and Comparative Examples 1 to 6 were created.

(Margin below) Book 1 The paint was measured using a BH type viscometer.

*2 Measure the paint with a BH type viscometer, The ratio of 2rρm/20rp- was taken as the thixotropic coefficient.

*3 The viscosity and thixotropic coefficient were measured after the paint was stored at 50°C for 4 weeks.

*4 Paint 10 mils (0,254v+s) on the glass plate
Apply with applicator and store at 20℃, 65%R for 7 days.
After curing under the conditions of H, the coating film was immersed in water for 3 days, and the condition of the coating film was checked, and those with no blistering or loss of gloss were evaluated as good.

*5 The sample preparation method is JIS 540 according to *4.
It was measured using the specular gloss measurement method (60'/60°) of 06.7.

Book 6 Hiding rate test paper (Japan Paint Inspection Association) with 5 mil (0
, 127 m1) thick, and the coating was kept at 20°C for 3 days.
After curing under conditions of , 65% RH, the Y value was measured with a color difference meter, and the ratio of black part/white part was taken as the hiding rate.

*7 Method for making a test piece*8 Prepare a test piece in accordance with JIS A 6910 Multi-layer Finish Coating Material E.

Bottom (Carp paint + EX sealer (Shikoku Kaken Koryo Co., Ltd. 1t)
l) Main material coating: Lena Friend (!Kokukaken 11 &
For the weather resistance test of the coating composition of the present invention (manufactured by Shikisha Co., Ltd.), JkB was conducted for 2 years according to the method of JIS K 54009.4, and no blistering, peeling, or abnormal decrease in gloss was observed in the coating film. Those with obvious abnormalities in the coating film were marked as ×.

Contamination resistance was visually evaluated by comparing the contamination state of the surface one year after the Ik dew test with that of the preserved sample.

Umbrella 9J[S was tested according to the standard test of 54006.15. The base is GRC board (manufactured by Nippon Sheet Glass Co., Ltd.)
Flexible board (flexible board that complies with JIS A 5403), Rena Friend (main coating material manufactured by Shikoku Kaken Kogyo Co., Ltd.), mortar board (JIS R5201)
A mortar prepared according to the method was used.

For the present IO paint, test pieces were prepared by applying the paints of Examples 1 to 5 and Comparative Examples 1 to 7 with a brush.

The test was conducted according to JIS K 5400 6.15 base opening test, after cutting the coating film with a cutter knife,
After adhering to cellophane tape (manufactured by Chiban), the cello tape was peeled off to check the adhesion between the base and the paint film.

In accordance with the evaluation method of the base grain test, an evaluation score of 10 is the best, with no peeling in the base grain, and an evaluation score of 0 is the lowest, meaning that the area of peeling is 65% or more of the total square area.

The test for 7 paints in JIS Z 291+ mold resistance test method was followed. The test evaluation is based on JIS29114.
3.2 The method for displaying test results was followed.

(Effect) As is clear from Tables 3 and 4, Examples 1 to 5 had
All of them show good results in terms of paint physical properties and coating film physical properties. On the other hand, Comparative Examples 1 to 6 are inferior in both the physical properties of the paint and the physical properties of the coating film, as described above. Specifically, in Comparative Example 1, Anion Emulsion 3 was used in place of the water-dispersible resin Kanaone Emulsion among the components of the composition of the present invention, but the stain resistance and weather resistance were poor, and the gloss was slightly reduced. In Comparative Example 2, a nonionic water-soluble resin was used in place of the anionic and cationic water-soluble resins used as components B and C in the composition of the present invention. The result was that they were inferior in gender. Comparative Example 3 is a case where the amount of the water-soluble resin used as component B and component C among the components of the composition of the present invention is smaller than that of the present invention.
Slightly inferior in initial gloss compared to the present invention. Comparative Example 4 is a case where the amount of water-soluble resin used as component B and component C in the composition of the present invention is larger than that of the present invention, and the water resistance and weather resistance are slightly inferior compared to the present invention. .

Comparative Example 5 is a case where the amount of titanium oxide in the components of the composition of the present invention is smaller than that of the present invention, and the initial gloss is slightly inferior to that of the present invention. Comparative Example 6 is a case where the amount of titanium oxide in the components of the composition of the present invention is larger than that of the present invention, and is inferior in water resistance and initial gloss compared to the present invention. Comparative Example 7 is a formulation of a normal water-based gloss paint, and although it has a normal level of initial gloss, the level is inferior to that of the present invention, and the water resistance is poor due to the influence of the dispersant, and it is difficult to expose. A decrease in physical properties was observed.

In addition, in the examples of the present invention, since a cationic emulsion was used, anti-fouling properties of the coating film due to anti-fungal properties and anti-static properties were also observed.

As described above, it is clear that the aqueous glossy coating composition of the present invention has excellent coating and coating physical properties, and these can only be obtained with its constituent components and numerical ranges.

Claims (3)

[Claims] (1) A cation emulsion as a solid content,
For 100 parts by weight, the general formula (I) as component B: ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (However, M: monovalent metal ion, q/p = 1 to 10/100) The solid content of the water-soluble resin shown is 0.4 to 2.0 parts by weight, and the C component is the general formula (II): ▲There are numerical formulas, chemical formulas, tables, etc.▼(II) (However, R_1 and R_2 are carbon alkyl group of numbers 1 to 18, n/m = 1 to 10/100, X is a halogen atom selected from Cl, Br, and I) in a solid content of 0.4 to 2 0 parts by weight, and 40 to 150 parts by weight of titanium oxide as component D. (2) The aqueous gloss coating composition according to claim 1, wherein the cationic emulsion is a polymer or copolymer of an acrylic ester and a methacrylic ester. (3) A claim in which a titanium paste made by dispersing titanium oxide in a water-soluble resin represented by general formula (II) is added to a cationic emulsion and a water-soluble resin represented by general formula (I) subjected to an ion reaction. Item 1. A method for producing an aqueous glossy coating composition according to item 1.