JPH0762189A - Heat-ray-intercepting methacrylic resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. which is suitable as a glazing material excellent in natural lighting, see-through, and heat-ray-intercepting capability by compounding a methacrylic resin with a specified small amt. of a carbon black having a specified small particle size. CONSTITUTION:The compsn. is prepd. by compounding 100 pts.wt. methacrylic resin with 0.0001-1 pt.wt. carbon black having a particle size of 30nm or lower. Since the carbon black absorbs as much light in the near-infrared range as light in the visible range, the heat-ray-intercepting capability of the compsn. can be improved even when the visible ray transmittance is adjusted near that of a compsn. contg. a generally used pigment, satisfying both a haze of 10% or lower and a solar-radiation transmittance of 50% or lower.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a methacrylic resin composition useful as a glazing material having excellent lighting properties, transparency and heat ray shielding properties.

[0002]

2. Description of the Related Art In recent years, a methacrylic resin plate capable of transmitting visible light and seeing through has been used as a roofing material and wall material for houses and solariums, a carport roofing material and an arcade roofing material. It is like this.

By the way, an object irradiated with light such as sun rays transmits, absorbs or reflects the light. Part of the light absorbed by an object is converted into heat energy, which raises the temperature of the object. That is, of the sunlight that irradiates the object, the light that raises the temperature of the object acts as a heat ray on the object.

Therefore, when the sunlight passing through the methacrylic resin plate as described above is applied to and absorbed by the skin of the human body, automobiles, various products, furniture and the like, the temperature of the object unnecessarily rises. There is a problem of doing.

In order to solve this problem, conventionally, a methacrylic resin plate used as a glazing material has a transmittance in the visible light wavelength region (about 380 nm to 780 nm) (hereinafter referred to as visible light transmittance). For example, at least 5% to secure the daylighting property, and at that time, haze is suppressed to 10% or less so as to prevent the increase of the diffused light amount in the transmitted light amount to ensure the transparency, and the entire wavelength range of the sunlight ( It has been attempted to improve the heat ray shielding property by suppressing the transmittance (hereinafter, referred to as solar radiation transmittance) at 340 to 1800 nm) to about 50% or less.

For example, a thin film of aluminum or silver is formed on the surface of a methacrylic resin plate by a vapor deposition method, and the methacrylic resin plate itself is used as a half mirror, which enables heat rays to be reflected while ensuring light-collecting properties and transparency. Or
At the time of producing a methacrylic resin plate, pigments are dispersed and colored to the extent that it does not become opaque, or a near-infrared absorbing dye is contained in the methacrylic resin plate.

[0007]

However, when a thin film of aluminum or silver is formed on a methacrylic resin plate, a high vacuum environment must be created, and there is a problem that an increase in manufacturing cost cannot be avoided. .

Further, in the case of a colored plate in which a pigment is dispersed in a methacrylic resin plate, ordinary pigments mainly absorb light in the visible light region, and thus cannot sufficiently absorb light in the wavelength region acting as heat rays. As a result, there is a problem that the heat ray shielding property of the methacrylic resin plate cannot be sufficiently improved. For example, in the case of an ordinary colored plate, even if the visible light transmittance is 20 to 30%, the solar radiation transmittance is as high as about 60%.

When the near-infrared absorbing dye is dispersed in the methacrylic resin plate, it is possible to improve the heat ray shielding property as compared with the case of dispersing an ordinary pigment having an absorption band mainly in the visible light region. Although it is considered, near-infrared absorbing dyes generally do not have sufficient heat resistance, so the dye decomposes during molding of the methacrylic resin plate, or when the methacrylic resin plate is manufactured by the cast polymerization method, a radical polymerization initiator is used. Due to the decomposition of the dye, the concentration of near-infrared absorbing dye in the methacrylic resin plate is insufficient,
As a result, there is a problem that the heat ray shielding property cannot be sufficiently improved. Further, since the near-infrared absorbing dye is expensive, there is a problem that the manufacturing cost of the methacrylic resin plate increases.

The present invention is intended to solve the above-described problems of the prior art, and to provide methacrylic resin with practically preferable lighting properties, transparency and heat ray shielding properties as a glazing material at low cost. The purpose is to do.

[0011]

Means for Solving the Problems The present inventors have made a methacrylic resin contain carbon black having a specific particle diameter in a specific range to obtain a visible light transmittance of 5% or more which is practically preferable as a glazing material. It was found that a haze of 10% or less and a solar radiation transmittance of 50% or less can be simultaneously satisfied, and the present invention has been completed.

