JP2013087228A - Ultraviolet/near-infrared ray shielding aqueous coating material, heat-shielding treatment glass on which coating film formed of the coating material is formed, and method for subjecting window glass to heat-shielding treatment using the coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a superior ultraviolet/near-infrared ray shielding aqueous coating material which rapidly and easily imparts an ultraviolet/near-infrared ray shielding function to window glass or the like by only being applied to existing window glass or the like, and which forms a coating film having high adhesion and excellent chemical resistance and weatherability.SOLUTION: The ultraviolet/near-infrared ray shielding aqueous coating material is used for forming a coating film exhibiting an ultraviolet/near-infrared ray shielding function on an object to be coated. In the coating material, a polycarbonate polyurethane aqueous emulsion resin as a main component, a normal temperature curable coating film forming resin which uses in combination at least one of an aqueous isocyanate curing agent, a polycarbodiimide curing agent, an oxazoline curing agent or an epoxy curing agent, as a curing aid, by externally adding the agent, an ultraviolet ray absorber, and an inorganic near-infrared ray absorber are contained in an aqueous medium in a dispersed state. The an inorganic near-infrared ray ultraviolet absorber is fine particles of one selected from the group comprising antimony-doped tin oxide, antimony-doped zinc oxide, gallium-doped zinc oxide and tin-doped indium oxide. A heat-shielding treatment glass having a coating film formed of the coating material thereon and a method for subjecting window glass to a heat-shielding treatment using the coating material are also provided.

Description

  The present invention shows, for example, an indoor temperature-inhibiting product that can effectively block ultraviolet rays and near-infrared rays by simply applying it to glass for building materials and glass for vehicles. The present invention relates to an ultraviolet / near-infrared blocking water-based paint that also exhibits an effect of preventing discoloration of vehicle interior equipment, a heat-shielding glass using the paint, and a heat-shielding method for window glass.

  In recent years, with the mass consumption of fossil resource fuels due to industrial development, the amount of greenhouse gases such as carbon dioxide has been rapidly increasing, and global warming, which is thought to be caused by these greenhouse gases, has been rapidly progressing on a global scale. It has become an issue. The rise in temperature is said to be related to droughts, heavy rains, rising sea levels, and to affect the ecosystem, and there is an urgent need for “environmental measures” to curb fossil fuel consumption. . Furthermore, in urban areas, due to the so-called heat island phenomenon in summer, the air temperature is high not only during the daytime but also at night, so it is necessary to rely on cooling, and a vicious cycle occurs in which the temperature rises further due to exhaust heat from the cooling equipment. ing. That is, an increase in greenhouse gas accompanying an increase in the amount of cooling power used has spurred global warming and is considered to cause a further increase in temperature, and “energy saving measures” are urgently needed. On the other hand, various “energy-saving measures” have been taken to reduce the amount of electricity used for cooling as much as possible, such as improving the heat insulation of buildings, especially in urban areas.

  According to the current Building Standard Law, houses and commercial buildings need to be provided with openings having an area of 1/7 or more of the floor area on the wall. Generally, from the viewpoint of lighting, the area of the wall surface is 30 to 80. % Is considered to be window glass. It is said that the heat intrusion into the room in Japan in the summer is about 70% or more from the window glass, and the heat release from the room in Japan in the winter is also said to be about 50% or more from the window glass. ing. The sunlight that passes through the window glass is composed of ultraviolet rays, visible rays, and near infrared rays (heat rays), and the energy ratio thereof is 5% for ultraviolet rays, 45% for visible rays, and 50% for near infrared rays. This means that if a technology capable of blocking ultraviolet rays and near infrared rays that pass through the window glass can be developed by a simple method, the solar energy can be blocked by 55% without any problem with respect to lighting. And if the near infrared rays which permeate | transmit a window glass can be interrupted | blocked, the temperature in a house or a commercial building can be maintained comfortably, and it will lead to suppression of the usage-amount of air conditioning heating power. In addition, ultraviolet rays, which are also called actinic rays, cause a chemical reaction and cause discoloration and deterioration of the interior decoration. Degradation can be effectively suppressed. In addition, there is a similar problem with the window glass of vehicles such as automobiles.In particular, because of the narrow space, the temperature rise and temperature drop inside the vehicle when parked outdoors in summer and winter are significant, and indoors In automobiles and the like in which precise electronic devices are required to be mounted, it is very useful if the near infrared rays and ultraviolet rays that pass through glass can be blocked by a simple method.

  In recent years, heat shielding glass such as heat insulating glass and heat shielding laminated glass has been developed by glass manufacturers as a heat shielding measure against sunlight transmitted through the window glass. A film manufacturer has also developed a thermal barrier film that is applied to an existing window glass. However, heat-shielding glass, especially heat-shielding laminated glass, is expensive, so even now that “energy saving” is being sought, it is currently only popular in some new properties. On the other hand, although heat-insulating films are simple, there are problems in maintenance such as durability and cleaning, or because it is necessary to stick to existing window glass with high durability, it is a mold glass with uneven surfaces The current situation is that it is not widely used because it is difficult to apply to glass and mesh glass.

