JPH10176120A - Primer coating material having heat-ray reflectivity and ultraviolet absorptivity and transparent body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a primer coating material which can form a film which reflects heat rays, intercepts ultraviolet rays and has improved adhesion, scratch resistance and durability by dispersing an ultraviolet absorber and a specified flaky aluminum powder in a primer coating material comprising a thermosetting acrylic resin. SOLUTION: A thermosetting acrylic resin in an amount of 5-10wt.% obtained by adding a radical-polymerization initiator to a solution containing a vinyl monomer and 2-50wt.% silane coupling agent and reacting the resultant mixture under heating is dissolved in an organic solvent such as diacetone alcohol or propylene glycol monomethyl ether to obtain a primer coating material. 5-15 pts.wt., per 100 pts.wt. thermosetting acrylic resin, ultraviolet absorber and a flaky aluminum powder having an average thickness of 0.05-2.0μm and a mean particle diameter of 5-55μm and used in such an amount that the ratio of the aluminum powder to the thermosetting acrylic resin to the organic solvent is 0.2:48:95 to 44:19:37 by weight are dispersed in above coating material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mainly used as a window material for vehicles such as automobiles, buildings, etc., for shielding heat rays (IR) generated by sunlight in a vehicle or a room to reduce heat and the like and to reduce ultraviolet rays (UV). The present invention relates to a useful heat-ray-reflecting ultraviolet-absorbing primer paint and a transparent body which are useful for shielding a person or interior material from sunburn by shielding the same.

[0002]

2. Description of the Related Art In recent years, transparent bodies having various heat ray reflecting capabilities have been proposed for transparent window materials capable of freely controlling sunlight energy. Conventionally, as a method of reflecting a heat ray, a method of forming a metal, an alloy, or a metal compound on a surface of a transparent resin body such as a polycarbonate by a method of sputtering, a method of vacuum deposition, or the like has been performed.

Al, Zn, Cu, A having heat ray reflection
A film obtained by vapor-depositing a metal such as g or Au on a transparent resin body such as polycarbonate is generally inferior in film strength and adhesion, so that a protective film such as SiO ₂ or Al ₂ O _{3 is} generally formed, or a transparent film is formed. It is necessary to provide a binder layer between the resin body and the vapor-deposited film, resulting in poor productivity and high cost.

[0004]

SUMMARY OF THE INVENTION In the present invention, as a method for producing an inexpensive heat-reflecting ultraviolet-absorbing transparent body, various studies have been made with a focus on a paint containing aluminum powder. That is, when the transparent resin is used as a window material for vehicles, buildings, etc., a protective thin film of a colloidal silica-containing organopolysiloxane paint is provided in order to improve weather resistance and scratch resistance. Is provided with an adhesive layer made of a thermosetting acrylic resin because of poor adhesion to a transparent resin. Further, an ultraviolet absorbing transparent substrate obtained by adding an ultraviolet absorbing agent to this adhesive layer has been known.

However, it has been difficult to incorporate aluminum powder into a protective thin film of a colloidal silica-containing organopolysiloxane paint. Therefore, an object of the present invention is to provide a primer paint having heat ray reflection and ultraviolet absorption by containing an aluminum layer and an ultraviolet absorber in an adhesive layer made of a thermosetting acrylic resin.

[0006]

Means for Solving the Problems The present inventors have studied a method of including an ultraviolet absorber and aluminum powder in a primer coating made of a thermosetting acrylic resin, and as a result, selected aluminum powder having a special shape. Moreover, by making the primer paint film a specific thickness, a primer paint having less glare and good heat-reflection ultraviolet absorption ability with good adhesion to the protective thin film of the colloidal silica-containing organopolysiloxane paint can be obtained. The present inventors have found that the present invention is obtained, and completed the present invention.

