JP2011034905A - Planar heating element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a uniform heat generating state by suppressing crack formation of a polymer resistor. <P>SOLUTION: A planar heating element includes: an electrical insulating substrate 1; an electrode 4 which includes a pair of the main electrodes 2a, 2b arranged to be mutually opposed and connecting electrodes 3a, 3b branched respectively from the main electrodes in a comb-shape state, and is formed on the electrical insulating substrate by printing; and the polymer resistor 5 printing-formed on the electrical insulating substrate to be superimposed on the connecting electrodes. Side parts of the connecting electrodes 3a, 3b are stepwisely constituted. Accordingly, when ink of the polymer resistor is printed so as to cover the edge part of the connecting electrodes, since the edge part is stepwise, formation of a slit crack can be suppressed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a planar heating element used for a heating device such as an electric floor heating panel and an electric carpet.

  Conventionally, as shown in FIG. 4, this type of planar heating element includes a pair of main electrodes arranged so as to face each other, and connection electrodes 101 and 102 branched from the main electrodes in a comb-tooth shape, respectively. In addition, the polymer resistor 104 made of PTC conductive ink was printed so as to cover the connection electrodes 101 and 102 and dried.

  The PTC conductive ink is made 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 means a resistance temperature characteristic (Positive Temperature Coefficient) in which the resistance value increases as the temperature rises, and when the temperature reaches a certain temperature, the resistance value rapidly increases. A planar heating element having a temperature adjusting function can be provided.

Japanese Patent Laid-Open No. 3-129893

  In the conventional sheet heating element, a step 105 is formed at the boundary between the connection electrodes 101 and 102 and the electrically insulating substrate 103. Normally, a polymer resistor is formed so as to cover the connection electrodes 101 and 102. When 104 is printed, the polymer resistor 104 also forms a film at the edge portion 106 of the step 105.

  The polymer resistor 104 connection electrodes 101 and 102 are physically and electrically connected by entering the step 104 by its own weight and being dried.

  However, depending on variations in physical properties due to the manufacturing process of the polymer resistor 104 and variations in printing conditions in the printing process, the film of the polymer resistor 104 is floated in the air by the step 105, and its own weight causes electrical insulation. When displacing in the direction of the substrate 103, the edge portion 106 may act as a cutter, and a slit-shaped tear 107 may occur.

  When dried in that state, the polymer resistor 104 and the connection electrodes 101 and 102 are not physically and electrically connected.

  Therefore, the polymer resistor 104 in the portion where the tear 107 is generated does not generate heat, and if the tear 107 is large and the connection portion with the connection electrodes 101 and 102 is small, current concentration occurs and abnormal heat generation occurs. There was a problem.

In order to solve this problem, it is possible to reduce the printed film thickness of the connection electrodes 101 and 102 to reduce the step difference between the electrical insulating substrate 103 and the connection electrodes 101 and 102. Then, since the resistance value at that portion increases, there is a problem that a predetermined current does not flow and sufficient heat generation cannot be obtained.

  The present invention solves the above-described conventional problems, and provides a planar heating element that exhibits uniform heat generation characteristics even when there are variations in physical properties and printing conditions due to the manufacturing process of the polymer resistor. For the purpose.

  In order to solve the above-described conventional problems, the present invention includes an electrically insulating substrate, a pair of main electrodes disposed so as to face each other, and a connection electrode branched from each of the main electrodes in a comb shape. And an electrode formed by printing on the electrically insulating substrate, and a polymer resistor printed on the electrically insulating substrate so as to overlap the connecting electrode, and the side portion of the connecting electrode is It is structured in stages.

  Therefore, when the ink of the polymer resistor is printed so as to cover the edge portion of the connection electrode, the edge portion is stepped, so that it is possible to suppress the occurrence of slit-like tears.

  According to the planar heating element of the present invention, no slit-like rift occurs in the film of the polymer resistor, and therefore the polymer resistor can be heated uniformly.

The top view which shows the structure of the planar heating element in Embodiment 1 of this invention Enlarged sectional view of the main part The principal part expanded sectional view of the planar heating element in Embodiment 2 of this invention Main section enlarged sectional view of a conventional sheet heating element

  The present invention comprises an electrically insulating substrate, a pair of main electrodes arranged so as to face each other, and a connection electrode branched from each of the main electrodes in a comb-tooth shape, and printed on the electrically insulating substrate And a polymer resistor printed on the electrically insulating substrate so as to overlap the connection electrode, and the side portion of the connection electrode is formed in a stepped manner.