  To solve the above problems, it is possible to apply heat-shielding paint (light-shielding paint) to the window glass as a simpler method for imparting heat-shielding properties to the window glass than conventional heat-shielding glass and heat-shielding films. Has been. For example, there is a proposal for a solvent-based paint obtained by adding an ultraviolet absorber and a near-infrared absorbent as coating film formation subelements to an acrylic resin and an acrylic siloxane crosslinkable reactive polymer (Patent Document 1). In addition, an ultraviolet absorber and an inorganic near infrared absorber are dispersed and dissolved in an acrylic resin and an acrylic siloxane crosslinkable reactive polymer, and the inorganic near infrared absorber is a group of indium oxide, tin oxide and zinc oxide. There is a proposal for a solvent-based paint characterized by comprising one or more fine particles selected from (Patent Document 2). Patent Document 2 describes that tin-doped indium oxide fine particles and zinc oxide fine particles are used as the inorganic near-infrared absorber.

  Also, a heat ray blocking composition and a method for producing the same, which are related to a technique that enables the mass production of a coating film having high visible light transmittance and very excellent heat ray blocking characteristics using conductive fine particles having a heat ray blocking effect. (Patent Document 3). In the technique described in Patent Document 3, a dispersion sol produced by dispersing in a high concentration in an amphiphilic solvent without a separate powder production process for hydrophobizing the surface of conductive fine particles is a hydrous / alcohol-based, It is said that an anhydrous resin binder, a heat-shielding film and a molded article having excellent usability and stability can be produced at low cost.

Japanese Patent Laid-Open No. 10-088039 JP 2007-106826 A Japanese Patent No. 4347814

  However, normally used near-infrared absorbers are anfra compounds, organic aminium compounds (930 to 960 nm), cyanine compounds (600 to 1,000 nm), naphthalocyanine compounds, anthraquinone compounds (700 to 1,300 nm), polymethine compounds, diimonium compounds (1,080 to 1,110 nm) and the like. Although Patent Document 2 describes a near-infrared absorber composed of fine particles, the paint described in Patent Document 2 is an organic solvent such as toluene and xylene, which is an organic solvent, like the paint described in Patent Document 1. It is a solvent-based one that uses a solvent, and when applied to indoor window glass, there is a significant odor problem, and aromatic organic solvents can be harmful to health and improve safety as well. There was room.

  In addition, the technology described in Patent Document 3 mentioned above is capable of mass-producing a coating with excellent heat ray blocking characteristics at low cost, but after applying the heat ray blocking composition to the substrate, heating, A cured coating film is formed by irradiating ultraviolet rays, and the coating film is not formed indefinitely after being simply applied to glass or the like, so that there is a problem in use as a paint that can be easily used for general households. Furthermore, the paint described in Patent Document 3 uses an organic solvent that is amphiphilic to water / oil, specifically, an ether that is a volatile solvent as a main component. As with the paints described, there are problems of odor and health impairment, and improvements are required.

  Therefore, the object of the present invention is to solve the above-mentioned problems, and by simply applying it to a window glass or the like, it is possible to impart an excellent ultraviolet / near infrared ray blocking function to the window glass or the like quickly and easily. In addition, the paint coating film to be formed provides an ultraviolet / near-infrared water-resistant paint having high adhesion and excellent chemical resistance and weather resistance. In addition, the object of the present invention is to be able to simply and easily form a coating film that provides an excellent ultraviolet / near-infrared blocking effect by simply applying it to a window glass and the like, and it does not contain an organic solvent. The object of the present invention is to provide a heat-shielding technology excellent in the working environment and safety and health after application.

  The above object is achieved by the present invention described below. That is, the present invention is an aqueous paint for forming a coating film having a function of blocking ultraviolet rays and near infrared rays on an object to be coated, comprising a polycarbonate polyurethane aqueous emulsion resin as a main component, as a curing aid, Room-temperature-curing film-forming resin that uses at least one of an aqueous isocyanate curing agent, polycarbodiimide curing agent, oxazoline curing agent, or epoxy curing agent in combination, an ultraviolet absorber, and an inorganic near-infrared absorption And the inorganic near-infrared absorber is selected from the group consisting of antimony-doped tin oxide, antimony-doped zinc oxide, gallium-doped zinc oxide, and tin-doped indium oxide. The present invention provides an ultraviolet / near-infrared shielding water-based paint characterized by being one or more kinds of fine particles.

The following are mentioned as a preferable form of this invention.
The inorganic near-infrared absorber is added as an aqueous dispersion in which fine particles of 100 nm or less are dispersed in water, and the content thereof is 10 parts by mass with respect to 100 parts by mass of the coating film-forming resin component. An ultraviolet / near-infrared blocking water-based paint having a mass of 200 parts by mass.
An ultraviolet / near-infrared blocking water-based paint containing the polycarbonate polyurethane aqueous emulsion resin in an amount of 3 to 70% by mass.
The content of the ultraviolet absorber is added as an aqueous dispersion in which fine particles are dispersed in water, and is in the range of 5 to 50 parts by mass with respect to 100 parts by mass of the coating film-forming resin. Infrared shielding water-based paint.
An ultraviolet / near-infrared blocking water-based paint, wherein the ultraviolet absorber is an organic ultraviolet absorber using a benzotriazole-based and / or hydroxyphenyltriazine-based and a hindered amine-based radical scavenger in combination.
An ultraviolet / near-infrared blocking water-based paint which is an inorganic aqueous dispersion having a particle size distribution of 50 to 100 nm, wherein the ultraviolet absorber contains any one of cerium oxide, zinc oxide, iron oxide and titanium oxide.

