JPS6372764A - Thickened latex composition for coating - Google Patents

Abstract

PURPOSE:To provide the title compsn, which contains no water-soluble high- molecualr material, scarecely emits odor, has excellent viscosity stability and low-temperature film-forming properties and gives a coating film having good water resistance, consisting of a specified arcylic polymer latex, an org solvent and a petroleum hydrocarbon solvent. CONSTITUTION:An alkyl (meth)acrylate is emulsion-polymerized with 1-8wt% ethylenically unsaturated carboxylic acid (e.g., acrylic acid) in the presence of a radical polymn. catalyst in an aq. medium contg. a surfactant to obtan an acrylic polymer latex (A) having a particle size of 0.05-0.5mu. The component a is blended with 5-20pts.wt. (per 100pts.wt. polymer) org. solvent (B) having a b.p. of not lower than 120 deg.C (e.g., butyl cellosolve) other than hydrocarbon solvents and 20-60pts.wt. petroleum hydrocarbon solvent (C) having an aniline point of not lower than 25 deg.C (e.g., mineral sprit) to obtain a coating latex compsn. which contains no water-soluble high-molecular material and has the lowest film-forming temp. of not higher than 5 deg.C and a viscosity of not lower than 200,000cps.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a thickened coating latex that has little odor, has excellent viscosity stability, low-temperature film forming properties, and forms a film with excellent water resistance. This relates to a composition, and a mixture of this composition and aggregate is useful as a material for aesthetic finishing of buildings. [Prior Art and Problems] Aqueous dispersion of polymer particles Latex is widely used in various industrial applications such as paints, adhesives, pressure-sensitive adhesives, paper processing agents, and textile processing agents. Acrylic polymer latexes prepared mainly from acrylic esters and methacrylic esters are used in large quantities as binders for building paints and finishing materials due to their excellent weather resistance. The thickened latex is blended with aggregates such as natural sand, stone, glass peas, or synthetic materials, and then painted using a plastering trowel.The aggregate arare finish reveals the beautiful colors and three-dimensionality of the aggregate. Compared to ordinary paints and finishing materials, it is possible to create a much more luxurious finish.

The aggregate grain size of the aggregate gravy finish such as and is large,
Since the coating thickness is more than /wa and it is often applied with a plastering trowel, the latex called pine dart needs to be adjusted to a very high viscosity, ranging from 200,000 to over 1,000,000 yen. 0 The most common method for thickening latex is the addition of water-soluble polymers. Typical water-soluble polymers include polyvinyl alcohol, methylcellulose, hydroxyethylcellulose, sodium polyacrylate, polyethylene glycol and its modified products, polyvinylpyrrolidone, and alkali-soluble acrylic polymers, which are used in aqueous solutions. By the way, when latex containing these water-soluble polymers is dried,
Water-soluble polymers that lack compatibility with polymers accumulate at the fused interface of polymer particles, and combined with the fact that the original water-soluble polymers are inherently highly sensitive to water, even in small amounts, e.g. On the other hand, even if it is added in an amount of about Q,/%, the water resistance of the dried film is significantly reduced. Poor water resistance means that when exposed to rain, the coating may soften and swell, causing problems such as blistering or peeling, or become cloudy, resulting in serious defects such as a significant loss of aesthetic appearance.

There is a solvent thickening method as an alternative thickening method to the method using water-soluble polymers. An example of this is the Tokuko Sho 1-2711
T issue, Tokuko Akira! --There is a method disclosed in Kou No. 3100. Solvent thickening is a method in which an organic solvent is added to latex to swell the polymer particles, increase the dispersoid concentration, and increase the interaction force between the particles.

The addition of this organic solvent not only increases the viscosity but also functions as a film-forming aid that lowers the minimum film-forming temperature of the latex. Examples of organic solvents include relatively high boiling point solvents such as c-1, ester, ketone, and aromatic hydrocarbon solvents, but in reality, toluene, xylene, or aromatic hydrocarbon content A high aniline point and a low Ishibari solvent is used.

This is because the coating thickness is thicker than 1m as in this application.
This is because when such a large solvent, which has excellent volatility, remains in the film for a long period of time, it plasticizes the polymer, making it easier for dirt to adhere to it, and also impairs water clouding resistance.

