KR100909930B1 - Planar heating element and its manufacturing method - Google Patents

Abstract

The present invention relates to a continuous film type planar heating element and a method of manufacturing the same. More specifically, the heating module, which is one of the core elements of the planar heating element, is mixed with carbon yarn, pulp, polyester phosphorus, carbon black and functional filler. A method of manufacturing a heat generating paper that is a heat generating module capable of generating a uniform front surface by generating paper, and specially treating the heat generating paper to form an electrode, and melting the treated heat generating paper and the insulating film using a T-die. The present invention relates to a planar heating element that is manufactured by adhering with a stable adhesive even at high temperatures through adhesion.

Planar heating element, carbon black, T-die, anca coating, gravure printing

Description

Planar heating element and a method of preparing the same

The present invention relates to a continuous film type planar heating element and a method of manufacturing the same. More specifically, the heating module, which is one of the core elements of the planar heating element, is mixed with carbon yarn, pulp, polyester phosphorus, carbon black and functional filler. The method of manufacturing a heat generating paper that is a heating module capable of generating a uniform front surface by generating a paper form, and after forming the electrode after special treatment of the heat generating paper, the treated heat generating paper and the insulating film through the melt bonding using a T-die The present invention relates to a planar heating element that is manufactured by adhesion treatment with a stable adhesive even at high temperatures.

Recently, development and application of planar heating elements using self-resistance of carbon have been actively progressed. These carbon planar heating elements are easy to control the temperature, are not polluted by air, are hygienic and noise-free, and emit far-infrared rays, which are beneficial to the human body. have.

Initially, the planar heating element is a planar heating element manufactured by weaving conductive fibers such as carbon yarn, metal yarn, and nichrome yarn together with a single or non-conductive fiber to form a conductive fabric as a heating module, and according to Korean Utility Model Publication No. 20-0226764. Yes is representative. This type of planar heating element is expensive because the heating module itself is expensive, and the stability of the electrode arrangement method for applying electricity to the heating module has not been verified yet, thus increasing the risk of fire. It is thick, which is disadvantageous in terms of thermal efficiency. This type of product does not solve the problems of fire risk, poor thermal efficiency and local overheating, so it is hardly found in the current market.

Another type of planar heating element is a method of forming a heating module by applying a conductive material having a predetermined resistance in a predetermined pattern to an insulator, and generating a heating module by applying a voltage thereto. Paste prepared by mixing carbon powder and binder is printed by screen printing method and calorique is produced by insulated bonding with PET film treated with ethylene vinyl acetate (EVA) or polyethylene (PE) adhesive. It is in commercial production by many companies at home and abroad, including MA (USA). This type of planar heating element has the advantage of being able to mass-produce a continuous film type product inexpensively, but it is impossible to produce a uniform front heating product, and it is limited in raising the exothermic temperature due to the resistance characteristic of carbon paste, and a wide product. There is a limit to the production, due to the fatigue characteristics of the carbon black and the binder, there is a disadvantage that the heat generation performance decreases as the period of use elapses.

Due to these problems, a heat generating module that has recently been in the spotlight, is a planar heating element that uses a heat generating paper made of paper by mixing carbon with pulp as a heat generating module. Korean Patent No. 0337609, US Pat. 281293 is a typical example. When the heat generating paper is used as a heat generating module, it is possible to produce a heat generating paper which is a cheap heat generating module, and a stable heat generating module which does not cause deterioration of heat generating performance even after a period of use due to thermal stability due to the crystal structure of carbon company is possible. Due to the excellent conductivity of the carbon company, it is possible to produce a high temperature heating module and a long width planar heating element product. However, in the heating paper composed of only a combination of pulp and carbon yarn, not only heat is generated from the carbon yarn, but also the temperature variation of the planar heating element is caused by the positional weight deviation of the relatively low content of carbon yarn, and the sense of heat is also deteriorated. have. In order to overcome this disadvantage, Korean Patent No. 0490955 and Korean Patent Publication No. 1997-0073631 disclose uniform heat generation and near-black infrared radiation function by impregnating or surface-coating a heat generating paper manufactured by a papermaking process. Was added. The heat generating paper heating module formed as described above can solve problems such as long width production impossibility, high temperature heating impossibility, durability deterioration, etc. which are disadvantages of the existing heating module, and can provide a uniform and robust heating module, but after paper processing In addition to the additional cost of processing, carbon black is not firmly bonded to the carbon yarns, and the surface of the heat-treated paper is separated, leaving room for fire and performance degradation due to external force damage.

Apart from the characteristics of the heating module, it is difficult to manufacture continuous film type planar heating element for the planar heating element that uses the heating module in the form of heat paper, and thus, no specific method or patent for continuous mass production has been proposed. Accordingly, in the case of the surface heating element to which the heating paper is applied, it is used to make discontinuous and individual module type products.

Accordingly, it is an object of the present invention to provide a conductive heating paper that is a heat generating module and a method for producing a planar heating element of a continuous film type using the same, which is economical and productive.

Another object of the present patent is to provide a planar heating element produced in the above manner.