  As another embodiment, the present invention is characterized in that a coating film made of any one of the above ultraviolet / near-infrared blocking water-based paints is formed on at least one surface of a plate-like inorganic glass or organic glass. The heat-shielding glass is provided.

  Furthermore, the present invention provides, as another embodiment, a window glass characterized in that a coating film is formed by applying any one of the above ultraviolet / near-infrared blocking water-based paints to the inner or outer surface of an existing window glass. A heat-shielding method is provided.

  The ultraviolet and near-infrared blocking water-based paint of the present invention has a finely divided ultraviolet absorber and near-infrared absorber dispersed well in a polycarbonate polyurethane aqueous emulsion. With the added curing agent, a coating film having a crosslinked structure can be easily formed at room temperature, and the coating film is excellent in adhesion, water resistance and chemical resistance, and at the same time, an ultraviolet absorber and The near-infrared absorber is well dispersed in the coating film. For this reason, when the ultraviolet ray and near infrared ray shielding water-based paint of the present invention is applied to a window glass or the like, it is possible to easily form a coating film excellent in adhesion, water resistance and chemical resistance, Since the ultraviolet and infrared absorbers are finely dispersed in a good state, they do not impair the original functions of the glass, are transparent and have excellent landscape visibility. Infrared rays are effectively blocked. That is, according to the present invention, the transparent and good landscape visibility is maintained on the glass surface simply by applying the ultraviolet / near infrared blocking water-based paint provided by the present invention to the inner or outer surface of the existing window glass. In the state, a coating film excellent in adhesion, water resistance and chemical resistance can be formed quickly and easily, and achieved by the coating film, in particular, a heat shielding effect by blocking infrared-near infrared rays Furthermore, by blocking the ultraviolet rays, it can be expected to prevent insects that prefer ultraviolet rays, and to prevent discoloration of furniture such as furniture in buildings and interior equipment of vehicles.

It is a figure which shows the spectrophotometric spectrum of the coating material which apply | coated the ultraviolet-ray and near-infrared shielding water-based coating material of this invention.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments of the present invention.
The ultraviolet / near-infrared blocking water-based paint of the present invention (hereinafter sometimes simply referred to as “paint”) has a coating film-forming component as an essential component of a polycarbonate polyurethane water-based emulsion, and a curing aid is externally added. In addition, organic / inorganic ultraviolet absorbers and inorganic infrared absorbers are added as essential components as coating film formation sub-elements, and these are finely dispersed in an aqueous medium. There is a basic configuration.

  As a result of intensive studies to solve the problems of the prior art described above, the present inventors used an aqueous dispersion of a polycarbonate polyurethane resin as an essential component as a resin component for forming a coating film. As an inorganic near-infrared absorber, one or more fine particles selected from the group consisting of antimony-doped tin oxide, antimony-doped zinc oxide, gallium-doped zinc oxide and tin-doped indium oxide are finely dispersed, and further, organic or inorganic In addition to these, at least one of an aqueous isocyanate curing agent, a polycarbodiimide curing agent, an oxazoline curing agent or an epoxy curing agent is added as a curing aid for the resin. By combining the above, it has been found that a useful ultraviolet / near-infrared blocking water-based paint can be obtained, leading to the present invention. It was.

  The ultraviolet / near-infrared blocking water-based paint of the present invention contains a polycarbonate polyurethane aqueous emulsion as a film-forming resin component and a curing agent as its curing aid. In addition, a coating film excellent in adhesion and weather resistance can be formed quickly and easily. In the coating material of the present invention, since the ultraviolet absorber and the near-infrared absorber are well dispersed in the aqueous emulsion, and both are dispersed in a good state in the formed coating film. Can absorb and block ultraviolet rays and near infrared rays suitably, and as a result, excellent heat shielding properties and the like can be realized. Hereinafter, the constituent materials of the present invention will be described.

<Coating element>
(Polycarbonate polyurethane aqueous emulsion resin)
In the present invention, a polycarbonate polyurethane aqueous emulsion resin obtained by emulsion polymerization of polycarbonate polyol and polyisocyanate is used as a coating film forming element. The polycarbonate polyol is preferably a polycarbonate diol, more specifically, a dealcoholization condensation reaction between a low molecular diol and a dialkyl carbonate, a dephenol condensation reaction between a low molecular diol and a diphenyl carbonate, or a low molecular diol. Examples thereof include those obtained by deglycolization condensation reaction with alkylene carbonates and dialkyl carbonates. In the ultraviolet / near infrared blocking water-based paint of the present invention, the polycarbonate polyurethane aqueous emulsion resin obtained as described above is in the range of 3% by mass to 70% by mass, more preferably 20% by mass to 50% by mass. It is good to contain in the range of%.

