JP2775349B2 - Emulsion copolymer for floor gloss composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulsion copolymer for a floor gloss composition which exhibits high gloss and is excellent in durability, recoatability, workability and coating film removability, and a floor gloss containing the same. Composition.

[0002]

2. Description of the Related Art A floor gloss composition has good work stability at the time of application, and a coating film obtained by drying shows a high gloss, and a black heel mark or a scuff mark by walking shoes. It is hard to adhere and has excellent durability against the adhesion of dirt such as resin and dust. In addition, it retains its luster when it is cleaned with ordinary detergents, but when it becomes very dirty or damaged, it becomes an alkaline release agent. Therefore, it is required that both the detergent resistance and the property of removing the coating film, which are easily removed, are compatible with each other.

[0003] Conventionally, for the purpose of achieving these requirements, an emulsion copolymer has been used in combination with a polyvalent metal ion or a polyvalent metal complex. The floor gloss composition obtained by this method has a high coating film strength due to so-called metal crosslinking in which the carboxyl groups present in the emulsion copolymer are crosslinked via polyvalent metal ions, and has a black heel mark resistance. This is effective in that the durability is improved, and that the coating is easily removed by dissociation of the metal crosslinks by the alkaline remover.

[0004] However, in order to improve the gloss, the floor gloss composition is usually further applied from the top of the coating film. However, usually, the emulsion copolymer and the polyvalent metal ion or the polyvalent metal complex are not coated. The floor gloss composition is adjusted to a weak alkalinity with ammonia or amine for the purpose of coexisting stably. As a result, the surface of the coating film is roughened, and the workability and the improvement of the glossiness by recoating are deteriorated.

On the other hand, as disclosed in JP-B-62-4051, an emulsion copolymer produced by multi-stage polymerization has been used for a floor gloss composition. This emulsion copolymer has plasticity (glass transition temperature of 0 ° C. or lower) using a crosslinked rubbery copolymer as a core layer for the purpose of improving film formability.

However, when the emulsion copolymer thus obtained is used in a floor gloss composition, the resulting coating film is too soft, and there has been a problem that shoe marks and the like are easily formed.

[0007]

As described above, in the prior art, it has not been possible to sufficiently achieve both the recoating property, the workability and the removability of the coating film.

Accordingly, the present invention provides an emulsifying copolymer for a floor gloss composition which provides a floor gloss composition having high glossiness, excellent durability, and excellent recoatability, workability and coating film removability. It is an object of the present invention to provide a floor gloss composition having excellent performance, which contains the emulsion copolymer and the emulsion copolymer for floor gloss composition.

[0009]

Under such circumstances, the present inventors have conducted intensive studies, and as a result, in the first step, a specific monomer mixture containing no carboxyl group was emulsion-copolymerized to obtain an emulsion copolymer. After the union is obtained, it is found that if the specific monomer mixture containing a carboxyl group is emulsion-copolymerized in the second stage in the presence of the emulsion copolymer, the above problem can be solved, and the present invention is completed. Reached.

That is, according to the present invention, in the first step,
Non-crosslinkable monomer mixture (A) containing no α, β-unsaturated carboxylic acid and containing 40 to 60% by weight of an aromatic vinyl compound
To obtain an emulsion copolymer. In the second step, in the presence of the emulsion copolymer, 10 to 30% by weight of an α, β-unsaturated carboxylic acid and 40 to 60% by weight of an aromatic vinyl compound %
The present invention provides an emulsion polymer for a floor gloss composition obtained by emulsion-copolymerizing a non-crosslinkable monomer mixture (B) containing the same, and a floor gloss composition containing the same.

In the emulsion polymer for floor gloss composition of the present invention, since the aromatic vinyl compound has a high refractive index, it is possible to improve the glossiness of a coating film obtained by using the polymer. it can.

In the copolymerization reaction of the first and second stages, the amount of the aromatic vinyl compound used depends on the amount of the monomer mixture (A).
And (B) 40 to 60% by weight (hereinafter simply referred to as%
). If the amount used is less than 40%, sufficient gloss cannot be obtained, and if it exceeds 60%, the film formability is reduced,
Performance such as glossiness, recoatability, and workability is reduced.

Here, the aromatic vinyl compound includes styrene, o-methylstyrene, m-methylstyrene, p-
Examples include methylstyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene and the like.

