JPH03216985A - Far infrared ray emanating material - Google Patents

Abstract

PURPOSE:To obtain excellent flexibility and prevent the peeling of an Al2O3 layer by weaving the strands formed with alumina films having a specific thickness by the anode oxidation processing on peripheries of wire rods made of aluminum or aluminum alloy having a specific wire diameter into a fabric shape. CONSTITUTION:Strands 2 formed with alumina films (Al2O3 films) 4 having the thickness 5mum or larger by the anode oxidation processing on peripheries of wire rods 3 made of Al or Al alloy with the wire diameter 0.2mm or smaller are woven to constitute a far infrared ray emanating material 1. This far infrared ray emanating material 1 has excellent adhesion between the Al2O3 layers 4 and the wire rods 3 made of Al or Al alloy. The Al2O3 layers 4 are not peeled when the heat cycle of quick heating or quick cooling is repeatedly applied. The far infrared ray emanating material 1 has excellent flexibility, it can be bent into a complex shape, the bent portion is flexibly deformed, and the Al2O3 layers 4 on the peripheries of the wire rods 3 made of Al or Al alloy are prevented from generating cracks and being peeled off when mechanical deformation is applied.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a far-infrared radiating material that emits far-infrared rays using the heat of a heating element, and particularly relates to a far-infrared radiating material with improved peeling resistance and flexibility. Regarding infrared emitting materials.

[Prior Art] In recent years, there has been an increasing demand for far-infrared heaters that heat objects by emitting far-infrared rays. Generally, in this type of heater, a far-infrared radiation material is provided around a heating element, and the far-infrared radiation material is heated by the heat of the heating element to emit far-infrared rays. This far-infrared emitting material is made by coating the surface of a metal or ceramic base material with ceramic powder with high far-infrared emissivity by coating, spraying, thermal spraying, or other methods to form a ceramic layer on the surface of the base material. It is something. The material for this ceramic layer is alumina (A720), which has a particularly high far-infrared emissivity.
3) is preferable, A! Far-infrared emitting materials coated with 203 layers are mainly used.

Conventionally, A! has been coated on a substrate by painting or spraying. The 203 layer has a drawback in that it easily peels off from the base material during thermal cycles of rapid heating and rapid cooling due to the difference in thermal expansion coefficient between the layer and the base material. For this reason, far-infrared radiating materials are used that have improved peeling resistance by blending inorganic binders such as clay or various materials with AIzos.

However, in this case, the excellent far-infrared emissivity of AIzoa is degraded by the addition of an inorganic binder, and even if such a binder is added, the effect of improving peel resistance is insufficient.

Therefore, in order to avoid such inconveniences due to peeling of the far-infrared radiating material, the far-infrared radiating material in the desired shape is molded only from ceramic materials with excellent far-infrared radiating properties, and a heating element is placed inside the radiating material. There is a heater equipped with

In addition, a plate-shaped or tape-shaped AI base material can be anodized to achieve 8! A far-infrared radiating material has been proposed in which an AjzOa layer is firmly formed on the surface of a base material.

[Problems to be Solved by the Invention] However, when a far-infrared radiating material with a desired shape is formed from the ceramic material itself, it is difficult to obtain a radiating material with a complicated shape, and it is difficult to resist mechanical shock. The problem is that it is brittle.

In addition, AtzO is applied on the surface of a plate-shaped or tape-shaped Al base material.
In the case of a far-infrared emitting material formed with three layers, the AI'zgos layer is in close contact with the A-substrate in the case of relatively gentle deformation, but when subjected to severe processing such as bending at right angles, the surface layer Cracks occurred in the A1203 layer of
There is a problem that the At20n layer gradually peels off from this portion.

The present invention has been made in view of such problems, and includes:
The object of the present invention is to provide a far-infrared radiating material that has excellent visibility and can prevent peeling of the A7203 layer.

[Means for Solving the Problems] The far-infrared emitting material according to the present invention has a wire rod made of aluminum or an aluminum alloy with a wire diameter of 0.2 mm or less, and the peripheral surface of the wire rod is anodized to have a thickness of 5 μm or more. It is characterized by being constructed by weaving wires coated with alumina into a cloth.

[Function] In the present invention, the wire diameter is reduced to 0.2 by anodizing treatment.
A below item! Alternatively, a far-infrared radiating material is constructed by weaving wires made of an AI alloy wire with an alumina coating (A7203 layer) formed on the peripheral surface into a cloth shape. This A layer 20a is Af or A! Because of its excellent adhesion to the alloy, even when subjected to repeated thermal cycles of rapid heating and cooling, A! Or A! It will not peel off from the wire made of alloy. Further, the far-infrared ray emitting material according to the present invention is constructed by weaving the above-mentioned wires into a cloth shape. In this way, even when a woven fabric using thin wire is bent into a complicated shape, the folded part deforms flexibly, which prevents the AjzC)t layer from peeling off from the wire due to mechanical deformation. Ru.

