JPH06192552A - Polycarbonate resin composition and polycarbonate resin building material - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Visible light transmission while maintaining the original impact strength and other physical properties of the basic resin. To obtain a polycarbonate resin composition having improved infrared reflection characteristics and a building material obtained by molding the composition. A polycarbonate resin composition in which a specific amount of titanium oxide-coated mica fine particles having a specified particle diameter is added to 100 parts by weight of a polycarbonate resin, and a polycarbonate resin building material molded by this composition.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to infrared reflection for obtaining a polycarbonate molded article applicable as a building material such as a roof material or a light-transmitting wall material for outdoor structures such as arcades and carports. The present invention relates to a polycarbonate resin composition having characteristics and a polycarbonate resin building material formed from such a resin composition.

[0002]

2. Description of the Related Art At present, transparent or translucent plastic plate materials are widely used as roofing materials such as arcades and carports and light-transmitting wall materials. In these applications, not only mechanical strength but also various properties such as weather resistance and UV resistance, and in addition to visible light, a property of reducing infrared (heat ray) transmission while transmitting visible light as much as possible is required. This is because by reducing the transmission of heat rays in the summer, it is possible to reduce discomfort and at the same time reduce the power consumption for air conditioning. That is, radiation selective properties are desired for such applications.

As a general technique for selectively transmitting a wavelength in a specific region, a glass or transparent plastic plate is coated with an appropriate substance, and the transparent substance itself is mixed with an appropriate organic or inorganic substance. It is known to obtain desired optical characteristics. The former coating method has been widely adopted for a long time, but multilayer coating is necessary to obtain desired characteristics, and vacuum deposition is often used for forming these coating films.
Multilayer coating by vacuum deposition is expensive, and care must be taken during handling so as not to physically or chemically damage the coating film. Therefore, it is suitable for photography and optical technology, and it is difficult to apply it to building materials and the like widely used under severe outdoor conditions.

On the other hand, the latter is easy to obtain a reliable product because inorganic materials such as barium sulfate, calcium carbonate and quartz and organic materials such as certain polymer particles are mixed with the material itself, and there are particular problems in handling. It is also excellent with little deterioration over time. However, if the base material is transparent resin,
The physical properties of the additive may be remarkably deteriorated by the additive, and there are many restrictions on the properties and the amount of the additive compound. In particular,
If a colorant is added to obtain the above-described absorption or reflection characteristics of visible light transmitting infrared rays, the transmittance of visible light also decreases in proportion, and the intended purpose has not been obtained.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and achieves the intended object with a simple structure and a polycarbonate resin composition and such a composition. It is an object to provide a building material formed of an object.

[0006]

[Means for Solving the Problems] This problem is that the particle diameter is 1 to 100 μm with respect to 100 parts by weight of a polycarbonate resin.
A polycarbonate resin composition in which 0.01 to 3 parts by weight of an object in which 20 to 60% by weight of titanium oxide is coated on the surface of mica particles of m is added, and a plate-like body formed from such a composition. Solved by wood. Further, an ultraviolet absorber can be added.

[0007]

The building material molded from the polycarbonate resin composition having infrared reflecting properties according to the present invention is a mica fine particle coated with titanium oxide in a predetermined weight% as described above. It is melt-kneaded by adding 0.01 to 3 parts by weight of a compound having a specific particle size. With such a resin-molded plate, the incident light flux is scattered by the dispersed mica fine particles with selectivity depending on the wavelength, and a large amount of infrared light is reflected. In this case, there is little reflection in the visible light region, and the transmittance is not reduced so much.

A molded plate made of a polycarbonate resin composition having such characteristics can be used as a building material such as a roofing material or a wall material, and allows visible light to pass therethrough with a high transmittance to radiate infrared rays. Many components are reflected. As a result, for example, when it is applied to the use as an arcade roofing material, a large amount of visible light components are transmitted therethrough, and thus it is possible to positively use natural daylighting, and thus to save power for lighting in the daytime. On the other hand, since the transmission in the infrared region is reduced, the temperature rise under the roof in the summer can be suppressed, and the air conditioning power can be reduced. In addition, the reflection effect in the infrared region can be expected to the irradiation from the inside as well, and the effect of reflecting the infrared irradiation from the inside in winter and not escaping to the outside can be expected. Furthermore, if an ultraviolet absorber is added, it is possible to reduce the ultraviolet region in addition to the above-mentioned reduction of the infrared region.