In the emulsion copolymer for floor gloss composition of the present invention, the non-crosslinkable monomer mixture (A) used in the first stage copolymerization reaction contains α, β-unsaturated carboxylic acid. It is necessary that the non-crosslinkable monomer mixture (B) used in the second-stage copolymerization reaction not contain the α, β-unsaturated carboxylic acid. When the non-crosslinkable monomer polymer (A) used in the first-stage copolymerization reaction contains α, β-unsaturated carboxylic acid, the coating film becomes weakly alkaline floor gloss composition in the recoating operation stage. By applying an object, the coating film is easily swollen, the strength of the coating film is reduced, and the surface of the coating film is roughened by the force of a mop or the like, and the gloss is reduced.

The amount of α, β-unsaturated carboxylic acid used in the non-crosslinkable monomer mixture (B) used in the second stage copolymerization reaction is in the range of 10 to 30%. If the amount used is less than 10%, the metal crosslinking by the carboxyl group and the metal ion or metal complex is not sufficient, so that the strength of the coating film decreases and the
If it exceeds, the removability of the coating film is improved, but the coating film becomes weak, and the recoatability and workability are reduced.

Here, the α, β-unsaturated carboxylic acid includes unsaturated monobasic acids such as acrylic acid and methacrylic acid;
And unsaturated dibasic acids such as itaconic acid and maleic acid.

In the present invention, the non-crosslinkable monomer mixture
It is preferable that (A) and (B) contain (meth) acrylate monomers in a range of 40 to 60%.
If the amount of the (meth) acrylic ester-based monomer is less than 40%, the removability of the coating film tends to decrease, and if it exceeds 60%, it tends to be difficult to obtain sufficient gloss.

Here, (meth) acrylate monomers such as ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, etc. Acrylate-based monomers, methyl methacrylate, ethyl methacrylate, propyl methacrylate, ethylhexyl methacrylate, n-methacrylic acid
Examples include methacrylate monomers such as butyl and lauryl methacrylate.

In the present invention, the first step and the second step
Non-crosslinkable monomer mixture used in step copolymerization reaction
(A) and (B) must have a composition such that the calculated glass transition temperature (Tg) of the copolymer obtained by copolymerizing each non-crosslinkable monomer mixture is 30 to 80 ° C. Is preferred.

Here, the calculated glass transition temperature (Tg) is a value obtained by multiplying the reciprocal of the glass transition temperature of the homopolymer of each component by the weight fraction of each component, which is obtained by the following formula. It is the reciprocal of the sum.

(Equation 1)

In the above formula, Tg indicates a calculated glass transition temperature of the copolymer, and Tga, Tgb, Tgc and Tgz are (a)
, (B), (c) and (z) indicate the glass transition temperature of the homopolymer of each component, Wa, Wb, Wc and Wz are (a), (b)
, (C) and (z) show the weight fraction of each component.

With a composition having a calculated glass transition temperature of less than 30 ° C., the resulting coating film is too soft, so that shoe marks and the like are apt to be formed.
If the composition is higher than ° C, the resulting coating film is too hard and slippery, and the film-forming property is deteriorated, and the performance such as glossiness is deteriorated.

Non-crosslinkable monomer mixture used in the first stage copolymerization reaction of the emulsion copolymer for floor gloss composition of the present invention
(A) and the non-crosslinkable monomer mixture (B) used in the second-stage copolymerization reaction are the same as the former (100 parts by weight) but the latter (50 to 90 parts by weight).
It is preferably used in an amount of 0 parts by weight, particularly 50 to 200 parts by weight. When the latter ratio is less than 50 parts by weight, the strength of the resulting floor gloss composition coating film is reduced, and when it is more than 900 parts by weight, the weak alkaline property applied in the recoating stage is reduced. The coating film obtained by using the floor gloss composition of (1) tends to swell, and as a result, the surface of the coating film is roughened by the force of a mop or the like, causing a reduction in gloss, which is not preferable.

The emulsion copolymer for floor gloss composition of the present invention comprises:
The non-crosslinkable monomer mixture (A) is emulsion-copolymerized according to the method used for ordinary emulsion copolymerization, and then the non-crosslinkable monomer is mixed in the presence of the obtained emulsion copolymer. It is prepared by emulsion copolymerization of the body mixture (B).

