JPS621980B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to aqueous dispersions for floor gloss compositions. In detail, it is used to polish and protect rubber tiles, vinyl tiles, vinyl asbestos tiles, linoleum tiles, etc.
This invention relates to an aqueous dispersion for floor gloss compositions with excellent film-forming properties and adhesion. Floor gloss compositions have detergent resistance, which means that the film that is obtained when applied to the floor and dries, retains a good gloss even with normal care with water or detergent, and also has the property of being resistant to detergents, which means that it retains a good gloss when it is applied to a floor and dries. removability is required so that it can be easily removed. In other words, it is required to achieve both the contradictory properties of detergent resistance and removability. In order to achieve this requirement, methods have been proposed in which emulsion copolymers are used in combination with polyvalent metal ions or polyvalent metal complex salts.
It is disclosed in the specifications of No. 19570 or No. 53-37314. Although these methods are effective in achieving both detergent resistance and removability, they still pose new problems as shown below. That is,
In floor gloss compositions containing polyvalent metal ions or polyvalent metal complex salts, the fusion of the emulsion copolymer particles with each other is hindered, resulting in a decrease in film-forming properties, especially when applied to floor surfaces at low temperatures. A so-called whitening phenomenon in which a continuous film is not formed tends to occur, and in order to prevent this, it is necessary to add a large amount of film-forming aid. In addition, floor gloss compositions that contain polyvalent metal ions or polyvalent metal complexes have poor adhesion to the surface of floor substrates, especially those with dense surfaces such as vinyl tiles, vinyl sheets, or rubber tiles, which have been increasing in recent years. It hardly adheres to flooring materials with
It tends to peel off from the flooring material due to the impact it receives when walking, causing a powdering phenomenon. Furthermore, in order to stably coexist the emulsion copolymer with polyvalent metal ions or polyvalent metal complexes, it is necessary to adjust the pH to a high level with ammonia or amine, which results in ammonia and amine odors occurring during the coating process. It degrades the working environment. In addition to these issues,
Polyvalent metal ions will be contained in the waste liquid when the coating is removed. Currently, the most commonly used metal ion for polyvalent metal ions or polyvalent metal complexes is zinc ion, which is a substance subject to emission control under the Water Pollution Control Law.
There is a risk of contaminating the living environment. As described above, there are several problems with the method of using polyvalent metal ions or polyvalent metal complexes in combination. On the other hand, the use of polymers produced by solution polymerization in floor gloss compositions is disclosed in Japanese Patent Publication No. 14019/1983, but the polymers in this book contain relatively many carboxyl groups and have low molecular weight. Therefore, although the removability is excellent, the detergent resistance is not necessarily satisfactory. Furthermore, the use of so-called oligomer-like polymers containing a larger amount of carboxyl groups and having a smaller molecular weight is disclosed in JP-A-52-124487 and British Patent No. 1515943; Floor gloss composition coatings using oligomer-like polymers are self-dispersing and dissolve the previous coating during reapplication of the floor gloss composition, achieving removal and polishing in one operation. Since this is also the objective, removability is of course very easy, but detergent resistance cannot be said to be sufficient. In view of the current situation, the inventors of the present invention have conducted repeated research to solve various problems with conventional floor gloss compositions. An aqueous dispersion obtained by adjusting the molecular weight to a specific range by replacing the alcohol solvent with water, and in which the average particle diameter of the dispersed particles is a specific value or less, has excellent performance as a floor gloss composition. The present inventors have discovered that the present invention can solve various problems of conventional floor gloss compositions, and have completed the present invention. Therefore, the object of the present invention is to provide a floor gloss composition that has excellent performance as a floor gloss composition, particularly has excellent low-temperature film formability and adhesion, and has a good balance between removability and detergent resistance. The present invention provides an aqueous dispersion that provides the following properties. The aqueous dispersion for floor gloss composition of the present invention has α, β
