JPH0817562A - Sheet heating element - Google Patents

Abstract

PURPOSE:To conduct insulating work with heat press working without use of an adhesive and independent of the number of yarns per inch of a cloth by weaving binder fibers for bonding with an electrically insulated film between electrode parts and between synthetic resin heating systems. CONSTITUTION:In a sheet type heating element 1, a plurality of electrode parts 4 formed by bundling a plurality of electrode yarns are arranged on both lug sides and in the central part in the warp direction at specified intervals, and synthetic resin heating yarns 5 are arranged in the weft direction so as to cross to the electrode parts 4. Synthetic fibers 2, 3 with high electric resistance are woven as the warp and weft between the electrode parts 4 and the heating yarns 5 to prevent short circuit, and both sides of the cloth are covered with electrically insulating resin films 6. Since part of the synthetic resin fibers 2, 3 are constituted with binder fibers, the film 6 is heat-bonded and electrical insulation of the whole heating element 1 is ensured. The synthetic fibers 2, 3 contains at least two kinds of resins with different melting points, and the fiber containing low melting point resin functions as the binder fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet heating element used for heating elements such as carpets and heating futons.

[0002]

2. Description of the Related Art Conventionally, a heating element such as a hot carpet, a heating futon, a heating seat, etc. is used by embedding a heating element in a rug. The heating element includes a nichrome wire, a synthetic resin heating wire in which a conductive material is applied to a resin, and a film heating element in which a conductive material is applied to a film.

The synthetic resin heating wire has a high flexibility and a relatively high electric resistance value.

Therefore, it is often used by being woven into a fabric having an electrode portion.
And Japanese Patent Laid-Open No. 62-100968.

Since a nichrome wire heating element having a relatively low electric resistance value can have a long distance between electrodes, it is possible to obtain a heating element by directly applying a voltage to both ends of the nichrome wire to generate heat by energization.

A heating element using a synthetic resin heating wire is provided with a plurality of electrode portions in which a plurality of electrode yarns are converged at predetermined intervals, and a large number of synthetic resin heating wires are woven between the electrodes so as to intersect the electrode portion. A synthetic fiber with a high electric resistance is woven into a cloth between the electrodes and between the synthetic resin heating wires, and the surface of the woven cloth does not have electrical insulation, so it cannot be used as a heating element as it is. To obtain insulation, the surface of the cloth is covered with an electrically insulating resin film or the like. There are an adhesive method and a heat press method as a method of coating the surface of the cloth with a resin film. The adhesive type is a method of applying an adhesive to a cloth or film and pasting it together, and the hot press type is a method of laminating a thermoplastic resin film on both sides of a cloth woven with a coarse density and hot pressing it. The plastic resin film passes through the rough woven cloth gap and is fused and integrated with each other.

Although the adhesive type is general, there is a problem that the number of steps such as adhesive coating, adhesive drying, pressing and curing is large and the processing cost is high. The hot press type is easy to process because it is simply hot pressed and no adhesive is used, but it is necessary to make the weaving density of the heating element fabric coarse. If the weaving density of the heating element fabric is excessively rough, the adhesion between the electrode threads and the heating threads will be weakened, so there is a limit to the roughening. If the weaving density of the heating element fabric is too rough, the fabric structure will be deformed or the cutting portion will be cut. However, there is a problem that the yarn of the item is easily broken.

[0008]

In the method as described above, either the adhesive is used for the insulation processing of the heating element cloth, or the hot pressing is performed by roughening the woven structure of the cloth.

The method using an adhesive has a high processing cost, the heat pressing method has a weak adhesion between the electrode yarn and the heat generating yarn, and requires special attention to prevent the deformation of the weave structure during handling, resulting in poor productivity. There was a problem.

An object of the present invention is to provide a sheet-like heating element which can be electrically insulated by hot pressing without being restricted by the weaving density and which is less likely to deform the weave structure and has less cut surface fraying and easy handling. It is intended.