In the present invention, as the emulsifier used in the emulsion copolymerization, an emulsifier usually used in emulsion polymerization, for example, an anion such as sodium lauryl sulfate, sodium dodecylbenzenesulfonate, alkyl allyl polyether sulfate, etc. Emulsifier or polyoxyethylene nonyl phenyl ether, oxyethylene
One or more nonionic emulsifiers such as an oxypropylene copolymer can be appropriately selected and used.

Examples of the polymerization initiator include those commonly used in emulsion copolymerization, that is, radical generators such as persulfates such as ammonium persulfate and potassium persulfate, hydrogen peroxide and the like, and radical generators such as these. And a so-called redox-based catalyst comprising a combination of and tartaric acid.

The emulsion copolymer for floor gloss composition of the present invention thus obtained can be converted into a floor gloss composition by mixing with other components usually used in producing floor gloss compositions. Can be. Here, other components include wax such as polyethylene, film forming aid such as tributoxyethyl phosphate, antifreezing agent such as carbitol, alkali-soluble resin such as styrene-maleic acid resin, and elimination of silicone emulsion and the like. Examples thereof include foaming agents, metal complexes such as zinc ammonium carbonate, and leveling agents mainly containing a fluorine-based surfactant.

[0028]

EFFECT OF THE INVENTION The use of the emulsion copolymer for floor gloss composition of the present invention provides a high gloss, excellent durability, and a floor gloss that achieves both recoatability, workability, and coating film removability. Give the composition.

The reason why the emulsion copolymer for floor gloss composition of the present invention exhibits such excellent performance is that a monomer mixture containing no carboxyl group and a monomer mixture containing a carboxyl group are prepared in two stages. In order to emulsify and copolymerize, the resulting emulsion copolymer particles have a small number of carboxyl groups inside,
It is considered that this is based on the fact that it has a layer structure in which there are many carboxyl groups near the surface layer.

[0030]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, which should not be construed as limiting the invention thereto. In the following, parts mean parts by weight unless otherwise specified.

Example 1 1270 g of ion-exchanged water was placed in a glass reactor equipped with a thermometer, a stirrer, a dropping funnel, a gas inlet tube and a reflux condenser.
Emar 20CM (Kao Corporation anionic surfactant) 1
7.8 g and 5 g of Emulgen 930 (nonionic surfactant manufactured by Kao Corporation) were added, and the system was purged with nitrogen and heated in a hot water bath. After the liquid temperature reaches 65 ℃, 2g of potassium persulfate
And stirred and dissolved, and a monomer mixture of 134 g of styrene, 33.5 g of methyl methacrylate, and 82.5 g of butyl acrylate [calculated glass transition temperature of a copolymer obtained by copolymerizing this monomer mixture (hereinafter, referred to as Simply abbreviated as “copolymer Tg”): 30 ° C.] over 90 minutes to carry out emulsion polymerization.

After completion of the dropwise addition, stirring was continued at 65 ° C. for 20 minutes, and a monomer mixture of 40 g of methacrylic acid, 112.5 g of styrene, 28.3 g of methyl methacrylate and 69.2 g of butyl acrylate (copolymer Tg: 51 ° C.) Was added dropwise over 90 minutes to carry out emulsion copolymerization. After completion of the dropwise addition, the temperature was raised to 75 ° C., and the temperature was further maintained for 120 minutes, and then cooled to room temperature to obtain an emulsion copolymer (1) for a floor gloss composition. The glass transition temperature (Tg) of this emulsion copolymer is 40 ° C., and the obtained emulsion copolymer is
It had a solids content of 31.0%.

Example 2 The same amounts of ion-exchanged water and an emulsifier (Emal 20CM, Emulgen 930) were placed in the same reaction vessel as in Example 1, the system was purged with nitrogen, and then heated in a hot water bath. After the liquid temperature reached 65 ° C., 2 g of potassium persulfate was added and dissolved by stirring, and the following monomer mixture (copolymer Tg: 50 ° C.) was added dropwise over 90 minutes to carry out emulsion copolymerization. 134 g of styrene 59.5 g of methyl methacrylate 56.5 g of butyl acrylate After dropping, stirring was continued at 65 ° C for 20 minutes, and the following monomer mixture (copolymer Tg: 50 ° C) was added dropwise over 90 minutes to obtain emulsion copolymerization. Was done. 40 g of methacrylic acid 112.5 g of styrene 27 g of methyl methacrylate 27 g of butyl acrylate After the completion of the dropwise addition, the temperature was raised to 75 ° C, and the temperature was maintained for 120 minutes, and then cooled to room temperature. )
I got Set glass transition temperature (Tg) of this emulsion copolymer
Was 50 ° C., and the obtained emulsion copolymer had a solid content of 30.9%.