By the way, a serious problem in the case of solvent thickening is that the viscosity of the latex tends to change over time. Therefore, a water-soluble polymer is added as a protective colloid to improve viscosity stability. The above-mentioned examples also contain both an organic solvent and a water-soluble polymer, and the water resistance of the coating has not been fundamentally improved.

Another drawback of aromatic solvents and petroleum solvents with low IJ points is that they have a high odor and toxicity, and there is a strong need to improve the working environment.

On the other hand, when using latex for aggregate hail finishing purposes (hereinafter simply referred to as "this purpose"), it is necessary to set the glass transition temperature of the polymer high in order to ensure the stain resistance of the formed film.
, the minimum film forming temperature of the latex before adding a solvent is necessarily higher than room temperature, usually 2! 'C or higher, preferably
a j j ”C or higher. However, since the latex composition for coating for this purpose is dried and formed into a film in a natural environment, the minimum film formation temperature must be set in consideration of the cold season. It is necessary to keep the temperature below J℃.Aromatic solvents and petroleum solvents with a low A = 177 have the effect of increasing the viscosity and lowering the minimum latex film forming temperature as film forming aids. Since these solvents are highly volatile, they have little effect on lowering the film-forming temperature, and it is necessary to use an excessive amount of K to achieve the target minimum film-forming temperature.As a result, the stability of the latex may decrease, odor, and toxicity may occur. The current situation is that the result is even worse.

[Means for solving problems]

The present inventors have completed the present invention as a result of intensive studies to overcome these current problems. In other words, the present invention provides (6) an ethylenically unsaturated carboxylic acid in the polymer component;
(I3) An organic solvent with a boiling point of 720°C or higher (excluding hydrocarbon solvents), (Q) An aniline point of 2j°C or higher. A thickened coating that is composed of a petroleum-based hydrocarbon solvent with a minimum film-forming temperature of 100,000 centipoise or higher and substantially free of water-soluble polymers. The present invention relates to layered latex compositions.

First, among the requirements constituting the present invention, the polymer of acrylic polymer latex is synthesized from monomers mainly consisting of acrylic acid alkyl ester and methacrylic acid alkyl ester, and the monomers include: Examples include ethyl acrylate, butyl acrylate, hexyl acrylate, coethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and butyl methacrylate.

In addition, ethylenically unsaturated monomers other than these acrylic monomers, such as aromatic monomers such as styrene, vinyltoluene, and α-methylstyrene, acryl tetranitrile,
Vinyl cyanides such as allyl methacrylate, vinyl esters such as vinyl acetate, vinyl propionate, vinyl persate, etc. can also be used within the range of not exceeding 1 SO in the polymer. However, among these aromatic monomers, up to 70 weight S can be used, although the weather resistance decreases as the amount increases. Also,
Furthermore, monomers with various functional groups, such as glycidyl acrylate, glycidyl methacrylate, acrylic@cohydroxyethyl, cohydroxyethyl methacrylate, acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide-N- Ptoxymethylacrylamide, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, N-butoxymethylacrylamide, methacrylic acid phosphooxyethyl, methacrylic acid 3-chloroj-acid phosphooxyprivyl, methylpropanesulfonic acid acrylamide, divinylbenzene, Allyl acrylate, allyl methacrylate, ethylene glycol acrylate, ethylene glycol methacrylate, polyoxyethylene diacrylate, polyoxyethylene dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, sodium styrene sulfonate,
Dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, sodium vinyl sulfonate
Sodium furkylaryl sulfosuccinate and the like can also be added as desired. Among these, unsaturated acid amides such as acrylamide and methacrylamide increase the viscosity of the polymer latex, so they contain 0.0% in the monomer. /
, - weight is preferably used in the range of 1.

The acrylic polymer latex of the present invention is produced by emulsion polymerization methods well known in the art.

That is, it is a method in which a monomer is added to an aqueous medium containing a surfactant, and polymerization is stably performed using a polymerization catalyst that generates radicals.
It is stably dispersed in an aqueous medium as particles with a size of s microns and exists in nine states. Examples of the surfactants used include fatty acid soaps and alkyl sulfones! m, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate,
There are anionic surfactants such as polyoxyethylene alkylaryl sulfate, and nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene sorbitan fatty acid ester, and oxyethylene oxypropylene block copolymer. .