  Examples of low molecular diols used in the above reaction include 1,4-butanediol, 1,6-hexanediol, ethylene glycol, propylene glycol, 3-methyl-1,5-pentanediol, neopentyl glycol, diethylene glycol, 1, Examples include 4-cyclohexanediol and 1,4-cyclohexanedimethanol. Dialkyl carbonates include dimethyl carbonate and diethyl carbonate. Moreover, ethylene carbonate is mentioned as alkylene carbonate. In the present invention, as the polycarbonate polyol, poly (hexamethylene carbonate) diol obtained by a condensation reaction of 1,6-hexanediol and diethyl carbonate is particularly preferable. The number average molecular weight of the polycarbonate polyol used in the present invention is preferably 500 to 4,000, particularly preferably 1,000 to 2,000.

  As the polyisocyanate used in the above reaction, a diisocyanate having two isocyanate groups is particularly preferable. Diisocyanates include aromatic, aliphatic and alicyclic diisocyanates. Specifically, hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, xylylene diisocyanate, 1,4-phenylene diisocyanate, 1,3-phenylene diisocyanate, 2,4- Examples include tolylene diisocyanate, 2,4 / 2,6-tolylene diisocyanate mixture, 4,4′-diphenylmethane diisocyanate, isopropylidene-bis (4-phenyl isocyanate), naphthalene diisocyanate, and the like. These can be used individually or in mixture of 2 or more types.

  In order to obtain a polycarbonate polyurethane aqueous emulsion resin suitable for the present invention, a chain extender can be used in combination. As the chain extender, a compound having two or more active hydrogen-containing groups such as an amino group and a hydroxyl group and having a molecular weight of less than 500 is preferable, and a compound having a molecular weight of 300 or less is particularly preferable. For example, dihydric alcohols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol, trihydric alcohols such as trimethylolpropane and glycerin, ethanolamine, Amino alcohols such as aminopropyl alcohol, 3-aminocyclohexyl alcohol, p-aminobenzyl alcohol, ethylenediamine, 1,2-propylenediamine, 1,4-butylenediamine, 2,3-butylenediamine, hexamethylenediamine, cyclohexane Diamines such as diamine, piperazine, xylylenediamine, tolylenediamine, phenylenediamine, diphenylmethanediamine, 3,3'-dichlorodiphenylmethanediamine, hydrazine, monoalkylhydride Jin, 1,4-hydra hydrazines of Gino diethylene such as carbohydrazide, dihydrazide such as adipic acid hydrazide and the like are used. Among these, polyhydric alcohols are preferable, and dihydric alcohols are particularly preferable.

  The polycarbonate polyurethane aqueous emulsion resin used in the present invention can be prepared by the conventionally known methods as described above using the materials as described above, but commercially available products as listed below are appropriately used. You can also. For example, Takelac W-635 (manufactured by Mitsui Chemicals), Eternacol UW-3100 (manufactured by Ube Industries), Eternacol UW-5502 (manufactured by Ube Industries), and the like can be mentioned.

(Curing aid)
The ultraviolet / near-infrared blocking water-based paint of the present invention comprises a room-temperature-curing film-forming resin comprising the polycarbonate polyurethane aqueous emulsion resin described above as a main component and a curing aid added thereto. It is characterized by. That is, the coating material of the present invention is configured not to use only the polycarbonate polyurethane aqueous emulsion resin as a film-forming component, but to externally mix a curing aid as described below into the above resin and then apply this. Thus, a coating film having excellent adhesion and weather resistance can be easily formed on a window glass or the like without performing a treatment such as heating. Examples of the curing aid include an aqueous isocyanate curing agent, a polycarbodiimide curing agent, an oxazoline curing agent, and an epoxy curing agent. At least one of these is externally added and used in combination with the polycarbonate polyurethane aqueous emulsion resin. As the addition amount, it is added in the range of 1 to 50 parts by mass, more preferably in the range of 5 to 20 parts by mass with respect to 100 parts by mass of the solid content in the polycarbonate polyurethane aqueous emulsion resin. preferable. By using the above-mentioned curing aid in combination, the water-based urethane resin and the curing aid can easily form a cross-linked structure simply by applying the paint of the present invention to a window glass and the like and leaving it at room temperature. As a result, a coating film that is excellent in various properties such as film hardness, chemical resistance, and water resistance, as well as excellent adhesion is formed. It is preferable that the above-described curing aid is added afterwards into a paint made of other constituent materials, for example, immediately before being applied to the window glass.

<Coating formation sub-element>
The ultraviolet / infrared shielding water-based paint of the present invention is applied to the coating film-forming element comprising the aqueous dispersion prepared as described above, as a coating film-forming sub-element, and as described below, an ultraviolet absorber and inorganic infrared absorption. The agent is well dispersed.