- Unsaturated carboxylic acid (A), acrylic acid alkyl ester having an alkyl group having 2 to 8 carbon atoms (B), methyl methacrylate (C), and others that can be copolymerized with components (A) to (C). It consists of α, β-unsaturated monomer (D) of
And the proportion of each component is (A):(B):(C):(D)=5 by weight
~8:20~40:50~75:0~10 (However, (A)
(D) A monomer mixture () having a proportion in the range of 100% by weight) is polymerized in a lower alcohol having 1 to 3 carbon atoms to form a copolymer () with a molecular weight of 30,000 to 70,000. The average particle diameter of the dispersed particles is is 0.1
It is characterized by being smaller than microns. The copolymer () of the aqueous dispersion for a floor gloss composition of the present invention comprises an α,β-unsaturated carboxylic acid (A), an acrylic acid alkyl ester having an alkyl group having 2 to 8 carbon atoms (B), Methyl methacrylate (C) and other α, β copolymerizable with components (A) to (C) if necessary
The α,β-unsaturated carboxylic acid (A) used in the present invention is obtained by polymerizing a monomer mixture () containing the unsaturated monomer (D) as a component. A)
It is used in an amount of 5 to 8% by weight based on the total amount of components (D). When the amount of α,β-unsaturated carboxylic acid (A) is less than 5% by weight, the dispersed particle size
It becomes difficult to obtain an aqueous dispersion with a size of 0.1 micron or less. Conversely, if it exceeds 8% by weight, the water resistance of the coating of the floor gloss composition using the resulting aqueous dispersion will be insufficient. Examples of the α,β-unsaturated carboxylic acid (A) include acrylic acid, methacrylic acid, and itaconic acid. Examples of the acrylic acid alkyl ester (B) having an alkyl group having 2 to 8 carbon atoms include ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc. One or two of these The above can be used. The amount used is in the range of 20 to 40% by weight based on the total amount of components (A) to (D). If the amount used is less than 20% by weight, the film forming temperature of the resulting aqueous dispersion will be high and a large amount of film forming aid will be required when applied to a floor gloss composition. On the other hand, if the amount exceeds 40% by weight, the coating formed in the floor gloss composition will be soft and the black heel mark resistance will be poor. Methyl acrylate, which has a methyl group which is an alkyl group with one carbon number as the alkyl group of the acrylic acid alkyl ester, has too high hydrophilicity and the gloss and water resistance of the obtained film are insufficient. Acrylic acid alkyl esters having nine or more alkyl groups are too hydrophobic and sticky, making it difficult to obtain an aqueous dispersion with balanced performance. Methyl methacrylate (C) used in the present invention is
It is used in a proportion ranging from 50 to 75% by weight based on the total amount of components (A) to (D). If the amount used is less than 50% by weight, the viscosity of the resulting aqueous dispersion may increase or the coating formed into a floor gloss composition may become soft. On the other hand, if the amount exceeds 75% by weight, the film will become hard but the film formability will decrease. Other α,β-unsaturated monomers (D) that can be copolymerized with components (A) to (C) include aromatic vinyl monomers such as styrene and α-methylstyrene; acrylonitrile and methacrylonitrile. unsaturated nitriles such as; or vinyl esters such as vinyl acetate and vinyl propionate. These α,β-unsaturated monomers (D) are appropriately selected depending on the desired physical properties of the aqueous dispersion, and are 0 to 10% of the total amount of components (A) to (D). Used in proportions ranging from 10% by weight. The aqueous dispersion for floor gloss compositions of the present invention is obtained by polymerizing the monomer mixture () having such a composition in a lower alcohol having 1 to 3 carbon atoms, and having a molecular weight of 30,000 to 30,000.
