JP3419416B2 - Heat ray shielding methacrylic resin composition - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a methacrylic resin composition useful as a glazing material having excellent daylighting, transparency and heat ray shielding properties. 2. Description of the Related Art In recent years, as a roofing material and a wall material of a house and a solarium, a roofing material of a carport and a roofing material of an arcade, a methacrylic resin plate capable of transmitting visible light and capable of transmitting light has been used. Is being used. An object irradiated with light, such as sunlight, transmits, absorbs or reflects the light. Some of the light absorbed by the object is converted into thermal energy, raising the temperature of the object. That is, of the sunlight that irradiates an object, light whose temperature is raised acts on the object as a heat ray. Therefore, when the sunlight passing through the methacrylic resin plate as described above is irradiated and absorbed by objects such as human skin, automobiles, various commodities, and furniture, the temperature of the objects unnecessarily rises. There is a problem of doing. In order to solve this problem, a methacrylic resin plate conventionally used as a glazing material has a transmittance in a visible light wavelength region (about 380 nm to 780 nm) (hereinafter referred to as a visible light transmittance). For example, at least 5% to ensure daylighting. At this time, the haze is suppressed to 10% or less so that the amount of diffused light in the amount of transmitted light is not increased, and the transparency is ensured. Attempts have been made to improve the heat-ray shielding properties by suppressing the transmittance at 340 to 1800 nm (hereinafter referred to as solar transmittance) 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 so that heat rays can be reflected while securing daylighting and transparency. Or
In producing a methacrylic resin plate, a pigment is dispersed and colored so as not to be 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 an increase in manufacturing cost cannot be avoided. was there. On the other hand, in the case of a colored plate in which a pigment is dispersed in a methacrylic resin plate, the ordinary pigment mainly absorbs light in the visible light region, and thus cannot sufficiently absorb light in the wavelength region acting as a heat ray. 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 transmittance is as high as about 60%. When a near-infrared absorbing dye is dispersed in a methacrylic resin plate, it is possible to improve the heat ray shielding property as compared with a case where a normal pigment having an absorption band mainly in a visible light region is dispersed. Although it is conceivable, in general, near-infrared absorbing dyes do not have sufficient heat resistance, so the dye is decomposed at the time of forming 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 the 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 production cost of the methacrylic resin plate increases. An object of the present invention is to solve the problems of the prior art as described above, so that methacrylic resin can be provided with a practically preferable light-collecting property, see-through property and heat-ray shielding property at low cost as a glazing material. The purpose is to do. Means for Solving the Problems The present inventors have proposed that a methacrylic resin containing carbon black having a specific particle size in a specific range in a specific range makes visible light of 5% or more practically preferable as a glazing material. The inventors have found that the transmittance, the haze of 10% or less, and the solar transmittance of 50% or less can be simultaneously satisfied, and have completed the present invention. That is, according to the present invention, 100 parts by weight of a methacrylic resin , having a particle size of 30 nm or less and an ISO 787/16
Carbon black having a coloring power of 100 or more according to 0.0
001 to 1 part by weight , according to JIS R 3106
Therefore, when the measured visible light transmittance is 5% or more, the solar radiation transmittance is
A heat ray shielding methacrylic resin composition having a haze of 50% or less and a haze of 10% or less . Hereinafter, the present invention will be described in detail. 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 light region. This is because the property can be improved. In this case, it is necessary to use carbon black having a particle size of 30 nm or less. This means that the particle size is 3
If the thickness exceeds 0 nm, the amount of diffuse transmission of light incident on the methacrylic resin composition increases, that is, the haze increases, the methacrylic resin composition becomes cloudy, and visibility is impaired. 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, per 100 parts by weight of the methacrylic resin. Department.
This is because the amount of carbon black used is methacrylic resin 1
If the amount is 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 if it exceeds 1 part by weight, the visible light transmittance becomes too small, for example, less than 5%, and the daylighting property is impaired. The carbon black has a coloring power of 1 according to ISO 787/16 from the viewpoint of haze reduction.
It is preferable to use ones of 00 or more. The methacrylic resin used in the present invention may be 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, (meth)
Ethyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, (meth)
(Meth) acrylates such as dimethylaminoethyl acrylate, ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate,