The amount of surfactant added is usually 0,j relative to the monomer.
-Hiro weight %. The polymerization catalyst is one that causes addition polymerization of monomers through radical decomposition using heat or reducing substances, and water-soluble or oil-soluble persulfates, peroxides, azobis compounds, etc. are used. . Examples include potassium persulfate, ammonium persulfate, sodium persulfate, hydrogen peroxide, t-butyl octadrobaroxide, t-butyl peroxybenzoate, j,2-azobisisobutyronitrile, co-azobis( -monamidinopropane) hydrochloride, co-, λ-azobis (co-dimethylvaleronitrile), etc., and the amount thereof is usually 0.1 to 1% by weight based on the monomer. If acceleration of the polymerization rate or polymerization at a lower temperature is desired, IK is used in combination with a polymerization catalyst and a reducing agent such as sodium bisulfite, ferrous chloride, ascorbate, or Rongaritz 11. In addition to these, various polymerization modifiers may be added to the latex during emulsion polymerization and after polymerization as desired, such as sodium hydroxide, potassium hydroxide, ammonia, sodium carbonate, sodium hydrogen carbonate, and hydrogen phosphate. - Regulators such as sodium, disodium hydrogen phosphate, chelating agents such as ethylenediaminetetraacetic acid and its salts, and chain transfer agents for adjusting the molecular weight of the polymer.

The minimum film forming temperature of this acrylic polymer latex is
″C or higher. Minimum latex acid ll1
111 degrees is close to the glass transition temperature of the polymer on the particle surface, but if the temperature is less than 25 degrees Celsius, the formed film will have insufficient stain resistance, and dirt will gradually adhere in the natural environment.
The aesthetic appearance is damaged. Next, the latex must contain /-1% by weight of ethylenically unsaturated carboxylic acid in its polymer components. If this amount is less than 1% by weight, the amount of solvent required to increase the viscosity to the desired level will be excessive, and the stability of the thickened latex will be insufficient.

Moreover, if this amount exceeds 1% by weight, the water resistance and alkali resistance of the coating will be impaired. Note that the amount of this ethylenically unsaturated carboxylic acid defines its proportion in the total polymer. Therefore, if the emulsion polymerization is divided into one or more stages, t
It is also possible to partially introduce an acrylic polymer containing an unsaturated carboxylic acid in an amount exceeding 1, or an acrylic polymer containing less than 7% by weight, and the proportion in the total polymer falls within this range. It is good if it is in Examples of ethylenically unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, anhomaleic acid, and the like. Among these, acrylic acid and methacrylic acid are particularly preferably used.Next, 1.Non-hydrocarbons having a boiling point of 10°C or higher, preferably /rO"C or higher, to be blended into this acrylic polymer latex. , an organic solvent (hereinafter simply referred to as a non-hydrocarbon organic solvent) is necessary for improving the low hybridization film properties of Fi Miratex, so it is necessary to improve the low hybridization film properties when the boiling point is less than 1 O''C. is difficult.

n-7 methyl alcohol, isoamyl alcohol, n-hexanol, methyl amyl alcohol, coethylbutanol, n-heptatool, --heptatool, 3-heptatool, n-ocfi/-ol, coethylhexanol, cyclo Hexanol, benzyl alcohol, furfuryl alcohol, n-butyl ether, diisoamyl ether, n-butylphenyl ether, ethyl benzyl ether, methyl-n-butyl ketone, methyl-n-
amyl ketone, methyl-n-hexyl ketone, ethyl-
n-Butyl ketone, diisobutyl ketone, diacetone alcohol, cyclohexanone, methylcyclohexanone, n-butyl acetate, n-amyl acetate, isoamyl acetate, methylisoamyl acetate, methoxybutyl acetate, coethylbutyl vinegar, coethylhexyl acetate , cyclohexyl acetate 1 Methylcyclohexyl acetate, benzyl acetate, n-butyl propionate, isoamyl propionate, n-butyl D acid, ethyl acetoacetate, ethyl acetoacetate, methyl benzoate, ethyl benzoate, butyl benzoate, benzoate Isoamyl acid, benzyl benzoate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, butyl benzyl phthalate, diptyl adipate, dioctyl adipate, tributyl phosphate, tributoxyethyl phosphate , co, co, dartrimethyl to 3-bentanediol, co, λ, IA-trimethyl 7.3-bentanediol monoisobutyrate, co-. Tartrimethyl!
.

