KR101168906B1 - Constant heater using ptc-positive temperature coefficient constant heater-ink polymer - Google Patents

Abstract

PURPOSE: A constant temperature heating device using PTC(Positive Temperature Coefficient) heating ink is provided to improve the stability of quality by minimizing the variation of an initial resistance after heating. CONSTITUTION: A pair of PET films(110a,110b) has heat resistance and insulation properties. A pair of metal electrodes(120a,120b) are attached to the edge of a bottom PET film with adhesives(123). An ester group nonwoven fabric(130) is received in the bottom PET film to prevent the movement of the pair of metal electrodes. The ester group nonwoven fabric prevents a crack in a boundary between the bottom PET film and the pair of the metal electrodes. A dry coated film is formed between the metal electrode and the ester group nonwoven fabric with polymer PCT heating ink(140).

Description

Constant Heater Using PTC-Positive Temperature Coefficient Constant Heater-ink Polymer}

The present invention relates to a constant temperature heating element of a film type for heating, and more particularly, to a constant temperature heating element using a polymer PTC constant temperature heating ink having a self temperature control characteristic.

There is an urgent need to develop and apply energy-saving heating heating materials and heating elements using them, due to the depletion of energy resources such as fossil fuels.Wire heaters are currently used for heating in general houses and industries. Heater (Film Heater) is a situation that is difficult to secure the safety and reliability of the product due to the disadvantages of the heating material applied to the manufacturing of each heating element.

The linear heating elements made of heating materials such as nichrome and iron chromium are relatively low in thermal efficiency due to the linear heating and consume relatively high power, and the entire heating element is not heated due to open circuit in one place due to series connection. There is difficulty in repairing, abnormal heat generation such as local overheating such as heat collection, high risk of damaging heating element and fire, and lack of product safety.

In addition, the planar heating element manufactured by the carbon paste printing process uses conductive particles such as carbon black or graphite as a resistive heating source, and thus the resistance value changes due to repeated use, and the heating element due to abnormal heating such as local overheating such as heat collection. There is a high risk of damage and fire and there is a lack of product safety.

In particular, the path of occurrence of damage to the heating element and the occurrence of fire due to abnormal heating such as local overheating such as heat collection, which is the biggest problem of the linear heating element and the planar heating element, is as follows. That is, when the temperature of the heat accumulator rises due to abnormal phenomenon (heat insulation, heat storage, overheating), damage occurs to heating elements and finishes such as local overheating, which causes fire.

Currently, the linear heating element and the planar heating element that are used for heating are equipped with a temperature control system such as a separate overheat prevention sensor in order to remove the risk of abnormal heating phenomenon of the heating element.

However, it is not enough to overcome the risk of fire damage and heating element caused by partial high temperature such as local overheating due to heat collection.

In addition, with the development of automobile industry and various electronic industries, the use and quantity of high-temperature PTC (Positive Temperature Coefficient), a BaTiO _3- based semiconductor device that can be used at low voltage, is increasing day by day, but most depend on imports. It is true.

Polymer PTC acts as a conductor (low resistance state) at room temperature and in normal state because conductive material is dispersed in crystalline polymer resin, but in abnormal state such as overload or overheating, it is amorphous by thermal melting and micro-volume expansion of crystalline polymer. As the lattice distance between the polymer resin and the conductive material is separated, a sudden spontaneous transition occurs in a non-conductive (high resistance state) range above a certain temperature, and the current is applied to the electronic circuit. If the abnormal condition is removed and the temperature of the polymer PTC is lowered, it can return to the original low resistance value and the circuit can be operated normally.

By applying the polymer PTC as a heating material by using the above characteristics, it can generate heat in a short time by flowing a current with low resistance at low temperature, and the resistance rises rapidly in a specific temperature range (current cutoff rate of 15 to 30%) The balance of Joule's Heat and the heat dissipated by the electric energy supplied to the device achieves the equilibrium heating state of low power consumption characteristics (70 ~ 85% of the existing heating elements), and the problem of existing linear heating elements and planar heating elements. It can overcome the risk of fire damage and heating element caused by abnormal heating such as local overheating such as phosphorus heat collection.

However, in order to satisfy the PTC characteristics, the PTC characteristics are improved by controlling the amount of dopant, which is an intentionally added impurity, in order to widen the firing temperature during the manufacture of the PTC device and to change the electrical conductivity of the semiconductor. It is important to solve various problems.

On the other hand, according to Patent No. 10-1128033 (2012.03.12) registered by the applicant, a method of manufacturing a plastic film carbon heating element of the front coating method using a CNT heating ink has been proposed.

However, the registered patent technology can greatly improve the adhesive strength between the metal electrode and the plastic (PET) film and the metal electrode and the heating material (carbon mixture) constituting the carbon heating element to increase the stability and durability of the product as a whole to extend the life of the product On the other hand, the carbon heating element itself does not have the magnetic temperature control characteristic of temperature control.

Accordingly, the present invention proposes a completely new constant temperature heating element in which a multi-walled carbon nanotube (MWNT), which is a conductive fine particle, is fused to a semiconductor material having positive temperature coefficient characteristics by applying and improving a registered patent.

