WO2008063173A1

WO2008063173A1 - A method for manufacturing a plate-type heater

Info

Publication number: WO2008063173A1
Application number: PCT/US2006/045167
Authority: WO
Inventors: Tae Suk Seo
Original assignee: Carbonic Heat Corporation
Priority date: 2006-11-21
Filing date: 2006-11-21
Publication date: 2008-05-29

Abstract

A method for manufacturing a plate-type heater, comprising fixing a current -carrying wire for supplying electrical energy to the front surface of an absorbent fabric, reversing the absorbent fabric and applying a heating material to the entire reverse surface of the absorbent fabric.

Description

A METHOD FOR MANUFACTURING A PLATE-TYPE HEATER

Field of the Invention

The present invention concerns a plate-type heater and a method for manufacturing a plate-type heater.

Background Art

Conventional plate-type heaters, which generate heat when electricity is applied to them, are not only clean and do not cause air pollution, but their temperature can easily be adjusted. They are noise-free, and are therefore widely used in mats and beds, bed mattresses, electric quilts and blankets, and heating devices for residential use in apartments, general residential dwellings, etc. Moreover, they are also used in heaters for commercial buildings such as offices and stores, industrial heaters for workshops, warehouses, and barracks, and in various other heaters for industrial uses. They are also used in agricultural equipment, such as greenhouses, drying systems for agricultural products, and various anti-freezing systems, such as devices for melting snow and prevention of freezing in streets and parking structures. They are also used in other applications such as, recreational use, protection against cold, household electrical appliances, devices for preventing steam formation on mirrors and glass, health care, animal husbandry, etc. Generally speaking, in line-type heaters, the heating material is first applied by the silk printing method in a ladder pattern, to a PET (polyethylene) film or a PP (polypropylene) film, and a copper or silver film is then attached, using a conductive adhesive, and used as the current- carrying wire.

Moreover, in methods for manufacturing all-surface plate- type heaters of the prior art, in separate operations for the upper component and lower component, the heating material is applied to either or both surfaces, after which they are thoroughly dried, the upper and lower components are then joined, and a copper or silver film or a copper wire, referred to as a braided wire, is firmly attached solely by extrusion laminating and used as the current-carrying wire. In extremely rare cases, carbon threads and copper wires are twisted onto both ends of carbon fiber, and this is then used instead of a braided wire.

In this process, the work generally consists of processing the current-carrying wire immediately before the final process, and the joined components are then completed after applying the heating material .

However, in the method of using a conductive adhesive, which is the method used in line-type heaters of the prior art, there are decreases in functionality caused by the phenomenon of carbonization of the adhesive, and because the customer must gradually increase the temperature in order to obtain the required heat, this gives rise to the risk of fire.

Moreover, with respect to the method of fixing the braided wire in place by extrusion coating, which is the method used in all-surface plate-type heaters of the prior art, because of people stepping on the product or continuous external impact, separation from the adhesion surface may occur, giving rise to the problem of the generation of a high degree of heat in the vicinity of the braided wire . Because of the aforementioned problems with the current- carrying wire, the only materials that can be used, in both all- surface plate-type heaters and line-type heaters, are PET or PP films that are as hard as possible. Accordingly, not only can such plate-type (line-type) heaters only be used in fixed locations, it is virtually impossible to use them in materials such as bedding and mattresses, which come into close contact with human beings .

Moreover, when the method is used of separately twisting carbon thread and copper wire onto the carbon fiber, fire frequently results, because of poor adhesion between ordinary electric wire and this braided wire .

Objects of the Invention

The purpose of the present invention is to solve the aforementioned technical problems of the prior art by providing a method for manufacturing a plate-type heater in which the risk of fire due to electrical problems is eliminated, by firmly- attaching the current-carrying wire to the heating material.

Description of the Invention

This application is an improvement over my invention described in my pending PCT Application No. US2006/026639, filed 07 July 2006, which is incorporated herein by reference.