[0011]

Means for Solving the Problems The inventors of the present invention have made earnest studies to solve the above problems, and as a result, by weaving a binder fiber that adheres to an insulating film, the hot pressing process is performed regardless of the weaving density of the fabric. The present invention has been completed by finding that it is possible to perform insulation processing on a heating element fabric.

That is, according to the present invention, a synthetic resin heating yarn is arranged so that a plurality of electrode yarns are converged and intersect with an electrode portion arranged in a plurality of rows at a predetermined interval. In a sheet heating element in which both sides of a fabric woven of synthetic fibers with high resistance value are covered with an electrically insulating resin film, at least a part of synthetic fibers with high electrical resistance value is binder fiber, and both sides are connected through this binder fiber. The sheet heating element is characterized in that the electrically insulating resin film is heat-pressed.

The present invention will be described in detail below.

FIG. 1 is a schematic plan view of a sheet heating element showing an example of the present invention. In FIG. 1, a planar heating element 1 has an electrode portion 4 composed of a plurality of electrode wires arranged in a longitudinal direction of both ears and a center, and a synthetic resin heating yarn 5 is provided in a weft direction so as to intersect the electrode portions. The synthetic fiber 2 having a high electric resistance value is woven as a warp between the electrode parts, and the synthetic fiber 3 having a high electric resistance value is also woven as a weft between the synthetic resin heat generation yarns so that the electrode parts and the heat generation yarns are constant. Is kept to prevent a short circuit, and both sides of this cloth are covered with an electrically insulating resin film 6 to maintain the electrical insulation of the entire planar heating element. Then, when a voltage is applied to the electrode portion 4, a current flows through the heating yarn 5 to generate heat.

FIG. 2 is a schematic sectional structural view showing a sectional structure in which the vicinity of the electrode portion of the planar heating element of FIG. 1 is cut in the weft direction. In FIG. 2, between the electrode parts 4, there is a synthetic fiber 2 having a high electric resistance value woven as a warp between the electrode parts,
There is a synthetic fiber 3 having a high electric resistance value woven as a weft between the heating yarns 5 so that the electrode portions and the heating yarns are kept at a certain distance so as not to be short-circuited. Part of the binder fiber is composed of the binder fiber, and the electrically conductive resin film 6 on both sides is formed by this binder component.
Is thermocompression bonded, and the electrical insulation of the entire planar heating element is maintained.

Except in a special case, the sheet heating element of the present invention is provided with a plurality of electrode threads 7 which are bundled on a warp and provided as electrode portions in a plurality of rows of strips at predetermined intervals. The interval between the electrode portions is determined by the heat generation performance of the heat generating yarn, the heat generation temperature of the target sheet heating element and the like. If the electric resistance of the heating thread is about 100 ohm / cm, the power source used is 55 cm at 100 V and 15 at 24 V.
A distance between electrodes of about 5 cm at 12 cm and 12 V is suitable for obtaining the surface temperature of the heating element of 40 to 50 ° C.

The number of converged electrode threads is determined by the energizing ability of the electrode threads and the current consumption of the sheet heating element. As the electrode thread, a covering thread in which a twisted copper wire or a synthetic fiber is used as a core thread and a copper foil is wound around the surface in a tape shape is used. The copper foil covering yarn has excellent bending fatigue resistance, and it is easy to match the thermal stretchability with other fiber materials under the heat treatment temperature condition in the heating element processing step. The copper foil can also be used after being plated with another metal.

The synthetic resin heating yarn used to cross the electrode portion is obtained by coating a core yarn with a conductive resin in which conductive particles are dispersed. The yarn used for the core yarn is not particularly limited, but the core-sheath type composite fiber in which a thermoplastic resin having a low melting point is arranged in the sheath portion disclosed in JP-A-2-300378 is used as a conductive resin. A heat generating yarn having good adhesiveness is obtained, and bending fatigue resistance is improved, which is preferable. As the conductive particles,
It is not particularly limited, and any of carbon particles, graphite, metal and the like can be used, and these may be used in combination. Carbon particles include acetylene black, Ketjen black, furnace black, and the like, and graphite includes natural graphite and synthetic graphite. The metal includes gold, silver, aluminum, nickel, tin and the like, and synthetic resin or inorganic particles coated with metal by plating or vapor deposition may be used as the conductive particles. As the base resin for dispersing the conductive particles, a polyurethane resin,
Thermoplastic resins such as polyester resins, acrylic resins and butyral resins are preferred.