[0009]

EXAMPLES The contents of the present invention will be disclosed below with reference to examples. In the examples, a polycarbonate resin was used as the basic transparent resin. Polycarbonate resin is a transparent, chemically and physically stable resin, and is known as one of so-called engineering plastics. In this example, Lexan 141 (trade name: manufactured by Nippon GE Plastics Co., Ltd.) was used.

EXAMPLE In preparation of the resin composition according to the present invention, mica fine particles having a particle size of 5 to 50 μm and a titanium oxide coating rate of 40% relative to 100 parts by weight of the above-mentioned polycarbonate resin 0 .05 parts by weight were sufficiently mixed, and further melt-kneaded by an extruder to prepare pellets.

The titanium oxide-coated mica fine particles and the polycarbonate resin can be mixed by a known mixing device such as a ribbon blender, a Henschel mixer, a Banbury mixer, or a kneader. In addition, the extrusion may be performed under normal extrusion conditions of the base resin. In this example, according to the extrusion conditions of the polycarbonate resin, extrusion was performed with a uniaxial extruder at an extrusion temperature of 270 ° C. and a screw rotation speed of 127 rpm to produce pellets.

With the pellets thus obtained,
A test plate having a thickness of 3 mm was molded and the optical characteristics were measured. A graph showing the measurement result is as shown in FIG. In this graph, the horizontal axis represents wavelength (nm) and the vertical axis represents transmittance (percent T). For the measurement, a self-recording spectrophotometer (transmittance measuring instrument) U-4000 manufactured by Hitachi, Ltd. was used. The measurement conditions are
Scan speed: 300 (750) nm / min, slit (visible): 6.0 nm, slit (near infrared): automatic control. Also, Photomal voltage: Automatic control, PbS
Sensitivity: set to 2.

As is clear from the graph showing the measurement results, the visible light of 700 nm or less maintains a high transmittance of about 70%.

When the amount of the mica fine particles coated with titanium oxide is 0.02 parts by weight or less, the reflection effect in the infrared light region becomes insufficient, and when it is 1.0 parts by weight or more, the visible light region is transmitted. This is because the rate also decreases. It should be noted that it is optional to add other additives such as various stabilizers, flame retardants, colorants, etc. within a range that does not impair the object of the present invention.

Comparative Example A test plate was prepared by molding a resin composition for building materials by adding a pigment which has been conventionally used for this kind of application. In this comparative example, 0.6 part by weight of carbon black and 0.4 part by weight of anthraquinone-based blue organic pigment were added to 100 parts by weight of the same resin as the polycarbonate resin in the example, and the pellets were extruded in the same manner as in the example. Was manufactured. Using this pellet, a test plate having a thickness of 3 mm was formed.

The optical characteristic curve obtained by measuring the thus-formed test plate in the same manner as in the example is as shown in FIG. From this curve, when the total light transmittance in the visible light region is set to the same level as that of the test piece plate of the example, 900
It can be seen that the transmission in the infrared light region higher than about 1000 nm is significantly increased to 15 to 18% on average and 20% or more at maximum.

[0017]

Industrial Applicability According to the present invention, the building material molded from the resin composition having the infrared ray reflection property has excellent durability and high transmittance for wavelengths in the visible light region. However, it has the effect of reducing the transmittance in the infrared region. Further, by appropriately adding an ultraviolet absorber, it is possible to simultaneously reduce ultraviolet rays in addition to the infrared region. Therefore, this material is cheaper than conventional products, is easy to mold, and exhibits high economic efficiency. Further, it has good moldability, can be molded into any shape, and is suitable for mass production of building materials such as roofing materials and translucent wall materials, which often have a large area.

[Brief description of drawings]

FIG. 1 is a percentage spectral reflectance characteristic curve of a test plate molded from the polycarbonate resin composition according to the present invention.

FIG. 2 is a percentage spectral reflection characteristic curve of a test plate molded from the resin composition for building materials according to the prior art.

Claims (2)

[Claims] 1. An object in which 20 to 60% by weight of titanium oxide is coated on the surface of mica particles having a particle diameter of 1 to 100 μm per 100 parts by weight of a polycarbonate resin is 0.0.
A polycarbonate resin composition, wherein 1 to 3 parts by weight is added. 2. An object obtained by coating 20 to 60% by weight of titanium oxide on the surface of mica particles having a particle size of 1 to 100 μm per 100 parts by weight of a polycarbonate resin is used.
A polycarbonate resin building material, wherein the polycarbonate resin building material is a plate-shaped body formed from a composition containing 1 to 3 parts by weight.