After making a copolymer () within the range of 70,000, by adding a base in an amount equivalent to 50 to 100% of the carboxyl groups in the copolymer () and replacing the lower alcohol with water. The average particle diameter of the dispersed particles is 0.1 micron or less. Examples of the lower alcohol having 1 to 3 carbon atoms include methyl alcohol, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol, and one or more of these can be used. Among these, especially methyl alcohol,
Isopropyl alcohol or a mixture thereof is preferably used. The solution polymerization method disclosed in the above-mentioned Japanese Patent Publication No. 47-14019 uses a high boiling point solvent that can be mixed with water for the purpose of lowering the molecular weight, and since it is not distilled off after polymerization, the amount of solvent used is less than that of the emulsified dispersion. Limited to a small amount that can remain inside. However, in the present invention, since a lower alcohol having a boiling point lower than that of water is used and substantially all of the alcohol is distilled off when replacing water to form an aqueous dispersion, there is no restriction on the amount of the lower alcohol used as a solvent, and it can be used as desired. It can be polymerized at a monomer concentration of As the polymerization initiator, a polymerization initiator commonly used in solution polymerization can be used. For example, organic peroxides such as benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide, or 2,
2'-azobisisobutyronitrile, 1,1'-azobiscyclohexane-1-carbonitrile, 2,
Azo catalysts such as 2'-azobis-2,4-dimethylvaleronitrile are used. The molecular weight of the copolymer () in the present invention is
It must be within the range of 30,000 to 70,000 (measured by GPC method using polystyrene of known molecular weight as a standard material). Molecular weight of copolymer ()
A molecular weight regulator may be used to maintain the molecular weight within the range of 30,000 to 70,000, but it can also be achieved by appropriately selecting the monomer concentration and initiator concentration without using a molecular weight regulator. It is. If the molecular weight of the copolymer () is less than 30,000, the detergent resistance of the film will be insufficient when used as a floor gloss composition;
If the molecular weight exceeds 0.1 micron, it becomes difficult to obtain an aqueous dispersion in which the dispersed particles have an average particle diameter of 0.1 micron or less and have a practical concentration. After solution polymerization, before or after distilling off the lower alcohol as a solvent, the copolymer ()
A base and water in an amount equivalent to 50 to 100% of the carboxyl groups in the alcohol are added to form a lower alcohol-water mixed dispersion, and substantially all of the lower alcohol is distilled off to form an aqueous solution. Make it a dispersion.
Ammonia or a volatile amine is used as the base to be added, and one or more bases selected from the group consisting of ammonia, trimethylamine, and triethylamine are particularly preferred. On this occasion,
If the amount of base added is less than the amount equivalent to 50% of the carboxyl groups in the copolymer (), the copolymer () will not be sufficiently dispersed, and the average particle diameter of the dispersed particles will tend to increase. If the average particle diameter of the dispersed particles of the aqueous dispersion is larger than 0.1 micron, the gloss of the coating will not be sufficient when used as a floor gloss composition, which is not preferable. The aqueous dispersion thus obtained according to the invention is mixed with the other ingredients normally used in producing floor gloss compositions. Other commonly used ingredients include waxes such as paraffin, montan, and polyethylene wax; plasticizers such as dibutyl phthalate and tributoxyethyl phosphate; diethylene glycol monoethyl ether,
Examples include film-forming aids such as butyl cellosolve; alkali-soluble resins such as rosin-modified maleic acid resins and styrene-maleic acid resins; and leveling agents mainly containing fluorine-based surfactants. The thus obtained floor gloss composition using the aqueous dispersion of the present invention exhibits good low-temperature film formability and adhesion, and also has good detergent resistance and removability without using polyvalent metal ions. It has excellent performance that was unimaginable with conventional emulsion copolymers, achieving a high level of performance balance with The reason why the aqueous dispersion according to the present invention exhibits such excellent performance is that the aqueous dispersion obtained according to the present invention has a higher concentration in the copolymer () than a polymer obtained by a conventional emulsion polymerization method. Because the distribution of carboxyl groups is uniform and the molecular weight is low, dispersed particles with a small particle size can be obtained even with a relatively small content of carboxyl groups, and it does not contain any emulsifier. More specifically, in emulsion copolymers that do not contain polyvalent metal ions, the fusion of dispersed particles progresses