(UV absorber)
Examples of the organic ultraviolet absorber usable in the present invention include methyl salicylate, pt-butylphenyl-salicylate, p-octylphenyl-salicylate (hereinafter referred to as salicylic acid derivative), 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone (above, benzophenone series), 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′- Hydroxy-3′-t-butyl-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-amylphenyl) benzotriazole (above, benzotriazole series), 3 -Phenyl-7- (4'-methyl-5'-n-butoxybenzotriazolyl-2 -) Coumarin (coumarin type), 2'-ethylhexyl-2-cyano-3,3-diphenyl acrylate, etc. can be mentioned. These may be used alone or in combination of two or more. In particular, a combination of a benzotriazole type and a hydroxyphenyl triazine type, and a combination of any of these and a hindered amine type antioxidant are desirable. Benzotriazole has a high UV absorption effect, and when combined with hydroxyphenyltriazine, the UV absorption range is expanded. By combining these with a hindered amine antioxidant (radical scavenger), the stability of the UV absorber is improved. This is because (durability) increases.

  In the present invention, it is particularly preferable to use a water-based ultraviolet absorber. Examples of commercially available products include the following. Shineguard TA-04, Shineguard TA-22 (above, hydroxyphenyltriazine series, manufactured by Senka), Shineguard BZ-24, Shineguard BZ-07, Shineguard BZ-08 (above, benzotriazole series, Senca) Manufactured), Adecanol UC-3140 (benzotriazole series, manufactured by Adeka Corporation), Tinuvin 477DW (benzotriazole series, manufactured by BASF Corporation),

  Examples of inorganic ultraviolet absorbers that can be used in the present invention include inorganic fine particles such as zinc oxide, zirconium oxide, praseodymium oxide, cerium oxide, iron oxide, and titanium oxide. The addition amount of the ultraviolet absorber as described above is 5 to 50 parts by mass, preferably 10 to 20 parts by mass in the case of an organic ultraviolet absorber with respect to 100 parts by mass of the resin on a mass basis. In the case of using an inorganic ultraviolet absorber, a good ultraviolet absorption effect can be obtained by using 20 to 50 parts by mass, preferably 30 to 40 parts by mass. However, when the added amount of the ultraviolet absorber is too large, the transparency of the coating composition of the present invention may be hindered or the physical properties may be deteriorated when applied to a window glass or the like. Therefore, it is not preferable. On the other hand, when the amount is too small, a sufficient ultraviolet absorption effect may not be exhibited, which is not preferable. As the ultraviolet absorber used in the present invention, an inorganic aqueous dispersion having a particle size distribution of 50 to 100 nm is particularly suitable.

(Inorganic near-infrared absorber)
The ultraviolet / infrared shielding water-based paint of the present invention is required to contain the following inorganic infrared absorber as a coating film forming sub-element. That is, the ultraviolet / infrared shielding water-based paint of the present invention is selected from the group consisting of antimony-doped tin oxide, antimony-doped zinc oxide, gallium-doped zinc oxide and tin-doped indium oxide, which functions as an inorganic infrared absorber. It contains fine particles of seeds or more. Two or more of these can also be mixed and used. The addition amount of the above-described inorganic infrared absorber is not particularly limited, but is 10 to 200 parts by mass, desirably 20 to 50 parts by mass with respect to 100 parts by mass of the resin on a mass basis. As the inorganic near-infrared absorber used in the present invention, an aqueous dispersion in which fine particles of 100 nm or less are dispersed in water is particularly preferable. Examples of commercially available fine particles having such characteristics include the following. As a small particle size type ATO water dispersion in which antimony-doped tin oxide fine particles are dispersed in water, TDL-S (trade name, median diameter 50 to 85 nm, solid content concentration 17 to 18%) manufactured by Mitsubishi Materials Corporation, etc. There is. Further, as GZO of gallium-doped zinc oxide fine particles that can be dispersed in water, there is a passet GK (trade name, powder primary particle diameter 20 to 40 nm) manufactured by Hux Itec Co., Ltd., and ITO (tin-doped) that can be dispersed in water. Indium oxide) fine particles include VP ITO IR5 (trade name) manufactured by EVONIK, and zinc antimonate sol (primary particle diameter 15 nm to 20 nm) dispersible in water is manufactured by Nissan Chemical Co., Ltd. Cellnax CX-Z330H-F2 (trade name) and the like can be mentioned, and any of them can be suitably used in the present invention.

(Other additives)
The ultraviolet / infrared shielding water-based paint of the present invention may further be appropriately combined with additives such as a leveling agent, a surfactant, a silane coupling agent, an antifoaming agent, a colorant, and an antioxidant as necessary. Good.

<Use of ultraviolet / infrared shielding water-based paint of the present invention>
(Coating object)
The material to which the paint of the present invention is applied is not particularly limited as long as it is a transparent substrate, but is usually applicable to a transparent substrate for window glass of organic glass such as inorganic glass or acrylic resin or polycarbonate. The effect (especially energy saving) by the heat insulation aimed at by the present invention is increased, which is desirable. In addition, a method of coating a film having a thickness of 50 to 200 microns having a weather resistance such as a polyester film, an acrylic film, a polycarbonate film, a fluorine film, and a polyimide film and applying an adhesive process to the glass surface is also possible. .