Method for producing a planar heating element according to the present invention for achieving the above object, A) 20 to 95% by weight of paper pulp based on the total solids, 0 to 50% by weight of polyester-based phosphorus, 1 to 70 Preparing a conductive heating paper by mixing the carbon yarn of 0.1% by weight, the conductive carbon black of 0.1 to 10% by weight, and the binder resin of 1 to 10% by weight; B) coating at least one surface of the conductive heating paper using a one-component or two-component anca coating solution, and then drying at 120 to 150 ° C; c) printing and forming silver foil along both sides of one surface of the conductive heat generating paper that has passed through step B); D) attaching an electrode using a conductive adhesive on the silver foil formed in step C); And E) laminating an insulating film on both surfaces of the conductive heating paper using T-die equipment.

The planar heating element according to the present invention for achieving the above another object is 20 to 95% by weight of natural pulp, 1 to 70% by weight of carbon fiber short fiber, 0 to 50% by weight of polyester-based phosphorus, 0.1 to Conductive heat generating paper comprising 10 wt% conductive carbon black and less than 5 wt% functional filler; An anchor coating layer formed on at least one surface of the conductive heating paper; A silver foil layer formed by printing along both sides of the conductive heating paper on which the anchor coating layer is formed; An electrode adhered along an upper surface of the silver foil layer; And an insulating film laminated on both surfaces of the conductive heating paper having the electrode formed thereon.

The planar heating element according to the present invention and its manufacturing method iii) can produce a conductive heating paper having a variety of functions uniformly and stably in one process, ii) the conductive part to cover the heating part in the surface heating element through the surface treatment process of the conductive heating paper To improve the stability of the heat generating paper, iii) the best way to impart the functionality of the insulating film to be used as an insulator and iii) continuous and stable insulating finish method is presented.

The planar heating element manufactured by this method overcomes problems such as temperature nonuniformity, fire risk, and electromagnetic wave generation that existing planar heating elements have due to the uniform heating characteristics, economical production cost, suppression of defects and easy addition of functionality. Previously, it was possible to realize an innovative form of planar heating element.

Hereinafter, the planar heating element and its manufacturing method proposed in the present invention will be described in detail for each step.

A) Conductive heating paper production process: This process is to manufacture the paper-type heating module, which is the core element of the planar heating element, which can be described based on the conventional papermaking process. The conventional papermaking process refers to a process of manufacturing paper that can be used from raw materials through a stock preparation process, a paper making process, and a finishing process. The heat generating paper production process proposed in the present invention has a specificity in the undiluted solution manufacturing process, but the remaining paper forming process and finishing process is the same as a conventional papermaking process. More specifically, the stock solution manufacturing process includes a pulp process for dissolving solid pulp in water, a refiner for finely and uniformly cutting melted pulp, and reinforcing the strength of the refined fine pulp stock solution. After adding the binder and various functional additives, the mixing process (Mixing) to achieve uniform blending, and finally filtering and filtering (Screen & Cleaner) to filter out impurities before forming the paper. In the present invention, in the mixing process, carbon yarns are added in a constant ratio to impart electrical characteristics to the pulp stock solution formed through the pulper and the refiner. In addition, polyester-based phosphorus irradiation is added to enhance intelligence, heat resistance, and water repellency, and conductive carbon black particles are mixed together for more uniform heat generation and far-infrared emission.

At this time, the pulp is used as the natural pulp is selectively used within the composition range of 20 to 95% of the solid content, and the added carbon yarn is PAN-based, Pitch-based, Rayon-based short fibers used alone or in combination. The length of the short fibers is in the range of 1 to 200 mm, and the composition ratio is usually used in the range of 1 to 70% based on the solid content. If the content of the pulp is less than 20% by weight, there is a problem in the form stability of the heat generating paper, more than 95% is not preferable because of the exothermic functionality due to the lack of carbon yarn content, the carbon yarn is added to less than 1% by weight If the heat generating paper has a problem of malfunction, and when added in excess of 70% there is a problem of the shape stability of the heating paper is not preferable.

The polyester-based phosphorus yarn is used in the form of a staple fiber, and the length of the short fiber used is preferably in the range of 1 to 200 mm, and the composition ratio is preferably in the range of 0 to 50% of the total specific gravity. Even if the polyester-based phosphorus irradiation is not added, it is not a big problem in forming the planar heating element, but when it is added in excess of 50% by weight, there is a problem in form stability of the paper due to a decrease in the pulp composition, which is not preferable. The conductive carbon black is a particulate conductive carbon black having a diameter of 10 μm or less and is used within the range of 0.1 to 10%. When the conductive carbon black has a diameter exceeding 10 micrometers, it may not be strongly fixed to the heat generating paper, so that the conductive carbon black may be easily separated from the heat generating paper. When the conductive carbon black is added to less than 0.1%, the uniformity of the heat generating paper It does not help to secure the box, and the properties are significantly lower, which is not suitable as a planar heating element, and when added in excess of 10% by weight, a problem of easily detaching from the heating paper occurs, which is not preferable.

In addition, the present mixing process is also added to the binder resin used for the form stability of the paper in the normal papermaking process, the type of binder resin used is epoxy, urethane, polyvinyl alcohol (PVA) resin is used It is preferable that the composition range is used in less than 10%.