over time and the polymer chains become entangled, so removability decreases if the film is left for a long time. As mentioned above, the aqueous dispersion of the present invention always exhibits good removability because the distribution of carboxyl groups in the copolymer () is uniform and the molecular weight is low. Furthermore, since no emulsifier is used, it has excellent water resistance. Therefore, it is possible to achieve both detergent resistance and removability, which have conventionally been problematic when polyvalent metal ions are not used. Furthermore, the aqueous dispersion of the present invention has a high plasticizing efficiency with a plasticizer and has the property of forming a film effectively even with a small amount of plasticizer, so it has better low-temperature formation than floor gloss compositions using polyvalent metal ions. It has membrane properties. In addition, since the molecular weight is lower than that of copolymers obtained by ordinary emulsion polymerization, it has good adhesion to substrates, and there is no powdering phenomenon seen with types that use polyvalent metal ions, making it highly durable. It is also excellent. Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. However, it goes without saying that the present invention is not limited to these examples. In addition, unless otherwise specified, "part" in the examples means parts by weight, and "%" means weight %. In addition, the viscosity of the aqueous dispersion was measured at 25°C using a Bismetron viscometer (manufactured by Seiki Kogyo Research Institute), and the average particle diameter of the dispersed particles was measured by an electron microscope (“Super Scope JEM-50B” manufactured by JEOL). death,
The molecular weight of the copolymer () was measured using a high-performance liquid chromatograph
Example 1 The monomer mixture, solvent components and initiator shown in Table 1 were placed in a glass reaction vessel equipped with a thermometer, stirrer, dropping funnel, gas inlet tube and reflux condenser. After adding 80 parts of the reaction mixture consisting of the components, the system was purged with nitrogen and then heated in a hot water bath. After starting reflux at 81°C, the reaction was continued for 30 minutes, and then the remaining 322.4 parts of the reaction mixture was added to 2 parts at the same temperature. After dropping, the reaction solution was brought to the reflux temperature for 3 hours.
It kept time. After the polymerization reaction is completed, ammonia and water in the amounts shown in Table 1 are added to form an alcohol-water mixed dispersion, and then heated again to dissolve the total amount of isopropyl alcohol used as a solvent and a portion of the water.
259 parts were distilled off to obtain a 40% aqueous dispersion (). This aqueous dispersion () had a viscosity of 31 centipoise and a pH of 7.5, the average particle diameter of the dispersed particles was 0.07 microns, and the molecular weight of the copolymer was 56,000. Example 2 Aqueous dispersion 2 was obtained in the same manner as in Example 1, except that the monomer mixture components shown in Table 1 were used, and ammonia and triethylamine were used in combination as bases added during dispersion. This aqueous dispersion 2
The concentration, viscosity and pH of the copolymer, the average particle diameter of the dispersed particles, and the molecular weight of the copolymer were as shown in Table 1. Example 3 Aqueous dispersion 3 was obtained in the same manner as in Example 1, except that the monomer mixture component, solvent component, and initiator component shown in Table 1 were used. The concentration, viscosity and pH of this aqueous dispersion 3, the average particle diameter of the dispersed particles, and the molecular weight of the copolymer were as shown in Table 1. Comparative Examples 1 to 4 Comparative dispersions 1 to 4 were obtained in the same manner as in Example 1 using the monomer mixtures, solvent components, and initiator components shown in Table 1, respectively. The concentration, viscosity and pH of these comparative dispersions, the average particle diameter of the dispersed particles, and the molecular weight of the copolymer were as shown in Table 1. Comparative Example 5 In a reaction vessel similar to that used in Example 1, water was added.
290 parts and 8 parts of "Neoperex F-60" (anionic surfactant, manufactured by Kao Atlas Co., Ltd.) were added, and after purging the system with nitrogen, it was heated in a hot water bath. Liquid temperature is 60
After reaching ℃, the monomer mixture shown in Table 1, water
An aqueous initiator solution consisting of 37 parts and 4.7 parts of 35% hydrogen peroxide and an aqueous reducing agent solution consisting of 40 parts of water and 8.6 parts of ascorbic acid were each added dropwise over a period of 2 hours. After completion of the dropwise addition, the temperature was further raised to 80°C, maintained at the same temperature for 1 hour, and then cooled to room temperature to obtain Comparative Dispersion 5. The concentration, viscosity and pH of this comparative dispersion 5, the average particle diameter of the dispersed particles, and the molecular weight of the copolymer were as shown in Table 1.

