JP2008095031A - Heat insulating coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating material containing hollow beads which contains a high proportion of the hollow beads and, at the same time, can maintain the functions as a coating material (such as adequate viscosity, elasticity and adhesive strength). <P>SOLUTION: The heat insulating coating material comprises hollow beads, an acrylic resin emulsion and function retaining agents. The hollow beads occupy 45-50 vol% of the whole volume, and as the function retaining agents a high boiling point oil, a viscosity regulator, an auxiliary for film-forming and an antifoaming agent are contained. After the coating and drying the hollow beads occupy 55-70 vol% of the whole volume. The hollow beads are vacuum hollow beads made of an acrylonitrile resin. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a composition for coating other equipment such as a roof of a building, an outer wall surface, an inner wall surface, etc., and particularly a coating material having heat insulating properties, waterproof properties and sound insulating properties for forming a heat insulating layer. About.

  Conventionally, as a heat insulating material for blocking heat conduction between the outside and the inside of a building, foamed polystyrene, glass wool, etc. were generally used, but there are many difficulties in workability, environment and economy, etc. I was in a hurry. As one of the countermeasures, development of a coating material that forms a heat-insulating coating film is underway. The coating film formed by the heat insulating coating material can exhibit the same level of heat insulating property as a thin film compared to conventional heat insulating materials, enhance the cooling / heating effect, and contribute to energy saving.

  As a coating material for forming a heat-insulating coating film, a mixture of inorganic or organic hollow fine particles (also referred to as hollow beads, bubbles or balloons) with an average particle size of several tens of μm in a resin emulsion paint, etc. It has been known. In the coating film formed with such a coating material, a heat insulating effect is obtained by the air layer of the hollow fine particles uniformly dispersed in the coating film. Examples of inorganic hollow fine particles include shirasu, silica, ceramic, and glass, and examples of organic hollow fine particles include vinylidene chloride resin and acrylonitrile resin. Further, it is known that ceramic hollow fine particles and ceramic vacuum hollow fine particles are suitable as hollow fine particles having compressive strength that is not destroyed in the production process and the coating process (Patent Documents 1 to 3).

  Patent Document 1 discloses a heat insulating coating material in which ceramic hollow fine particles having a predetermined compressive strength and bulk specific gravity and an inorganic powder are blended with a synthetic resin emulsion composition that forms a transparent or translucent film layer after drying and curing. ing.

  Patent Document 2 discloses a heat-shielding coating material containing a structure-retaining agent that densely arranges bubbles such as ceramics after forming a coating film.

Patent Document 3 discloses a heat-shielding coating material that contains a pigment having a deep color and reflectivity and hollow fine particles such as a shirasu balloon, a polystyrene balloon, and a ceramic balloon, and has excellent reflection characteristics in the near-infrared wavelength region. Has been.
JP-A-8-127736 JP 11-323197 A JP 2000-129172 A

  A coating material containing hollow fine particles (hereinafter referred to as “hollow beads”) should have a higher heat insulating effect as the content of the hollow beads is higher. However, there is a problem that the viscosity of the coating material as a whole decreases due to a relatively small amount of other components as a binding material relative to the high content of hollow beads, and the elasticity and adhesion as a coating material decrease. It was difficult to increase the content of hollow beads. For example, when used as a coating material for an exterior, it is necessary to form a coating film having a predetermined hardness and impact resistance. Conventionally, the content of hollow beads capable of maintaining the function as a coating material was up to about 20 to 40% by volume.

  The object of the present invention is to provide a heat-insulating coating material containing hollow beads, which contains a high proportion of hollow beads as compared with conventional ones, and at the same time can maintain the function (appropriate viscosity, elasticity, adhesion, etc.) as a coating material. It is to be.

In order to achieve the above object, the present invention provides the following configurations.
(1) The invention according to claim 1 is a heat insulating coating material comprising hollow beads, an acrylic resin emulsion, and a function-retaining agent, wherein the hollow beads are 45 to 50% by volume of the total volume, And it is a heat insulating coating material containing a high boiling point oil, a viscosity modifier, a film-forming auxiliary agent, and an antifoaming agent as the function retaining agent.

(2) The invention according to claim 2 is characterized in that, in the heat insulating coating material of claim 1, the hollow beads are 55 to 70% by volume of the total capacity after the coating and drying of the heat insulating coating material. .

(3) The invention according to claim 3 is characterized in that, in the heat insulating coating material according to claim 1 or 2, the hollow beads are vacuum hollow beads made of acrylonitrile resin.

