JP5099025B2 - Planar heating element - Google Patents

Description

  The present invention relates to a sheet heating element used for, for example, an electric floor heating panel, an electric carpet and the like, and in particular, a pattern configuration of electrodes and resistors of a sheet heating element on which electrodes and resistors are printed on the same surface. It is about.

  Conventionally, as shown in FIG. 6, this type of planar heating element 21 includes a pair of conductive buses 23 a and 23 b obtained by printing a conductive silver polymer on an electrically insulating substrate 22 such as a polyester film and the like. Conductor passages 24a, 24b, 24c, and 24d that extend perpendicularly from the bus bars 23a and 23b and are printed parallel to each other to form a comb-shaped electrode are provided, and PTC conductive ink is provided on the conductor passages 24a to 24d. On the other hand, the resistor 26 is formed by printing in stripes perpendicularly and in parallel with each other. As a result, the heating regions 27a and 27b are formed between the conductor passages 24a to 24d.

  The PTC conductive ink for forming the heating regions 27a and 27b was obtained by adding carbon black to an ethylene vinyl acetate copolymer resin and mixing it with a solvent (see, for example, Patent Document 1).

  The PTC characteristic is a resistance temperature characteristic in which the resistance value increases as the temperature rises, and when the temperature reaches a certain temperature, the resistance value rapidly increases (takes the initial letter of English Positive Temperature Coefficient, which means that the resistance has a positive temperature coefficient) The heating region having the PTC characteristic can provide a planar heating element having a self-temperature adjusting function.

  In the planar heating element 21, as shown in FIG. 7, when the portion near the root extending from the conductive bus 23a in the conductor passage 24a is disconnected, that is, the conductor passage 24a is resistant to the conductor passage 24a like the disconnected portion C. When the portion where the body 26 overlaps is disconnected, if the disconnection interval is extremely small, corona discharge occurs, and heating that is electrically connected from the disconnected portion C to the tip of the conductor passage 24a as shown in FIG. If the electric power corresponding to the combined resistance of the region, that is, the region (c), that is, the force for applying electricity to the disconnected portion C is more than necessary to generate the spark, then the dielectric breakdown occurs and the spark is generated. However, since the heat generated by the spark is dissipated to the resistor 26 and the periphery thereof overlapping the disconnected portion C, the disconnected portion C of the conductor passage 24a does not evaporate, and the disconnection interval is extremely small. Spark is continued while maintaining a.

  Furthermore, due to the heat generated by the spark, the resistor 26 overlying the broken portion C of the conductor passage 24a gradually changes in quality, a carbon-connected bypass path is formed, current flows, and the resistance value of the bypass path is reduced. When it is a certain moderate value, the phenomenon of causing abnormal heating in the bypass path occurs.

In order to solve this abnormal heating phenomenon, as shown in FIG. 8, a pair of main electrodes 3a and 3b are printed on a substrate 2 such as a polyester film, and are alternately extended from the main electrodes 3a and 3b. The branch electrodes 4a and 4b are printed in such a manner that the connection electrodes 5a are divided into a plurality of branches from the branch electrodes 4a and 4b, and are independently branched in parallel with the branch electrodes 4a and 4b. A sheet heating element 1 having a configuration in which a non-printing portion 7 is provided between the branch electrodes 4a and 4b and a resistor 6 is printed between the connection electrodes 5 of different polarities is devised. Yes.
Japanese Patent Laid-Open No. 3-129893

  In the sheet heating element 1, as shown in FIG. 9, the resistor 6 is formed by printing, and the printed pattern 8 of the resistor 6 may exceed the connection electrode 5 due to variations in the printing position.

  The printing method usually employs screen printing in order to cope with various printing shapes. In screen printing, pressure is applied so that the ink placed on the screen plate is pushed into the screen plate by means of a rubber plate called a squeegee, and the print object is passed through the micro holes forming the printing pattern provided on the screen plate. It is a printing method to adhere. Therefore, if there is a gap between the printing object and the screen plate, the ink spreads on the back side of the printing plate toward the printing end side of the printing pattern and adheres to the printing object. This is generally called blurring.

  As shown in FIG. 10, when the printed pattern 8 of the resistor 6 exceeds the connection electrode 5, the screen plate 9 comes into contact with the connection electrode 5 and does not lower any more. Therefore, between the screen plate 9 and the substrate 2. The gap 11 is generated by the thickness of the connection electrode 5, and the blur 10 is generated as shown in FIG. If the blur 10 is severe, the resistor 6 adheres to the branch electrodes 4a and 4b, so that the resistor 6 is electrically connected to the branch electrodes 4a and 4b. Therefore, the abnormal heating phenomenon cannot be fundamentally solved.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a planar heating element that does not cause an abnormal heating phenomenon depending on the result of actual processing including printing variations.