3-bentanediol diisobutyrate, methyl cellosolve, ethyl cellosolve, cellosolve acetate, methyl cellosolve acetate, butyl cellosolve, butyl cellosolve acetate, dibutyl cellosolve, phenyl cellosolve, -monoethylhexyl cellosolve, ethylene glycol monophenyl ether acetate, hexyl cellosolve, Methylcarpitol, carpitol, carpitol acetate, butylcarpitol, butylcarpitol a7f-), J-ethylhexylcarpitol,
These include butyl tetrahylene glycol, butylpropylene diglycol, hexyl glycol, and hexyl diglycol. Among these, representative organic solvents preferably used include:

Co, dartrimethyl/, J-bentanediol monoisobutyrate, butyl cellosolve, phenyl cellosolve,
-monoethylhexyl cellosolve, butyl carpitol,
Examples include λ-ethylhexylcarpitol.

Next, the petroleum-based hydrocarbon solvent to be blended into this acrylic polymer latex must have an Ayu-13 temperature exceeding 2 DaC. When the aniline point is 25° C. or lower, the viscosity of the thickened latex tends to change over time, which is a serious drawback, and the problem is that it has a strong odor. An example of a petroleum-based hydrocarbon solvent with an aniline point exceeding 5°C is "A-Tsuru" manufactured by Nippon Oil Co., Ltd.
(Aniline point: <<s, t"c), r K crane"
(Aniline point: 3z3℃), "Hyaromco sJ (
Aniline point: us, r"c>, r Mineral spirit A" (Aniline point: ri≦, J"C), Exxon Naphtha Nu !J (aniline point:
53℃), [ExolDuOJ (aniline point = tr
°C), "Pegasol AN-μ" manufactured by Mobil Oil Co., Ltd.
S'' (aniline point: reference φ°C), ``Pegasol 3o da oJ (aniline point: 34°C) 1 Shell Kagaku Co., Ltd. rLAWsJ (aniline point: us, a'c),
Examples include Scherzl D41J (aniline point: 69°C), Scherzl D40J (aniline point near 2°C), and Mineral Spirit KCJ (aniline point: 62°C).

Here, there is no limit on the amount of solvent added to the acrylic polymer latex, but this is because it varies depending on the minimum film forming temperature and desired viscosity of the acrylic polymer latex used. However, when a standard latex is used for this application with the lowest film forming temperature uO''C1 polymer concentration!0%, the polymer lo.

The amount of non-hydrocarbon organic solvents with a boiling point of 1-0''C or higher per part by weight is !N20 parts by weight, and the amount of petroleum-based hydrocarbon solvents with an aniline point of over 2s°C is 20-40 parts by weight. In the present invention, even if a petroleum hydrocarbon solvent with an aniline point exceeding 2 jr 'C is mixed with toluene, xylene, or a petroleum solvent with an aniline point below 25°C, the aniline point of the mixed solvent will be 13. ℃ or more is acceptable.

When adding a non-hydrocarbon organic solvent with a boiling point of 20'C or higher and a petroleum hydrocarbon solvent with an aniline point of over 2j''C to latex, these may be added to the latex, but surfactants The method of emulsifying and dispersing and adding to an aqueous solution is preferable because it allows for uniform and stable mixing in a short time.The surfactant used in this process is appropriately selected from the examples listed above. The appropriate concentration of the solvent in the emulsion is 5 to 75% by weight.

Next, the thickened latex composition for painting of the present invention is
The minimum film forming temperature is 3° C. or lower, the viscosity is 200,000 centipoise or higher, and substantially no water-soluble polymer is allowed to be included. Since this composition is used in a natural environment throughout the four seasons, the minimum film formation temperature F
The temperature must be below ij''C.Designs exceeding ij''C often cause poor film formation depending on the situation even when the temperature is above the minimum film formation temperature of the composition, and the adhesion with the aggregate and substrate may deteriorate. The force is not developed and the problem of peeling occurs. A minimum film forming temperature of 5° C. or less can be achieved by appropriately blending the one type of solvent mentioned above. In addition, the viscosity needs to be 200,000 centipoise or higher; if it is less than 200,000 centipoise, the coating thickness will be
This is due to the fact that K sagging occurs due to the use of aggregate with a large particle size, and the coating workability is poor.As mentioned above, the fact that it does not substantially contain water-soluble polymers makes it water resistant. This is to prevent a large decrease in

However, water-soluble oligo i- which is inevitably generated in the aqueous phase during the emulsion polymerization process is excluded from the scope of water-soluble polymers. If this oligomer occurs to an extent that is undesirable for water resistance, it can be removed from the polymer latex by ultrafiltration.