  The heat-insulating coating material according to the present invention contains hollow beads, an acrylic resin emulsion, and a function-retaining agent, and the hollow beads are 45 to 50% by volume of the total volume in the coating material before coating, which is higher than the conventional one. Amount. Further, the hollow bead content in this coating material corresponds to 55 to 70% by volume of the total volume after coating and drying. As a result, the heat insulating effect and the sound insulating effect of the coating film can be remarkably enhanced by the heat insulating property and sound insulating property of the hollow beads. Further, since the content of hollow beads having a small specific gravity is high, the specific gravity of the coating material itself is also reduced, and the weight can be reduced. Since the heat insulating property is high, the coating film is hardly affected by heat and the deterioration is slow. As a result, the coating film can maintain the waterproof property for a long time and has excellent weather resistance.

  In addition, the heat-insulating coating material according to the present invention includes at least a high-boiling oil, a viscosity modifier, a film forming aid, and an antifoaming agent as a function-preserving agent, so that the coating is performed despite the high content of hollow beads. Appropriate viscosity, elasticity, adhesion, etc. as a material can be maintained. For example, the miscibility between the hollow beads and other components in the production process is improved, and the hollow beads are uniformly dispersed throughout the coating material. Further, in the coating process, the paintability, that is, the workability is improved, and desired mechanical characteristics, thermal characteristics, and good weather resistance can be realized in the formed coating film.

  Furthermore, by using hollow beads made of acrylonitrile resin, the coating material can be made lighter than ceramic hollow beads. Moreover, acrylonitrile resin is preferable at the point which is excellent in heat resistance compared with other resin. In particular, by using vacuum hollow beads (here, “vacuum” includes all states lower than normal pressure), the heat blocking effect is greater than that of air-filled ones. Therefore, it is possible to block the outdoor heat from entering the indoors in the summer and to block the indoor warm air outflow in the winter. Further, the vacuum hollow beads can exhibit high sound insulation properties because sound waves are absorbed in the hollow portions, and have sound insulation and soundproofing effects.

  As described above, the heat insulating coating material according to the present invention has good heat insulating properties and sound insulation / sound insulation properties by including a high content of hollow beads, and at the same time, can maintain mechanical properties and chemical properties as a paint. . Therefore, miscibility at the time of manufacture, storage stability after manufacture, paintability at the time of use, hardness and impact resistance after coating film formation, adhesion to a substrate, and the like can be ensured.

  The present invention is not limited to application to buildings, and can be used for various purposes such as heat insulation / sound insulation for vehicles, ships, electrical appliances, etc., insulation of reservoirs / pools, prevention of condensation in warehouses, etc. Can play.

  In addition, since the material is cheaper than conventional heat insulating materials such as glass wool, and the construction is performed by application, the work load of the heat insulation work is reduced, and the construction cost can be reduced. By applying the present invention, it is possible to contribute to a significant reduction in running cost such as power consumption and water charges.

  The heat-insulating coating material according to the present invention includes hollow beads, an acrylic resin emulsion, and a function-retaining agent, and the hollow beads are 45 to 50% by volume of the total capacity. It contains a conditioner, a film forming aid and an antifoaming agent. Hereinafter, each component will be described in detail.

  The hollow bead has a spherical shell, the inside of the shell is hollow, and the shell is porous and sealed, but in the present invention, it is sealed to enhance heat insulation and to ensure strength. Use what was done. In addition, when the cavity is filled with a gas such as air, the strength against a load such as compression is increased, but for the heat insulation and the sound insulation, the cavity is preferably vacuumed or decompressed. Examples of the shell material include resin, glass, and ceramic. Any hollow beads of material can be applied to the heat insulating coating material of the present invention.

  Examples of the ceramic hollow beads include titanium oxide and silica. Examples of the resin-made hollow beads include acrylic resin, epoxy resin, silicone resin, fluororesin, and the like, which are lighter than those made of ceramic. In particular, hollow beads of acrylonitrile resin excellent in heat resistance and strength are suitable. As the acrylonitrile-based resin hollow beads, for example, there is a trade name “ZEEOSPHERES TYPE W-210 (trademark: manufactured by 3M, USA)”. The average particle size of the hollow beads is about 5-15 μm. Specific gravity is about 0.23 in the case of acrylonitrile-based resin.

  In the heat insulating coating material of the present invention, the hollow beads are mixed so as to be 45 to 50% by volume of the total volume of the coating material and uniformly dispersed in the state before coating after completion of the production process. After coating, moisture, etc. gradually evaporate, and the latex particles of the acrylic resin in the emulsion approach and fuse together to form a uniform acrylic resin coating, and the hollow beads are uniformly dispersed in the coating. Filled form. When the coating film is formed by coating, the ratio of the hollow beads to the coating film varies depending on the vaporization of water and / or volatile components, but initially the hollow beads are 55 to 70% by volume of the total volume in that state. Determine the amount of composition distribution.