Therefore, the present invention is designed to overcome the above-mentioned problems, and more specifically, a positive temperature coefficient (PTC) circuit protection device manufacturing technology and multi-walled carbon nanotubes (MWNT) It is an object of the present invention to provide a constant temperature heating element using a high molecular weight PTC constant temperature heating ink which has a flexible nano PTC constant temperature heating element having a self-temperature control and low power consumption characteristics using a polymer PTC constant temperature heating ink fused with a dispersing technology.

According to a feature of the present invention for achieving the above object, in a constant temperature heating element using a polymer PTC constant temperature heating ink, the constant temperature heating element is manufactured in a constant size with a thin surface and heat resistance and insulation, but the phase of the constant temperature heating element A pair of PET films 110a and 110b serving as lower covers; The modified urethane-based adhesive 121 and TDI containing an ester compound by selecting any one of Ni, Ag, Sn, and Zn having a matte treatment and a plated thin film on the edge of the lower PET film 110b. A pair of metal electrodes 120a and 120b attached by the adhesive 123 to which the (Toluene Diisocianate) -based curing agent 122 is combined; It is seated on the front surface of the lower PET film (110b) to prevent cracks generated at the boundary between the lower PET film (110b) and the pair of metal electrodes (120a, 120b) and to prevent the flow of the pair of metal electrodes. Ester-based nonwoven fabric 130 and; PTC device 141, which is a semiconductor material having a positive temperature coefficient characteristic so as to form a dry coating film between the metal electrodes (120a, 120b) and the ester-based nonwoven fabric 130 to enhance adhesion and have conductivity and magnetic temperature control characteristics ) Polymer PTC constant temperature heating ink in which conductive polymer composition fused with multi-walled carbon nanotube (MWCNT or MWNT, Multi-walled Carbon Nanotube, 142), TDI curing agent 122 and peroxide crosslinking agent It provides a constant temperature heating element using a polymer PTC constant temperature heating ink, characterized in that 140).

According to one embodiment of the present invention, the polymer PTC constant temperature heating ink, after the bead mill (Bead Mill) dispersing process is uniformly stirred with a dissolver (dissolver), but the mill base (Mill Base) of the polymer PTC constant temperature heating ink 10g, 8.20wt% of TDI (Toluene Diisocianate) crosslinking agent for polyester binder, and 100g, 81.97wt% of composition, 2g of DCP (Dicumyl Peroxide), 1.64wt% and 10g of xylene, 8.20 wt% is characterized in that the input.

According to one embodiment of the invention, the constant temperature heating element, the sample size W500mm × L250mm × T0.075mm, the initial resistance change rate (Rate of change) when applying AC 220V is -3.45%, Resistance before heating (Resistance before heating) Is 1449 kW, and resistance after heating is 1399 kW.

According to one embodiment of the present invention, the trip current for the constant temperature heating element (Trip Current), the heat transfer area (Heating Area) is 0.135M ² days when AC 220V in order not to limit the construction area of the PTC constant temperature heating element time At 0.12A, 2.16M ² At 1.92A and 33M ² , a trip current of 29.33A is maintained.

According to an embodiment of the present invention, the power consumption for the constant temperature heating element (Power Consumption), the sample size of the constant temperature heating element W500mm * L250mm * T0.075mm, AC 220V, active area (Active Area) 0.125M ² , heating element When the ambient temperature (Ambient Temp.) 17 ℃ and the heating element surface temperature (Heating Temp.) Is heated to 40 ℃, it is characterized in that 40W.

According to one embodiment of the present invention, the acceleration and the chronological change of the constant temperature heating element, after installing the sample size W500mm × L250mm × T0.075mm of the constant temperature heating element in an oven, the power to the PTC constant temperature heating element at the oven temperature of 80 ℃ By applying the initial resistance for constant temperature heating and abnormal overheating is characterized in that the room temperature 18 ℃, 1.364kΩ.

According to one embodiment of the present invention, the resistance change rate for the constant temperature heating element, after the sample size W500mm × L250mm × T0.075mm of the constant temperature heating element is installed in the oven, the oven temperature is 20 ℃ to 150 ℃ every 10 ℃ Each time the temperature rises, the initial resistance according to the resistance change of the PTC constant temperature heating element is 18 ° C. and 1.283 kΩ.

Constant temperature heating element using the polymeric PTC constant temperature heating ink according to a preferred embodiment of the present invention can be expected the following effects.

According to the present invention, by constructing a high-molecular PTC constant temperature heating element having a self-temperature control characteristic in which a semiconductor material having a positive temperature coefficient characteristics and a multi-wall carbon nanotube dispersion technology is fused,

(1) The thermostatic heating element to which the high-molecular weight PTC thermostatic ink with high dispersion of multi-walled carbon nanotubes is applied removes the risk of damage to the heating element and the fire caused by the self-temperature control characteristics, and the low power consumption of 70-85% of the existing heating element. Has

(2) The application of MWCNT (or MWNT) solves the problems caused by the high content filling of existing carbon-based conductive particles (carbon black and graphite) to improve flexibility of the heating element, and generates heat due to repeated use of the heating element. After minimizing the change in the initial resistance value, the heat generation characteristics are more uniformly formed, thereby ensuring the quality stability and reliability of the product.

