JPH0654706B2 - Method of manufacturing surface heating tool - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sheet heating device mainly used as an electric carpet.

2. Description of the Related Art Conventionally, a non-woven fabric such as needle punch felt or a French pile has been used as a surface cloth used for an electric carpet or the like, and its surface is relatively smooth and hard without cushioning. In such a smooth surface cloth such as needle punch felt, hot press bonding was easy using a hot-melt adhesive, whereas a napped surface cloth with good cushioning property such as general carpet was fluffed in the hot pressing step. Therefore, there are various difficulties and restrictions in using the napped surface cloth for the electric carpet having the heater incorporated therein. Specifically, as a method of adhering the napped surface cloth to the heater unit, a method of fusing the hot melt adhesive by hot pressing and a method of adhering the hot melt adhesive at the same time as applying the solvent-based or aqueous emulsion-based adhesive There is a method of laminating and bonding over time, a method of chemically cross-linking and curing in a short time after coating an adhesive, and then bonding.

Problems to be Solved by the Invention However, this method has a problem that the naps fall and the texture is impaired. Also, in the case of a thick outer cloth, the bonding heating time is long. However, the method is difficult in terms of process and causes a large process loss. In the case of the method (1), the solvent odor is severe in the case of the solvent type, and the long adhesion time is required in the aqueous emulsion type.
Further methods have limited materials, and very few materials satisfy various performances.

The method for manufacturing a surface heating tool of the present invention solves the problem of such inefficiency and impairs the texture of the outer cloth, and is efficient in terms of time and cost and has a good texture. The present invention provides a method for manufacturing the same.

Means for Solving the Problems A method for manufacturing a planar heating tool according to the present invention which solves the above problems is to heat an upper and lower planar base material with an adhesive having a large dielectric loss factor interposed therebetween by a dielectric heating method. A method of adhering two upper and lower sheet base materials for a sheet heating tool.

Operation According to the above method, the adhesive having a large dielectric loss is dried and solidified by the dielectric heating method, and the two planar base materials are adhered to each other.

Examples Hereinafter, the present invention will be described based on Examples.

(Example 1) As shown in FIGS. 3 and 4, a heat insulating felt 1, a flexible heating wire incorporation base material (also referred to as a non-woven fabric) 2 and a pile (puffed) surface cloth 3 are overlaid and electrically connected. In making a carpet, a heating wire incorporating base material 2 incorporating a flexible heating wire 2a and an adiabatic felt are piled up, and ethylene-vinyl acetate is placed on the nonwoven fabric 2 by a roll coater 6 as shown in FIG. Copolymer emulsion adhesive 5 is applied 5a. The non-woven fabric 2 used at this time was a thin one having a thickness of 0.1 mm, and both sides of the non-woven fabric could be coated through the gaps between the fibers. The top cloth 3 was put on this, placed between the electrode plate 7 and the vapor-absorbing electrode plate 8, a high-frequency electric field was applied by a high-frequency power source 9 of 12 MHz, and heating was performed for 16 seconds. At the same time, the depressurizing device 11 having the trap 10 was operated to efficiently absorb the generated steam, and the electric carpet main body was adhered in a short time and dried and solidified. Adhesion strength by peeling method immediately after adhesion is 7 kg /
It was 2 cm wide.

(Example 2) As shown in FIG. 5, after the heat insulating felt 1 and the heating wire incorporating substrate 2 were overlaid, the same adhesive 5 as in Example 1 was applied using the roll coater 6. First, put the pile cover cloth 3 on the first
It passed continuously between the counter electrodes 7a and 7b, between the second counter electrodes 7c and 8, and between the third counter electrodes 7d and 7e. A high frequency electric field of 12 MHz was continuously applied to these electrodes. In addition,
The convey speed of the conveyor 12 was 30 cm / sec. The decompression device for the vapor absorbing electrode plate 8 was also continuously operated. The adhesive strength of the thus obtained electric carpet body showed a width of 8 kg / 2 cm by the peeling method.

(Example 3) In Example 3, instead of the adhesive 5 in Example 1, a polar solvent type adhesive in which polyurethane was dissolved in a mixed solvent of butanone and tetrahydrofuran was used, and a surface condition was obtained in the same manner as in Example 1. I got a warming tool. The characteristics of this surface heating tool are the same as those in the first embodiment.

As is clear from the above examples, in the present invention, an aqueous emulsion type adhesive or polar solvent type adhesive having a large dielectric constant is used as the adhesive. Water and polar solvents have very high permittivity and loss factor. Among the organic solvents, protonic solvents are suitable for the present invention. As the water-based emulsion type adhesive, acrylic resin, ethylene-vinyl acetate copolymer, polyvinyl acetate, vinyl urethane, maleic anhydride resin and adhesives containing these copolymers as main components are used. It contains a lot of water and is heated very well by dielectric heating.

The present invention is also characterized by providing a generated vapor absorbing means for efficiently absorbing a large amount of water generated during heating and bonding. A vapor-absorbing electrode plate that embodies this generated vapor-absorbing means can be obtained by pasting a cloth having affinity for vapor on a metal electrode plate, but it is necessary to replace this cloth from time to time. Occurs. Desirably, by forming a large number of holes 8a in the metal electrode plate 8 and forming the holes into a box shape capable of vacuum suction as shown in FIG. 2, vapor can be efficiently absorbed and the bonding time can be shortened.