In addition to this, various functional additives may be used in the mixing process. For example, functional minerals such as ore, tourmaline, and germanium may be added to improve far-infrared heat generation characteristics, and charcoal may be used to impart negative and harmful electromagnetic waves. Materials such as activated carbon, loess, and the like may be added, and the composition thereof is preferably less than 5% of the total composition.

The raw liquid prepared in the mixing process is filtered and then sent to the headbox. As described above, the paper forming process is the same as the conventional papermaking process, and is wound in the form of paper through a head box, wiring, dehydration, and drying operations. . It is preferable to work up to 30 ~ 2,000 mm width of the formed heating paper, the winding amount is to work according to the purpose, and to check the drying process by measuring the moisture content before winding, usually work within the moisture content range of about 2 ~ 6% Proceed.

In the finishing process, quality control (rolling, slitting and rewinding) and wrapping of wound paper are carried out.The quality control items include electrical resistance, moisture content, and paper weight. have.

As described above, the heat generating paper manufacturing process proposed by the present invention has a merit that a stable, uniform and various functional heat generating module can be produced continuously and inexpensively in large quantities through a single paper making process.

1 is a plan view (a) and a cross-sectional view (b) of a conductive heat generating paper produced by the present process. The black-colored portion of the image shows the shape of the conductive heating paper containing carbon black, and the portion marked with a white background is an imaginary paper portion on the assumption that there is no carbon black for easy understanding. As can be seen from the figure, the conductive heating paper formed through the process of the present invention is pulp (1), carbon fiber (2), polyester-based phosphorus (3), functional additives (4) and carbon depending on the composition ratio of the initial The blacks 5 are evenly distributed on one sheet of paper, exhibiting a low overall resistance and uniform overall characteristics.

B) Heating paper surface treatment process: The conductive heating paper manufactured by the above-described process can be used as a heating module of the surface heating paper by itself, but it is more durable, durable, and conductive so that excellent electrical properties can be expressed. The surface treatment process of the heat generating paper is performed. Heating paper surface treatment is a treatment to improve the adhesion of the surface heating element to the insulating finishing material to make a more robust and durable product, this process is called adhesive pre-treatment (anchor coating). This process is to enhance the bonding force between the adhesive heating paper and the adhesive used when the insulating film is laminated, the important point is the selection of the anchor coating liquid and sufficient drying of the moisture contained in the conductive carbon paper.

As an anchor coating liquid, both one-component and two-component types can be used. Usually, the one-component anchor coating does not require a separate curing time, but has a disadvantage in that adhesive strength is slightly decreased. On the other hand, two-component anca coating liquid requires a separate curing time of about 1 to 2 days at a temperature of about 40 ~ 50 ℃, but after curing shows a strong adhesive strength than one-component.

Mainly used one-component anca coating liquid is an aqueous urethane-based component and composition ratio of 5 to 40% by weight of 1,2-polybutadiene, 5 to 40% by weight of epoxy resin used as a curing agent, and the remaining 90 to 20% by weight. % Is used as a solvent to mix water and methanol in an appropriate ratio depending on the drying conditions. Another one-component anca coating solution in the form of a ceramic powder Mica (Mica) is mixed in the solvent water and methanol, the composition of the mica can be used in 0.05 to 10% by weight, which is the most preferred Anka coating solution.

The two-component anca coating solution uses a polyester-based resin solution containing a polyester-based adhesive resin and ethyl acetate used as a solvent in a 1: 1 manner. Urethane prepolymer is used as a curing agent. It is diluted with ethyl acetate, which is used as a solvent, and the blending ratio of the main material, the curing agent, and the solvent is generally used at 1: 1: 8. Other two-component anca coating solutions may be used with the imine family.

In addition, when the conductive carbon paper and the finishing material are laminated together after the anchor coating on both sides of the conductive carbon paper, the resistance may become uneven due to the moisture contained in the conductive heat generating paper, or may cause a discharge phenomenon. After coating it is very important to dry the moisture completely.

Therefore, when the length of the drying furnace is short or the coating speed is high, the content of the highly volatile solvent should be increased, and if necessary, the coating speed should be lowered or passed through the drying furnace for the second drying. When performing anca coating on conductive carbon paper, it is coated by gravure roll method. It is preferable to adjust the coating amount sufficiently so that both sides of conductive carbon paper can be coated by single-side coating, and the drying conditions are 120 to about 5 ~ 10m long drying furnace. When the speed is 20m / min while heating to ~ 150 ℃, the moisture remaining in the conductive carbon paper is almost eliminated, and the resistance deviation or resistance change due to residual solvent or residual water after insulation lamination is eliminated.

C) Silver foil formation process: A process for minimizing the generation of resistance heat by suppressing a sudden change in resistance at the portion where the electrode is to be placed, and corresponds to a silver stripe process. Usually, the metal electrode used in the planar heating element is a conductor having a very low resistance. When the metal electrode is in direct contact with the conductive heating paper of the planar heating element which is a resistor, there is a possibility that an arc may occur due to overload and incomplete contact at the contact surface. As a result, a process of printing in strip form using silver powder is performed in advance to prevent the occurrence of fire. The concept of this process can be explained in FIG. 2, in which a conductive silver ink (7) obtained by mixing silver powder with a urethane-based binder and a diluent in advance is successively using a coating roll (gravure roll, 8) having an electrode shape. To print on the conductive heating paper 6. This process is the same as the conventional gravure printing process, but can be said to be different in that it uses the conductive silver ink 7. The printed conductive heating paper performs a continuous process through the drying furnace for complete drying (11).

