JPH11333978A - Light permiable heat barrier sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight light permeable heat barrier sheet having light permeability, heat barrier properties and durability. SOLUTION: A light permeable heat barrier sheet 1 is constituted by laminating an aluminized film, which is obtained by providing an aluminum vapor deposition layer 3 with a thickness of 50-1,000 Åand a vapor deposition film protective layer 4 on the single surface of a polyester film 2, and a high density polyethylene flat yarn cloth 5 woven by using high density polyethylene flat yarns 7 as warp and weft yarns through an adhesive layer 9 formed by a sandwich lamination method using low density polyethylene and providing a low density polyethylene protective layer on the outer surface of the high density polyethylene flat yarn cloth 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-transmitting and heat-shielding sheet mainly transmitting visible light and reflecting infrared light.

[0002]

2. Description of the Related Art It is widely known that a synthetic resin film or woven fabric is provided with a metal-deposited layer of aluminum or the like and used as a heat-shielding sheet. However, if a metal evaporation layer with a sufficient thickness to shield solar energy is provided, the heat shielding property and the translucency are in an opposite relationship so that visible light is also blocked. When a sheet provided with a sheet is used for an agricultural house covering material or a simple tent sheet, the inside of the house or the tent is dark, which impairs workability, and is not satisfactory. In order to satisfy such a purpose, a transparent film is known as a light-transmitting and heat-shielding material in which a metal such as aluminum is deposited on the surface of the transparent film to such an extent that the transparency is not impaired and the infrared light is shielded. Have been. When actually using such a deposited film, not only the main purpose of the light-transmitting and heat-shielding properties,
Practical performance such as mechanical strength and weather resistance is required, and it is necessary to provide some kind of reinforcement without impairing the light-transmitting and heat-shielding properties.

[0003]

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to provide a light-transmitting and heat-shielding sheet having light-transmitting and heat-shielding properties, light weight and durability.

[0004]

According to the present invention, as a means for technically solving the above-mentioned problems, an aluminum vapor-deposited film having a 50-1000 mm thick aluminum vapor-deposited layer provided on one side of a light-transmitting film and a polyolefin cloth. The gist is a light-transmitting and heat-shielding sheet characterized by being laminated.

[0005] In the sheet having such a structure, the aluminum layer forms a layer having a uniform thickness of 50 ° or more, and reflects infrared rays efficiently. Further, a light-weight and durable sheet having the light-transmitting and heat-shielding functions of the present invention and having the reinforcing effect of the laminated polyolefin cloth can be obtained.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
As the translucent film used in the present invention, a film having excellent translucency such as a polyester film and a polyolefin film can be widely used. As the polyolefin film, a film composed of an ethylene / α-olefin copolymer produced by a metallocene catalyst which has a low molecular weight fraction and has excellent durability of a vapor-deposited layer is preferable.

The light-transmitting film has a thickness of 10 to 50.
μm is preferred. When the thickness is less than 10 μm, it is difficult to form a film having a uniform thickness.

[0008] An aluminum vapor-deposited film is formed by forming an aluminum vapor-deposited layer on one surface of the light-transmitting film by a known vapor deposition method. The thickness of the aluminum deposition layer is 50
Å1000Å, preferably 100〜500Å. In the range of the thickness of the above-mentioned aluminum vapor-deposited layer, a light-transmitting effect of 5 to 60% and a shielding effect of infrared rays of 95% or more can be obtained. If the thickness of the aluminum vapor-deposited layer is less than 50 °, the heat-shielding property is inferior, so that it is not preferable.

It is preferable to provide a vapor deposited film protective layer made of polyolefin on the aluminum vapor deposited layer. The vapor-deposited film protective layer may be formed by laminating a polyolefin layer by a known extrusion lamination method on an aluminum-deposited layer on which an anchor coating treatment has been performed. Polyethylene is preferable as the polyolefin used for the vapor-deposited film protective layer, and specifically, low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and the like are preferably used. Used.
The thickness of the protective layer is preferably from 10 to 30 μm.