【table】

[Table] Example 4 Using the aqueous dispersions, comparative dispersions, or commercially available metal salt-added emulsified dispersions obtained in Examples 1 to 3 and Comparative Examples 1 to 5, floor gloss compositions were prepared according to the following formulations. Prepared. Dispersion (adjusted to 25% solid content) 75 parts “Duretsu 19788” (Note 4) (〃) 10 parts “Polyem” (Note 5) (〃) 15 parts Ethicarbitol 4.5 parts Tributoxyethyl phosphate 0.6 Part “FC-128” (Note 6) (adjusted to 1% solid content)
0.5 parts Water (Note 7) Variable (Note 4) Alkali-soluble resin, manufactured by Sumitomo Duretz (Note 5) Polyethylene wax, manufactured by Costen Oil (Note 6) Fluorine surfactant, manufactured by Sumitomo 3M Limited (Note 7) Amount required to achieve a solid content concentration of 20% The storage stability of each of the floor gloss compositions prepared in this manner and various performances when applied to commercially available vinyl asbestos tiles were compared. The results are shown in Table 2. The performance test method is as follows. Test method 1 Storage stability: Judging from viscosity change and presence or absence of phase separation after storage in a constant temperature bath at 50°C for 20 days. 2 Recoatability: Evaluate the surface condition when recoating is performed at 30 minute intervals. 3 Gloss: Apply two coats of floor gloss composition, 20
The 60° specular reflection gloss was measured after being left for 24 hours at ℃ and 65% RH using a gloss meter (“GM-3M” manufactured by Murakami Color Giken). 4 Adhesion: The peeling state of the coating film was determined by cross-cutting the surface coated with the floor gloss composition at 1 mm intervals, applying cellophane tape (manufactured by Nichiban) on top of it, and peeling it off at a 90° angle. evaluate. 5. Removability: Judge the peeling condition after 20 minutes of immersion in the standard stripping solution specified by the Japan Floor Polish Industry Association. 6 Water resistance: Determined using the method specified by the Japan Floor Polish Industry Association. 7 Black heel mark resistance; The white vinyl asbestos tile surface coated with a floor gloss composition was rotated at a rotation speed of 600 rpm (rotating radius of 7
Judging from the dirt and scratches caused when struck with cm).

[Table] Performance comparison shows that performance gradually decreases in the order of excellent, good, and fair. (Excellent...Excellent, Good...Good, Fair...Practical).

Claims (1)

[Scope of Claims] 1 α,β-unsaturated carboxylic acid (A), carbon number 2 to 8
Acrylic acid alkyl ester (B) having 1 alkyl group, methyl methacrylate (C), and (A) to (C)
Other α,β-unsaturated monomers (D) copolymerizable with the component
and the ratio of each component is (A):(B):
(C):(D)=5-8:20-40:50-75:0-10 (However, the total ratio of components (A) to (D) is 100% by weight)
A monomer mixture () having a proportion in the range of is polymerized in a lower alcohol having 1 to 3 carbon atoms, and the molecular weight is
After making a copolymer () of 30,000 to 70,000, by adding a base in an amount equivalent to 50 to 100% of the carboxyl groups in the copolymer () and replacing the lower alcohol with water. An aqueous dispersion for a floor gloss composition obtained, characterized in that the average particle diameter of the dispersed particles is 0.1 micron or less. 2. The aqueous dispersion for a floor gloss composition according to claim 1, wherein the lower alcohol having 1 to 3 carbon atoms is one or two selected from the group consisting of methyl alcohol and isopropyl alcohol. 3. The aqueous dispersion for a floor gloss composition according to claim 1, wherein the base is one or more selected from the group consisting of ammonia, trimethylamine, and triethylamine.