That is, according to the present invention, 100 parts by weight of methacrylic resin and 0.000 of carbon black having a particle size of 30 nm or less are used.
A heat ray-shielding methacrylic resin composition, characterized by containing 1 to 1 part by weight.

The present invention will be described in detail below.

The methacrylic resin composition of the present invention is characterized by containing carbon black. This is because carbon black absorbs light in the near-infrared region to the same extent as light in the visible region, so compared to the case where ordinary pigments are added, even if the visible light transmittance is similar, heat rays This is because the shielding property can be improved. In this case, the carbon black has a particle size of 30 nm.
You need to use: This is because when the particle size exceeds 30 nm, the diffuse transmitted light amount out of the total transmitted light amount of the light incident on the methacrylic resin composition increases, that is, the haze increases, and the methacrylic resin composition becomes cloudy and the transparency is low. This is because it is hindered.

The amount of carbon black used is 0.0001 to 1 part by weight, preferably 0.0002 to 0.5 part by weight, more preferably 0.0002 to 0.2 part by weight, based on 100 parts by weight of the methacrylic resin. Be a part.
This is because the amount of carbon black used is methacrylic resin 1
If less than 0.0001 parts by weight with respect to 00 parts by weight,
This is because the heat ray-shielding property is insufficient, and when it exceeds 1 part by weight, the visible light transmittance becomes too small, for example, less than 5%, which impairs the daylighting property.

Further, as carbon black, from the viewpoint of haze reduction, the coloring power according to ISO787 / 16 is 1
It is preferable to use those of 00 or more.

The methacrylic resin used in the present invention is a homopolymer of methyl methacrylate or 50% by weight or more of a methyl methacrylate monomer, and 50% by weight or less of another monomer copolymerizable with the methyl methacrylate monomer. Can be used.

Other monomers copolymerizable with the methyl methacrylate monomer include methyl acrylate and (meth)
Ethyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, (meth)
(Meth) acrylic acid esters such as dimethylaminoethyl acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate,
(Meth) acrylic acid polyhydric alcohol esters such as trimethylolpropane tri (meth) acrylate, (meth) acrylic acid, (meth) acrylamide, maleic acid, acrylonitrile, styrene, and α-methylstyrene can be exemplified. These may be used in combination of two or more.

As the methacrylic resin used in the present invention, those produced by a usual casting polymerization method, suspension polymerization method, emulsion polymerization method, solution polymerization method or the like can be used.

The heat ray-shielding methacrylic resin composition of the present invention may contain dyes, pigments, mold release agents, antistatic agents, ultraviolet absorbers, antioxidants, stabilizers, modifiers, etc., if necessary. Various additives can be added.

The heat ray-shielding methacrylic resin composition of the present invention can be manufactured by a known method. For example, carbon black may be added to the monomer to form the methacrylic resin and polymerized, or the methacrylic resin can be produced by heating and melting the methacrylic resin, adding the carbon black and uniformly kneading.

As described above, the heat-shielding methacrylic resin composition of the present invention that can be produced can be produced from an inexpensive material, and the production method is simple. Therefore, it can be manufactured at low cost. Further, the heat-shielding methacrylic resin composition of the present invention can be molded into a methacrylic resin plate having a predetermined shape by a known method.

[0023]

In the heat ray-shielding methacrylic resin composition of the present invention, 0.0001 to 1 of carbon black which exhibits the same degree of light absorption in the visible light region and the near infrared region is added to 100 parts by weight of the methacrylic resin. Add in parts by weight. Therefore, according to the composition of the present invention, it becomes possible to simultaneously realize the visible light transmittance and the high heat ray shielding property which are necessary to secure the daylighting property. In this case, carbon black having a particle size of 30 μm or less is used. Therefore,
The amount of diffuse transmitted light in the total transmitted light can be suppressed, and the transparency can be secured.

[0024]

EXAMPLES Hereinafter, the heat ray-shielding methacrylic resin composition of the present invention will be specifically described with reference to Examples. In the examples, "part" means "part by weight".

Examples 1 to 7 and Comparative Examples 1 to 5 Carbon black having a particle size and a coloring power (ISO787 / 16) shown in Table 1 was added to 100 parts of methacrylic resin at the addition amount shown in Table 1, This mixture is kneader (Laborast Mill ME, manufactured by Toyo Seisakusho) at 250 ° C. and 60 rp.
The mixture was kneaded under the condition of 10 minutes. The kneaded mixture was press-molded using a compression molding machine (manufactured by Shindo Metal Co., Ltd.) to obtain a methacrylic resin plate having a thickness shown in Table 1.

