JPH058048B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention is a powder emulsion containing a fungicide, a cement admixture, etc., into microcapsules that have been surface-modified by a powder mixing method using an automatic mixer, stirrer, or other powder mixer. Concerning powder emulsions. (Prior Art) Synthetic resin emulsions are freeze-pulverized or spray-dried into a powder form, commonly known as powder emulsions, which are widely used in paints, adhesives, instant cements, and wet finishing materials. Compared to liquid synthetic resin emulsions, powdered emulsions are useful for improving the ease of application for the aforementioned paints, adhesives, instant cement, wet finishing materials, etc., and they are also useful for manufacturers. This is useful for product manufacturing processability, transportation benefits, and product stability. However, powder emulsions are more difficult to disperse than liquid emulsions when pigments, fungicides, and cement admixtures are mixed, and, for example, color irregularities often occur in pigment dispersions. Also, cement admixtures may cause variations in solidification of cement, which may adversely affect physical properties such as strength. Also, when it comes to antifungal agents, it is important to ensure that they are uniformly dispersed on the surface of the paint.
Similar to pigments, this is difficult, and the effects of antifungal agents are often not fully demonstrated. (Objective of the Invention) The object of the present invention is to solve the above problems by microencapsulating a pigment, a fungicide, and a cement admixture in a powder emulsion. (Structure of the Invention) The present invention integrates pigments, fungicides, cement admixtures, etc. with a powder emulsion using microencapsulation techniques, and forms a thin film continuously or discontinuously on the surface of the powder emulsion. As a result, each molecule becomes extremely stable due to electrical or chemical bonding at the interface between the two. When the powder emulsion is dispersed into the medium,
The powder emulsion is re-emulsified with these pigments, fungicides, or cement admixtures at the interface. This results in stable properties that are completely different from the conventional dispersed case. Microcapsules are widely used in medicines, agricultural chemicals, fragrances, and the like. Especially when applied to pressure-sensitive paper,
It is highly rated. Microencapsulation methods include interfacial polymerization method,
It is classified into in situ method, coacervation method, submerged drying method, orifice method, melt dispersion cooling method, air suspension method, spray drying method, inorganic wall capsule method, etc. The microencapsulation method used in the present invention is classified as an inorganic wall encapsulation method. This mechanochemical surface modification method is often used as an encapsulation technique with powder. The mechanochemical technique of the present invention utilizes frictional heat and electrification caused by mixing, and uses a powdered vinyl synthetic resin emulsion as a core material to coat the surface with pigments, fungicides, cement admixtures, etc. urge Naturally, during mixing, thermal energy is generated due to external pressure, which causes charging or melting of the interface, resulting in a stable bond between the two. Moreover, since this bond is not based on a chemical reaction, the properties of both will not be lost. The details of the invention will be described based on examples. (Example 1) Vinyl synthetic resin powder emulsion [Movinyl DM200: particle size 20 μm to 150 μm, Hoechst Synthetic Co., Ltd.
A microencapsulated powder emulsion was prepared by adding 5 parts by weight of the antifungal agent Coatside N (manufactured by Takeda Pharmaceutical Co., Ltd.) to 100 parts by weight (manufactured by Takeda Pharmaceutical Co., Ltd.). Next, a water-based white paint was prepared according to the recipe shown below. Microencapsulated powder emulsion
105 (parts by weight) Calcium carbonate 400 Titanium oxide 100 Methyl cellulose 4 Water 300 Ethylene glycol 10 Texanol 10 Next, a test was conducted according to JIS Z 2911 to observe the growth of mold. (However, in order to promote the growth of mold and to check for elution and exudation, wash the surface with sterile water once every week, and use 50% as a bacterial strain solution.
% dextrose solution was added again. ) As shown in Table 1, the growth of mold could be delayed. (Example 2) 50 parts by weight of montanic acid ester wax was added to 100 parts by weight of the fungicidal microencapsulated powder emulsion prepared in Example 1 and mixed with an automatic mixer to obtain the primary microencapsulated powder. Secondary microencapsulation was performed on the surface of the emulsion. Regarding the growth of mold, observation was carried out using the method of Example 1, and it was found that the growth of mold could be significantly delayed. The results are shown in Table 2. (Example 3) Using the same mixer as in Example 1, for 100 parts by weight of the powder emulsion used in Example 1,
A microencapsulated powder emulsion was prepared by adding 2 parts by weight of methyl cellulose as an admixture for cement. Next, the microencapsulated powder
10.2 parts by weight and 100 parts by weight of white Portland cement were added, 40 parts by weight of water was added, and the adhesion strength specified in JIS A6916 was measured. The result was 20Kg/cm ² under standard conditions. (Reference example 1) Vinyl synthetic resin powder emulsion [Movinyl DM200: particle size 20 μm to 150 μm, Hoechst Synthetic Co., Ltd.
50 parts by weight of ferric oxide as a colored pigment and a pigment (particle size 0.1 to 0.8 μm) were mixed for 5 hours with an automatic mixer. Immediately after mixing, the powder temperature rose by about 5°C from 20°C before mixing, and the state of the powder was visually uniform. Next, add 15 parts by weight of this microencapsulated powder and 100 parts by weight of white Portland cement, add 40 parts by weight of water, and mix using a mixing tip and spoon specified in JIS R5201. Length 100mm x width 100
A rectangular parallelepiped of mm in size was molded and cured indoors for 7 days to prepare a test specimen. After curing, the color development and surface density were observed, and the specimen was further tested for 4
When exposed outdoors for a week and observed for its surface color tone, it was found to be very excellent in terms of color development, surface density, and color tone after exposure. The results are shown in Table 3. (Comparative Example 1) The same ingredients as the test specimen molded in Reference Example 1, namely, white Portland cement 100 (parts by weight) vinyl powder emulsion 10 ferric oxide pigment 5 water 40 were prepared in the same manner as in Reference Example 1. After molding and curing, color development, surface density, and color tone after exposure were evaluated. The results are shown in Table 3. (Comparative Example 2) Among the water-based paint formulations shown in Example 1, microencapsulated powder emulsion (Movinyl
A water-based paint was prepared by changing 100 parts by weight of DM200) and 5 parts by weight of the antifungal agent (Courtside N), and evaluated by the method shown in Example 1 and the method shown in Example 2.
The results are shown in Tables 1 and 2. (Comparative Example 3) A test specimen was prepared in the same manner as in Example 3 using the same ingredients as the mortar prepared in Example 3, namely, white Portland cement 100 (parts by weight), vinyl powder emulsion 10, methyl cellulose 0.2 and water 40. The test was evaluated in a similar manner. The result was 13Kg/cm ² under standard conditions. In the symbols indicating the evaluation of Examples and Comparative Examples, regarding color development, the more + symbols there are, the better the color development is. Furthermore, regarding the evaluation symbols indicating mold resistance in Tables 1 and 2, - means no mold growth is observed. ± is a state in which it is difficult to distinguish whether mold growth is observed or not. + sign is 1
In some cases, slight mold growth is observed,
The larger the number, the more mold has grown.