〔Effect of the invention〕

According to the present invention, it is possible to obtain a latex composition that forms a film with little odor, excellent viscosity stability and low-temperature film formation properties, and excellent water resistance as an aggregate hail finish eyebrow binder. EXAMPLE Next, the present invention will be specifically explained by showing an example and a comparative example, but it goes without saying that the scope of the present invention is limited only to these examples.

In addition, in the example 0 in which parts and % are expressed by weight, various evaluations were performed by the following methods.

Measurement of minimum film forming temperature Measured using a temperature gradient type minimum film forming temperature measuring device (manufactured by Takabayashi Rika Co., Ltd.) Leave at room temperature for 2 hours. Next, the package is opened and the degree of odor is determined by a sensory test. It was ranked into three levels: 01Δ and X depending on the degree of off-odor and malodor.

Evaluation of low-temperature film formation properties After leaving the container containing the latex composition in a cold room kept at a temperature of 3°C for more than 2 hours, the latex composition was deposited on a clean glass plate in the same room to a thickness of 250 microns. Rinse with a uniform Kik cloth and dry.

A turtle that forms a transparent continuous film with no cracks is rated 01, and a large one is rated x.

Measuring Viscosity After leaving the container containing the latex or thickened latex composition in a room at 20°C for at least 1 hour, use a Brookfield rotary viscosity needle (manufactured by Tokyo Keiki Co., Ltd.; BS type 9 rotation speed). Put the latex composition into a glass container of 〇 roocc whose viscosity was measured by turning)
t”cxr time~jO”c×! 1. Temperature cycle tester that can convert time and temperature. ◎Then, measure the viscosity after leaving it in a room at λO''C for a period of λ.If the retention rate for the viscosity before the test exceeds 60%, it is considered to be good without any practical problems. Those with a retention rate of 60% or less, agglomeration, or separation of water are not acceptable.

Evaluation of water whitening resistance Thickened latex was applied to an asbestos slate board with a thickness of about -10 m.
After coating at a ratio of g/d, a coating composition prepared by uniformly kneading 3.2 parts of the same thickened latex composition and 1 part of Kinka gravel No. 7 IT was applied to a thickness of 3° C.m using a metal trowel. -0℃
, tj%R,H, after drying for 3 days indoors at -0°C.
The whitening and softening state of the film was observed when the film was immersed in 11C2 water for 11 hours. A sample with no whitening or softening was graded as O. A sample with slight whitening was graded as Δ, and a sample with marked whitening and a large degree of softening was graded as x.

Evaluation of Water Resistant Adhesion Paint the concrete supplementary board in the same manner as in the water whitening test, and after 7 days of drying, apply epoxy to the painted surface using the Ministry of Construction Building Research Institute adhesion tester (manufactured by Takabayashi Rika Co., Ltd.). Glued with resin and after 26 hours soaked in water,
After 2 hours, the adhesive strength was measured. Adhesive strength is r K9
Anything over /- is a practical problem.
Books in the Ky/cd range are acceptable, but those less than 3 to 9/- tend to cause peeling problems and are not acceptable.

Example/ 250 parts of deionized water and 1 part of ammonium persulfate OJ are charged into a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer, and the internal temperature is adjusted to 1.
Methyl methacrylate ljO parts, styrene sos% n-butyl acrylate/7! 821 parts of acrylic, 35 parts of "Emulgen Q2O" (polyoxyethylene nonylphenyl ether; Kao soap) Nocoj% aqueous solution, 70 parts of "Kol NCJ (sodium polyoxyethylene nonylphenyl sulfate; Kao soap)" Hydrogen 2) IJ
Umko, 3 parts, ammonium persulfate 45 parts and water -1
1 part of the force monomer emulsion is poured in over 3 hours.