As a method of coating the core yarn with the conductive resin, the base resin is dissolved in a solvent to immerse the core yarn in a paste liquid in which the conductive particles are dispersed, and then the excess paste liquid is removed with a circular die. Generally, a method of heat treating to remove the solvent to solidify the conductive resin is general.

The synthetic fiber having a high electric resistance value woven between the electrode portions and between the synthetic resin heating yarns is a fiber made of synthetic resin having a volume resistivity of 10 ¹⁴ ohm · cm or more. As the synthetic resin, polyester resin is used. , Nylon resin, acrylic resin, polyolefin resin and the like. Also,
The synthetic fiber having a high electric resistance value may be filament yarn or spun yarn, may be monofilament or multifilament, and may be crimped or the like. However, a high-velocity air is ejected from a nozzle to create a turbulent air flow, and the multi-filament is passed through the turbulent air flow region to form cross-filament filaments, loops, crimps, etc. In that case, since the surface of the heating element has complicated filament disorder, slippage between threads is prevented, and deformation of the woven structure of the heating element fabric and fraying of the cut portion can be prevented, which is preferable.

Further, the synthetic fiber having a high electric resistance value contains at least two kinds of resins having different melting points, and the fiber having the resin having a lower melting point serves as a binder fiber which contributes to the adhesion with the electric insulating film. Shall work. The resin that functions as a binder may be a resin of the same type or a resin of a different type, but the resin having a high melting point is mainly selected in consideration of the adhesiveness between the fibers that form the fabric and the electrical insulating film. Is preferred. Further, the binder fiber may be a single component fiber consisting only of the resin having the lower melting point, but the resin having the higher melting point is arranged in the core part, and the resin having the lower melting point which becomes the binder component is arranged in the sheath part. It is also possible to use arranged core-sheath composite fibers.

In the fluid disturbance processing, the feed rate of the binder fibers is increased by using a two-feed facility, and the fluid disturbance processed yarn is made into a double structure of a core-sheath structure and the binder fibers are mainly arranged in the sheath portion. Can also be used.

When weaving the fabric for the sheet heating element of the present invention, it is easy to change the electrode thread to the warp direction and the heating thread to the weft direction so that the heating elements have different heating capabilities. It is also advantageous in terms of productivity. Further, only the binder fiber or the yarn containing the binder fiber may be used as the yarn other than the electrode yarn and the heat generating yarn, but the binder fiber or the yarn containing the binder fiber may be used only for the warp yarn or the weft yarn. It may be designed in consideration of the adhesiveness with the insulating film.

When the electrically insulating film is a vinyl chloride resin, polyamide resin is preferable for the sheath portion of the binder fiber. When the electrical insulation film is polyester resin,
The sheath portion of the binder fiber is preferably a polyester copolymer resin.

The electrically insulating resin film covering both surfaces of the sheet heating element to ensure the electrical insulation is preferably made of a thermoplastic resin having a volume resistivity of 10 ¹⁴ ohm · cm or more. As this resin, a vinyl chloride resin, a polyester resin, a polyolefin resin, or the like can be used. The coating of the film is preferably carried out by superposing an electrically insulating resin film on the front and back of the cloth for the sheet heating element, and hot pressing at a temperature higher than the melting point of the binder fiber. In this case, it is preferable to use an electrically insulating resin film having a melting point of 120 to 160 ° C. because it is easy to sufficiently bond the films at the peripheral edge portions to each other.