(Coating method of the present invention)
The coating method of the present invention is not particularly limited, but when applied to an existing window glass, a so-called flow coating is applied by supplying a sponge coat, a spray coat or an excess paint to the upper end portion and flowing down. Is preferred. In addition, in the case of factory coating, curtain coating (flow coating) is also possible in addition to these coating methods. In the case of coating on a film, the paint of the present invention is diluted to an appropriate viscosity and then coated with a coater such as a gravure coater, comma coater, roll coater, or Mayer bar coater.

  The coating thickness is 2 to 16 μm, desirably 4 to 12 μm, and more desirably 8 to 10 μm after drying. If it is too thin, it will be difficult to give the window glass the ultraviolet ray / heat ray blocking effect obtained by the paint of the present invention.If it is too thick, the cost will be high, and the visible light transmittance will be reduced, and the transparency of the window glass will be reduced. Since there is a possibility of inhibiting, it is not preferable. In addition, in the above, the application surface is usually one side, but may be both sides. In the case of an existing window glass, it is desirable to apply to the inner surface (interior surface) on the second floor or more because the construction is easy.

Since the ultraviolet / near-infrared blocking water-based paint of the present invention is configured as described above, the following effects can be obtained.
Because it is a water-based paint containing a room-temperature-curing film-forming resin, it can easily obtain UV / NIR shielding effects simply by applying to conventional glass, etc. There is no need to replace it. Furthermore, since it is a room temperature curing type, the base material does not have to be inorganic glass, and can be applied to organic glass roofs (for example, garage roofs and sun visors), and can be applied to a wide range of objects to be coated. Expansion of applications is expected. In order to block ultraviolet rays and near infrared rays (heat rays), when applied to window glass or the like, transmission of ultraviolet rays and heat rays through the window glass is suppressed, and the temperature change in the room becomes gentler than before. That is, the temperature rise in the room in summer, and conversely, the temperature drop in the room in winter is less than that in the case of using a conventional window glass, and cooling and heating can be saved, leading to energy saving.

  Examples and comparative examples performed for confirming the effects of the present invention will be described below. Unless otherwise specified, the blending unit is a mass unit.

[Example 1]
In this example, an ATO aqueous dispersion of a small particle size type in which antimony-doped tin oxide fine particles are dispersed in water as an inorganic near-infrared absorber (trade name: TDL-S, manufactured by Mitsubishi Materials Corporation, median diameter 50 to 85 nm) , Solid content concentration 17-18%). And 50 parts of this ATO aqueous dispersion and 40 parts of urethane dispersion (trade name: Takelac W-635, manufactured by Mitsui Chemicals) which is a coating film forming resin were mixed and stirred for 30 minutes. The above bamboo rack W-635 is a water-based urethane resin in which a polycarbonate polyurethane elastomer is dispersed in water. Thereafter, to the resulting stirred mixed liquid, Adecanol UC-3140 (trade name, water dispersion type light stabilizer (aqueous dispersion of benzotriazole-based UV absorber) commercially available as an additive for synthetic resin emulsion) was added. 5 parts of Adeka Co., Ltd., particle size 90 to 150 nm) and 0.5 part of an antifoaming agent (trade name: BYK-028, manufactured by BYK Chemie) were added and stirred for another 30 minutes.

  10 parts of a water-dispersible polyisocyanate (trade name: Takenate WD-725, manufactured by Mitsui Chemicals) was externally added to 100 parts of the obtained mixed liquid as an aqueous isocyanate-based curing agent, and mixed and stirred. A paint coating film was prepared as follows. Takenate WD-725 used above is a soap-free water-dispersible polyisocyanate that easily disperses in water by imparting a nonionic hydrophilic group to the polyisocyanate compound. It reacts to form a crosslinked structure with the aqueous urethane resin. The coating film obtained by mixing and stirring the above was applied on a plate glass using a bar coater # 20, dried, allowed to stand at room temperature, and various physical properties of the coating film formed after one week. evaluated. Evaluation methods and results will be described later. In addition, about the near-infrared absorptive water-based coating material of another example, after obtaining the coating material, the coating film was formed and evaluated.

[Example 2]
In this example, a small particle size type GZO aqueous dispersion (trade name: Pazette GK 30% liquid: manufactured by Hakusuitec Co., Ltd.) in which gallium-doped zinc oxide fine particles were dispersed in water was used as an inorganic near infrared absorber. . Then, 40 parts of the GZO aqueous dispersion and 30 parts of polycarbonate polyurethane dispersion (trade name: Eternacol UW-3100, manufactured by Ube Industries), which is a coating film-forming resin, were mixed and stirred for 30 minutes. Thereafter, Adecanol UC-3140 (trade name, manufactured by ADEKA CORPORATION), which is a commercially available water-dispersed light stabilizer (an aqueous dispersion of an ultraviolet absorber), which is commercially available as an additive for synthetic resin emulsions, was added to the resulting stirred mixed liquid. ) 5 parts and 0.5 part of antifoaming agent (trade name: BYK-028, manufactured by BYK Chemie) were added, and 5 parts of isopropyl alcohol was further added, followed by stirring for 30 minutes. To 100 parts of the obtained mixed liquid, 10 parts of carbodilite E-03A (trade name, manufactured by Nisshinbo Chemical Co., Ltd.), which is a carbodiimide-based curing agent, was externally added and mixed and stirred to obtain the coating material of Example 2. A coating film was prepared in the same manner as in the case. The carbodilite E-03A used above is a soap-free type that is easily dispersed in water, and forms a crosslinked structure with the aqueous urethane resin in water at room temperature.