  In order to solve the above-described problems, an electrically insulating substrate, at least a pair of main electrodes printed on the substrate, a branch electrode printed so as to alternately extend from the main electrode, and a branch electrode The connection electrode is divided into a plurality of parts and is independently branched substantially parallel to the branch electrode and printed in pairs at opposite positions. The connection electrode is electrically connected to the connection electrode and is opposed to the connection electrodes of different polarities. A resistor which is printed between the positions and has a non-printing portion provided between the branch electrodes, and the distance between the connection electrode on the printing start side printed in a pair and the branch electrode at the branch source Also, a large distance is provided between the connection electrode on the printing end side and the branch electrode at the branch source.

  According to this configuration, the distance between the connection electrode on the printing end side and the branch electrode at the branch end is larger than the distance between the connection electrode on the print start side and the branch source branch electrode printed in pairs. Since the resistor print pattern exceeds the connection electrode and bleeding occurs, the blurred resistor does not adhere to the branch electrode, so the blurred resistor is electrically connected to the branch electrode. The abnormal heating phenomenon can be suppressed by the actual processing result including the printing variation and the like without being connected to the printer.

  According to the planar heating element of the present invention, the connection electrode on the printing end side and the branch electrode on the branch end side are closer than the distance between the connection electrode on the printing start side printed in pairs and the branch source branch electrode. Therefore, even if the printed pattern of the resistor exceeds the connection electrode and bleeding occurs, the blurred resistor does not adhere to the branch electrode. It is not electrically connected to the branch electrode, and the occurrence of the abnormal heating phenomenon can be suppressed by the actual processing result including the printing variation.

The present invention comprises an electrically insulating substrate, at least a pair of main electrodes printed on the substrate, a branch electrode printed so as to alternately extend from the main electrode, and a plurality of branches from the branch electrode. The connection electrodes that are independently branched in parallel with the branch electrodes and printed in pairs at opposite positions, and are electrically connected to the connection electrodes and printed between the opposite positions of the connection electrodes of different polarities. And a resistor having a non-printing portion provided between the branch electrodes and the printing end side rather than the distance between the connecting electrode on the printing start side and the branching source branch electrode printed in a pair. The distance between the connection electrode and the branch electrode at the branch source is large.

  Accordingly, the distance between the connection electrode on the printing end side and the branch electrode at the branch end is set larger than the distance between the connection electrode on the printing start side printed in a pair and the branch electrode at the branch source. Therefore, even if the printed pattern of the resistor exceeds the connection electrode and blurring occurs, the blurred resistor does not adhere to the branch electrode, so the blurred resistor is electrically connected to the branch electrode. The abnormal heating phenomenon can be suppressed by the actual processing result including the printing variation.

  In particular, a printing pattern is provided so that the resistor is printed in a range not exceeding the connection electrode printed in a pair at the opposite position.

  Thereby, the printing end side of the printing pattern is on the connection electrode, and since there is no gap between the screen plate and the connection electrode, bleeding does not occur and abnormal heating phenomenon does not occur.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a plan view of a planar heating element according to the first embodiment of the present invention.

  In FIG. 1, a sheet heating element 1a is formed by printing and drying a silver paste on an electrically insulating substrate 2 such as a polyester film to form main electrodes 3a and 3b, and alternately extending from the main electrodes 3a and 3b. Thus, the branch electrodes 4a and 4b are formed. Further, the connection electrodes 5a and 5b are branched from the branch electrodes 4a and 4b in a key shape, and the connection electrodes 5a and 5b are arranged at positions facing each other. In the embodiment of the present invention, the branch electrodes 4a and 4b have a width of 2 mm, and the connection electrodes 5a and 5b have a width of 1.4 mm.

  Between the connection electrodes 5a and 5b, polymer resistor ink is printed and dried to form the resistor 6a, and the resistor 6a is printed and dried between the resistor 6a and the branch electrodes 4a and 4b. There are no non-printing parts 7a, 7b. In the embodiment of the present invention, the distance between the connection electrode 5b of the non-printing portion 7b and the branch electrode 4b is 2.5 to 3 mm, and the distance between the connection electrode 5a of the non-printing portion 7a and the branch electrode 4a is 1.5. It is set to ~ 2 mm.

  As the polymer resistor ink, a polymer resistor in which carbon is kneaded into a resin is dissolved in a solvent, or in particular, a polymer resistor in which carbon is kneaded into a crystalline resin is dissolved in a solvent. .

  Next, the operation and action will be described.

In FIG. 2, by design, the printed pattern 8a of the resistor 6a starts printing from a position where it enters the 0.5 mm connection electrode 5a out of the 1.5 mm width of the connection electrode 5a, and the 1.5 mm of the connection electrode 5b. Since it is considered that printing ends at a position within 0.5 mm of the width on the connection electrode 5b, originally there is no gap 11 between the connection electrodes 5a and 5b and the screen plate 9 as shown in FIG. Therefore, the polymer resistor ink does not spread from the printing end side of the printing pattern 8a to the back surface of the screen plate 9, and the blur 10 does not occur.