Example 3 The same amounts of ion-exchanged water and an emulsifier (Emal 20CM, Emulgen 930) were placed in the same reaction vessel as in Example 1, the system was purged with nitrogen, and then heated in a hot water bath. After the liquid temperature reached 65 ° C., 2 g of potassium persulfate was added and dissolved by stirring, and the following monomer mixture (copolymer Tg: 30 ° C.) was added dropwise over 108 minutes to carry out emulsion copolymerization. Styrene 160.8 g Methyl methacrylate 40.2 g Butyl acrylate 99 g After completion of the dropwise addition, continue stirring at 65 ° C for 20 minutes, and further add the following monomer mixture (copolymer Tg: 51 ° C) over 72 minutes to perform emulsion copolymerization. Was done. 32 g of methacrylic acid 90 g of styrene 22.4 g of methyl methacrylate 55.6 g of butyl acrylate After the completion of the dropwise addition, the temperature was raised to 75 ° C., the temperature was further maintained for 120 minutes, and then cooled to room temperature. )
I got Set glass transition temperature (Tg) of this emulsion copolymer
Was 38 ° C., and the obtained emulsion copolymer had a solid content of 30.9%.

Comparative Example 1 A monomer mixture (copolymer Tg: 40 ° C.) having a composition equal to the sum of the monomer components used in the first stage polymerization and the second stage polymerization in Example 1 was used. , Polymerized in one step,
A comparative emulsion copolymer (1) was obtained.

Comparative Example 2 The same amounts of ion-exchanged water and an emulsifier (Emal 20CM, Emulgen 930) were placed in the same reaction vessel as in Example 1, the system was purged with nitrogen, and then heated in a hot water bath. After the liquid temperature reached 65 ° C., 2 g of potassium persulfate was added and dissolved by stirring, and the following monomer mixture (copolymer Tg: 36 ° C.) was added dropwise over 144 minutes to carry out emulsion copolymerization. 20 g methacrylic acid 203.7 g styrene 53.7 g methyl methacrylate 50.9 g butyl acrylate 125.4 g And emulsion copolymerization. 20 g of methacrylic acid 42.9 g of styrene 10.7 g of methyl methacrylate 10.7 g of butyl acrylate 26.4 g Was. The set glass transition temperature (Tg) of this emulsion copolymer was 40 ° C., and the obtained emulsion copolymer had a solid content of 31.1%.

Comparative Example 3 The same amounts of ion-exchanged water and an emulsifier (Emal 20CM, Emulgen 930) were placed in the same reaction vessel as in Example 1, the system was purged with nitrogen, and then heated in a hot water bath. After the liquid temperature reached 65 ° C., 2 g of potassium persulfate was added and dissolved by stirring, and the following monomer mixture (copolymer Tg: 30 ° C.) was added dropwise over 144 minutes to carry out emulsion copolymerization. Styrene 214.4 g Methyl methacrylate 53.6 g Butyl acrylate 132 g After completion of dropping, continue stirring at 65 ° C for 20 minutes, and further drop the following monomer mixture (copolymer Tg: 87 ° C) over 36 minutes to obtain emulsion copolymerization. Was done. Methacrylic acid 40 g Styrene 32.1 g Methyl methacrylate 7.9 g Butyl acrylate 20 g After completion of the dropwise addition, the temperature was raised to 75 ° C., and the temperature was maintained for 120 minutes, and then cooled to room temperature to obtain Comparative Emulsion Copolymer (3). . The set glass transition temperature (Tg) of this emulsion copolymer was 40 ° C., and the obtained emulsion copolymer had a solid content of 31.1%.