[Example 3]
As an inorganic near-infrared absorber, the ATO aqueous dispersion (trade name: TDL-S, manufactured by Mitsubishi Materials Corporation, median diameter 50 to 85 nm, solid content concentration 17 to 18%) used in Example 1 was used. 50 parts of an aqueous dispersion and 30 parts of polycarbonate polyurethane dispersion (trade name: Eternacol UW-5502, manufactured by Ube Industries), which is a coating film-forming resin, were mixed and stirred for 30 minutes. Thereafter, Tinuvin 477-DW, which is an aqueous dispersion obtained by dispersing a hydrophobic HPT ultraviolet absorber, which is commercially available as an additive for aqueous coating, in the polymer, is dispersed in the obtained stirring mixture. (Product name, manufactured by BASF Co., Ltd.) 5 parts and 0.5 part of antifoaming agent (trade name: BYK-028, manufactured by BYK Chemie) were added, and 5 parts of isopropyl alcohol was further added, followed by further stirring for 30 minutes. did. In the case of Example 1, 5 parts of Denacol EX614B (trade name, manufactured by Nagase ChemteX) was externally added to 100 parts of the obtained mixed liquid as an epoxy-based curing agent, and mixed and stirred to obtain the paint of Example 3. A paint coating film was prepared in the same manner as described above. Denacol EX614B used above is a soap-free type that is easily dispersed in water, and forms a crosslinked structure with the aqueous urethane resin in water at room temperature.

[Comparative Example 1]
In this comparative example, ATO powder (trade name: T-1, manufactured by Mitsubishi Materials Corporation), which is a powder material made of antimony-doped tin oxide fine particles, was used as the inorganic near infrared absorber. T-1 is said to have a primary particle diameter much smaller than the wavelength of visible light (400 to 800 nm), and a coating film having excellent transparency can be formed by a paint obtained by dispersing this. Is. 20 parts of the ATO powder and 50 parts of an acrylic emulsion (Polysol AP609N, Showa Polymer Co., Ltd.) are mixed, and further 10 parts of water, 10 parts of isopropyl alcohol, defoaming agent brand names BYK-028, BYK Chemie Co., Ltd. 0.5 parts) was added and stirred for 30 minutes. Thereafter, ATO powder was dispersed in an acrylic emulsion with 1 mmφ glass beads using a paint shaker. In the resulting dispersion, 5 parts of Adecanol UC-3140 (trade name, manufactured by Adeka Co., Ltd.), which is an aqueous dispersion of an ultraviolet absorber commercially available as an additive for paints, and an antifoaming agent (trade name: BYK) -028, manufactured by BYK Chemie) was added in an amount of 0.5 parts, and 5 parts of isopropyl alcohol was further added, followed by further stirring for 30 minutes. To 100 parts of the obtained mixed solution, 5 parts of Denacol EX521 (trade name, manufactured by Nagase ChemteX), which is a water-soluble and polyfunctional epoxy curing agent, was externally added and mixed and stirred to obtain the coating material of Comparative Example 1. A paint coating film was prepared in the same manner as in Example 1.

[Comparative Example 2]
In this comparative example, a paint was prepared in the same manner as in Example 1, except that 10 parts of water-dispersible polyisocyanate (trade name: Takenate WD-725, manufactured by Mitsui Chemicals) was not added. Using the obtained coating material, a coating film was formed in the same manner as in Example 1, and the coating film was evaluated. However, in one week, the coating surface was sticky and could not be evaluated.

[Evaluation]
The paint film formed with each of the paints of Examples 1 to 3 and Comparative Example 1 obtained above was used as a test piece and evaluated by the following method and criteria. As a result of visual observation, the paint film of any test piece was transparent, and the transparency of the plate glass was not impaired. Moreover, the coating film did not smell of an organic solvent.

1) Adhesion test Using a cutter knife, cut the coating film on the surface of the test piece into 1 mm square, make 100 lattices, desorb with cellophane tape (manufactured by Nichiban), and count the number of peeled coating films. It was. And the case where the number of peeled coating films was 5 or less was evaluated as (circle), and the result was shown in Table 1.

2) Hardness test In accordance with JIS K5600, the surface of each test piece was examined for scratches on the coating film by a hand scraping method using a hardness test pencil (Unipencil, manufactured by Mitsubishi Uni Co., Ltd.). And it evaluated by the hardness of the pencil with which each coating film was damaged, and the result was shown in Table 1.