3 is a plan view (a) and a cross-sectional view (b) of the final heat generating paper completed through the surface treatment process, the conductive heat generating paper 12 of the island is treated with an anchor coating liquid, the width on both sides of the continuous continuous heating paper Silver foil (Silver Stripe, 13, 13 'of 5 ~ 50㎜, thickness 5 ~ 50㎛ is formed by printing.

 D) Electrode Formation Process: A process of forming an electrode capable of applying power to the heat generating paper processed through the entire process, and attaching the electrode over the silver powder strip formed through the heat generating paper processing process. As a material that can be used as an electrode, a continuous thin film (Foil) of copper, aluminum, and silver having excellent conductivity can be used, and in view of durability and economy, copper foil is most preferable. At this time, the metal foil to be used may be both rolled and electrolytic foil, the thickness is 5 ~ 200um, the width is preferably 1 ~ 30mm range. One side of the electrode wire metal foil to be used is treated with a conductive adhesive to prepare an uninterrupted conduction while maintaining adhesion to the heat generating paper. At this time, as a component of the conductive adhesive, about 5 to 40% by weight of polythiophene, which is a conductive polymer, and 5 to 20% by weight of silver powder of a nanosize, and a binder resin is a heat-resistant acrylic resin of a thermosetting method. It is blended in the range of 50 to 80% by weight and coated on the copper foil electrode in the paste state. After coating the conductive adhesive, the curing is performed. The curing conditions are suitably about 2 to 3 days at about 40 ° C.

4 is a working conceptual diagram of the present process. Pressed rolls 16 and 16 'with the conductive heating paper having the surface treatment mounted on the Let-off 14 of the winder and the conductive adhesive surface of the thin film electrode 15 placed on the silver foil printed on the conductive heating paper. After pressing, the winding 17 is continuously performed. At this time, attach the left and right electrodes at the same time to balance the tension of the paper. 5 (a) is a plan view of the conductive heating paper, the electrode forming process is completed through this process, (b) is a cross-sectional view, on the silver foil (13, 13 ') printed on the surface of the conductive heating paper 12 is completed. The electrodes 18, 18 ′ are saddled.

D ') Process for imparting functionality of the film to be used as an insulating material: After the treatment of the conductive heating paper and the formation of the electrode are completed, the film to be used as the insulating material is processed. The film that can be used as the insulating film is preferably a conventional organic film, typically polypropylene (Polypropylene, PP), polyethylene (Polyethylene, PE), polyethylene terephtalate (PET), polyethylene naphthalate (Polyethylene Naphtalate, PEN), polyamide (PA), polyimide (Polyimide, PI) and the like may be mainly used. The thickness of the film is preferably 5 ~ 500um, each film type and thickness has a unique physical properties can be selectively used according to the degree of heat resistance needs, tensile strength and impact strength. The above films are referred to as basic insulating films, and only one of them can be used as a complete product, and sufficient insulation can be performed. However, in order to give a special function, the product can be produced by laminating various functional films in addition to the basic insulating film described above. Examples of the properties that the functional film can be seen include imparting flame retardancy, blocking electromagnetic waves, and improving far-infrared radiation effects.

Specifically, a flame retardant PE film is provided to impart flame retardancy, an Al-Mylar film which is electrically conductive to block electromagnetic waves, and a PVC film containing ocher and charcoal to increase far-infrared radiation efficiency is pre-laminated with the base insulating film. The lamination process is performed in a T-die manner, and FIG. 6 is a conceptual view of a conventional T-die line. The process in which the functional film is laminated to the basic insulating film is performed in a conventional T-die manner.

After placing the basic insulating film and the functional film on the first paper 19 and the second paper 22, respectively, the base insulating film is treated with an anca coating solution of the surface treatment tank 20 to improve the adhesion between the two films. The drying 21 is then carried out simultaneously. At this time, the anchor coating liquid is an anchor coating liquid used in a conventional film lamination process, a mica-based one-component type, an imine-based one-type. The basic insulating film and the functional film, which have been dried, are melt-bonded by an adhesive injected through the T-die injection port 24 and are wound 26 through a cold pressing roll 25. Annealing-Surface Treatment-Drying-Tie-Die Bonding-Compression-Wounding is performed continuously, and two or more functional films are used when using a Tandem Machine in which two or more T-die injection units are connected in series. This can be laminated at the same time. As the melt adhesive used when the two films are laminated, low density polyethylene (LDPE), polypropylene (PP), ethylene vinyl acetate (Ethylene Vinyl Acetate, EVA) may be used alone and in combination.

The functional film may be located on the outside, inside, or both of the basic insulating film, Figure 7 is an exemplary diagram in which the basic insulating film and the functional film formed through the present process, respectively, (a) is the basic insulation A cross-sectional view of a film performing only an insulation function as a cross-sectional view of the film 27, (b) is a cross-sectional view of a film in which a flame-retardant PE film 29 is laminated using a base insulating film and an adhesive 28 to impart flame retardancy. , (c) is a cross-sectional view of the film laminated with the Al-Mylar film (30, 31) to the base insulating film for the electromagnetic shielding function, (d) is treated with ocher to increase the far-infrared radiation efficiency and enhance environmental friendliness The illustrated PVC film 32 is laminated with a base insulating film. In addition, various functional films may be used in combination with the basic insulating film.