During this time, keep the temperature constant at 10°C. When the emulsion has finished flowing in, the temperature is raised to jS°C, and after 7.3 hours have elapsed, it is cooled to 30°C or less. And the liquid... is q, z
K amount of 21% aqueous ammonia solution and then a portion of antifoaming agent (SN Deformer 3r/; San Nopco) were added and the resulting contents were taken out through a 10 mesh strainer. Thus, the polymer concentration is 30% and the viscosity J:
000 centipoise (hereinafter, centipoise is abbreviated as EPA) and an acrylic polymer latex having a minimum film formation temperature of 3J°C was obtained. This will be referred to as latex A hereinafter.

Next, 100 parts of this latex A was charged into a double-arm mnegoo, and while stirring, the solvent emulsion (a) L/ in Table 1,
, were added over 10 minutes, and then the mixture was further added for 0 minutes to obtain an acrylic polymer latex composition having a viscosity of 9 million epl. As a result of carrying out various tests and evaluations on this composition, it was confirmed that it was good in all K items listed in the table, and was excellent as a binder for this purpose.

Example λ In the same manner as in Example 1, 1 latex A/l:) (1 part was mixed with 1 part of the solvent emulsion (b) JO in Table 7 to obtain a latex composition. This was evaluated with K. As a result of implementing the above, as listed in Table 2, all K items were good.
It was useful as a binder for this purpose.

Comparative Example/Same as Example 1, 100 parts of latex A and 0 parts of solvent emulsion (c) were mixed to obtain a latex composition. As shown in Table Jk, this composition had poor low-temperature film formability and also had insufficient water-resistant adhesive strength.

Comparative Example Similarly to Example 1, 100 parts of 1 Latex A and 704 parts of solvent emulsion (d) were mixed to obtain a latex composition.

This composition is l! As shown in JK, it had a bad odor and poor viscosity stability, making it unusable for practical use.Comparative Example 3 Similarly to Example 1, 100 parts of 1 latex A was added with partially saponified polyvinyl alcohol (Nippon Gosei Chemical Co., Ltd.). /j% aqueous solution 1 of Koh-7nol GH20, degree of saponification t≦, tNr9%)
．． A latex composition was obtained by adding 3αS parts of solvent emulsion (d) and adding 3αS parts of solvent emulsion. As a result of evaluating this composition, as shown in Table 3, the viscosity stability was good, but the water whitening resistance and water resistant adhesive strength were poor.

Example 3 A latex composition was obtained in the same manner as in Example 1, except that the solvent emulsion (, ) was used. Incidentally, the aniline point of the petroleum hydrocarbon solvent mixture using the molten emulsion (s)K is 29°C as measured by the method prescribed by JIS K2 CojGK. In the evaluation of this composition, as shown in Table 2, although a slight odor was felt, all the parameters of the composition were good and it could be put to practical use.

Example 3 3 parts of deionized water and 0.3 parts of ammonium persulfate are charged into a reaction vessel similar to that in Example 2, and the internal temperature is brought to 10°C. This contains methyl methacrylate rzz parts, coethylhexyl acrylate 740 parts, methacrylic acid xj parts,
20 parts of Ninykolj≦4J (polyoxyethylene nonylphenyl ether; Nippon Nyukazai), part of Aerosol 0T-7jJ (sodium dioctyl sulfosuccinate; American Cyanamid), 0.7 part of ammonium persulfate, and deionized water. A monomer emulsion consisting of 0.2 parts is allowed to flow in over a period of 43 hours. After finishing the influx 3
After 0 minutes, a monomer mixture consisting of 730 parts of methyl methacrylate, 75 parts of coethylhexyl acrylate, 72.5 parts of acrylic acid, and 1 part of acrylic acid, and 0.7 part of ammonium persulfate were added to 39 parts of deionized water. .3 parts of a catalyst aqueous solution was introduced from a separate dropping tank over a period of 43 hours for the monomer mixture and for 11 hours for the catalyst aqueous solution. During this time, keep the temperature constant at 10°C. 25 after finishing the influx
℃, then 1. Cool to 30℃ or less after j hours have passed 0 and 1 The amount of -9.5 2
5% ammonia aqueous solution, then antifoaming agent (SN defoamer)
After adding a portion of Mar 3117 (San Nopco), the resulting contents were taken out through a 10 mesh strainer. Thus, the polymer concentration is 50% and the viscosity is /! , 000 centipoise (hereinafter, centipoise is abbreviated as EPA) and a minimum film formation temperature of SO″C was obtained. This will be referred to as latex B hereinafter.