1 is a view for schematically explaining a magnetic temperature control characteristic of a PTC device;
Figure 2 is a view showing the configuration of a constant temperature heating element for a constant temperature heating element using a high temperature PTC PTC heating polymer according to a preferred embodiment of the present invention
Figure 3 is a graphic showing the resistance variation (Resistance Variation) as a result of the evaluation of the comparative characteristics test between the prototype of the constant temperature heating element and the other products for the constant temperature heating element using the polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention
Figure 4 is a graphic showing the trip current (Trip Current) as a result of the evaluation of the comparative characteristics test between the prototype of the constant temperature heating element and the other products for the constant temperature heating element using the polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention
Figure 5 is a graphic showing the power consumption (PowerConsumption) that is the result of the evaluation of the comparative characteristics test of the prototype of the constant temperature heating element and the other products for the constant temperature heating element using the polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention
6 is an acceleration test and an aging test (Acceleration Test & Aging Test) that is a result of evaluating a comparative characteristic test of a prototype of a constant temperature heating element and another product for a constant temperature heating element using a polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention graphic
Figure 7 is a graphic showing the resistance change test (RT Test) according to the temperature of the thermothermal element prototype for the constant temperature heating element using the polymeric PTC constant temperature heating ink according to a preferred embodiment of the present invention

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components throughout the drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

First, the method for preparing a polymer PTC constant temperature heating ink (paste) for a constant temperature heating element using the polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention will be described in detail.

[1] method for producing binders for polymeric PTC constant temperature heating ink (paste)

The manufacture of the binder for a polymeric PTC thermosetting ink (paste) is a polyester-based plastic film (PET film) or a non-woven fabric which is a printing (coating) substrate of a thermosetting ink and a polyester binder and a constant temperature for imparting adhesive force and printability. It consists of a mixture of polyolefin (Polyolefine) -based binder composed of a crystalline polymer for imparting PTC properties in the exothermic ink, it is prepared by mechanical stirring in the reactor in the composition of Table 1.

The polyester binder manufacturing method for ① of Table 1 is as follows.

The polyester binder is a polyester binder mainly composed of a polyester resin having excellent compatibility and adhesion with a polyester plastic film (PET film) or a nonwoven fabric and having good chemical resistance, flexibility, and printability (workability). Is prepared by mechanical stirring in a reactor capable of heating with the composition of Table 2.

The polyolefin-based binder manufacturing method for ② of Table 1 is as follows.

Polyolefin binder is a polyolefin resin which is a crystalline polymer in order to impart PTC characteristics. Polyethylene (PE, Polyethylene), Polypropylene (PP, Polypropylene) and Ethylene Vinyl Acetate (EVA) It is prepared by mechanical stirring in a reactor capable of heating with a composition of 3.

[2] method for preparing mill base composition of polymeric PTC thermothermal ink (paste)

The mixed composition of conductive particulates such as multi-walled carbon nanotubes (MWCNT or MWNT, Multi-walled Carbon Nanotube) and binders for high-temperature PTC heating paste (paste) is shown in Table 4. (Mill Base) The composition is formed and has a wetting time to the binder of the conductive fine particles such as MWCNT or MWNT for 24 hours to 48 hours at room temperature.

[3] Wet-Grinding Bead Milling Method of Polymer PTC Constant Temperature Heating Ink (Paste) Mill Base Composition

The composition mixed with the mill base as shown in Table 4. The ceramic beads of 50 to 80% of the volume of the container and about 10 discs attached to the rotating shaft are mounted in the container. It is sent to the inlet of the vessel by the feed pump of the bead mill.

The sent mill base is a bead and a multi-walled carbon nanotube (MWNT) between the bead and the mill base protruding toward the inner wall of the container by the centrifugal force caused by the rotation of the disc (500-800 m / min circumference). As the pigment is dispersed by the strong shear force due to the difference in the flow rate of the conductive particles, the beads and the mill base are separated by the separation mechanism (Screen or Gap) of the container, so that only the mill base is discharged to the outside and is taken to the take away pump. Suction is sent to the finish tank.

Through this process, the pulverization of releasing aggregates and aggregates of conductive fine particles such as multi-walled carbon nanotubes (MWNT) to the state of primary particles by mechanical separation, and the pulverized particles are transferred to the liquid binder so that each particle is stable. It has a process to be distributed to.

[4] Mill Base Adjustment of Polymer PTC Constant Temperature Heating Ink (Paste)

The composition for the adjustment of the polymeric PTC constant temperature heating ink (paste) millbase composition and the cross linking of each binder system after the bead mill dispersion process are shown in Table 5.

The conditions for the best (Let Down) is a mechanical condition, while slowly stirring the mill base strongly (mechanically, a vehicle, a crosslinking agent, etc.) for adjustment, the temperature between the developer and the mill base for adjustment Avoid excessive differences in viscosity (or either one), and make sure that the compositional agent does not have a large difference in composition from the millbase, and that the weaker solvent is distributed over the solvent-rich colorant when using mixed solvents. (Except for millbases where the binder exceeds the dilution limit).