Therefore, A! The far infrared ray emitting material can be easily deformed to cover the heating element without causing peeling of the z03 layer.

Next, A7 or A! The reason for limiting the wire diameter of the alloy wire and the thickness of the Alz03 layer will be explained.

! ! No no 8! Or, if the wire diameter of the A1 alloy wire exceeds 0.2L, even if a woven fabric of far infrared radiation material is manufactured by weaving a wire with an Alg03 layer formed on the circumference of the wire, the woven fabric The flexibility is insufficient, and the far-infrared radiating material cannot be flexibly deformed to correspond to the shape of the heating element. Furthermore, in this case, cracks may occur in the surface layer of the A1203 layer formed on the circumferential surface of the wire. Therefore, AI or A
The wire diameter of the I alloy wire is limited to 0.2 mm or less.

If the thickness of the alumina coating 1lX (A No. 03 layer) of No. 1 is less than 5 μm, the portion occupied by AI 2 0 3 will be small and excellent far-infrared radiation cannot be obtained, so it cannot be used as a far-infrared radiating material. Not suitable. Therefore, the thickness of the Ar20+ layer (alumina coating) is limited to 5 μm or more.

[Embodiments] Next, embodiments of the present invention will be described with reference to the accompanying drawings.

The construction drawing (a) is a far-infrared radiation material 1 according to an embodiment of the present invention.
FIG. 1(b) is a cross-sectional view showing the strands 2 constituting the far-infrared radiation material 1 of this embodiment.

Bare wire 2 is A! Or A! AI203 on the peripheral surface of the alloy wire 3
It is constructed by covering layer 4. This wire 3 has a wire diameter of 0.2 mm or less, and the AI203 layer 4 has a thickness of 5 mm by oxidizing the surface layer of the wire 3 by anodizing.
It is formed to have a thickness of μm or more. The far-infrared radiation material 1 of this embodiment is constructed by weaving the above-described wires 2 in a cloth-like manner by crossing them alternately.

The far-infrared radiation material 1 configured in this way is A! or A
! Since the wire 3 made of alloy is a thin wire with a wire diameter of 0.2 mm or less, it has excellent flexibility, so that it can be arbitrarily deformed to match the shape of the heating element to cover the heating element. For example, when covering a prismatic heating element, as shown in FIG. , it is possible to cover the prismatic heating element. In this case, since the far-infrared radiating material is configured in the form of a woven fabric, the bent portion is flexibly deformed. Therefore, due to such mechanical deformation, the AI2Oa layer 4 changes to A! Or A! It will not peel off from the wire rod 3 made of the alloy.

In addition, when the far infrared radiation material is heated by a heating element, A1
Far infrared rays are emitted from the zO* layer 4.

This A7203 layer 4 is A! Or A! Since it is formed by oxidizing the surface of the wire 3 made of an alloy, it has excellent adhesion to the wire 3. Therefore, even if subjected to repeated thermal cycles of rapid heating or cooling, A! The 203 layer 4 does not peel off from the wire 3.

Next, a far-infrared radiation material according to an example of the present invention is manufactured,
The results of comparing its performance with that of a far-infrared radiation material according to a comparative example will be explained.

A with a support wire diameter of 0.2! The wire was anodized and a 20 μm thick AJ203 layer was formed on its surface.

This strand was woven into a 1 m square cloth to produce a woven fabric of far-infrared radiation material.

An A-Si alloy (1% by weight Si, balance Aj) wire with a wire diameter of 50 μm was anodized and its surface was coated with a thickness of 5 μm.
An Ata 03 layer was formed. This strand was woven into a tm square cloth to produce a woven fabric of far-infrared radiation material.

Example 1 except that the wire diameter of the Al wire was 0.3 mm.
A woven fabric of far-infrared radiation material was produced in the same manner as above.

A woven fabric of far-infrared radiation material was produced in the same manner as in Example 2, except that the thickness of the A1203 layer was 3 μm.

By anodizing an AI plate with a wall thickness of 0.5mm and a size of 1m square, and forming an A1a03 layer with a thickness of 20μm on its surface, far infrared rays can be emitted. Radiant material was manufactured.

A of 95% by weight of L Sage! A slurry made by adding water to a mixed powder of 203 powder and 5% by weight Kibushi clay powder and adjusting the viscosity to an appropriate level was sprayed onto a steel plate with a wall thickness of 0.5mm and a size of 1m square. It was dried to produce a far-infrared radiating material.