E) Finishing of heat generating paper and insulating film through T-die process: This process is to complete a continuous film type planar heating element by laminating a base insulating film or an insulating film added with functionality to the front and back of the heating paper with electrodes formed on one surface thereof. to be. The first step is to laminate the first surface of the conductive heating paper with the insulating film or the insulating film to which the functionality is added, and it is possible to first laminate the surface of the conductive heating paper to which the electrode is attached or the electrode is not attached. It is advantageous to laminate the uncoated side with the insulating film first. This is because the smoothness of the side without the electrode is better, so that laminating this side first contributes to the improvement of the smoothness of the final product. This process is also performed using the T-die equipment of FIG. In the case of one-side lamination, the primary insulating film or the insulating film to which the functionality is added is usually placed on the primary paper 19, and the secondary paper 22 after performing the anchor coating process 20 and the corona discharge treatment to improve the bonding strength with the adhesive. The heat generating paper and the melt extruder 23 and the adhesive resin melted through the tee-die (24) and the lamination, and then through the cold pressing roll 25 is wound (26). The intermediate product thus prepared is called a one-sided lamination, and FIG. 8 shows a cross-sectional view of the one-sided lamination. In FIG. 8, (a) is a cross section of a one-sided laminate in which the conductive heating paper 12 and the base insulating film 27 on which the electrodes 18 and 18 'are formed are laminated, and (b) is a flame retardant PE film 29. Is a cross-sectional illustration of a one-side lamination body in which a functional insulating film imparting a flame retardant function using a lamination) is laminated with a conductive heating paper 12.

After the one-sided lamination is finished, the one-sided lamination is placed back into the T-die's second paper 22, and then the T-die lamination once again with the insulating film of the first paper 19 or the insulating film to which the functionality is added. It will be proceeded at this time Take-up (26) the product is called two-sided lamination. The double-sided lamination has its own function as a surface heating element. However, if both sides are slitted for a clean finish, the planar heating element is completed.

In the insulating finishing process, like the film lamination process, an anca coating solution is used to improve the bonding strength between the insulating film and the adhesive. In general, an mica and an imine coating agent are mainly used. Low Density Polyethylene (LDPE), Polypropylene (PP), Ethylene Vinyl Acetate (Ethylene Vinyl Acetate) resins are mainly used. Melting temperature varies depending on the resin, but is usually operated in the range of 150 ~ 400 ℃, the thickness of the adhesive is selectively determined in the range of 1 ~ 500㎛.

9 is an illustration of a continuous process film type planar heating element finally produced through this process, (a) is a cross-sectional view of the planar heating element finished only with the basic insulating film 27, (b) flame retardant PE film 29 The cross-sectional views of the planar heating element to which the flame retardant function was imparted were respectively illustrated.

The planar heating element according to the present invention manufactured by the above process exhibits an area resistivity similar to that of the heat generating paper that is subjected to carbon black treatment through a separate impregnation process in the heat generating paper, and the variation of the area resistivity according to the position. Shows an effect of significantly lowering, the deviation of the area resistivity of the heat generating paper according to the present invention is 1.0 or less, preferably 0.5 or less, more preferably 0.3 or less. When the deviation of the area resistivity exceeds 1.0, temperature deviation for each location is generated by the resistivity deviation during the planar heating element manufacturing, and there is a risk of localized heating phenomenon, which is not suitable as the planar heating element.

In addition, in the planar heating element according to the present invention, the standard deviation of the exothermic temperature measured from all six sensors by inserting the sensor every 15 cm along the length direction of the planar heating element in units of 1 m is preferably 2 ° C. or less, and more preferably. It can be kept below 1 ° C. to achieve the highest level of uniform exotherm that can be produced commercially.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following examples.

Example 1

First, a conductive carbon heating paper was produced with the following composition.

Pulp: 60%

Polyester yarn (10mm staple from Huvis): 15%

Carbon (10mm chopped from kurea): 15%

Carbon black (EMC4 grade from Polymerits): 5%

Binder (Epoxy System): 3%

Tourmaline powder (particle size less than 5um): 2%

Conductive heating paper is coated with pulp prepared by the pulp process and refiner process of the conventional papermaking process, and then given a predetermined polyester phosphorus irradiation, carbon yarn, carbon black, binder, tourmaline powder, and the like. After performing the mixing process of about 1 hour through the head box, wiring, dehydration, drying process to produce the following conductive heating paper (SS1015).

Basis weight: 55 ± 2g / m ²

Carbon yarn content: 15 ± 0.5%

Paper width: 1010mm

Product length: 10,000m

Water content (measured immediately after production): 2.8 ± 0.2%

    <Evaluation>

In this evaluation, the area resistivity evaluation by location, which is an index for evaluating uniformity under the requirements of the heating module, was performed. For comparison, two types of conductive heating papers on the market were used. In Comparative Example 1, a product composed of pulp and carbon yarn (Central Specialty Paper, WP15-55: 15% of carbon yarn content) without carbon black was prepared. In Comparative Example 2, a paper impregnated with pulp and carbon yarn was impregnated with carbon black. The product (Sunwell, BP15AX: carbon company content 15%) was selected. Evaluation was performed by cutting the product into 1m width and measuring the area resistivity at each 10cm position.