That is, according to the present invention, a primer coating comprising a thermosetting acrylic resin is added to an ultraviolet absorber and an average thickness of 0.05%.
Primer paint having heat-ray-reflecting / ultraviolet-absorbing performance obtained by adding and dispersing scaly aluminum powder having a mean diameter of 5 to 50 µm and a mean diameter of 5 to 50 µm. Further, the primer coating is applied as a dry coating on one surface of a transparent substrate so as to have a thickness of 1 to 10 μm and cured by heating, and then the organotrialkoxysilane, colloidal silica and solvent are coated on the thermosetting acrylic resin coating. This is a transparent body having heat ray reflection and ultraviolet absorption performance, which is coated by applying a colloidal silica-containing organopolysiloxane coating composed of and curing by heating to form a protective thin film.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The thermosetting acrylic resin used in the primer coating of the present invention includes methyl methacrylate, butyl methacrylate, alkyl methacrylates such as 2-ethylhexyl methacrylate, methyl acrylate, ethyl acrylate, alkyl acrylates such as butyl acrylate, glycidyl methacrylate, and acrylamide. , Acrylonitrile, vinyl acetate, ethyl vinyl ether, butyl vinyl ether, vinyl ether such as hexyl vinyl ether, at least one vinyl monomer exemplified by styrene, ethylene glycol dimethacrylate, vinyl triethoxysilane, vinyl tris (β-methoxy Ethoxy) silane, γ-glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N- Be those derived from at least one of (aminoethyl) .gamma.-aminopropyl silane coupling agents such as triethoxysilane, it is necessary to contain the silane coupling agent 2 to 50% by weight. If the amount of the silane coupling agent is less than 2% by weight, the resulting film will not be thermosetting, so that a large amount of the light stabilizer cannot be immobilized. Decrease significantly.

A thermosetting acrylic resin is prepared by adding a solution containing the above monomer and a silane coupling agent to a peroxide such as dicumyl peroxide or benzoyl peroxide or an azo compound such as azobisisobutyronitrile. Can be easily obtained by adding a radical polymerization catalyst selected from the above and reacting the mixture under heating.

A solvent is used for the primer coating. Examples of the solvent include diacetone alcohol, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether,
Isobutyl alcohol, isopropyl alcohol, n-
Butyl alcohol, n-propyl alcohol, xylene, toluene and the like can be mentioned. This primer coating is usually diluted with the above solvent and used as a 5 to 10% by weight solution of a thermosetting acrylic resin.

As the ultraviolet absorber used in the present invention, general ones are used, and examples thereof include benzophenone-based, benzotriazole-based, cyanoacrylate-based, triazine-based and salicylate-based. Particularly preferred are benzophenone ultraviolet absorbers, specifically, 2-hydroxy-4-n-octoxybenzophenone,
2-hydroxy-4-methoxybenzophenone, 2,2'-dihydroxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-Dihydroxy-4,4'-diethoxybenzophenone,2,2'-dihydroxy-4,4'-dipropoxybenzophenone,2,2'-dihydroxy-4,4'-dibutoxybenzophenone,2,2'-dihydroxy -4-methoxy-
4'-ethoxybenzophenone, 2,2'-dihydroxy-4-
Methoxy-4'-butoxybenzophenone, 2,4-dihydroxybenzophenone and the like.

The amount used is preferably 5 to 15 parts by weight with respect to 100 parts by weight of the thermosetting acrylic resin. If the amount is more than the above range, it precipitates on the coating film and the appearance becomes poor.
On the other hand, if the amount is too small, the desired ultraviolet absorbing ability cannot be obtained.

Further, the aluminum powder used in the present invention comprises:
It is scaly with an average thickness of 0.05 to 2.0 μm and an average diameter of 5 to 55 μm, more preferably 0.1 to 1.0 μm.
m and an average diameter of 5 to 30 μm. If it exceeds the above range, the glare is large and a sufficient shielding effect cannot be obtained. In addition, as the aluminum powder having a shape other than the above range, there is a spherical shape or the like, but since the effect of shielding heat rays is small as compared with the flake shape, it is necessary to increase the addition amount in order to improve the effect. The cost becomes high, and a coating film having good adhesion to the protective thin film of the colloidal silica-containing organopolysiloxane paint cannot be obtained, and the surface loses smoothness.

Since the above aluminum powder has a risk of dust explosion, it is traded as an aluminum paste dispersed in an organic solvent such as mineral spirit, toluene, and aromatic hydrocarbon. The amount of aluminum powder in the aluminum paste is 5
5 to 80% by weight. The aluminum paste that is added to and dispersed in the primer coating made of a thermosetting acrylic resin is classified into two types by using stearic acid and oleic acid as lubricating oils used when pulverizing into aluminum powder. In the case of stearic acid, there is a so-called leafing type in which aluminum powder is present near the surface of a coating film because of poor wettability with aluminum powder. In the case of oleic acid, there is a so-called non-leafing type which is present throughout the coating film because of its good wettability with aluminum powder. Of these, the non-leafing type is preferably used because the adhesiveness between the transparent substrate and the protective thin film of the colloidal silica-containing organopolysiloxane composition is better.

As a commercially available product, for example, SS-6246A
R, SS-5000AR (manufactured by Silver Line) and the like. Also, a colored aluminum paste obtained by chemically attaching an organic pigment to an aluminum piece can be suitably used, and commercially available products include, for example, LEPC-2 manufactured by Silver Line.
027 (green), 2061 (blue), 2626
(Gold) and 2276 (red).