In the same manner as in Example 1, 100 parts of latex B were mixed with 3 parts of solvent emulsion (b) shown in Table 1 to obtain a composition with a viscosity of 9,000 epl. This composition was evaluated and as shown in Table 1, it was found to be good in all K items, and was confirmed to be excellent as a binder for one-piece use.

Comparative Example 4 30.5 parts of the solvent emulsion (d) in Table 1 was blended with 100 parts of the latex B of Example 4 to obtain a composition with a viscosity of 1.2 million cps. As a result of evaluating this composition, as shown in Table 3, it had poor odor and viscosity stability, and was found to be unsuitable for practical use.

Below is a margin comparison example! Example Hiro's Latex B 100 parts 1 hydroxyethyl cellulose (union carbide; Cellosize QP-
A latex composition was obtained by adding J parts of a 3% aqueous solution of HIROOOH) and then mixing with a solvent emulsion (d) J 03w6. As a result of evaluating this composition, as shown in Figure 3, although the viscosity stability was good, the water whitening resistance and water resistant adhesive strength were poor.

Example! 3 parts of deionized water and 0.3 parts of ammonium persulfate are charged into a reaction vessel similar to that in Example 1, and the internal temperature is brought to 10°C. In this, methyl methacrylate j Hirobe, acrylic acid-
9 parts of mono-ethylhexyl, 7 parts of methacrylic acid, 7 parts of acrylamide, 2 parts of "Dinicol j4≦" (polyoxyethylene nonylphenyl ether; Nippon Nyukazai) / λ part,
"Aerosol 0T-7sJ (dioctyl sulfosuccinic sodium; American Cyanamid) 7.6 parts,
A monomer emulsion consisting of O, II parts of ammonium persulfate, 1, J parts of disodium hydrogen phosphate and 101 parts of deionized water is run in over a period of 1 hour. 30 minutes after finishing the influx
After minutes, methyl methacrylate/73 parts, acrylic acid λ
-Ethylhexyl 17! K, a monomer mixture consisting of 2 parts of methacrylic acid and an aqueous catalyst solution prepared by dissolving 1 part of ammonium persulfate in 1 part of deionized water saw in separate dropping tanks;
The monomer mixture is allowed to flow in for 2.5 hours, and the aqueous catalyst solution is allowed to flow in for 2.5 hours.

During this time, the temperature was kept constant at ro℃. After finishing the inflow, tj''
Raise the temperature to C, then 1. After j hours have passed, cool to room temperature or below. Then, add 2 parts % ammonia aqueous solution in an amount equal to 9.3 parts of the liquid, then add 1 part of antifoaming agent (SN Deformer Jl/; San Nopco), and pass through a 10-mesh strainer to generate the product. The contents were taken out. As a result, the polymer concentration is 57%, the viscosity is 12,000 centipoise (hereinafter, centipoise is abbreviated as eps),
An acrylic polymer latex having a minimum film forming temperature of +/°C was obtained. This will be referred to as latex C hereinafter.

In the same manner as in Example 1, xr parts of the solvent emulsion (b) shown in Table 1 were blended with 100 parts of latex C to obtain a composition with a viscosity of luer cps. As a result of evaluating this composition, it was found to be good in all items as shown in Table 1, and was excellent as a binder for this purpose.

(The following is a blank space) (2) To prepare a solvent emulsion, mix each compound and emulsify with a homomixer (rotation speed: oootpl>).

/) J, J, 4'-trimethyl 3-bentanediol monoisobutyrate (manufactured by Chisso)

Claims (1)

[Claims] (1) (A) An acrylic polymer latex containing 1 to 8% by weight of ethylenically unsaturated carboxylic acid in the polymer component and having a minimum film formation temperature of 25°C or higher, (B) An organic solvent with a boiling point of 120°C or higher ( (Excluding hydrocarbon solvents); (C) petroleum-based hydrocarbon solvents with an aniline point exceeding 25°C; A thickened latex composition for painting, characterized in that it does not contain a water-soluble polymer.