  As a result, when the polymer resistor ink is printed so as to cover the side portions of the connection electrodes, the ink film is deposited on the electrically insulating substrate before the slit-shaped tear is generated.

  Therefore, the electrical connection between the connection electrode and the polymer resistor is ensured, and a uniform heat generation state is obtained.

  The step shape of the side portion of the connection electrode is formed by, for example, positioning the second connection electrode having a narrow width on the first connection electrode having a wide width or the second connection so as to cover the first connection electrode. This can be realized by printing the electrodes to form connection electrodes.

  And if these planar heating elements are mounted on a warming tool as a heating source, they can be used for efficient heating.

  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)
1 and 2, a pair of main electrodes 2a and 2b arranged so as to face each other on an electrically insulating substrate 1 such as a polyester film, and the main electrodes 2a and 2b branch into comb teeth. An electrode 4 composed of the connected electrodes 3a and 3b is formed.

  The electrode 4 comprising the main electrodes 2a and 2b and the connection electrodes 3a and 3b is obtained by printing and drying a silver paste.

  The connection electrodes 3a, 3b are first printed with a wide first connection electrode 3c, 3d on the electrically insulating substrate 1, dried, and then a narrow second connection electrode 3e, 3f is formed by printing and drying, and as a result, the side portions of the connection electrodes 3a and 3b are set stepwise.

  The main electrodes 2a and 2b are formed by printing and drying the connection electrodes 3a and 3b after printing and drying.

  The polymer resistor 5 is formed by printing ink of a polymer resistor so as to cover the connection electrodes 3a and 3b, and then drying.

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

  In the above configuration, when the ink of the polymer resistor 5 is printed so as to cover the connection electrodes 3a and 3b, the film falls by its own weight, and the first connection electrodes 3c and 3d and the second connection electrodes 3e and 3f The steps 3g and 3h between the first connection electrodes 3c and 3d and the steps 3i and 3j between the electrically insulating substrate 1 are moved and sequentially landed.

  Assuming that the steps 3g and 3h and the steps 3i and 3j have the same height, it becomes half of the conventional steps, so that no slit-like rift occurs in the ink film.

  Therefore, there is no problem that the polymer resistor 5 does not generate heat or abnormal heat is partially generated, and heat can be generated uniformly.

  The step is not specified as two steps, and may be three or more steps.

(Embodiment 2)
FIG. 3 shows the second embodiment. The difference from the first embodiment is that the second connection electrodes 3e and 3f are printed and dried so as to cover the first connection electrodes 3c and 3d. 3g, 3h and steps 3i, 3j are formed.

  Note that parts having the same action as in FIG. 2 are denoted by the same reference numerals, and those of the first embodiment are used for specific description.

  In the above configuration, the operation and effect are basically the same as those in the first embodiment. However, in this embodiment, the corners of the steps 3g and 3h and the steps 3i and 3j are rounded, and the cutter Therefore, the possibility of the formation of slit-like rifts is further reduced.

  As described above, the planar heating element according to the present invention includes an electrically insulating substrate, a pair of main electrodes disposed so as to face each other, and a connection electrode branched from each of the main electrodes in a comb shape. An electrode formed by printing on the electrically insulating substrate, and a polymer resistor printed on the electrically insulating substrate so as to overlap the connecting electrode, and a side portion of the connecting electrode Since it is structured in stages, there is no tearing during polymer resistor formation, and a uniform heat generation state can be obtained. For example, if it is used for heating equipment such as electric floor heating panels and electric carpets, reliable heating An effect is obtained.

DESCRIPTION OF SYMBOLS 1 Electrically insulating board | substrate 2a, 2b Main electrode 3a, 3b Connection electrode 3c, 3d 1st connection electrode 3e, 3f 2nd connection electrode 3g, 3h, 3i, 3j Level | step difference 4 Electrode 5 Polymer resistor

Claims (4)

An electrically insulating substrate, a pair of main electrodes arranged so as to face each other, and a connection electrode branched from each of the main electrodes in a comb shape, and formed on the electrically insulating substrate by printing A planar heating element comprising an electrode and a polymer resistor printed on the electrically insulating substrate so as to overlap the connection electrode, wherein the side portion of the connection electrode is formed in a stepped manner. The planar heating element according to claim 1, wherein the second connection electrode having a narrow width is positioned on the first connection electrode having a wide width to form a connection electrode. The planar heating element according to claim 1, wherein the connection electrode is formed by printing the second connection electrode so as to cover the first connection electrode. The heating tool which mounted the planar heating element of any one of Claims 1-3 as a heating source.