The weight ratio of aluminum powder, thermosetting acrylic resin and organic solvent is 0.2: 4.8: 95-4.
4:19:37. If the amount is less than the above range, a sufficient shielding effect cannot be obtained, and if the amount exceeds the above range, a glittering feeling is large, and a coating film having good adhesion with the protective thin film of the colloidal silica-containing organopolysiloxane paint is obtained. Absent.

The primer paint of the present invention having a heat ray reflection ultraviolet ray absorbing ability is prepared by adding a UV absorber and an aluminum paste to a solution obtained by dissolving a thermosetting acrylic resin in an organic solvent, and using a sand mill, a ball mill, a roll mill homogenizer or the like. It is manufactured by mixing.

As the transparent substrate used in the present invention, polycarbonate resin, polymethyl methacrylate resin and the like can be mentioned, and a usual film or sheet shape is used, and the thickness is not limited. In addition, as the above-mentioned film or sheet, a surface selected from performances such as anti-fogging, anti-static and abrasion resistance is provided on the surface opposite to the surface on which the primer paint having heat ray reflective ultraviolet ray absorbing ability of the present invention is applied.
Those coated with a film having one or more functionalities can also be used.

In order to form a coating film of a primer paint having heat ray reflection ultraviolet ray absorbing ability of the present invention on the transparent substrate,
The above primer paint is applied to a transparent substrate as a dry coating film.
10 to 10 μm, preferably 2 to 5 μm
Cure at 100-120 ° C. for 30-60 minutes. If the coating film has a thickness outside the above range, a coating film having good adhesion to the protective thin film of the colloidal silica-containing organopolysiloxane paint cannot be obtained. In addition, as a method of applying, the composition is applied by a well-known method such as spraying, dipping, flow, roll coating and the like.

As the colloidal silica-containing organopolysiloxane paint derived from the organotrialkoxysilane and colloidal silica of the present invention, a colloidal silica-containing organopolysiloxane paint used for the surface treatment of ordinary resin films and sheets is used. it can.

The organopolysiloxane coating containing colloidal silica has a solid content of 20 to 90 parts by weight of a hydrolyzate of the compound represented by the general formula (1) and 1 to 100 n.
m to 80 to 10 parts by weight of silica fine particles, and the silica fine particles are generally added as colloidal silica dispersed in water or an alcohol such as methanol, ethanol, isobutanol, diacetone alcohol, and the like. The total amount of the hydrolyzate of the compound of the general formula (1) and silica fine particles is adjusted to 15 to 20% by weight using alcohol, water or a water-miscible solvent.

R ⁵ (OR ⁶ ) ₃ (1) wherein R ⁵ and R ⁶ are an alkyl group having 1 to ⁶ carbon atoms,
An alkoxyalkyl group having 3 to 6 carbon atoms or 6 to 6 carbon atoms
9 represents an aryl group. )

Examples of the compound represented by the above general formula (1) include, for example, methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, methyltri (2-methoxyethoxy) silane, ethyltriethoxysilane, ethyltriethoxysilane. Methoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and the like can be given.

The hydrolysis of the organotrialkoxysilane is carried out, for example, by adding water to a lower alcohol solution of the organotrialkoxysilane in the presence of an acid catalyst. Examples of the lower alcohol include methanol, ethanol, isopropanol, and butanol.
In the hydrolysis, an aqueous dispersion of colloidal silica may be added together with an acid catalyst.

It is preferable that a curing catalyst containing a buffer is added to the colloidal silica-containing organopolysiloxane coating so that the final coating film has optimum abrasion resistance. Examples of the curing catalyst include carboxylate salts such as dimethylamine acetate, ethanolamine acetate, dimethylaniline formate, benzoic acid, tetraethylammonium salt, sodium acetate, sodium propionate, sodium formate, and benzodiyltrimethylammonium acetate. I can do it. The curing catalyst is used in an amount of 0.1 to 2.0 parts by weight based on the solid content in the colloidal silica-containing organopolysiloxane paint.

As a method of applying the organopolysiloxane paint, for example, spraying, dipping, flow, roll coating, and the like can be used in the same manner as in the case of the primer paint composed of the thermosetting acrylic resin. The film thickness is preferably from 2 to 5 μm as a dry coating film. If it is thin, the surface protection effect is lost, and if it is thick, cracks can be easily found during heat curing. Further, the heat curing is preferably performed at 120 to 130 ° C. for about 1 hour.