3) Boiling water test After the test piece was immersed in boiling water for 1 hour, it was pulled up, the state of the coating film surface was examined, and the presence or absence of a whitened portion was evaluated. The results are shown in Table 1.

4) Alkali resistance test A 5% NaOH aqueous solution was dropped on each test piece, the state of the coating film surface after 8 hours was visually examined and evaluated with or without changes, and the results are shown in Table 1.

5) Acid resistance test A 5% acetic acid aqueous solution was dropped on each test piece, the state of the coating film surface after 8 hours was visually examined, evaluated by the presence or absence of changes, and the results are shown in Table 1.

6) Weather resistance test Each test piece was subjected to an exposure test using an eye super UV tester under two conditions of 100 hours exposure and 200 hours exposure, and the condition of the coating film surface after exposure was examined visually. The results are shown in Table 1. In the coating films obtained in the Examples, no deterioration was observed in any coating film, and no discoloration was observed in the coating film after 200 hours exposure. The coating film obtained in Comparative Example 1 was discolored after 100 hours of exposure, and the film was deteriorated after 200 hours of exposure.

[Spectrum measurement]
A glass coating formed on the plate glass with the paint of Example 1 was collected, and the spectrum of the coating was measured under the following conditions using a spectrophotometer, and the obtained spectrum is shown in FIG. The spectrophotometer used in this case is Hitachi U3410 (trade name, manufactured by Hitachi, Ltd.), and the measurement wavelength range is 300 nm to 2500 nm from the ultraviolet region to the near infrared region. As shown in FIG. 1, it was confirmed that transmission in the ultraviolet region and the near infrared region was suppressed even though the coated material was transparent.

  As shown in the above-mentioned Examples, the ultraviolet / near-infrared blocking water-based paint provided by the present invention is because the ultraviolet absorber and the near-infrared absorber are finely dispersed in an aqueous medium at, for example, 100 nm or less. Excellent infrared blocking effect and ultraviolet blocking effect. By coating the window glass with the ultraviolet / near infrared blocking water-based paint provided by the present invention, a coating film is formed quickly and easily, but the transparency of the window glass is not impaired, At the same time, by applying to the window glass, infrared-near-infrared rays are effectively cut off, so a heat shielding effect can be expected. Can also be expected. Furthermore, since the ultraviolet rays are blocked by applying the ultraviolet / near-infrared blocking water-based paint provided by the present invention to the window glass, the insect-repellent effect for preventing the propagation of insects that prefer ultraviolet rays indoors, furniture, etc. A sunburn preventing effect can also be obtained.

Claims (8)

A water-based paint for forming a paint film showing a function of blocking ultraviolet rays and near infrared rays on an object to be coated,
A room-temperature curable coating film comprising a polycarbonate polyurethane aqueous emulsion resin as a main component and externally adding at least one of an aqueous isocyanate curing agent, a polycarbodiimide curing agent, an oxazoline curing agent or an epoxy curing agent as a curing aid. A forming resin, an ultraviolet absorber, and an inorganic near-infrared absorber dispersed in an aqueous medium, and the inorganic near-infrared absorber comprises antimony-doped tin oxide, antimony-doped zinc oxide, An ultraviolet / near-infrared blocking water-based paint comprising at least one fine particle selected from the group consisting of gallium-doped zinc oxide and tin-doped indium oxide.   The inorganic near-infrared absorber is added as an aqueous dispersion in which fine particles of 100 nm or less are dispersed in water, and the content thereof is 10 parts by mass with respect to 100 parts by mass of the coating film-forming resin component. The ultraviolet / near-infrared shielding water-based paint according to claim 1, which is ˜200 parts by mass.   The ultraviolet / near-infrared shielding water-based paint according to claim 1 or 2, wherein the polycarbonate polyurethane aqueous emulsion resin is contained in a range of 3% by mass to 70% by mass.   The content of the ultraviolet absorber is added as an aqueous dispersion in which fine particles are dispersed in water, and is 5 to 50 parts by mass with respect to 100 parts by mass of the coating film-forming resin. 4. The ultraviolet / near-infrared shielding water-based paint according to any one of items 1 to 3.   The ultraviolet ray according to any one of claims 1 to 4, wherein the ultraviolet ray absorber is an organic ultraviolet ray absorber in which a benzotriazole type and / or hydroxyphenyl triazine type and a hindered amine type radical scavenger are used in combination.・ Near infrared blocking water-based paint.   The said ultraviolet absorber is an inorganic aqueous dispersion having a particle size distribution of 50 to 100 nm containing any one of cerium oxide, zinc oxide, iron oxide, and titanium oxide. The ultraviolet / near infrared blocking water-based paint described.   A coating film comprising the ultraviolet / near-infrared shielding water-based paint according to any one of claims 1 to 6 is formed on at least one surface of a plate-like inorganic glass or organic glass. Heat treated glass.   A method for heat-shielding a window glass, characterized in that a coating film is formed by applying the ultraviolet / near-infrared shielding water-based paint according to any one of claims 1 to 6 to an inner surface or an outer surface of an existing window glass. .