Example 4 Emulsion copolymers (1) to (3) for floor gloss compositions and comparative emulsion copolymers (1) to (3) obtained in Examples 1 to 3 and Comparative examples 1 to 3, respectively. ) Were used to prepare floor gloss compositions according to the following formulations. Emulsion copolymer (solids) 15 parts SMA2625A (solids) ^{* 1} 1.5 parts zinc ammonium carbonate (zinc content 0.14 parts) 1.5 parts Hytec E-4A (solids) ^{* 2} 2.0 parts ethyl carbitol 5.0 parts tributoxyethyl Phosphate 1.4 parts FC129 ^{* 3} 0.02 parts Ion-exchanged water ^{* 4} variables * 1 Styrene-maleic acid resin manufactured by Alcochemical USA * 2 Polyethylene wax manufactured by Toho Chemical Co. * 3 Fluorosurfactant manufactured by Sumitomo 3M * 4 Solids concentration Needed to make 20%

Each of the floor gloss compositions thus prepared was applied to a commercially available vinyl-based non-asbestos tile, and comparative tests of various properties of the obtained coating film were performed. The results are shown in Table 1. The test method is as follows.

(Test Method) Gloss: The floor gloss composition was applied to tiles three times at a rate of about 12 ml / m ² , dried at room temperature, and measured for 60 ° specular reflection gloss with a gloss meter.

2. Recoatability: about 12 ml / m ^{2 of} gloss composition
After drying at room temperature, immediately write the letter “X” on the surface of the coating film coated with the glossy composition. After drying at room temperature, how much the letter “X” disappears visually Was evaluated. Excellent: The letter "X" is hardly recognized, or the letter "X" is recognized, but there is almost no protrusion. Impossible; the letter "X" was recognized and there was a bump.

3. Coating film removal property: After applying the glossy composition to the tile (two times of application), drying at room temperature, it is left in a constant temperature room at 40 ° C. for 7 days. The obtained test piece was immersed in a 15-fold diluted solution of a commercially available alkaline release agent for 2 minutes, and then tested using a washability tester. After the test, the degree of removal of the coating film was evaluated. Excellent; coating film completely removed Impossible; coating film remaining

4. Detergent resistance: The glossy composition was applied to the tile (twice) and left at room temperature for one day. The obtained test piece was washed with a detergent solution using a washability tester, and the state of the coating film was evaluated. Excellent; no decrease in gloss and no damage to coating film. Not possible; decrease in gloss and damage to coating film are observed.

[Table 1]

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification symbol FI // C09G 1/16 C09G 1/16 (58) Field surveyed (Int. Cl. ⁶ , DB name) C08F 257/00 C08F 2 / 44 C08F 212/00 C09D 125/00 C09D 151/00 C08L 51/00

Claims (5)

(57) [Claims] In a first step, a non-crosslinkable monomer mixture (A) containing no α, β-unsaturated carboxylic acid and containing 40 to 60% by weight of an aromatic vinyl compound is emulsion-copolymerized. To obtain, in the second stage, a non-aqueous solution containing 10 to 30% by weight of an α, β-unsaturated carboxylic acid and 40 to 60% by weight of an aromatic vinyl compound in the presence of the emulsion copolymer. An emulsion copolymer for floor gloss composition obtained by emulsion copolymerizing the crosslinkable monomer mixture (B). 2. The calculated glass transition of a copolymer obtained by copolymerizing a non-crosslinkable monomer mixture (A) and a copolymer obtained by copolymerizing a non-crosslinkable monomer mixture (B). The emulsion copolymer for floor gloss composition according to claim 1, wherein the temperature (Tg) is 30 to 80 ° C. 3. In the first stage, the composition does not contain α, β-unsaturated carboxylic acid, but contains 40 to 60% by weight of an aromatic vinyl compound and 40 to 60% by weight of a (meth) acrylate monomer. The non-crosslinkable monomer mixture (A ') is emulsion-copolymerized to obtain an emulsion copolymer. In the second step, in the presence of the emulsion copolymer, an α, β-unsaturated carboxylic acid 30% by weight,
Floor gloss obtained by emulsion copolymerization of a non-crosslinkable monomer mixture (B ') containing 40 to 60% by weight of an aromatic vinyl compound and 40 to 60% by weight of a (meth) acrylate monomer. Emulsion copolymer for composition. 4. Calculation of a copolymer obtained by copolymerizing a non-crosslinkable monomer mixture (A ′) and a copolymer obtained by copolymerizing a non-crosslinkable monomer mixture (B ′). Glass transition temperature (T
The emulsion copolymer for floor gloss composition according to claim 3, wherein g) is 30 to 80 ° C. 5. A floor gloss composition comprising the emulsion copolymer for floor gloss composition according to claim 1.