Further, an injection molded article can be obtained by using the transparent body of the present invention. For example, a transparent body having heat ray reflection ultraviolet absorption performance is mounted in an injection mold so that the organopolysiloxane coating surface is on the mold side, and then the molten resin is injected into the mold. In addition, in one of the molds for injection molding, a transparent body having heat ray reflection ultraviolet absorption performance,
The other mold is coated with a transparent body coated with a film having one or more functions selected from anti-fogging, anti-static and scratch resistance. Then, a molded product can be obtained by flowing the molten resin into the mold between two films or sheets. The resin used for the injection molding is appropriately selected from the same resins as those for the transparent substrate used or those having a low heat distortion temperature.

[0027]

The present invention will be described in more detail with reference to the following examples. In the examples, “parts” are based on weight.

(Preparation of primer coating) In a 500 ml separable flask equipped with a Dimroth condenser, 40 parts of γ-methacryloxypropyltrimethoxysilane, 40 parts of methyl methacrylate, 5 parts of ethyl acrylate, 5 parts of vinyl acetate, 10 parts of glycidyl methacrylate, 10 parts of ethylene 0.2 part of glycol dimethacrylate, 0.5 part of azobisisobutylnitrile as a polymerization catalyst, 20 parts of diacetone alcohol as a solvent, and 80 parts of ethylene glycol monomethyl ether are charged and at 80 to 90 ° C. for 5 hours under a nitrogen stream. Stirred. The viscosity of the obtained thermosetting acrylic resin solution was 38,500 cst, and the content of alkoxysilyl groups in the copolymer was 40% by weight. Next, the obtained resin solution was adjusted with a mixed solvent in which the ratio of diacetone alcohol to ethylene glycol monomethyl ether was 20/80 so that the nonvolatile content became 10%. The viscosity of the primer coating obtained by this adjustment was 20 to 40 cst.

(Preparation of Colloidal Silica-Containing Organopolysiloxane Coating) In a 1-liter separable flask, 164 parts of methyltriethoxysilane and isobutanol 4 were added.
6 parts were charged, and kept at 5 ° C. or lower while stirring under ice cooling. 138 parts of colloidal silica (containing 20% of SiO ₂ ) dispersed in water adjusted to 5 ° C. or lower was added thereto, and the mixture was added under ice cooling. After stirring for 2 hours and further for 8 hours at 20 to 25 ° C, 45 parts of diacetone alcohol and 50 parts of isobutanol were added, and then a 10% aqueous solution of sodium propionate was added to the mixture.
Five parts were added and the pH was adjusted to 6 to 7 with acetic acid. Next, it was adjusted with isobutanol so that the nonvolatile content of the obtained paint became 17% by weight. The viscosity of the colloidal silica-containing organopolysiloxane coating obtained by this adjustment was about 5 cst, and the number average molecular weight of the nonvolatile component was about 1,000.

(Performance evaluation method) Measurement of solar radiation, visible light transmittance and reflectance: Shimadzu self-recording spectrophotometer (UV-3100PC)
(Type) according to JIS R3106. Weather resistance test: Exposure was performed using a sunshine carbon weather meter according to JIS K5400, and the appearance, yellowing degree, and adhesion after 3000 hours were examined.

Example 1 First, 13 parts by weight of 2,4-dihydroxybenzophenone as an ultraviolet absorber was added and dissolved in the primer coating obtained above with respect to 100 parts by weight of the solid content in the thermosetting acrylic coating. Non-leafing type aluminum paste (manufactured by Silverline, trade name: SS-6246AR,
A polycarbonate sheet (Mitsubishi Engineering Co., Ltd.) was prepared by adding and dispersing 5, 30, and 50 parts by weight of an average thickness of 0.2 μm, an average diameter of 16.0 μm, a hue of silver, and an aluminum powder amount of 64% by weight based on the solid content of the paint. Plastics Co., Ltd., trade name: Iupilon sheet, thickness: 0.5 mm) is applied by a flow method so as to have a dry coating of 2 to 5 μm, and is cured at about 120 ° C. for about 30 minutes. On top of this, the colloidal silica-containing organopolysiloxane paint obtained above was used as a dry coating film in an amount of 2 to 5 μm.
m, and cured at about 120 ° C. for about 1.0 hour.

The sheet thus obtained was measured for solar radiation, visible light transmittance and reflectance. Table 1 shows the results.

[0033]

[Table 1] Transmittance Reflectance (%) (%) Aluminum paste Solar radiation Visible light Solar radiation Visible light addition amount ───────────────────────── {5 parts by weight 70 72 20 20 30 parts by weight 30 31 50 50 50 parts by weight 20 21 60 60} ──────────

Further, as a result of measuring the surface hardness and weather resistance of the obtained sheet, the haze value (ΔH) after the Taber abrasion test was about 3 to 4% regardless of the amount of the aluminum paste added. Excellent in scratch resistance and weather resistance in 3000 hours with good appearance and good adhesion, yellowing degree (ΔY
I) was 5 and excellent durability.