Hereinafter, a method for manufacturing a polymeric PTC thermothermal ink (paste) according to a preferred embodiment of the present invention will be described in detail.

<Example: 1>

(1) Preparation of polyester binder for polymer PTC constant temperature heating ink (paste)

First, 50 g of polyvinyl chloride, 5.03 wt% and 50 g of polyvinyl acetate, 5.03 wt% were stirred while heating to 70 ° C. until completely dissolved in 280 g of acetone and 28.14 wt%. .

Next, 300 g of polyester and 30.15 wt% were added to 240 g of toluene, 24.12 wt% of mixed solvent of 60 g and 6.03 wt% of methyl ethyl ketone, and then maintained at 50 ° C. completely. Stir until dissolved.

Then, 380 g of a solution of polyvinyl chloride and polyvinyl acetate dissolved in acetone, 5 g, antifoaming agent, 0.5 wt%, and 10 g, 1.0 wt% of leveling agent were added and mixed until completely mixed. Agitated to prepare a polyester binder for polymer PTC constant temperature heating ink (paste). This is shown in Table 6.

<Example: 2>

(2) Preparation of polyolefin binder for polymer PTC constant temperature heating ink (paste)

First, 30 g of polyethylene, 2.84 wt%, 10 g of polypropylene, 0.95 wt%, 100 g of ethylene-vinyl acetate copolymer, 9.48 wt%, 900 g of xylene, 85.31 wt% It is stirred while heating to 100 ° C in%, completely dissolved and cooled.

Next, 5 g, 0.47 wt% of an antifoaming agent and 10 g, 0.95 wt% of a leveling agent were added thereto, and stirred until completely mixed to prepare a polyolefin-based binder for a polymer PTC constant temperature heating ink (paste). This is shown in Table 7.

<Example: 3>

Hereinafter, a method for preparing a binder for polymer PTC constant temperature heating ink (paste) through the preparation of the above-described (1) polyester binder and (2) polyolefin-based binder according to an embodiment of the present invention will be described.

150g, 12.17wt% of the polyester binder prepared in Table 6. 1050g, 85.16wt% and 20g, 1.62wt% and 7g, 0.57wt% of the polyolefin-based binder prepared in Table 7. 6 g and 0.49 wt% were mixed and stirred until a uniform solution was prepared, thereby preparing a binder for polymer PTC thermothermal ink (paste). This is shown in Table 8.

<Example: 4>

Hereinafter, the mill base composition of the polymeric PTC constant temperature heating ink (paste) according to an embodiment of the present invention will be described.

900g, 88.06wt% of binder for polymer PTC heating ink (paste), 10g, 0.98wt% of multi-wall carbon nanotube, 102g of acetylene carbon black, 9.98wt% of xylene (Xylene) 10g, 0.98wt% Mill Base composition by stirring with a dissolver and uniformly mixed with a binder of conductive particles such as multi-walled carbon nanotubes (MWNT) for 24 hours to 48 hours By having a wetting time of the polymer PTC constant temperature heating ink (paste) to make a Mill Base (Mill Base) composition. This is shown in Table 9.

<Example: 5>

Hereinafter, the dispersion process of the mill base composition of the polymeric PTC constant temperature heating ink according to an embodiment of the present invention will be described.

First, the Mill Base composition of Table 9. The bead mill is equipped with a ceramic bead of 70% of the container volume and about 10 discs attached to the rotating shaft inside the container. It is sent to the inlet of the vessel by the feed pump of the mill.

Next, the sent Mill Base composition, the bead (Bill) and Mill Base (Mill Base) by the centrifugal force by the rotation of the disc (circumference 700 ± 70m / min) collide with the inner wall of the container, While the pigment is dispersed with strong shear force due to the difference in the flow rate of conductive particles such as beads and multi-walled carbon nanotubes (MWNT), the beads are separated by a screen or a gap of the container. Mill base is separated and only mill base is leaked to outside and suctioned by take away pump and sent to finish tank.

Through this process, the pulverization of releasing aggregates and aggregates of conductive fine particles such as multi-walled carbon nanotubes (MWNT) to the state of primary particles by mechanical separation, and the pulverized particles move to a liquid binder, thereby making each particle stable. It has a process to be distributed to.

<Example: 6>

Hereinafter, a description will be given of a method for producing a polymeric PTC constant temperature heating ink 140 for a constant temperature heating element using the polymeric PTC constant temperature heating ink according to a preferred embodiment of the present invention through the above-described <Example 1> to <Example 5> do.

10 g, 8.20 wt% of a TDI (toluene diisocianate) crosslinking agent for polyester binders and a crosslinking agent for a polyolefin binder in 100 g, 81.97 wt% of the millbase composition of the polymer PTC constant temperature heating ink which has undergone the bead mill dispersion process DCP (Dicumyl Peroxide) 2g, 1.64wt% and xylene (10g), 8.20wt% was added to uniformly stirred with a resolver (dissolver) to prepare a polymer PTC constant temperature heating ink (paste). This is shown in Table 10.

Hereinafter, referring to FIGS. 1 to 7, a constant temperature heating element using a polymer PTC constant temperature heating ink according to a preferred embodiment of the present invention will be described in detail.