In order to achieve the above purpose, the method for manufacturing a plate-type heater of the present invention comprises a step in which the current-carrying wire for supplying electrical energy is fixed to the front of an absorbent fabric. Next, the aforementioned fabric is reversed and a heating material is applied to the entire reverse surface of the fabric. Then, surface components are formed on the top of the aforementioned heating material and the front of the aforementioned fabric .

Preferably, the invention also comprises a further step in which, before fixing the current-carrying wire in place, a polyolefin resin is applied over the entire surface of the fabric on which the current carrying wire has been placed, in order to fix the aforementioned current-carrying wire to the aforementioned fabric. Preferably, in the step in which the current-carrying wire is fixed on the fabric, polyolefin resin is applied by, and the fixing is carried out by means of extrusion coating.

Preferably, the aforementioned fabric is of sufficient thickness to absorb the aforementioned heating material. 105 Preferably also, the heating material is applied by use of the gravure printing method.

The following is an explanation of the present invention sufficient to allow a person having ordinary knowledge in the technological field of the invention to easily implement the 110 invention, and the explanation of the preferred working example of the present invention will be made with reference to the attached figures.

The following is an explanation of the method for manufacturing a plate-type heater according to the preferred 115 working example of the present invention.

Brief Description of the Drawings

Fig. 1 is a diagram showing the structure of the plate- type heater according to a working example of the present 120 invention; and

Fig. 2 is a diagram showing the final assembly of the plate-type heater according to a working example of the present invention.

125 An explanation of the symbols indicating the main components of the invention are as follows: 11 : Fabric

12 : Current-carrying wire 13 : Heating material 14 : Polyolefin resin

15 : 2nd and 4th surface components 16 : 1st and 5th surface components

Detailed Description of the Invention Referring to Figs. 1 and 2, there is shown current- carrying wires (12) such as a braided wire or a copper or silk film, fixed by the extrusion coating method to a thin cotton fabric (11) that has outstanding strength and which is capable of absorbing a heating material, described below. An extrusion coating method is used to form a polyolefin resin layer (14) over current carrying wires (12) as part of the process for subsequently fixing the current-carrying wires (12) to the reverse side of the cotton fabric (11) .

As shown in Fig. 2, when the cotton fabric (11) with the current-carrying wires (12) fixed on it, is reversed, the portion with no polyolefin resin (14) adhering to the cotton fabric (11) is where the current-carrying wires (12) are located on the surface of the cotton fabric (11) .

A heat-generating material (13) , that is a mixed carbon solution having a high viscosity, is applied by gravure printing to the entire surface of the cotton fabric (11) , opposite to the side having the current-carrying wires (12) attached. The heat- generating material (13) will be absorbed and deposited through the gaps between the threads of the cotton fabric (11) in the

155 portion of the cotton fabric (11) to which no polyolefin resin (14) adheres, which is the portion occupied by the current- carrying wires (12) after which there is strong adhesion of the heat generating material to the current-carrying wires (12) . In addition, as the polyolefin resin (14) is applied by

160 means of the extrusion coating method, as part of a procedure to cause the current-carrying wires (12) to be attached to the cotton fabric (11) in advance, the heat-generating material (13) will be evenly applied. In addition, the heat-generating material (13) can optionally be applied by lamination several

165 times, in accordance with customer requirements.

As shown in Fig. 2, as is the case for all-surface plate- type heater manufacturing methods of the prior art, after the application of the heat-generating material (13) has been completed, both sides may be covered by first surface materials

170 (15) , and one may also use more flexible second materials (16) to cover the outside surfaces of the completed plate-type heater.

The cotton fabric (11) has a width of about 50 cm to about 200 cm, and must show no deformation at temperatures of 150°C.

175 While the working example uses cotton as the fabric, any fabric which is absorbent, such as wool, polymer, or synthetic absorbent fabric may be used.

The polyolefin resin has a melting point of about 100⁰C to about 170⁰C, and the resin extrusion coating is carried out at

180 about 300⁰C.

Application of the heat-generating material (13) by means of gravure printing is done in accordance with the requirement that the mesh size of the gravure printing roller must be about 80#-150#, and the width of the mesh printing surface is adjusted

185 to about 50 cm-200 cm so as to conform to the heating width of the plate-type heater.