The far-infrared emissivity, fi, 1*03 layer peel resistance and processability of the far-infrared emitting materials according to Example 1.2 and Comparative Examples 1 to 4 described above were investigated.

In the measurement of far-infrared emissivity, the far-infrared radiating material was heated to 300° C., and the emissivity of infrared rays in the wavelength range of 4 to 20 μm was measured at 300° C. However, emissivity refers to the ratio of the radiant energy of a sample to the radiant energy of a black body (emissivity in all wavelength ranges!).

In addition, in testing the peeling resistance of radiation materials, far-infrared radiation materials at room temperature were heated for 25 minutes to raise the humidity to 500°C, held at this temperature for 5 minutes, and then cooled for 30 minutes to room temperature. A series of heat cycle tests were conducted in which the temperature was lowered to a barking state, and the peeling state of the Af203 layer was investigated.

Furthermore, in the workability test, as shown in Figure 2,
Prismatic mold (size: 25cm x 25cm x
The far-infrared radiating material was bent at right angles at four locations so as to cover the longitudinal side surfaces of the sample (100cm), and it was examined whether or not cracks would occur at the bent portions.

As a result, the far-infrared radiation materials according to Examples 1 and 2 both had excellent far-infrared emissivities of 0.90 to 0.92. In addition, the far-infrared radiating materials according to Examples 1 and 2 have Ats.
The 03 layer did not peel off, the mold could be easily covered by bending, and no cracks were generated at the bent portion.

On the other hand, A! Comparative Examples 1 and A where the diameter of the wire is 0.3×1
! The far-infrared emitting material according to Comparative Example 3 using a plate had an excellent far-infrared emissivity of 0.90 to 0.92, and the A72Oa layer did not peel off even after repeating the heat cycle 30 times. Due to poor flexibility, it was difficult to cover the mold, and in Comparative Example 1, cracks occurred at 3 places in the folded part, and in Comparative Example 3, cracks occurred in 108 places in the folded part.

Also, A! In the far-infrared emitting material according to Comparative Example 2, in which the Q03 layer was as thin as 3 μm, the AImOa layer did not peel off even after repeating the heat cycle 30 times, and no cracks were generated at the bent portion. The ratio was low at 0.78 to 0.82.

Furthermore, the far-infrared emitting material according to Comparative Example 4, in which slurry was sprayed onto a steel plate, had a low far-infrared emissivity of 0.87 to 0.90, and cracks occurred at the third heat cycle. A720 on the surface layer on the 7th time. The layers have peeled off. Moreover, this far-infrared ray emitting material also had poor flexibility, making it difficult to cover the mold, and the AI20* layer peeled off during bending.

[Effect of the invention] As explained above, according to the present invention, the wire diameter is 0.2■■
A below! Or A! An alumina coating with a thickness of 5 μm or more (A72
Since the far-infrared ray emitting material was constructed by weaving the strands on which the At. 03 layer and A! Or A! Since the adhesion between the alloy wire and the wire rod is excellent, the A7203 layer will not peel off even if subjected to repeated thermal cycles of rapid heating or cooling. In addition, this far infrared ray emitting material is A! Or A! It has excellent flexibility because it has a wire coated with Aj203 layer woven into the surface of the wire made of thin alloy wire, so it can be bent into complicated shapes, and this bent part can be flexibly deformed. Even if subjected to mechanical deformation, cracks occur in the Aj203 layer on the peripheral surface of the Aj or AI alloy wire, and this AI2
The 03 layer does not peel off.

Therefore, the far-infrared radiation material according to the present invention can easily cover a heating element with a complicated shape, and by using this far-infrared radiation material, A! A far-infrared heater with excellent mechanical and thermal peeling resistance of the 203 layer and excellent far-infrared radiation can be manufactured.

[Brief explanation of drawings]

FIG. 1(a) is a plan view showing a far-infrared ray emitting material according to an embodiment of the present invention, FIG. 1(b) is a cross-sectional view showing a wire constituting it, and FIG. 2 is a plan view showing a far-infrared radiating material according to an embodiment of the invention. FIG. 3 is a perspective view showing an example of processing a far-infrared radiating material. 1; Far-infrared radiation material, 2; Element wire, 3; Wire rod, 4; Ajz
O3 layer

Claims (1)

[Claims] (1) Constructed by weaving into a fabric a wire rod made of aluminum or aluminum alloy with a wire diameter of 0.2 mm or less, on which an alumina coating with a thickness of 5 μm or more is formed by anodizing. A far-infrared emitting material characterized by: