JPH07112722B2 - Inorganic fiber flame retardant cylinder - Google Patents

Description

TECHNICAL FIELD The present invention relates to a flame-retardant tubular body based on an inorganic fiber,
More specifically, the present invention relates to a flame-retardant tubular body having excellent heat resistance, which is lightweight, easy to process, excellent in heat retention and heat insulation, and suitably used as a material for a duct for blowing hot air.

2. Description of the Related Art As a material for a duct used for blowing air inside a building, an aluminum foil layer is laminated on the inner peripheral surface of a paper cylinder originally formed by spirally winding a paper strip (Japanese Utility Model Application No. 32-12318). No.) was used a lot, but since this is not incombustible and is flammable, it cannot be used due to subsequent legal regulations. Therefore, recently, a duct is wrapped with a thin metal plate in a spiral shape. The non-combustible metal cylinder formed by this is used exclusively.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, the metal duct cylinder described above is relatively heavy and has a drawback that it is difficult to perform cutting, joining, and mounting operations at a construction site. Moreover, since the metal duct is poor in heat insulation and heat insulation, the circumference of the duct must be covered with a heat insulation material such as glass fiber for heat insulation and heat insulation.
There was a problem that the construction became complicated.

The present invention has been made in view of the above circumstances, and has excellent heat resistance, is lightweight, is easy to process, and is excellent in heat retention and heat insulation. Therefore, the present invention can be suitably used as a duct material or the like. A flame-retardant cylindrical body is provided.

Means for Solving the Problems That is, in order to achieve the above object, the present invention covers the inner peripheral surface and the outer peripheral surface of a cylindrical substrate formed of inorganic fiber or a mixed paper obtained by mixing inorganic fiber and phosphate ester pulp. Inner metal foil and outer metal foil, respectively, and an inner fiber layer and an outer fiber made of a mixed paper in which inorganic fibers or inorganic fibers and phosphoric acid ester pulp are mixed to cover the inner metal foil layer and the outer metal foil layer. A flame-retardant tubular body made of an inorganic fiber, characterized in that the inner fiber layer and the outer fiber layer are respectively impregnated with a thermosetting resin while laminating the layers.

The flame-retardant cylinder of the present invention has a flame-retardant property because the main body of the flame-retardant tubular body and the inner and outer fiber layers are made of inorganic fibers or a mixed paper prepared by mixing inorganic fibers and phosphate ester pulp. Moreover, it is lightweight and easy to process. Further, by interposing an inner metal foil layer and an outer metal foil layer between the substrate and the inner and outer fiber layers, respectively, the inside of the cylinder is divided, and both metal foil layers are made to be only fibers, and the inner and outer fiber layers are formed. By impregnating each of the fiber layers with a thermosetting resin, heat retention and heat insulation are high, and heat resistance is improved.

In the present invention, since the metal foil is interposed in the tubular structure, absorption of heat from the outside and dissipation of heat from the inside can be prevented, and at the time of impregnation with the thermosetting resin, the metal foil is used. Prevents the internal substrate from being impregnated with resin, and the resulting cylindrical body can be kept lightweight. Further, since the base layer between the metal foils is not impregnated with the thermosetting resin, the fibrous material is porous and contains air, and therefore has a heat retaining effect.

EXAMPLES Next, the present invention will be specifically described with reference to examples, but the present invention is not limited to the following examples.

Embodiment The drawings show an embodiment of the present invention. In the figure, 1 is a cylindrical substrate made of inorganic fiber or a mixed paper of inorganic fiber and phosphate ester pulp, 2 is an inner metal foil layer laminated to cover the inner peripheral surface of the substrate 1, and 3 is an outer peripheral surface of the substrate 1. An outer metal foil layer 4 covered and laminated, 4 is an inner fiber layer made of inorganic fiber or a mixed paper of inorganic fiber and phosphate ester pulp laminated to cover the inner metal foil layer 2, and 5 is an outer metal foil layer 3. An outer fiber layer composed of inorganic fibers or mixed paper laminated to cover,
A main body 6 is constituted by the base body 1, the metal thin layers 2 and 3 and the fiber layers 4 and 5. The inner fiber layer 4 and the outer fiber layer 5 are each impregnated with a thermosetting resin.

Here, the type of the inorganic fiber forming the substrate and the inner and outer fiber layers or the mixed paper of the inorganic fiber and the phosphate ester pulp is not limited, but glass fiber, asbestos, rock wool or the like is used as the inorganic fiber. As the mixed paper, it is particularly preferable to use a mixed paper having the same weight ratio of the inorganic fibers and the phosphoric acid ester pulp as described above in a weight ratio of 70:30 to 30:70 from the viewpoint of heat resistance and the like.

Further, as the inorganic fiber or a mixed paper of the inorganic fiber and the phosphate ester pulp, it is preferable to use one having a weight of about 50 to 600 g / m ² .

Note that specifically, for example, among the inorganic fibers, glass fibers having a specific gravity of 2.54 and heat resistance of about 840 ° C. can be preferably used, and as the phosphate ester pulp, normal pulp is treated with a phosphate ester chemical. A flame-retardant material can be preferably used.