If the gravure printing method is used, the concentration of the carbon composite compound (13) and the thickness of the laminate must be taken into consideration, and single or

190 multiple lamination can be carried out in accordance with customer requirements and the application in question. More precise adjustments can be made by adjusting the mesh size of the printing roller. An important factor in this case is that with a size of 80 mesh or below, the ink will blot, making

195 precise product manufacturing difficult, while at a mesh size of 150 or above, the ink will not provide sufficient coverage, making it impossible to manufacture the product. Accordingly, in the gravure printing method of the present invention, manufacturing must be carried out in all cases with a mesh size

200 of about 80#-150#. This is done so that it is possible to adjust the conductivity and amount of heat as needed under any conditions .

In the present invention, in order to solve the drawback of existing plate (line) type heaters, namely problems resulting from adhesion to the current-carrying film using a conductive adhesive, current-carrying wires (12) are fixed in place solely by lamination, without using an adhesive, and for this purpose, electric wire having an overall diameter of about 2 to about 3 mm or more (flat strip wire or braided (twisted) thin wire) is processed to compress it into as flat a shape as possible and then used. It is processed into a flat shape in order to make the surface adhering to the application surface of the carbon compound (13) wide, or during manufacturing, to reduce to a minimum any areas protruding from the surface in order to maintain an aesthetically pleasing appearance.

As discussed above, overall width can be adjusted depending on the application in question. Specifically, by adjusting the thickness of the current-carrying wires (12) , a product can be manufactured having a minimum construction width of 1 meter or more (up to 100 meters or more) without cutting.

Although the width of the plate-type heater must be large, if it is used in cases where high temperature is required, wire having a larger thickness may be used. Either alternating current (AC) or direct current (DC) can be used as a working voltage, with a voltage range of 6 V to 400 V being preferred. Furthermore, conductivity is 0-10², electrical resistance is 0-900 Ω, the application thickness of the carbon compound is 10- 100 μm, the heat-generating width is 50-200 cm, and the far infrared radiation percentage is 87.5%.

230 The approximate composition of the carbon compound (far infrared radiation conductive ink) of the plate-type heater of the present invention is 30.4% urethane polymer resin, 15.6% conductive powder (such as a carbon polymer) , 4% additives (such as an adhesive) , and 50% dilute solvent (such as water or a

235 thinner) .

In the present invention, as stated above, as current and heat are easily generated throughout the entire surface, in comparison to line-type heaters, the entire surface can be evenly heated using half the amount of heat, so there is no

240 waste whatsoever, and the wire, which is the current-carrying area, can be manufactured with a thin thickness as required by the application and the surface area in question.

In addition, as no adhesive is used on the wire, the possibility of occurrence of the phenomenon of carbonization

245 becomes lower with the passage of time, and as it is possible to adjust the thickness of the wires, there is no risk of fire resulting from heating.

Because the invention can be used without requiring cutting or connecting, operation is simple and easy, and compared to

250 line-type heaters, the heat and far infrared radiation generated can be increased by a factor of approximately 2 based on total surface area.

Moreover, as other thermoelectric conductors are not required, it is possible to use the invention, as is, in floors

255 covered with laminated paper, and in cases where induced current is generated on the heater, this current can be completely- eliminated by using shielding and grounding the device.

Generation of electromagnetic waves is also relatively low, and the carbon compound absorbs electromagnetic waves with

260 virtually no damage.

As polyolefin resin is used rather than an adhesive in extrusion lamination, the thickness of the current-carrying copper film can be selected based on the application and requirements in question, and large-width products can also be

265 manufactured (with widths up to 5 times greater than those shown by line-type heaters of the prior art) .

The all-surface plate-type heater manufactured by the above described method may be used in a variety of applications, because when the plate-type heater is crumpled or moved, the

270 heat-generating material (13) and the current-carrying wire (12) constantly remain firmly attached, with the result that there is virtually no risk of fire due to electrical problems .

Thus, there is no problem with using the invention in applications such as bedding or mattresses . There is also

275 virtually no risk of problems due to the phenomenon of carbonization or external impact.

As the outer covers (15 and 16) and the current-carrying wire (12) are made, using as flexible materials as possible, they may be used at any location where heat and far infrared

280 radiation are required.

Moreover, as the current-carrying wire (12) is thick and strong, there are virtually no problems of poor adhesion.

Using the invention, it is possible to manufacture mats and plate-type heaters of the highest electrical stability.

285 It is also possible to make any desired adjustments in the amounts of electricity and heat desired, during manufacturing, and the amount of far infrared radiation can also be controlled by means of carbon viscosity.

Specific explanations of the technical concept of the

290 present invention have been given according to preferred working examples , but it should be noted that the above working examples were given solely by way of explanation and by no means limit the present invention. Moreover, a person skilled in the art in the field of the present invention understands that numerous

295 working examples are possible within the scope of the technical concept of the present invention.

Industrial Applicability of the Invention

The plate-type heater of the present invention described 300 above has its heat-generating component and the current-carrying wire constantly and solidly attached to each other, with the result that there is virtually no risk of fire due to electrical problems .

Furthermore, there is no problem whatsoever with using the 305 invention for bedding, mattresses, etc. There is also no risk of problems due to the phenomenon of carbonization or external impact .

As the upper surface component and the current-carrying wire are made of materials that are as flexible as possible, the 310 invention may be used at any location where heat and far infrared radiation are required.

The present invention makes it possible to produce stable mats and plate-type heaters of the highest electrical stability.

The electrical capacitance or heat can be freely adjusted 315 at the time of manufacturing, and the amount of radiation from far infrared rays can also be adjusted based on carbon concentration.

Having thus described the invention, I claim:

Claims

320 Claim 1. A method for manufacturing a plate-type heater, comprising fixing a current-carrying wire for supplying electrical energy to the front surface of an absorbent fabric, reversing the absorbent fabric and applying a heating material to the entire reverse surface of the absorbent fabric.

325

Claim 2. The method for manufacturing a plate-type heater of Claim 1, further comprising applying a polyolefin resin to the front side of the absorbent fabric to fix the current- carrying wire to the absorbent fabric.

330

Claim 3. The method for manufacturing a plate-type heater of Claim 2 , in which the polyolefin resin is applied using the extrusion coating method.

335 Claim 4. The method for manufacturing a plate-type heater of Claim 1, in which the absorbent fabric has a thickness capable of absorbing the heating material .

Claim 5. The method for manufacturing a plate-type heater 340 of Claim 1, in which the heating material is applied using the gravure printing method.

Claim 6. The method for manufacturing a plate-type heater 345 of Claim 5, in which the application of the heating material is carried out by lamination.

Claim 7. The method for manufacturing a plate-type heater of Claim 1, in which the heating material is a mixed carbon 350 solution.

Claim 8. The method for manufacturing a plate-type heater of Claim 1, further comprising affixing surface components on the top of the heating material and the front of the absorbent 355 fabric .

Claim 9. The method for manufacturing a plate-type heater of Claim 1, in which the absorbent fabric is cotton, wool, polymer or synthetic material .

360

Claim 10. A method for manufacturing a plate-type heater, comprising fixing a current-carrying wire for supplying electrical energy to the front surface of a cotton fabric, applying a polyolefin resin to the front side of the cotton

365 fabric to fix the current-carrying wire to the cotton fabric, reversing the cotton fabric and applying a heating material to the entire reverse surface of the cotton fabric and affixing surface components on the top of the heating material and the front of the absorbent fabric. 370

Claim 11. The method for manufacturing a plate-type heater of Claim 10, in which the polyolefin resin is applied using the extrusion coating method.

375 Claim 12. The method for manufacturing a plate-type heater of Claim 10, in which the absorbent fabric has a thickness capable of absorbing the heating material .

Claim 13. The method for manufacturing a plate-type heater 380 of Claim 10, in which the heating material is applied using the gravure printing method.

Claim 14. The method for manufacturing a plate-type heater 385 of Claim 10, in which the application of the heating material is carried out by lamination.

Claim 15. The method for manufacturing a plate-type heater of Claim 10, in which the heating material is a mixed carbon 390 solution.