The polyolefin cloth used in the present invention is a cloth formed by weaving and knitting a filament made of polyolefin. When the polyolefin cloth is laminated with an aluminum vapor-deposited film, it has a reinforcing effect on the aluminum vapor-deposited film. It is important that the light transmittance is not reduced. The woven structure of the woven or knitted fabric is not particularly limited, and a woven fabric such as a plain weave, a twill weave, and a woven weave, or a knitted fabric such as a warp knit or a weft knit can be used as appropriate.

The polyolefin used for the above-mentioned polyolefin cloth is not particularly limited as long as it can form a thread. Specifically, high-density polyethylene, medium-density polyethylene, and linear low-density polyethylene are used. Resins such as low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polypropylene, propylene-ethylene copolymer and the like may be used alone or in combination of two or more. The melt flow rate (hereinafter abbreviated as MFR) of the polyethylene is preferably 0.1 to 30 g / 10 min., And more preferably 1 to 10 g / 10 min.

The above-mentioned filamentous material is a flat yarn, a split yarn, a monofilament, a multifilament or the like made of polyolefin, all of which can be produced by a known production method. The fineness of the filament is 1
It is preferably from 00 to 2000 denier (hereinafter abbreviated as d), more preferably from 500 to 1500 d.

[0013] Cloths using these filaments include:
A densely woven cloth or a coarse mesh sheet can be appropriately selected within a range having a reinforcing effect without lowering the light transmittance. Among these, a flat yarn cloth or a mesh sheet made of multifilaments is preferable.Specifically, a cloth densely woven with flat yarn made of high-density polyethylene,
Alternatively, a mesh sheet in which multifilaments made of polypropylene are woven may be used.

The above-mentioned polyolefin cloth and the previously prepared aluminum vapor-deposited film are laminated. As a lamination method, lamination may be performed using an adhesive or the like, but an adhesive layer made of polyolefin is formed by a sandwich lamination method between a polyolefin cloth and a vapor-deposited film protective layer of an aluminum vapor-deposited film to form a laminate. Is preferred. Next, it is preferable to form a protective layer made of polyolefin outside the polyolefin cloth of the laminate. By forming this polyolefin protective layer,
It is possible to improve the antifouling property by imparting smoothness to the laminate and to improve the piercing strength of the laminate. Examples of a method for forming the protective layer made of the polyolefin include an extrusion lamination method and a dry lamination method, and the extrusion lamination method is preferable.

The thickness of the adhesive layer formed by the sandwich lamination method is preferably 20 to 60 μm. Also. The thickness of the polyolefin protective layer is 30 to 150 μm.
m is preferred. As the polyolefin used for the adhesive layer and the protective layer, polyethylene usually used for an extrusion lamination method is preferable. Specifically, low-density polyethylene, linear low-density polyethylene, ethylene-
A vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer and the like are preferably used.

In the present invention, the translucency depends on the thickness of the aluminum vapor deposition layer, but it is difficult to finish the thickness of the aluminum vapor deposition layer according to the set value.
In many cases, the transmittance measured in accordance with the above is a numerical value including a fraction. On the other hand, as an industrial product, there is a demand for a light-transmitting and heat-shielding sheet having a light transmittance such as 10%, 20%, 30%, 40%, and 50%. Therefore, by blending a pigment into the adhesive layer formed by sandwich lamination, the light transmittance can be finely adjusted to achieve a sharp numerical value as described above. The pigment used is preferably gray, brown, black, blue or the like, and the compounding amount is preferably in the range of 300 to 2500 ppm.

It is preferable that at least one side of the light-transmitting and heat-shielding sheet is coated with acrylic latex. The acrylic latex is an emulsion copolymer obtained by subjecting a vinyl monomer such as an alkyl (meth) acrylate, styrene, vinyl acetate, (meth) acrylic acid, and itaconic acid as a main component to emulsion polymerization according to a conventional method. No. As a method of coating the acrylic latex, known methods such as a dipping method, a roll coating method, a brushing method, and a spraying method can be used. However, since the handling is easy and a uniform coating layer can be formed, roll coating is used. The method is preferred. By coating with acrylic latex, even when a sheet used outdoors cracks due to flapping or storms, the acrylic coat layer prevents rainwater from entering and prevents corrosion of the aluminum vapor deposition layer. In particular, when sewing the sewing machine, water is prevented from entering through the needle hole of the sewing machine.

If necessary, an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, an antifogging agent may be used in the polyolefin used in the present invention as long as the characteristics of the present invention are not essentially impaired. Known additives such as an agent, a dispersant, a flame retardant, a nucleating agent, a foaming agent, and a crosslinking agent can be added.

[0019]

The present invention will be described in detail with reference to the following examples. The test method is as follows. 1 Tensile test: JISL1096 compliant 2 Tear test: JISL1096 compliant 3 Transmissivity: JISL1055 compliant

Example 1: A polyester film (2) made of polyester and having a thickness of 25 μm was selected as a light-transmitting film, a corona discharge treatment was applied to the surface thereof, and aluminum was vacuum-deposited to form an aluminum deposition layer (3) having a thickness of 350 °.
Was formed. After performing an anchor coating treatment on the surface of the aluminum vapor-deposited layer (3), low-density polyethylene (MFR = 12.0 g / 10 min., Density = 0.916)
(g / cm ³ , Tm = 105 ° C.) by extrusion lamination to form a 15 μm-thick coating to form a vapor-deposited film protective layer (4) to prepare an aluminum-deposited film.

On the other hand, high density polyethylene (MFR = 0.
7 g / 10 min., Density = 0.957 g / cm ³ , Tm
= 129 ° C.), cooled, slit and then stretched 5.2 times by a hot plate contact stretching method to obtain a high-density polyethylene flat yarn (7) with a fineness of 900 d (7). The 900d high-density polyethylene flat yarn (7) was plain-woven with a driving density of 9 × 9 yarns / inch as warp yarn to form a high-density polyethylene flat yarn cloth (5).

The high-density polyethylene flat yarn cloth (5) and the vapor-deposited film protective layer (4) of the aluminum vapor-deposited film prepared above were opposed to each other to obtain a low-density polyethylene (MFR = 12.0 g / 10 min., Density = 0.91
(6 g / cm ³ , Tm = 105 ° C.) by a sandwich extrusion lamination method to form an adhesive layer (9) having a thickness of 30 μm to form a laminate. Then, using the same low-density polyethylene, a low-density polyethylene protective layer (10) having a thickness of 40 μm was provided on the outside of the high-density polyethylene flat yarn cloth (5) of the laminate by an extrusion lamination method, and the basis weight was 172 g / m ^2. The light-transmitting and heat-shielding sheet (1) was obtained. The configuration is shown in FIG.

The resulting translucent heat-insulating sheet (1) has a tensile strength of 75 kgf / 5 cm, a tensile elongation of 26%, and a tear strength of 1
The weight was 0 kgf and the light transmittance was 30%. When this translucent heat-insulating sheet (1) was used for an agricultural house sheet, the illuminance in the outside air was 60,000 lux, the illuminance in the house was 18,000 lux, and it had translucency. The temperature inside the house was 21.5 ° C., and the heat shielding effect was good.

Example 2: Polypropylene (MFR = 20)
g / 10 min., density = 0.90 g / cm ³ , Tm = 1
(58 ° C.) to form a polypropylene multifilament (8) having a total fineness of 680 d / 120 f. A polypropylene multifilament mesh sheet (6) having an apparent driving density of 3 × 3 / inch with a woven weave composed of 680d × 2 as the warp and 1360d as the weft using the polypropylene multifilament (8) thus obtained is obtained. Was. The same operation as in Example 1 was performed except that the polypropylene multifilament mesh sheet (6) was used as the polyolefin cloth. A low-density polyethylene protective layer (10) having a thickness of 100 μm was provided on the outside of the polypropylene multifilament mesh sheet (6) of the laminate by an extrusion lamination method, and the basis weight was 23.
4 g / m ² of the translucent heat-shielding sheet (1) was obtained. The configuration is shown in FIG.