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[Table] "Effects of the Invention" In the present invention, as can be understood from the above Examples and Comparative Examples, various effects can be obtained depending on the type of microencapsulated emulsion. For example, when a pigment is used for microencapsulation as in Reference Example 1, a product with stable color development and excellent weather resistance can be obtained. In addition, when the antifungal agent is microencapsulated and used as in Example 1, a stable effect can be obtained over a long period of time compared to when a conventional antifungal agent is directly added to the paint. Furthermore, if secondary processing is performed for microencapsulation as in Example 2, the effect can be further extended even with respect to the results for the antifungal agent alone. When used as a cement admixture as in Example 3, stable cohesive force can be obtained. In this way, the synergistic effect of the microencapsulated emulsion, pigment, and antifungal agent has the effect of consistently exhibiting the characteristics of each substance both initially and over a long period of time.

Claims (1)

[Claims] 1. Powdered fungicide or cement admixture powder is continuously or discontinuously applied to the surface of the powder emulsion at room temperature by a powder mixing method. A microencapsulated powder emulsion characterized by forming a thin film to perform microencapsulation. 2 Form a powdery thin film continuously or discontinuously on the surface of the powder emulsion by mixing powdered fungicide or cement admixture and pigment powder at room temperature on the surface of the powdered emulsion. A microencapsulated powder emulsion characterized by microencapsulation.