Unit: Ωcm ² location Comparative Example 1 Comparative Example 2 Heat generating paper produced through Example 1 One 1.04 0.52 0.63 2 1.24 0.51 0.62 3 1.56 0.60 0.63 4 1.54 0.66 0.60 5 1.26 0.68 0.66 6 1.78 0.70 0.63 7 1.54 0.72 0.66 8 1.21 0.69 0.68 9 1.03 0.66 0.62 10 0.98 0.64 0.61 Average 1.32 0.64 0.63 Standard Deviation 0.27 0.07 0.03

The results indicate that the area resistivity of the heat generating paper according to the present invention was less than half as compared with the heat generating paper of Comparative Example 1, which was not treated with carbon black, which means that the high temperature and long width planar heating elements were produced even with the same carbon yarn content. It means that it is possible, and shows a similar area resistivity compared to Comparative Example 2, which means that it is possible to produce an efficient conductive heating paper in one process without a separate impregnation process, that is, the conductive heating paper of Comparative Example 1 The machining process enters. In addition, it can be seen that the area resistivity variation of each position is lower than that of Comparative Example 1 and Comparative Example 2, which means that it is possible to produce a planar heating element capable of uniform heat generation, and that the possibility of fire due to local deviation can be observed. It can be lowered.

Example 2

Using a conductive heating paper produced in Example 1, a planar heating element was produced.

As described above, the conductive heat generating paper has enhanced surface characteristics through the heat generating paper surface treatment process and the silver foil forming process. First, in order to enhance the bonding strength with an adhesive, as a one-component anca coating solution, an anca coating solution with 2% dilution of mica was prepared in a solvent of water and methanol 1: 1 composition, and the entire conductive heating paper was treated as shown in FIG. . In addition, silver foil formation was formed in the both sides of the conductive heating paper with a width of 20mm, the distance between the two silver foil was 900mm. The processed conductive heating paper was cut into 950 mm. Rolled copper foil (thickness 50um, width 15mm) was continuously laminated on the silver foil surface of 1000 m of continuous conductive heating paper treated with silver foil. The insulating film was a simple PET film (SKC SKYRoll 100um) without functional provision, and a planar heating element was manufactured through a one-side lamination and a two-side lamination process through a T-die. LDPE (SK Corporation, YUPLEN200) was used alone, and the injection thickness was 60 μm in both the upper and lower portions.

Standard Spec of the planar heating element produced by Example 2 is as follows.

Product width 1000 mm thickness 530 μm Rating AC220V, 60Hz resistance 220 Ω The tensile strength 6kgf / ㎡

A comparative evaluation was conducted between the product according to Example 2 and two planar heating elements currently on the market. The planar heating element formed by the present invention and Comparative Example 3 (USA Calorique, FLR13P10W240) and Comparative Example 4 (Xeo Energy, xeo-HT) were selected, respectively, Comparative Example 3 after printing the conductive carbon pigment in a predetermined pattern PET film It is a product in the form of insulation finishing, and the product of Comparative Example 4 is a product produced by laminating both sides of the conductive fabric with EVA coated PET film. Comparative evaluation items are product width, heat generation average temperature, power consumption, far-infrared emissivity, temperature deviation by location, bond breakdown temperature, and durability. The evaluation results are shown in Table 3.

Example 2 Comparative Example 3 Comparative Example 4 Product width (mm) 1000 600 400 Effective heat generation width (mm) 950 500 360 Rated (V / Hz) 220/60 220/60 220/60 6-point temperature (℃) 44,45,44,46,46,45 37,53,38,52,52,36 48,47,45,39,41,40 Exothermic mean temperature and standard deviation (℃) 45.0 0.89 44.7 8.43 43.3 3.82 Power consumption (W / m ² · hour) 221 217 210 Far Infrared Emissivity (%) 92.0 90.2 87.9 Bond breaking temperature (℃) Nondestructive at 100 ℃ Nondestructive at 100 ℃ 75 ℃ durability(%) -0.2 6 7

Through the evaluation results, it is possible to check the features of the planar heating element produced through the present invention. First, it can be confirmed that the product width has a product width and an effective heat generating width of more than 40% compared to other companies, which is possible because of the excellent conductivity of the carbon company, it is possible to produce a heat generating module having a relatively low resistance. This means that when the same construction area is constructed, it is possible to construct with less labor due to the characteristics of long-width products.

The product's ratings are all 220V, 60Hz for commercial use in Korea. After cutting / installing three types of planar heating elements 1m each, 6 sensors are inserted every 15cm, and the temperature is measured. The plane heating element presented showed the least deviation, and the average heating temperature was also higher than the power consumption.

Far-infrared emissivity, which is one of the features of the planar heating element, shows an excellent emissivity of about 90% in all products, but the planar heating element manufactured according to the present invention exhibits the highest emissivity of 92%, in order to increase radiation efficiency in the heating module. This is because tourmaline powder was added.