The resulting translucent heat-insulating sheet (1) has a tensile strength of 74 kgf / 5 cm, a tensile elongation of 23%, and a tear strength of 2
The weight was 8 kgf and the light transmittance was 30%. When this translucent heat-insulating sheet (1) was used for an agricultural house sheet, the illuminance in the outside air was 60,000 lux, the illuminance in the house was 18,000 lux, and it had translucency. The temperature inside the house was 22 ° C. and the heat shielding effect was good.

Example 3 A polyester film (2) made of polyester and having a thickness of 25 μm was selected as a translucent film, and the surface was subjected to corona discharge treatment to form a vacuum deposited aluminum layer (3) having a thickness of 350 °. As a result of the vapor deposition, an aluminum vapor-deposited layer (3) having a thickness of 325 ° was obtained. Since the light transmittance of this aluminum vapor-deposited layer (3) was predicted to be 32%, 800 ppm of a gray pigment was added to the adhesive layer (9) formed by the sandwich lamination method to increase the light transmittance by 30%. Was adjusted. Others were performed similarly to Example 1.

When this light-transmitting and heat-insulating sheet (1) was used for an agricultural house sheet, the illuminance in the house was 18,000 lux while the illuminance in the outside air was 60,000 lux, and the sheet had translucency.
When the outside air temperature was 25 ° C, the temperature inside the house was 22 ° C and the heat shielding effect was good.

[0028]

According to the present invention, a light-transmitting and heat-shielding property is imparted by providing an aluminum vapor-deposited layer having a thickness of 50 to 1000 ° on one side of a light-transmitting film for transmitting visible light and shielding infrared light, thereby providing a specific polyolefin cloth. By laminating, a sheet having practical strength, and being lightweight and flexible was obtained. This sheet is suitable for use as a roof material for temporary tents, a sheet for wall materials, an agricultural sheet, a garage house, a livestock barn, a poultry house, and the like.The inside is bright and has excellent workability. It is a light-transmitting and heat-shielding sheet having a cold protection effect. Further, when used as a partition sheet in a factory or the like, it is suitable as a shielding sheet having a shielding effect in which the inside can be seen from the inside due to the magic mirror effect but the inside cannot be seen from the outside.

[Brief description of the drawings]

FIG. 1 shows a light-transmissive heat-shielding sheet of Example 1.
(A) is a schematic sectional view, and (B) is a plan view of the used high-density polyethylene flat yarn cloth.

FIG. 2 shows a light-transmissive heat-shielding sheet of Example 2.
(A) is a schematic cross-sectional view, and (B) is a plan view of the used polypropylene multifilament mesh sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Translucent heat shielding sheet 2 Polyester film 3 Aluminum vapor deposition layer 4 Vapor deposition film protective layer 5 High density polyethylene flat yarn cloth 6 Polypropylene multifilament mesh sheet 7 High density polyethylene flat yarn 8 Polypropylene multifilament 9 Adhesive layer 10 Low density polyethylene protective layer

Claims (3)

[Claims] 1. A film having a thickness of 50 to 1 on one side of a translucent film.
A light-transmitting and heat-insulating sheet comprising a laminate of a polyolefin cloth and an aluminum vapor-deposited film having an aluminum vapor-deposited layer of 000 mm. 2. The light-transmitting and heat-shielding sheet according to claim 1, wherein the aluminum-deposited film and the polyolefin cloth are laminated by providing an adhesive layer by a sandwich lamination method. 3. The light-transmitting and heat-shielding sheet according to claim 1, wherein the light-transmitting property is adjusted by adding a pigment to the adhesive layer.