In addition, in Example 4, in addition to carbon black, a dye (Diaresin Blue N,
0.0015 parts was also added.
Further, as Comparative Examples 4 and 5, a commercially available smoke-colored methacrylic resin plate of a dye coloring type that does not use carbon black (Comparative Example 4; Comograss 530K, manufactured by Kuraray Co., Ltd .: Comparative Example 5; Comograss 550K, Kuraray Co., Ltd.). Manufactured) was used.

With respect to the methacrylic resin plates of Examples and Comparative Examples, according to JIS R 3106, the visible light (wavelength 380 nm to 780 nm) transmittance [τv] and solar radiation (wavelength 340 to 1800 nm) transmittance [τe] were spectrally separated. It measured using the photometer (U-3410, Hitachi Ltd. make). The haze was also measured according to JIS K 7105. The results are shown in Table 1. Also,
The relationship between the visible light transmittance [τv] and the solar radiation transmittance [τe] is plotted in FIG. 1.

[0028]

[Table 1] Example of carbon black Particle size Coloring amount Addition amount Plate thickness Visible light transmittance Solar radiation haze (nm) (part) (mm) [τv] (%) [τe] (%) (%) 1 18 140 0.0059 3.10 12 .4 21.8 1.8 2 18 140 0.0035 3.12 28.1 37.4 1.6 3 18 140 0.1 0.22 9.3 19.7 1.8 4 18 140 0.0058 3.12 19.2 34.4 1.2 5 17 116 0.0058 3.06 15.1 24.8 1.5 6 22 22 126 0.0058 3.15 10.7 18.9 4.0 7.0 7 16 126 0.0058 3.12 10.7 18.7 3.1 Comparative example 1 95 27 0.0058 3.10 34 .2 34.9 21.5 2 50 66 0.0058 3.12 14.6 21.7 15.3 3 40 40 88 0.0058 3.06 15.8 24.2 24.2 4 − − − 3.00 18.5 56.6 05 − --3.00 29.0 61.00

Table 2 shows the trade names and manufacturer names of the carbon blacks used in the examples and comparative examples.

[0030]

[Table 2] Product name Manufacturer name Examples 1 to 4 # 1000 Mitsubishi Kasei Co., Ltd. 5 Special Black 6 Degussa 6 MA100 Mitsubishi Kasei 7 Printex 80 Degussa Comparative Example 1 LB-101P Degussa 2 SP-100P Degussa 3 M-25 Mitsubishi Kasei Co., Ltd. From FIG. 1, the methacrylic resin plate using carbon black (Examples 1 to 7 and Comparative Examples 1 to 3) and the methacrylic resin plate not using carbon black (Comparative Examples 4 and 5) have visible light transmittances. [Τv] and solar radiation transmittance [τe]
It can be seen that the characteristics greatly differ from the relationship with. That is, the methacrylic resin plates using carbon black (Examples 1 to 7 and Comparative Examples 1 to 3) are shown in FIG.
Formula (1)

[0031]

## EQU00001 ## .tau.e = (2.tau.v / 3) + (100/3) (1) Plotted below the straight line 1 represented by (1), but a methacrylic resin plate using no carbon black (Comparative Example 4 and 5) is plotted above line 1. The one plotted on the upper side of the straight line 1 shows that the solar radiation transmittance [τe] is high and the heat shielding property is inferior compared to the one plotted on the lower side even though the visible light transmittance [τv] is the same. ing. Therefore, from the figure, it can be confirmed that by using carbon black, it is possible to improve the heat shielding property while ensuring practically sufficient lighting.

Further, from Table 1, Examples 1 to 7 using carbon black having a particle size of 30 nm or less, and a particle size of 30
Comparative Examples 1 to 3 using carbon black exceeding nm
You can see that haze is very different between and. That is, the methacrylic resin plate using carbon black having a particle size of more than 30 nm (Examples 1 to 7) has a haze of less than 5%, while the methacrylic resin plate using carbon black having a particle size of more than 30 nm ( Comparative Examples 1-3)
Shows that the haze exceeds 10% and the transparency is insufficient.

[0033]

EFFECTS OF THE INVENTION According to the present invention, the methacrylic resin composition can be provided at a low cost with a light-collecting property, a see-through property and a heat ray shielding property suitable as a glazing material.

[Brief description of drawings]

FIG. 1 is a relationship diagram between visible light transmittance and solar radiation transmittance in methacrylic resin plates of Examples and Comparative Examples.

Claims (2)

[Claims] 1. A methacrylic resin of 100 parts by weight and a particle size of 30.
A heat ray-shielding methacrylic resin composition containing 0.0001 to 1 part by weight of carbon black having a size of not more than nm. 2. Carbon black ISO 787/16
The heat ray-shielding methacrylic resin composition according to claim 1, which has a coloring power of 100 or more.