The bond breakdown temperature of the product developed through the present invention and Comparative Example 3 showed excellent characteristics of 100 ° C. or more, but in Comparative Example 4, the insulation layer was separated at 75 ° C. This is related to the heat resistance of the adhesive used. In the present invention, since the use of the adhesive having a relatively high heat resistance is easy through the melt extrusion method, it is possible to manufacture a planar heating element having a higher heat resistance than other companies.

Durability evaluation is a result of measurement using the accelerated evaluation method to confirm the resistance change after standing at 100 ℃ temperature for 24 hours, the resistance of the planar heating element produced through the present invention was almost no resistance change, the resistance of more than 5% in other products This has risen, which means a decrease in exothermic performance.

As described above, the planar heating element devised in the present invention is characterized by having a uniform heating performance and a wide heating area, it can be confirmed that the planar heating element having high far-infrared radiation efficiency and excellent durability.

Example  3

Using the conductive heating paper produced in Example 1, a planar heating element provided with functionality was produced. In the present embodiment, a planar heating element provided with flame retardancy was produced, and imparting flame retardancy is performed through a process of providing functionality of a film to be used as an insulator in the planar heating element manufacturing process proposed by the present invention. Flame retardancy is imparted through a process of laminating a flame retardant film on a base insulating film. In this embodiment, a 100 μm PET film (SKC Roll, 100 μm) was used as the base insulating film, and a flame retardant PE film was 100 μm. Polyethylene film was used, and LDPE (SK Corporation, YUPLEN200) was used as an adhesive for T-die laminating the two films. In the lamination method, the PET film is placed on the first paper sheet 19 of FIG. 6 and the flame retardant PE film is placed on the second paper sheet 22, and then the PET film is coated on the surface treatment tank 20 to improve adhesion between the two films. Treated with and used. The anca coating liquid used was a one-component mica anka liquid. The surface-treated PET film was melt-bonded by an LDPE adhesive extruded through a T-die 24 extrusion port, and wound through a cold press roll 35. 7B is a schematic diagram of the flame-retardant insulating film thus formed.

Using the flame-retardant insulating film prepared in this way, in Example 2, instead of the base insulating film was replaced with a flame-retardant insulating film, a planar heating element was produced in the same manner as in Example 2.

The flame retardant performance of the planar heating element manufactured and the planar heating element (Calorique, FLR13P10W240) presented in Comparative Example 3 were compared.

Flame retardant performance was evaluated through the measurement of horizontal flammability by a small flame as presented in KS M ISO 9772.

<Evaluation>

Planar heating element produced through Example 3 Comparative Example 3 Linear combustion speed (mm / min) Not applicable  > 40 Flame retardant burn time (seconds, average of 5) <2 > 10 Afterglow burning time (seconds, average of 5) <10 > 40 Ignition no Yes Damage length of test piece (mm) <10 > 125 Flame Retardant Grade HF-1 HBF

As can be seen from the above evaluation results, the flame-retardant planar heating element produced through the present example showed excellent flame retardant performance within the range of the HF-1 grade, which is the highest flame retardant grade suggested by KS M ISO 9772, but compared Example 3 shows the characteristics of the HBF grade that are two levels lower than the HF-1 grade.

Example  4

In this embodiment, a method of manufacturing a planar heating element to which an antistatic phenomenon is added is provided. Using the conductive heating paper produced in Example 1 and a method of manufacturing a functional insulating film from the body, the planar heating element is given a charge prevention function to the surface heating element. The production of the functional insulating film is the same as the method of Example 3, and instead of the flame-retardant PE film, the conductive Al-Mylar film is laminated with the PET film to generate a planar heating element. The resulting antistatic phenomenon functional insulating film is shown in Fig. 7C. At this time, the Al-Mylar film and PET film lamination method is the same as the lamination method of Example 3, using the LDPE adhesive agent also produced a planar heating element is provided with an antistatic property. The method of manufacturing the planar heating element was the same as that of Example 1, and the comparative evaluation was evaluated together with Comparative Example 3 (Calorique, FLR13P10W240, USA), and the evaluation method used the induction voltage measuring method presented in KS60335-1. An aluminum plate having a width of 20 cm and a length of 10 cm was placed on a planar heating element, and the induced voltage was confirmed by measuring voltage with the earth. The planar heating element produced in this example was evaluated by connecting the conductive surface of the Al-Mylar surface to ground. The planar heating element was operated at 220V, and the insulation material was evaluated without adding an insulation material between the planar heating element and the aluminum plate.

<Evaluation>

Planar heating element produced through Example 4 Comparative Example 3 Induction voltage (V) <1 128

As can be seen from the above results, the embodiment of the present invention was able to confirm that it is possible to manufacture a planar heating element having an electrostatic induction prevention function.

1 is a plan view and a cross-sectional view of a conductive heating paper produced according to the present invention.

2 is a conceptual diagram of a facility for the silver stripe process of the present invention.

3 is a plan view and a cross-sectional view of a conductive heating paper subjected to a surface treatment process according to the present invention.

4 is a conceptual diagram of a facility for forming an electrode of the present invention.