[0026]

The electrically insulating resin film on the surface of the sheet heating element of the present invention is thermocompression-bonded by the binder fiber between the electrode parts and between the heating yarns, so that no adhesive is used and the fabric density is limited. The adhesive process can be easily performed without causing the fabric structure to be easily frayed.

[0027]

EXAMPLES Next, the present invention will be specifically described with reference to examples.

Example 1 A polyester multifilament 250d / 24f (melting point 255 ° C.) having a volume resistivity of 10 ¹⁴ ohm · cm was applied to a core thread with a width of 0.5 mm and a thickness of 0.1 mm tin-plated copper foil tape 2050T. Figure 1 shows the electrode thread obtained by covering at
36 pieces of polyester multifilament 500d / 70f are arranged side by side in both ears and in the central part, like an AT machine manufactured by Aikiki Co., Ltd.
emajet 341 Type was installed, and 430 yarns were entangled at an air pressure of 5 cm / cm ² at a feed rate of 5% and a processing speed of 100 m / min. This arrangement is used as a warp, a weft is used as a heat generating yarn, and a core is made of nylon 6-nylon 66 having a melting point of 210 ° C.
A 420d core / sheath composite monofilament yarn in which a copolymer resin and a nylon 6/12 copolymer resin having a melting point of 140 ° C. are arranged in a sheath is a thermoplastic polyurethane resin [trade name: Crisbon 8
566, Dainippon Ink and Chemicals, Inc., dimethylformamide solution (solid content 20% by weight)] 1100 parts of acetylene black with an average particle size of 53 microns [trade name: Denka Black HS-100, manufactured by Denki Kagaku Kogyo Co., Ltd. ], 20 parts, synthetic graphite having an average particle diameter of 50 microns [trade name: Fine powder SGP50, manufactured by SEC Co., Ltd.], 20 parts, isocyanate cross-linking agent [trade name: Barnock DN950, manufactured by Dainippon Ink and Chemicals, Inc.] 5 parts of each was soaked in the carbon paste added, stirred, and mixed, passed through a circular die with a diameter of 1.3 mm, and then heat-treated in an oven at 160 ° C. Electric resistance 110Ω /
cm yarn and binder fiber, melting point 215 in core
℃ Nylon 6 resin, sheath has a melting point of 145 ℃ Nylon 6 resin
Using 1000 denier nylon monofilament core-sheath composite yarn composed of 12 copolymer resins in a ratio of 1: 3,
Total width 1140mm, electrode width 10mm, interelectrode width 550m
m, a warp density of 20 yarns / inch, and a weft density of 20 yarns / inch were obtained.

The heating element fabric obtained was cut into a length of 1000 mm, and the volume resistivity was 10 ¹⁴ ohm · cm and the thickness was 400.
Micron vinyl chloride film [Product name: Arturon film, Mitsubishi Vinyl Chemical Co., Ltd.] is cut into a size of 1160 mm in width and 1020 mm in length, two pieces are prepared, and the film is superposed on both sides of the heating element fabric. Using a press with a heater, temperature 180 ℃, pressure 500g / cm ²
The sheet was heat-pressed for 150 seconds to obtain the sheet heating element of the present invention.

The vinyl chloride film peeling strength of the obtained sheet heating element is 3 to 4 kg / 25 mm width, and sufficient adhesive force is obtained to be used as a sheet heating element, and the deformation of the woven structure is small and the cut surface is small. There were few frays. Also,
The heating element cloth before covering with a vinyl chloride film is 160
It was found that there was no deformation of the woven structure and no fraying of the cut portion even when heat set with hot air at ℃, and it could be processed by automatic cutting or an automatic heat laminating machine.