First, with reference to FIG. 1, the magnetic temperature control characteristic of the polymeric PTC constant temperature heating element is demonstrated.

The polymeric PTC constant temperature heating element is based on the overall internal energy balance represented by the following formula (1).

mCp (ΔT / Δt) = I ² RU (T-Ta) (1)

Where I: current, R: PTC resistance, Δt: elapsed time, m: PTC mass, Cp: heat capacity, ΔT: PTC temperature change, T: PTC temperature, Ta: ambient temperature, U: heat transfer coefficient.

According to Equation (1), the amount of heat (I ² R) generated inside the device is equal to the amount represented by the mCp (ΔT / Δt) term except for the heat amount U (T-Ta) radiated to the outside air. The temperature of is raised. For the sake of simplicity, assuming that there is no temperature change in the outside air, the term (ΔT / Δt) becomes 0 and accordingly, Equation (1) can be expressed as follows.

I ² R = U (T-Ta) (2)

Therefore, in the general state, the self-heating of the PTC constant temperature heating element is radiated to the outside, and the temperature becomes relatively low. When the amount of current flowing in is gradually increased, the calorific value of the PTC constant temperature heating element is increased and the temperature thereof is also increased.

However, if the amount of heat generated is not very large, all of the heat is dissipated so that the inflow of current increases or the temperature rises to a point where a sudden increase in resistance occurs. After this state, a slight increase in inrush current or external temperature leads to a rapid change in resistance.

PTC constant temperature heating element is also called trip element. This rapid increase in resistance minimizes the amount of current flowing into the circuit and protects the device's circuit from overcurrent. If the PTC heating element is tripped and the power supplied is large enough, it will remain tripped, but if the voltage supplied to the device or the incoming power is reduced, the PTC heating element will return to normal operation.

Therefore, the core technical construction means of the present invention, a pair of PET (Polyethylene Terephthalate) film (110a, 110b), a pair of metal electrodes (120a, 120b), ester nonwoven fabric 130 and a high-temperature PTC constant temperature heating ink ( 140).

Referring to Figure 2, a pair of polyethylene terephthalate (PET) film (110a, 110b) is a means that serves as a top and bottom cover of the constant temperature heating element, a thin surface PET film means having heat resistance and insulation has a certain standard Have PET is polyethylene terephtalate and is one of the plastic molding materials. PET molding materials reinforced with glass fibers have good physical properties compared to thermosetting resins, and are used in electronic parts, automotive electronic parts, hot air balloons, and the like, and non-reinforced molding materials are frequently used for blow molding. In addition, PET is non-toxic, odorless, high transparency, and is currently used as a food container. In terms of characteristics, the heat resistance is 265 ° C., the heat deformation is 240 ° C., and the continuous heat is 150 ° C. The electrical properties of ordinary PET products are the same as those of other polyesters, but specialty PET products are resistant to electric arcs and cracks. It has good chemical resistance, dimensional stability and weather resistance and excellent stress cracking resistance.

Referring to FIG. 2, the pair of metal electrodes 120a and 120b are electrode means to which power is applied to generate heat of the film-type planar heating element for heating, and an ester-based (Ester) at the edge of the lower PET film 110b. The modified urethane-based adhesive 121 containing the compound and the toluene diisocianate (TDI) -based curing agent 122 are attached by the combined adhesive.

Here, the modified urethane-based adhesive 121 and the TDI (Toluene Diisocianate) -based curing agent 122 containing the ester compound according to the embodiment of the present invention are manufactured in an 80:20 to 90: 10% blending composition ratio of the lower PET film. Apply on 110b. The reason is that the lower PET film is an ester-based nonwoven fabric 130, which is a substrate on which the power supply metal electrodes 120a and 120b and the polymer PTC constant temperature heat ink 140 are applied. In addition to the adhesive firmly fixed on the (110b) and the planar heating element of the heating film type is abnormally operated, that is, overheated to 80 ~ 120 ℃ by heat (or heat storage) and a pair of metal electrodes (120a, 120b) and This is to prevent the de-lamination effect of the ester-based nonwoven fabric 130 being adhesively fixed to each other in the form of a thin plate by an adhesive so as not to form a single layer but split into thin pieces.

In addition, the surfaces of the pair of metal electrodes 120a and 120b may be matt processed and plated thin to prevent oxidation. In addition, any one of the pair of metal electrodes is selected from Ni, Ag, Sn, and Zn.

Referring to Figure 2, the ester-based nonwoven fabric 130, to prevent the cracks generated at the boundary between the lower PET film (110b) and the metal electrode (120a, 120b) and to prevent the flow of a pair of metal electrode By means, it is seated on the entire surface (or front) of the lower PET film 110b.

The reason for seating the ester-based nonwoven fabric 130 according to an embodiment of the present invention, the polymer PTC constant temperature heating without using the ester-based nonwoven fabric 130 on a pair of metal electrodes (120a, 120b) insulated with an adhesive When the ink 140 is directly applied, cracks (or cracks) are generated, which causes an unexpected big fire risk such as spark generation when power is applied or when the planar heating element of the film type for heating is generated. As a result, the ester-based nonwoven fabric 130 serves as a support for stably maintaining a dry coating film of the polymer PTC constant temperature heating ink 140.

Referring to FIG. 2, the polymer PTC constant temperature heating ink 140 forms a dry coating film between the pair of metal electrodes 120a and 120b and the ester nonwoven fabric 130 to enhance adhesion and control conductivity and magnetic temperature. As a conductive polymer composition having a characteristic, a conductive polymer composition in which a PTC device 141, which is a semiconductor material having positive temperature coefficient characteristics, and a multi-walled carbon nanotube (MWCNT or MWNT, Multi-walled Carbon Nanotube, 142) are fused together And a TDI curing agent 143 and a Peroxide crosslinking agent.

Herein, the PTC device 141 is an electronic component material made by highly dispersing conductive fine particles WMCNT (semiconductor particles) having high temperature coefficient characteristics and generates heat when electrical energy is applied. It is a kind of polymer PCT constant temperature heating that has a self-temperature control function that generates heat by raising the electric resistance to a certain level and suppressing the flow of electric current by raising the electric resistance, and when the temperature drops, the electric resistance is lowered to improve the flow of current. Ink.

In addition, the multi-walled carbon nanotube 142 has a structure in which a six-membered ring network (or a drawing sheet) made of carbon is arranged coaxially. When the carbon nanotubes are single layer or single wall, they are called single-wall carbon nanotubes (SWCNT), and when multi-walled or multi-walled carbon nanotubes are called multi-wall carbon nanotubes (MWCNT). While single-wall carbon nanotubes (SWCNTs) are being used as nanoscale devices, research and development on their electrical properties are in full swing, while multi-walled carbon nanotubes (MWCNTs) are called carbon nanofibers from a fiber engineering perspective. As a fibrous additive, there is a great modification effect by compounding with dissimilar materials. This is because MWCNT is more economical than SWCNT, and it is about half the weight of aluminum and its tensile strength in the fiber direction surpasses that of diamond, so it is applied to a wide range of applications by utilizing the characteristics of light weight, toughness, high conductivity, and high thermal conductivity. This is possible.

In addition, the TDI-based curing agent 143 is to prevent the thermal damage of the heating film-type constant temperature heating element due to the increased heat resistance between the adhesive and the polymer PTC constant temperature heating ink 140.

On the other hand, according to the manufacturing process of the CNT heating ink of the Republic of Korea Patent No. 10-1128033 (2012.03.12) proposed by the applicant, 600 g of ethyl acetate (Ethyl Acetate) in 253g, 25.3wt% of the ester-based binder 60 wt% of carbon nanotubes, 30 g of dispersant, 3 g of antifoam, 1 g of 0.1 wt%, 3 g of leveling agent, 3 g of 0.3 wt%, 3 g of anti-settling agent, and 0.3 wt% of the carbon nanotube were added into the solution. After the addition of 10wt%, uniformly mixed with a dissolver to prepare a Mill Base composition of the CNT heating ink, and bead milling applied to the dispersion of the mill base composition of the polymeric PTC constant temperature heating ink (paste) Using the same process to prepare a CNT exothermic ink as shown in Table 11.

However, the CNT heating ink as shown in Table 11 improves the electrical properties of the film-type carbon heating element for heating as well as improves the product quality of the heating film system, whereas, as in the embodiment of the present invention, Flexible Nano PTC constant temperature heating element with low power consumption and self temperature control characteristics by highly dispersing and fusing conductive particulate multi-walled carbon nanotubes (MWCNT or MWNT, Multi-walled Carbon Nanotube) in semiconductor materials with temperature coefficient characteristics There is a remarkable difference in that it has a constant temperature heating element).

Hereinafter, a comparative evaluation result of a characteristic test between a prototype of a constant temperature heating element using a PTC constant temperature heating ink according to an embodiment of the present invention and another product will be described.

First, the results of testing the resistance change relationship of the PTC heating element (or the heating element) according to an embodiment of the present invention are shown in Table 12. and FIG.

As shown in Table 12. and FIG. 3, the most important item for evaluating the PTC characteristics and effectiveness of the PTC heating element (or the heating element) according to the embodiment of the present invention is a comparative test subject of the present invention (Korea NDT PTC). Is a general front coating type heating element manufactured by Japanese company A's PTC constant temperature heating element (front coating type) and CNT heating ink invented by a patent registered by the present applicant.

This shows the return characteristics to initial resistance (resistance before heat generation) after heating and affects the quality stability (heating rate, heating temperature, power consumption) of the product.

Therefore, the sample size of the PTC constant temperature heating element (or the constant temperature heating element) according to the embodiment of the present invention is W500mm × L250mm × T0.075mm, and when AC 220V, the rate of change is -3.45%, resistance before heat generation (Resistance before) 1449Ω of heating and 1399Ω of resistance after heating, which means that the smaller the resistance change rate of the heating element, the better the quality stability.

Next, the trip current relationship of the PTC constant temperature heating element (or the constant temperature heating element) according to the preferred embodiment of the present invention is shown in Table 13.

According to Table 13 and FIG. 4, the PTC constant temperature heating element (or the constant heating element) is constructed in an area where the PTC constant temperature heating element (or the constant temperature heating element) is constructed due to the limitation of the capacitance when the minimum trip current required to start the heating is too high. There is a limit.

Therefore, in the embodiment of the present invention when the heating area is 0.135M ² when AC 220V 0.12A, Heating Area 2.16M ² At 1.92A and heating area of 33M ² , the trip current of 29.33A was maintained so that the construction area of PTC constant temperature heating element was not limited.

In addition, the power consumption relationship of the PTC constant temperature heating element according to the preferred embodiment of the present invention is shown in Table 14.

According to Table 14 and Figure 5, the evaluation conditions and the results of the power consumption (Power Consumption) according to a preferred embodiment of the present invention, Heating Temp. 40 ℃, AC 220V, Active Area 0.125M ² , Ambient Temp. 17 ℃, Sample Size: W500mm * L250mm * T0.075mm The heating element surface temperature 40 ℃ at the same applied voltage, same area and same ambient temperature, the PTC constant temperature heating element of the applicant of the present invention (NDT) has the lowest as 22 (W) It shows power consumption.

In addition, the accelerated test and the Acceleration Test & Aging Test method of the PTC constant temperature heating element (or the constant temperature heating element) according to the preferred embodiment of the present invention, after installing the PTC constant temperature heating element in the oven at 80 ℃ PTC The constant temperature heating and abnormal overheat prevention characteristics were confirmed by applying power to the constant temperature heating element. At this time, the initial resistance is 1.364kΩ at 18 ℃, and the sample size of PTC constant temperature heating element (or constant temperature heating element) is W500mm × L250mm × T0.075mm. The relationship is shown in Table 15. and FIG.

According to Table 15 and Figure 6, how the temperature of the heating element is energized under the conditions of the ambient temperature of 80 ℃ for the PTC constant temperature heating element of the invention embodiment according to the applicant (NDT) and PTC constant temperature heating element or general heating element of other products It is showing if it is going up.

In the accelerated aging test of the PTC constant temperature heating element of the present invention (Korea NDT PTC) and PTC constant temperature heating element of Company A, it can be easily seen that the temperature rise due to the consumed power is hardly seen.

The reason is that as the temperature rises, the electrical resistance increases, the amount of current decreases and the amount of heat generated decreases. Due to the self-regulating (or constant temperature heating) characteristics of PTC, overheating and overcurrent can be prevented.

It was found that the general heating elements of other products could not obtain a proper PTC effect under such conditions and would eventually be destroyed by combustion.

The general criterion is that the PTC effect is tested by energizing the device (PTC constant temperature heating element or general heating element) at an ambient temperature of 20 ° C.

However, the test results of Table 15. and FIG. 6 above are accelerated time-varying tests to be conducted in a harsher environment than 20 ° C, and at the same time determine the suitability and effectiveness of PTC.

In addition, the resistance change test (RT Test) method according to the temperature of the PTC constant temperature heating element according to the preferred embodiment of the present invention, after installing the PTC constant temperature heating element in the oven, the oven temperature is increased by 10 ° C from 20 ° C to 150 ° C While measuring the resistance change of the PTC heating element. At this time, the initial resistance of the constant temperature heating element at room temperature 18 ℃ before installing the PTC constant temperature heating element in the oven is 1.283kΩ and the sample size of the PTC constant temperature heating element is W500mm × L250mm × T0.075mm. After the PTC heating element was installed in the oven, the resistance of the heating element was 1.3 kΩ at the oven temperature of 20 ° C, slightly higher than the initial resistance.The resistance of the heating element continuously increased as the oven temperature increased. PTC Intensity (R @ 150 ℃ / R @ 20 ℃) reached 2.5, and the resistance of the heating element returned to room temperature 18 hours after stopping the oven heating and leaving the heating element at room temperature. The temperature was 1.25 k 에서 and the change in resistance was 2.57%. The relationship is shown in Table 16. and FIG.

Hereinafter, the action of the thermothermal element using the polymeric PTC thermothermal ink according to a preferred embodiment of the present invention will be described in detail.

The present invention is a constant temperature heating element using a polymer PTC constant temperature heating ink which has a self temperature control characteristic in which a polymer PTC manufacturing technology and conductive particulate multi-walled carbon nanotubes (MWNT) are fused.

The constant temperature heating element is a pair of PET film (110a, 110b) having a thin surface and heat resistance and insulation and acts as an upper and lower cover of the constant temperature heating element, and a mat (Matt) and the edge of the lower PET film (110b) Any one of Ni, Ag, Sn, and Zn plated thin film is selected, and an adhesive 123 including a modified urethane adhesive 121 containing an ester compound and a TDI (Toluene Diisocianate) curing agent 122 is blended. A pair of metal electrodes 120a and 120b attached to each other and the front surface of the lower PET film 110b to prevent cracks occurring at the boundary between the lower PET film 110b and the metal electrodes 120a and 120b. Positive temperature coefficient to form a dry coating film between the ester nonwoven fabric 130 and the metal electrodes (120a, 120b) and the ester nonwoven fabric 130 that is seated on the substrate to enhance adhesion and have conductivity and magnetic temperature control characteristics. PTC device, a semiconductor material having characteristics (1 41) and a polymer PTC constant-temperature heating ink 140 in which a conductive polymer composition fused with MWNT or MWNT, Multi-walled Carbon Nanotube, 142, and a TDI-based curing agent 122 and a peroxide-based crosslinking agent were mixed. By including the self-temperature control characteristics of the polymer PTC constant temperature heating ink 140, it is possible to overcome the risk of damage to the heating element and fire caused by abnormal heating of the film-type constant temperature heating element for heating, and also multi-walled carbon nanotubes. Since the (MWNT) is fused, it has a unique characteristic to ensure the quality stability and reliability of the product by excellent return characteristics to the initial resistance after the heating of the constant temperature heating element.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