5 is a plan view and a cross-sectional view of a conductive heat generating paper has completed the electrode forming process according to the present invention.

6 is a conceptual diagram of a T-die facility for the functional film lamination process and the insulating film finishing process according to the present invention.

7 is a cross-sectional view of an insulating film laminated with a basic insulating film and a functional film according to the present invention.

8 is a cross-sectional view of a one-sided laminated body formed in accordance with the present invention.

9 is a cross-sectional view of a film type planar heating element according to the present invention.

※ Code explanation about main parts of drawing

1: pulp 2: carbon yarn

3: polyester-based phosphorus 4: functional additive

5: carbon black 6: conductive heating paper injection

7: conductive silver ink bath 8: coating roll

9: Back Roll 10: Doctor Knife

11: Progress of conductive heating paper after silver printing, direction of drying furnace

12: conductive heat generating paper with surface treatment

13 and 13 ': silver stripe formed on the conductive heating paper

14: LET-OFF

15: metal foil electrode loosening (Let-Off)

16, 16 ': pressing roll

17: Take-up of conductive heating paper with electrode

18, 18 ': electrode seated on silver foil printed on conductive heating paper

19: Paper 1 (Unwinding) Let-Off 20: Surface treatment solution tank

21: drying furnace 22: 2nd paper feed (Let-Off)

23: melt extrusion apparatus 24: T-die injection port

25: compression cooling roll 26: T-die take-up (Take-Up)

27: basic insulating film 28: adhesive for film lamination

29: flame retardant PE film

30: Mylar layer of Al-Mylar film

31: aluminum layer of Al-Mylar film

32: ocher added PVC functional film

Claims (23)

A) forming a conductive heating paper by a papermaking process including a stock preparation process, a paper making process, and a finishing process, wherein the stock solution manufacturing process is based on total solids, 20 to 95% by weight of paper pulp; 0-50% by weight of polyester-based phosphorus irradiation; 1 to 70% by weight of carbon yarn in which PAN, Pitch type, Rayon type short fibers are used alone or in combination; Mixing 0.1 to 10 weight percent conductive carbon black, and 1 to 10 weight percent binder resin; B) coating one or both sides of the conductive heating paper formed from step A) using a one-component or two-component anca coating solution, and then drying at 120 to 150 ° C; C) printing and forming silver foil along both sides of one surface of the conductive heating paper, which has undergone the step B); D) attaching an electrode using a conductive adhesive on the silver foil formed in step C); And E) A method of manufacturing a continuous film type planar heating element comprising the step of laminating an insulating film on both surfaces of the conductive heating paper by using a T-die facility. delete The method of claim 1, wherein the conductive carbon black of step A) has a diameter of 10 micrometers or less. The method of claim 1, wherein the binder resin of step A) is an epoxy-based, urethane-based, or polyvinyl alcohol-based resin. The method of claim 1, wherein in step A), a functional additive selected from the group consisting of sorghum, tourmaline, germanium, charcoal, activated carbon, and loess is added in an amount of less than 5% by weight. According to claim 1, wherein the one-component anca coating solution of step B) comprises 5 to 40% by weight of 1,2-polybutadiene, 5 to 40% by weight epoxy resin, and 90 to 20% by weight alcohol solvent The planar heating element manufacturing method characterized by the above-mentioned. The method according to claim 1, wherein the one-component anca coating solution of step B) is 0.05 to 10% by weight of mica mixed with a residual amount of alcohol solvent. The method of claim 1, wherein the two-component anca coating solution of step B) is a main material: a curing agent: a solvent is mixed in a ratio of 1: 1: 8, the main material is a polyester-based adhesive resin and the solvent is 1: 1 Method for producing a planar heating element, characterized in that the mixed solution. According to claim 1, wherein the conductive adhesive of step D) is 5 to 40% by weight of polythiophene (polythiophene) conductive polymer, 5 to 20% by weight of silver powder, 50 to 80% by weight of acrylic resin and A method for producing a planar heating element, which is prepared by blending. The method of claim 1, wherein the insulating film of step E), E1) applying an anchor coating liquid to the surface of the basic insulating film and drying it; E2) preparing a functional film having flame retardancy, conductivity or far infrared radiation; E3) forming a planar heating element, comprising the step of laminating while imparting a melt adhesive between the dried basic insulating film and the functional film. The method of claim 10, wherein the basic insulating film is polypropylene, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polyamide, or polyimide having a thickness of 5 to 500 µm. delete 20 to 95% by weight of natural pulp, which is formed by a papermaking process including a Stock Preparation Process, a Paper Making Process, and a Finishing Process; PAN, Pitch-based, Rayon-based short fibers of 1 to 70% by weight of carbon yarn short fibers used alone or mixed; 0-50% by weight of polyester-based phosphorus irradiation; 0.1-10% by weight of conductive carbon black; And less than 10% by weight of binder resin; An anchor coating layer formed on one surface or both surfaces of the conductive heating paper; A silver foil layer formed by printing along both sides of the conductive heating paper on which the anchor coating layer is formed; An electrode adhered along an upper surface of the silver foil layer; And And an insulating film laminated on both surfaces of the conductive heating sheet having the electrodes formed thereon. delete delete delete delete delete delete delete delete delete delete

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