Example 2 An electrode thread obtained by covering a polyester multifilament 250d / 24f (melting point 255 ° C.) on a core thread with a tin-plated copper foil tape having a width of 0.5 mm and a thickness of 0.1 mm at 2050 T / m. As shown in Fig. 1, 36 pieces are arranged side by side in both ears and in the center, and Hemaline 3 air nozzle Hemajet 3
Using an AT machine manufactured by Aiki Co., Ltd. equipped with 41 Type, a polyester multifilament 250d / 48f having a volume resistivity of 10 ¹⁴ ohm · cm was supplied as a core yarn at a feed rate of 5%, and a core portion was formed as a sheath yarn. A core-sheath composite polyester filament 15 in which polyethylene terephthalate (melting point: 255 ° C.) and polyester (polyethylene terephthalate: 40 mol% copolymerized with 40 mol% of isophthalic acid) (melting point: 110 ° C.) as a binder component in a sheath portion are arranged at a ratio of 1: 1.
0d / 30f is fed at a feed rate of 20% and the air pressure is 5
430 yarns interlaced at kg / cm ² and a processing speed of 100 m / min. are arranged between the electrode yarns, respectively 430 yarns and 4 yarns outside the electrode yarns of the ears, as warp yarns, and the weft yarns as heat generating yarns. 420d core-sheath composite monofilament yarn in which nylon 6/66 copolymer resin having a melting point of 210 ° C and nylon 6/12 copolymer resin having a melting point of 140 ° C is arranged in a thermoplastic polyurethane resin [trade name: Crisbon 8566, Dainippon Ink and Chemicals, Inc., dimethylformamide solution (solid content 20% by weight)] 1100 parts with an average particle size of 5
3 micron acetylene black [trade name: Denka Black HS-100, manufactured by Denki Kagaku Kogyo Co., Ltd.] 20
Parts, synthetic graphite with an average particle size of 50 microns [trade name: Fine powder SGP50, manufactured by SEC Co., Ltd.]
20 parts, and 5 parts of an isocyanate cross-linking agent [Brand No. DN950, manufactured by Dainippon Ink and Chemicals, Inc.] were added, stirred and mixed, and then immersed in a carbon paste and passed through a circular die having a diameter of 1.3 mm. A total width of 1 using a yarn of 110 Ω / cm in electrical resistance heat-treated in an oven at 160 ° C and a yarn of the above-mentioned entanglement process at a ratio of 1: 3.
A heating element fabric having a width of 140 mm, an electrode width of 10 mm, an interelectrode width of 550 mm, a warp density of 20 yarns / inch, and a weft yarn density of 20 yarns / inch was obtained.

The obtained heating element fabric was cut into a length of 1000 mm, and a polyester film having a thickness of 50 μm was cut into a width of 1160 mm and a length of 1020 mm, and two sheets were prepared. The films were superposed on both sides and heat-pressed for 150 seconds at a temperature of 150 ° C. and a pressure of 500 g / cm ² using a pressing machine equipped with a single-sided heater to obtain the sheet heating element of the present invention.

The vinyl chloride film peeling strength of the obtained sheet heating element is 3 to 4 cm / 25 mm wide, and sufficient adhesive force is obtained to be used as a sheet heating element, and the woven structure is less deformed and the cut surface is reduced. There were few frays.

[0034]

According to the present invention, it is possible to provide a sheet heating element which is easy to handle because the deformation of the weave structure is small and the cut surface is not frayed easily, and which is advantageous in terms of cost.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a sheet heating element showing an example of the present invention.

FIG. 2 is a schematic cross-sectional structural view near an electrode portion of an ear portion of the planar heating element of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet heating element 2 Synthetic fiber with high electric resistance value 3 Synthetic fiber with high electric resistance value 4 Electrode part 5 Heating thread 6 Electrical insulating resin film 7 Electrode thread

Claims (1)

[Claims] 1. A synthetic resin heating yarn is arranged so that a plurality of electrode yarns are converged and intersect with an electrode portion arranged in a plurality of rows at a predetermined interval, and a high electric resistance value is provided between the electrode portions and between the synthetic resin heating yarns. In a sheet heating element in which both sides of a fabric woven with synthetic fibers are covered with an electrically insulating resin film, at least a part of the synthetic fibers having a high electric resistance value is a binder fiber,
A sheet heating element, characterized in that the electrically insulating resin films on both sides are thermocompression bonded via the binder fiber.