  However, in actuality, printing variations, that is, misalignment (± 0.5 mm) of the printing pattern 8a of the resistor 6a during printing, and printing and drying of the main electrodes 3a and 3b, the branch electrodes 4a and 4b, and the connection electrodes 5a and 5b are performed. Due to the contraction of the distance between the connection electrodes 5a and 5b (0.1 mm) due to the contraction of the electrically insulating substrate 2, the connection is made on the printing start side or the printing end side of the printing pattern 8a of the resistor 6a as shown in FIG. There is a possibility that the printed pattern 8a of the resistor 6a enters the non-printing part 7a or 7b beyond the electrode 5a or 5b by a maximum of 0.1 mm.

  In this case, as shown in FIG. 5, since the screen plate 9 is in contact with the connection electrodes 5a and 5b and a gap 11 corresponding to the thickness of the connection electrodes 5a and 5b is formed between the screen plate 9 and the electrically insulating substrate 2, When the print pattern 8a passes from the connection electrode 5b on the printing end side, the polymer resistor ink spreads on the back surface of the screen plate 9, and a blur 10 is generated. Usually, this blur is about 2 mm at the maximum.

  However, as shown in FIG. 4, since the distance between the connection electrode 5b and the branch electrode 4b of the non-printing portion 7b on the printing end side of the printing pattern 8a of the resistor 6a is 2.5 to 3 mm, the blur 10 is not applied. Even if it adheres to the printing part 7b, the blur 10 does not adhere to the branch electrode 4b, and the resistor 6a and the branch electrode 4b are not electrically connected, so that an abnormal heating phenomenon does not occur.

  Also, by design, printing of the printed pattern 8a of the resistor 6a is started from a position where the printed electrode 8a enters the 0.75mm connecting electrode 5a out of the 1.5mm width of the connecting electrode 5a, and the connecting electrode 5b has a width of 1.5mm. Of these, if printing is considered to end at a position on the 0.75 mm connection electrode 5b, printing variations, that is, a positional deviation (± 0.5 mm) of the printing pattern of the resistor 6a during printing, and the main electrodes 3a and 3b will occur. Even when the distance between the connection electrodes 5a and 5b is contracted (0.1 mm) due to the contraction of the electrically insulating substrate 2 when the branch electrodes 4a and 4b and the connection electrodes 5a and 5b are printed and dried, the resistor 6a Since the printing pattern 8a of the resistor 6a enters a position within 0.15 mm of the width of the connection electrode 5a or 5b on the printing start side or printing end side of the printing pattern, the screen plate 9 and the connection power are connected. 5a or 5b is in contact, never bleeding 10 occurs. Therefore, since the resistor 6a and the branch electrode 4b are not electrically connected, the abnormal heating phenomenon does not occur.

  As described above, the planar heating element according to the present invention includes the connection electrode on the printing end side and the branching source with respect to the distance between the connection electrode on the printing start side and the branching source electrode printed in pairs. Since the printed pattern of the resistor exceeds the connection electrode and bleeding occurs, the blotted resistor does not adhere to the branch electrode. The resistor is not electrically connected to the branch electrode, and the occurrence of abnormal heating phenomenon can be suppressed by the actual processing results including printing variations, etc., so heating of floor heating panels, electric carpets, etc. The present invention is not limited to products, and can be applied to all heating elements in which a resistor is formed in a plane and a power supply electrode is arranged.

The top view which shows the structure of the planar heating element in Embodiment 1 of this invention The partial expanded plan view which shows the structure of the planar heating element in Embodiment 1 of this invention AA sectional view of a sheet heating element in Embodiment 1 of the present invention. The partial expanded plan view which shows the implementation state of the planar heating element in Embodiment 1 of this invention BB sectional drawing of the planar heating element in Embodiment 1 of this invention Plan view of a conventional planar heating element The top view which shows the state of the disconnection part C part of the conventional planar heating element Plan view of another conventional sheet heating element Partially enlarged plan view showing the configuration of another conventional sheet heating element CC sectional view of another conventional sheet heating element

1, 1a, 21 Planar heating element 2, 22 Substrate 3a, 3b Main electrode 4a, 4b Branch electrode 5, 5a, 5b Connection electrode 6, 6a Resistor 7, 7a, 7b Non-printing part 8, 8a Print pattern 9 Screen Plate 10 Smudge 11 Crevice 23a, 23b Busbar 24a, 24b, 24c, 24d Conductor path 26 Resistor 27a, 27b Heating area

Claims (2)

An electrically insulating substrate, at least a pair of main electrodes printed opposite to each other on the substrate, branch electrodes printed so as to alternately extend from the main electrodes, and divided into a plurality from the branch electrodes A connection electrode that is independently branched substantially parallel to the branch electrode and is printed in pairs at opposite positions, and electrically connected to the connection electrode, and between the opposite positions of the connection electrodes of different polarities. A resistor that is printed and has a non-printing portion provided between the branch electrodes, and prints more than the distance between the connection electrode on the printing start side printed in a pair and the branch electrode at the branch source. A planar heating element having a large distance between the connection electrode on the end side and the branch electrode at the branch source. The planar heating element according to claim 1, wherein the resistor is provided with a printing pattern so as to print within a range not exceeding a connection electrode printed in a pair at an opposing position.