Examples include (meth) acrylic acid polyhydric alcohol esters such as trimethylolpropane tri (meth) acrylate, (meth) acrylic acid, (meth) acrylamide, maleic acid, acrylonitrile, styrene, α-methylstyrene, and the like. 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 and the like can be used. The heat ray shielding methacrylic resin composition of the present invention may contain a dye, a pigment, a release agent, an antistatic agent, an ultraviolet absorber, an antioxidant, a stabilizer, a modifier, etc., if necessary. Can be added. The heat ray shielding methacrylic resin composition of the present invention can be produced according to a known method. For example, the monomer should constitute a methacrylic resin may be polymerized by addition of carbon black, a methacrylic resin by heating melting can be prepared by uniformly kneading the addition of carbon black. As described above, the heat-shielding methacrylic resin composition of the present invention that can be produced can be produced from inexpensive materials, 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 formed into a methacrylic resin plate having a predetermined shape according to a known method. The heat-shielding methacrylic resin composition of the present invention contains carbon black which exhibits the same level of light absorption in the visible light region and near infrared region with respect to 100 parts by weight of the methacrylic resin. 0001 to 1 part by weight is added. Therefore, according to the composition of the present invention, it is possible to simultaneously realize the visible light transmittance and the high heat ray shielding property necessary for securing the daylighting property. In this case given to using a particle size 30 n m as carbon black. Therefore, the amount of diffuse transmitted light in the total transmitted light can be suppressed,
Transparency can be ensured. EXAMPLES The heat ray shielding methacrylic resin composition of the present invention will be specifically described below with reference to examples. Incidentally, Oite <br/> the examples, "parts" indicates "parts by weight". Examples 1 to 7 and Comparative Examples 1 to 5 Carbon black having the particle size and coloring power (ISO 787/16) shown in Table 1 was added to 100 parts of methacrylic resin in the amount shown in Table 1. 250 ° C. in this mixture kneader (laboratory-flop <br/> Rasutomiru ME, manufactured by Toyo Seisakusho), 60rp
and kneading for 10 minutes. The kneaded mixture was press-molded using a compression molding machine (manufactured by Shinto Metal Works) to obtain a methacrylic resin plate having a thickness shown in Table 1. In Example 4, in addition to carbon black, a dye (Diaresin Blue N,
0.0015 parts of Mitsubishi Chemical Industry Co., Ltd.) was also added.
As Comparative Examples 4 and 5, a commercially available dye-colored smoke-free methacrylic resin plate not using carbon black (Comparative Example 4; Como Glass 530K, manufactured by Kuraray Co., Ltd .: Comparative Example 5; Como Glass 550K, Kuraray Co., Ltd.) Manufactured). With respect to the methacrylic resin plates of the examples and the comparative examples, the transmittance [τv] and the transmittance [τe] of the visible light (wavelength 380 to 780 nm) and the solar radiation (wavelength 340 to 1800 nm) are spectroscopically measured according to JIS R 3106. It measured using the photometer (U-3410, Hitachi, Ltd.). Further, haze was also measured according to JIS K 7105. Table 1 shows the results. Also,
The relationship between the visible light transmittance [τv] and the solar transmittance [τe] is plotted in FIG. [Table 1] Example of carbon black Particle size Coloring power Addition plate thickness Visible light transmittance Sunlight transmittance Haze (nm) (parts) (mm) [τv] (%) [τe] (%) (%) 1 18 140 0.0059 3.10 12 2.4 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 22 126 0.0058 3.15 10.7 18.9 4.0 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 21.5 250 66 0.0058 3.12 14.6 21.7 15.3 340 88 0.0058 3.06 15.8 24.2 24.2 4 --- 3.00 18.5 56.6 05- − − 3.00 29.0 61.0 0 Note that the actual Examples and a trade name and manufacturing company name of carbon black used in Comparative Examples are shown in Table 2. [Table 2] Product name Manufacturing company name Examples 1-4 # 1000 Mitsubishi Kasei Kogyo Co., Ltd. 5 Special Black 6 Degussa 6 MA100 Mitsubishi Kasei Kogyo Co., Ltd. 7 Printex 80 Degussa Comparative Example 1 LB-101P Degussa 2 SP-100P Degussa 3 M-25 Mitsubishi Chemical Industry Co., Ltd. From FIG. 1, the methacrylic resin plates using carbon black (Examples 1 to 7 and Comparative Examples 1 to 3) and the methacrylic resin plates not using carbon black (Comparative Examples 4 and 5) show a visible light transmittance. [Τv] and solar transmittance [τe]
It can be seen that the characteristic is greatly different with respect to the relationship. That is, the methacrylic resin plate using carbon black (Examples 1 to 7 and Comparative Examples 1 to 3)
Τe = (2τv / 3) + (100/3) which is plotted below the straight line 1 represented by the following equation (1), but does not use carbon black. The resin plates (Comparative Examples 4 and 5) are plotted above line 1. The one plotted on the upper side of the straight line 1 indicates that even if the visible light transmittance [τv] is the same, the solar radiation transmittance [τe] is higher and the heat shielding property is inferior to that plotted on the lower side. ing. Therefore, it can be confirmed from FIG. 3 that the use of carbon black can improve the heat shielding property while ensuring practically sufficient lighting property. Further, from Table 1, it is found that Examples 1 to 7 using carbon black having a particle size of 30 nm or less,
Comparative Examples 1 to 3 Using Carbon Black Exceeding nm
It can be seen that the haze is significantly 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 to 3)
Indicates that the haze exceeds 10% and the transparency is insufficient. According to the present invention, the methacrylic resin composition can be provided at 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 THE DRAWINGS FIG. 1 is a diagram showing the relationship between visible light transmittance and solar transmittance in methacrylic resin plates of Examples and Comparative Examples.

Continuation of front page (56) References JP-A-64-81901 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 33/12 C08K 3/04 G02B 5/22

Claims (1)

(57) [Claims 1] 100 parts by weight of a methacrylic resin and a particle size of 3
Coloring power according to ISO787 / 16 which is 0 nm or less
Contains 0.0001 to 1 part by weight of carbon black of 100 or more , and was measured according to JIS R 3106.
Visible light transmittance is 5% or more and solar transmittance is 50% or less
A heat ray shielding methacrylic resin composition having a haze of 10% or less .