Further, the kind of metal foil forming the inner and outer metal foil layers is not limited, but it is preferable to use an aluminum foil in terms of lightness and the like.

Further, the kind of the thermosetting resin with which the inner and outer fiber layers are impregnated is not particularly limited, but it is preferable to use a phenol resin, an epoxy resin or a silicone resin from the viewpoint of increasing the heat resistance of the cylinder. The impregnated amount is preferably 50 to 300% by weight (weight when cured) of the inorganic fiber or the mixed paper.

In this case, the size and shape of the cylindrical body of the present invention can be appropriately determined according to the purpose of use and the like, and for example, the shape can be formed into a long cylindrical shape, a rectangular cylindrical shape or the like in addition to the cylindrical shape described above. The thickness of each layer of the tubular body is not limited, but the thickness ratio between the base and the inner fiber layer is about 10: 1 to 3: 1, and the thickness ratio between the base and the outer fiber layer is 10: It is preferably about 1 to 3: 1. Furthermore, the thickness of the inner metal foil layer and the outer metal foil layer is 8 to 500 μm, respectively.
It is preferably about m.

Although the method for producing the present invention is not limited, for example, by winding a paper strip of an inorganic fiber paper or a mixed paper and a strip of a metal foil into a spiral-shaped multi-layer using a Langston production apparatus,
After the inner fiber layer, the outer metal foil layer, the substrate, the outer metal foil layer, and the outer fiber layer are sequentially formed to manufacture the main body, the inner fiber layer and the outer fiber layer of the main body are made to absorb the liquid thermosetting resin. It can be obtained by curing this. In this case, it is possible to manufacture flame-retardant cylinders of various shapes by appropriately deforming the main body after absorbing the liquid resin and before curing. It should be noted that as the adhesive when the main body is manufactured by the Langston manufacturing apparatus, vinyl acetate-based adhesive, phenol-based adhesive or the like can be preferably used, but the phenol-based adhesive ensures flame retardancy. It is preferable in terms.

In addition, since the main body can be easily manufactured by using the Langston manufacturing apparatus in this way and the inside of the main body can be surely divided by the metal foil, only the inner and outer fiber layers are impregnated with the flame-curable resin. It is possible to

Next, a production example of the cylindrical body of the present invention will be shown.

Production example Mixed papermaking ratio of glass fiber and phosphate ester pulp (weight ratio)
20 cm wide, 1 mm thick paper strip and width 2 consisting of 70:30 mixed paper
After forming a body 6 (inner diameter 13 cm, outer diameter 15 cm) as shown in the drawing by winding a 0 cm, 15 μm thick aluminum foil strip in a spiral shape using a Langston manufacturing apparatus,
Phenolic resin in the inner and outer fiber layers 4, 5 of the fiber layer 1
Absorb at a rate of 00% by weight (weight after curing),
The cylinder of the present invention was obtained by curing. In addition, paper strip,
A phenolic adhesive was used to bond the strip of aluminum foil. The cross-sectional structure of the cylindrical wall portion is as shown in the table below.

When the heat resistance of the above-mentioned cylindrical body was examined, it was found to be a quasi non-combustible grade in the flame retardancy test, and it was confirmed that it has sufficient heat resistance. In addition, this product was lightweight and excellent in heat retention and heat insulation.

EFFECTS OF THE INVENTION As described above, the flame-retardant tubular body of the present invention has high heat resistance, is lightweight, and is excellent in heat retention and heat insulation. Therefore, the cylindrical body of the present invention can be suitably used as a material for a duct that blows hot air, can easily perform work on site during construction, and covers the duct with glass fiber or the like for heat retention and heat insulation. There is no need to do it, and the construction can be simplified.

[Brief description of drawings]

The drawings are sectional views showing an embodiment of the present invention. 1 ... Substrate, 2 ... Inner metal foil layer, 3 ... Outer metal foil layer, 4 ... Inner fiber layer, 5 ... Outer fiber layer, 6 ... Main body.

Claims (4)

[Claims] 1. An inner metal foil and an outer metal foil are laminated to cover an inner peripheral surface and an outer peripheral surface of a tubular substrate formed of a mixed paper in which inorganic fibers or inorganic fibers and phosphoric acid ester pulp are mixed, respectively, and The inner fiber layer and the outer fiber layer are laminated with the inner fiber layer and the outer metal foil layer, respectively, and the inner fiber layer and the outer fiber layer, which are made of a mixed crystal paper obtained by mixing inorganic fibers or inorganic fibers and phosphoric acid ester pulp, are laminated. A flame-retardant tubular body made of an inorganic fiber, characterized in that each layer is impregnated with a thermosetting resin. 2. The flame-retardant cylinder according to claim 1, wherein the inorganic fiber is glass fiber, asbestos or rock wool. 3. The flame-retardant property according to claim 1 or 2, wherein the mixed paper has a mixing ratio of the inorganic fiber and the phosphate ester pulp of 70:30 to 30:70 by weight. Cylinder. 4. The flame-retardant cylinder according to any one of claims 1 to 3, wherein the thermosetting resin is a phenol resin, an epoxy resin or a silicone resin.