  The acrylic resin emulsion that plays the role of a vehicle as a coating material is one of water-based emulsion paints mainly composed of resin latex particles, and usually contains about 40 to 50% of water. Water-based emulsion paints are preferred as environmentally friendly paints compared to conventional solvent-based paints. In the case of a room temperature dry type, the latex particles are fused together to form a coating film when the water around the latex particles is vaporized. Acrylic resins include acrylic acid esters or methacrylic acid esters such as ethyl acrylate, n-butyl acrylate, n-butyl methacrylate, 2-acetoacetoxyethyl methacrylate, or acrylic acid, 2-acrylamido-2-methylpropane sulfone. There are copolymers of acid monomers such as acids. For example, there are a styrene / acrylic copolymer resin system and a vinyl acetate / acrylic copolymer resin system.

  Moreover, when using the heat insulating coating material by this invention as an adhesive agent, what has the reactive functional group which exhibits adhesiveness as a main component resin of an acrylic resin emulsion is employ | adopted. The heat-insulating coating material according to the present invention can impart a function according to its specific application to the acrylic resin emulsion.

  As described above, the heat-insulating coating material of the present invention contains hollow beads having a higher content than conventional ones, and therefore contains a function maintenance agent for maintaining the functions of the coating material according to mechanical properties and chemical properties. To do. By these, the viscosity, elasticity, adhesion and the like of the coating film are maintained at appropriate levels. Further, in the production process, the miscibility of the hollow beads is improved and a uniform dispersion state is realized. Furthermore, the coating workability at the time of coating and the mechanical strength and weather resistance of the coating film after drying are ensured. As the function maintaining agent, at least a high boiling point oil, a viscosity adjusting agent, a film forming aid and an antifoaming agent are used.

  The high boiling point oil is used for improving the miscibility between the hollow beads and the acrylic resin emulsion as an oily medium. For example, it can be selected from organic substances generally called high-boiling oils such as phosphoric acid esters, phthalic acid esters, acrylic acid esters, methacrylic acid esters, and other carboxylic acid esters.

  Viscosity modifiers ensure coating workability (for example, sprayability, etc.), as well as maintain coating thickness and mechanical strength after coating and drying, as well as wettability and adhesion to substrates. Used. For example, there are calcium carbonate, clay, diatomaceous earth, zeolite, magnesium carbonate and the like. A thickener may be included for the same purpose as the viscosity modifier. Examples of the thickener include methyl cellulose and hydroxyethyl cellulose.

  The film forming auxiliary ensures that water is gradually evaporated over a certain time after coating, and latex particles in the emulsion are fused to form a film. It is known that cracks are likely to occur in the drying process even in a general water-based emulsion paint, but particularly when a high content of hollow beads is included as in the present invention, a film forming aid is used in the drying process. It is important that the viscosity transition is performed appropriately. As film forming aids, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (texanol), (poly) ethylene glycol or (poly) ethylene glycol monoalkyl ether, (poly) ethylene glycol ester Or (poly) ethylene glycol ether ester, (poly) propylene glycol or (poly) propylene glycol monoalkyl ether, (poly) propylene glycol ester or (poly) propylene glycol ether ester, and the like.

  The antifoaming agent makes it difficult for foams that are likely to occur when the emulsion is stirred, reduces the generation of foams, and facilitates the elimination of the generated foams. In an aqueous emulsion, since a surfactant is often included, bubbles tend to be generated particularly easily. Examples of the antifoaming agent include silicon emulsions such as dimethylpolysiloxane and polyether-modified dimethylpolysiloxane, or the same aqueous resin.

  In addition to the above function maintenance agent, depending on the purpose of use of the heat-insulating coating material, white pigments such as titanium dioxide, calcium carbonate, kaolin, etc., which are usually used in paints, and colors such as carbon black, bengara, cyanine blue, etc. You may mix | blend other additives, such as pigments, such as a pigment, a plasticizer, a solvent, a dispersing agent, and antiseptic | preservative.

  Table 1 shows the component composition of one example of the heat insulating coating material according to the present invention. The materials in the table were charged into a stirrer and stirred and mixed until uniform.

  The heat insulating coating material obtained above was applied to form a coating film (0.6 mm thick), and the thermal conductivity of this coating film was measured. As a result, it was 0.16 W / mK.

Claims (3)

  A heat insulating coating material comprising hollow beads, an acrylic resin emulsion, and a function-retaining agent, wherein the hollow beads are 45 to 50% by volume of the total capacity, and high-boiling oil, viscosity as the function-retaining agent A heat-insulating coating material comprising a regulator, a film-forming aid, and an antifoaming agent.   2. The heat insulating coating material according to claim 1, wherein the hollow beads are 55 to 70% by volume of the total capacity after coating and drying of the heat insulating coating material.   The heat insulating coating material according to claim 1 or 2, wherein the hollow beads are vacuum hollow beads made of acrylonitrile resin.