110a, 110b: PET (Polyethylene Terephthalate) Film
120a, 120b: metal electrode
121: modified urethane adhesive containing ester compound
122: Toluene Diisocianate (TDI) Curing Agent
123: Adhesive
130: ester nonwoven fabric
140: Positive Temperature Coefficient (PTC) Constant Temperature Heating Ink
141: PTC device
142: MWNT, MWNT, Multi-walled Carbon Nanotube

Claims (7)

In a constant temperature heating element using a polymer PTC constant temperature heating ink,
The constant temperature heating element has a thin surface, heat resistance and insulation, and is manufactured to a predetermined standard, but a pair of PET films (110a, 110b) serving as an upper and lower cover of the constant temperature heating element;
The modified urethane-based adhesive 121 and TDI containing an ester compound by selecting any one of Ni, Ag, Sn, and Zn having a matte treatment and a plated thin film on the edge of the lower PET film 110b. A pair of metal electrodes 120a and 120b attached by the adhesive 123 to which the (Toluene Diisocianate) -based curing agent 122 is combined;
It is seated on the front surface of the lower PET film (110b) to prevent cracks generated at the boundary between the lower PET film (110b) and the pair of metal electrodes (120a, 120b) and to prevent the flow of the pair of metal electrodes. Ester-based nonwoven fabric 130 and;
PTC device 141, which is a semiconductor material having a positive temperature coefficient characteristic so as to form a dry coating film between the metal electrodes (120a, 120b) and the ester-based nonwoven fabric 130 to enhance adhesion and have conductivity and magnetic temperature control characteristics ) Polymer PTC constant temperature heating ink in which conductive polymer composition fused with multi-walled carbon nanotube (MWCNT or MWNT, Multi-walled Carbon Nanotube, 142), TDI curing agent 122 and peroxide crosslinking agent 140) a constant temperature heating element using a polymer PTC constant temperature heating ink, characterized in that it is included.
The method according to claim 1,
The polymer PTC constant temperature heating ink is uniformly stirred with a dissolver after a bead mill dispersion process, and 100 g, 81.97 wt% of a Mill Base composition of the polymer PTC constant temperature heating ink is 10 g, 8.20 wt% of a TDI (Toluene Diisocianate) cross-linking agent for ester binders and 2 g, 1.64 wt% of DCP (Dicumyl Peroxide), a crosslinking agent for polyolefin binders, and 10 g, 8.20 wt% of xylene (Xylene) are introduced. Constant temperature heating element using a high-temperature PTC constant temperature heating ink.
The method according to claim 1,
The constant temperature heating element has a sample size of W500mm × L250mm × T0.075mm, AC 220V, initial resistance change rate (Rate of change) is -3.45%, resistance before heating is 1449Ω, resistance after heating (Resistance) after heating) is a constant temperature heating element using a polymer PTC constant temperature heating ink, characterized in that 1399Ω.
The method according to claim 1,
The trip current for the constant temperature heating element has a heating area of 0.135M ² when AC 220V is applied so that the construction area of the PTC constant temperature heating element is not limited. At 0.12A, 2.16M ² 1.92A, 33M ² Constant temperature heating element using a polymer PTC constant temperature heating ink, characterized in that the trip current (Trip Current) of 29.33A is maintained.
The method according to claim 1,
Power Consumption for the constant temperature heating element, the sample size of the constant temperature heating element W500mm * L250mm * T0.075mm, AC 220V, Active Area 0.125M ² , ambient temperature (Ambient Temp.) 17 ℃ And a heating element surface temperature (Heating Temp.) Of heating at 40 ° C., wherein the heating element is a constant temperature heating element using the polymeric PTC constant temperature heating ink.
The method according to claim 1,
Acceleration and change over time for the heating element, after installing the sample size W500mm × L250mm × T0.075mm of the heating element in the oven, by applying power to the PTC heating element at the oven temperature of 80 ℃ to prevent constant heating and abnormal overheating Initial resistance for the constant temperature heating element using a high temperature PTC constant temperature heating ink, characterized in that 18 ℃, 1.364kΩ.
The method according to claim 1,
The change rate of resistance to the constant temperature heating element is obtained by setting the sample size W500mm × L250mm × T0.075mm of the constant temperature heating element in the oven and then raising the oven temperature every 10 ° C from 20 ° C to 150 ° C. Initial resistance according to the resistance change is a constant temperature heating element using a high temperature PTC constant temperature heating ink, characterized in that 18 ℃, 1.283kΩ.

Images