Example 2 A non-leafing type aluminum paste (manufactured by Silver Line Co., Ltd.) obtained by chemically adhering a green organic pigment to an aluminum piece to the primer coating material to which the ultraviolet absorbent used in Example 1 was added. , Trade name: LEPC-202
7, average thickness 0.7 μm, average diameter 17 μm, aluminum powder amount 54% by weight),
0,50 parts by weight of the dispersed coating liquid was applied to a polycarbonate sheet by a flow method so as to have a dry coating film thickness of 2 to 5 μm, and was cured at about 120 ° C. for about 30 minutes. The used colloidal silica-containing polyorganosiloxane paint was applied and cured at about 120 ° C. for about 1.0 hour. The solar radiation, visible light transmittance and reflectance of the obtained sheet were measured. Table 2 shows the results.

[0036]

[Table 2] Transmittance Reflectance (%) (%) Aluminum paste Solar radiation Visible light Solar radiation Visible light addition ───────────────────────── {5 parts by weight 70 72 16 16 30 parts by weight 56 57 30 30 50 parts by weight 20 20 40 40} ──────────

In addition, as a result of measuring the surface hardness and weather resistance of the obtained sheet, the haze value (ΔH) after the Taber abrasion test was about 3 regardless of the amount of the aluminum paste added. ４4%, excellent in scratch resistance and excellent in weather resistance in 3000 hours. Both appearance and adhesion were good, and yellowing degree (ΔYI) was 4, and excellent durability was obtained.

Comparative Example 1 and Example 3 A spherical aluminum powder having an average particle diameter of 6 μm and a flaky aluminum powder having an average diameter of 6 μm and an average thickness of 0.1 μm were mixed with the solid content in the primer coating by 5, 30, The solar radiation, visible light transmittance and reflectance when a sample was prepared by adding 50% and using the same method as in Example 1 were measured. Table 3 shows the measurement results.
Shown in

[0039]

[Table 3] Shape Addition amount Transmittance Reflectivity (% / NVM) (%) (%) Solar visible light Solar visible light ───────────────────── {5 84 85 9 9 spherical 30 78 79 11 11 50 72 72 13 13 13} {5 70 70 23 23 Scaly 30 25 25 55 55 50 16 16 65 65} ────────────────

Example 4 A sample prepared in the same manner as in Example 1 except that the average diameter of the flaky aluminum powder having an average thickness of 0.2 μm was changed to 20 to 40 μm, the solar radiation, the visible light transmittance and the reflection. The rate was measured. Table 4 shows the measurement results.

[0041]

[Table 4] Average diameter Added amount Transmittance Reflectivity (%) (%) (μm) (% / NVM) Visible light solar light Visible light solar light {5 75 75 16 17 40 40 64 64 63 24 24 25 50 51 51 31 32} {5 74 74 22 22 23 30 30 56 56 56 37 38 50 43 42 45 45 45} {5 72 72 24 24 25 30 50 50 49 44 44 44 50 34 34 52 52} {5 71 70 23 23 20 30 30 31 50 50 50 28 28 54 54} ───────────────

[0042]

According to the present invention, heat rays are reflected and ultraviolet rays are blocked, and the adhesiveness, scratch resistance or durability is excellent.
It is possible to easily and inexpensively provide a transparent body and a molded product having an effective heat ray reflecting ultraviolet ray absorbing ability which can be widely used in various fields such as a building, a house, and a vehicle.

Claims (3)

[Claims] A heat ray characterized in that an ultraviolet absorber and scaly aluminum powder having an average thickness of 0.05 to 2.0 μm and an average diameter of 5 to 55 μm are added and dispersed in a primer coating composed of a thermosetting acrylic resin. Primer paint with reflective UV absorption performance. 2. A transparent body having heat-ray-reflecting / ultraviolet-ray-absorbing performance, characterized in that the primer coating of claim 1 is applied as a dry coating on one surface of a transparent substrate to a thickness of 1 to 10 μm and cured by heating. 3. The primer coating composition of claim 1 is applied as a dry coating on one surface of a transparent substrate to a thickness of 1 to 10 μm and cured by heating. Then, an organotrialkoxysilane, colloidal silica and a solvent are coated on the coating. Applying a colloidal silica-containing organopolysiloxane paint consisting of
A transparent body having heat-ray-reflecting / ultraviolet-absorbing performance, wherein the transparent body is successively coated by heating and curing to form a protective thin film.