The same applies to the case of a polar solvent type adhesive, and among them, a proton-based solvent has a large dielectric loss factor and often generates heat under a high frequency electric field.

In the present invention, the organic polymer material constituting the felt or outer cloth generally has a small dielectric constant of 5 or less, and among them, the soft polyvinyl chloride composition is relatively large, 5 to 10. On the other hand, since the organic solvent is a liquid, its dielectric constant is relatively large, and many polar solvents have a dielectric constant of more than 20. Among them, the proton-based solvent has a large dielectric constant similar to that of water due to the action of hydrogen bond of protons, and has a value exceeding 100 like formamide (dielectric constant: 111) which is a strong proton-based solvent. The proton-based solvent has a preferable property that, as protons move by an electric field and also serve as an isoelectric carrier, a large dielectric loss is generated like water, and as described above, heat is often generated under a high frequency electric field. As the proton-based solvent, alcohol,
Tetrahydrofuran, ethylene glycol monoether (cellosolve), formamide, ethylene glycol,
There are various solvents such as formic acid. Specific polar solvent adhesives include varnishes of polar resins such as polyurethane, polyamide, vinyl acetate copolymer and rubber, as well as general polar solvent adhesives. However, in terms of factory environment, the aqueous emulsion system has a lower solvent odor and is practical.

In the dielectric heating method of the present invention, an adhesive having a high dielectric loss factor is heated under a high-frequency electric field, and the adhesive is bonded by applying microwaves.
As the high frequency electric field, one in the range of 2 MHz to several tens MHz is used. Among them, about 6 to 80 MHz is practical.
When applying this dielectric heating method, it is efficient that only the adhesive is heated best and the other substrates are heated less directly. That is, it is important that the dielectric loss factor of the adhesive is orders of magnitude higher than that of other base materials. The aqueous emulsion type or polar solvent type adhesive of the present invention satisfies this condition. When the adhesive base material has a flexible linear heating wire, high-frequency waves propagate in the conductor, so that a local heating phenomenon is likely to occur due to the discharge phenomenon or the shape at the end of the conductor wire. Since the wire is a continuous wire without a heat insulating portion, the high frequency waves are spread and propagated in the direction of the wire, and the local heating effect in the high frequency electric field hardly occurs. Further, since the heat-producing conductor wire is generally made of a high-conductivity material such as a copper alloy, the amount of heat generated by the conductor wire due to this high-frequency electric field is small and almost negligible. Further, even in the case of an electric wire having a soft polyvinyl chloride jacket having a relatively large dielectric constant (ε = 5 to 10), the adhesive loss ratio of the adhesive in the present invention is an order of magnitude larger, and therefore the adhesion of the present invention The method is very effective.

Further, the pile surface cloth in the present invention refers to surface cloth such as shaggy, tufted, knit, loop and morquet.

EFFECTS OF THE INVENTION As is apparent from the above description, the present invention provides an efficient method for manufacturing a surface heating tool represented by an electric carpet, and is highly efficient in terms of cost and time. It is possible to obtain a surface heating tool.

[Brief description of drawings]

FIG. 1 is a process diagram showing a method for producing an electric carpet by dielectric heating in Embodiment 1 of the present invention, and FIG. 2 is a structural diagram showing an example of a vapor absorbing electrode for dielectric heating in the present invention,
3 and 4 are perspective and sectional views showing the structure of the electric carpet, and FIG. 5 is a process drawing showing the method for manufacturing the electric carpet in the second embodiment. 1 ... Insulating felt, 2 ... Heater embedded substrate, 3 ... Pile face cloth, 5 ... Water-based emulsion adhesive, 6 ... Roll coater, 7 ... Electrode plate, 8 ... Vapor absorbing electrode Board, 9
...... High frequency power supply, 10 ...... Trap, 11 ...... Decompression device.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shuji Yamamoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Wataru Ichihara 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (6)

[Claims] 1. An upper and lower sheet-shaped substrate having an aqueous emulsion type adhesive or a polar solvent type adhesive and a flexible heating wire disposed between the electrodes at least, and heated by dielectric heating. Then, a method for manufacturing a planar warming tool, wherein moisture or solvent vapor generated during the heating is absorbed by the generated vapor absorbing means, and the two upper and lower planar base materials are integrally bonded. 2. The method for manufacturing a planar heating tool according to claim 1, wherein the generated vapor absorbing means is integrated with at least one of the dielectric heating electrodes. 3. The planar heating device according to claim 1, wherein at least a pair of electrodes are composed of a plurality of pairs of electrode plates, and the planar heating device is moved continuously or intermittently and adhered. Production method. 4. A non-woven fabric sheet on which flexible heating wires are wired and fixed is arranged between at least one sheet-like substrate which is previously coated with an emulsion type or polar solvent type adhesive. The method for manufacturing a sheet heating device according to claim 1, wherein the sheet heating device and the sheet heating device are bonded. 5. The emulsion adhesive is acrylic resin,
The surface heating tool according to claim 1, which is an adhesive containing one of ethylene-vinyl acetate copolymer, polyvinyl acetate, vinyl urethane, maleic anhydride resin and a copolymer thereof as a main component. Production method. 6. The surface heating device according to claim 1, wherein the upper side base material is a needle punch felt or pile surface cloth as a heating surface, and the lower side surface base material is a heat insulating material made of felt or urethane foam. Production method.