JPS6215707A - Flexible heat sensitive wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a flexible thermosensitive electric wire used in cloth electric heating devices such as electric blankets and electric bed blankets.

Conventional technology Conventionally, electric heating devices made of cloth such as electric blankets and electric bed blankets were
There was a strong demand for washing as it comes into direct contact with the grooves. In order to solve this problem, it is possible to prevent corrosion of the connection bins of electrical components inside the blanket and tracking between terminals, or to use flexible thermosensitive wires made of polyamide copolymers or polyamide compositions as polymer thermosensors. Electric blankets and electric blankets that can be washed with water have been developed. - Problems to be Solved by the Invention Blankets are generally washed by dry cleaning companies unless otherwise specified. However, with conventional electric blankets, etc., when dry-cleaned, the properties of the flexible heat-sensitive wires placed inside the blanket are significantly affected by its solvents such as parklene (tetrachloroethylene) and petroleum-based solvents. There was a problem with it changing. Specifically, it is as follows.

(1) A polymer thermosensitive body such as a polyamide copolymer or a polyamide composition to which a plasticizer for improving properties is added is used in the temperature sensitive bath. These polymer thermosensitive materials have extremely low crystallinity compared to polyamides such as nylon 11 and nylon 12. Therefore, the dry cleaning solvent that has passed through the outer coating layer easily diffuses and contains the solvent.
The electrical characteristics will change significantly.

(2) The plasticizer of the polyvinyl chloride used as the insulating jacket is eluted by the dry cleaning solvent, causing it to lose its flexibility and greatly reduce its thickness.

On the other hand, in a flexible heat-sensitive wire, if the temperature-sensitive layer is thin, the impedance is low and the breakdown temperature due to self-heating is lowered.

Moreover, if it is thick, polyamide is used as the base material, so the melt viscosity is low and eccentricity occurs during molding, so it is used at a thickness of about 0.3 mm. Therefore, the impedance of the flexible thermosensitive wire is determined by the polymer thermosensitive material, and there is a problem in that it is difficult to adjust the impedance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a flexible thermosensitive electric wire that can be used in cloth electric heating devices such as electric blankets and electric bed blankets, allows dry cleaning, and allows easy adjustment of impedance.

Means for Solving the Problem A flexible thermosensitive layer consisting of a thermosensitive layer made of a polymeric thermosensitive material and an electrode provided through the layer are arranged concentrically, and an insulating jacket is provided over the thermosensitive layer. In the thermosensitive electric wire, a barrier layer made of a thermoplastic resin against a dry cleaning solvent is provided between the temperature sensitive layer and an electrode provided on the outside thereof, and the insulating jacket is made of a non-leaching material.

Highly crystalline and flexible resins such as resins with functional hydrogen bonds and fluorine-containing resins have dense structures and have low affinity for solubility parameters, which are different from the values of dry cleaning solvents (approximately 7.8 to 9.3). , the solvent permeability is extremely low, and the solvent content during solvent immersion is extremely low. Therefore, by providing these thermoplastic resins as a barrier layer between the temperature-sensitive layer of a flexible thermosensitive wire and the electrode provided on the outside thereof, it is possible to prevent solvents from reaching and diffusing into the temperature-sensitive layer during dry cleaning. This makes it possible to dry clean cloth electric heating devices such as electric blankets and electric bed blankets.

Further, the impedance of the flexible thermosensitive wire is a composite impedance of the impedance of the thermosensitive layer and the impedance of the barrier layer connected in series therewith. Therefore, the impedance of the flexible thermosensitive wire can be easily adjusted by changing the type and thickness of the thermoplastic resin used in the barrier layer. In addition, since the solvent content of these thermoplastic resins when immersed in a solvent is extremely small, the change in impedance is very small, and since it becomes a composite impedance with the impedance of the temperature-sensitive layer, the change is further reduced, which poses a practical problem. Not.

The polymer thermosensitive body used in the flexible thermosensitive electric wire of the present invention is
Resistance, capacitance, or impedance decreases with increasing temperature, and this is the case for polyamide copolymers and polyamide compositions.

On the other hand, dry cleaning generally requires about 30 degrees of processing time per process, and uses perchloren or petroleum-based solvents as the solvent. Therefore, as a flexible thermosensitive wire, it is necessary that the change in characteristics is small during at least this period of time, and that the flexibility of the outer sheath is not lost by repeating this process.

Example Hereinafter, the present invention will be explained in detail using examples.

Example 1 FIG. 1 is a partially cutaway side view of a flexible thermosensitive electric wire of the present invention.

In FIG. 1, 1 is a polyester core thread, 2 and 6 are ribbon-shaped electrodes made of a spirally wound copper alloy, and 3 is a ribbon-shaped electrode 25 provided on the electrode 2 with a thickness of about 0.3ffll+. %
a temperature-sensitive layer made of N-substituted nylon; 4 is a barrier layer made of ethylene-vinyl alcohol copolymer provided with a thickness of about 0.12 mm between the temperature-sensitive layer 3 and the outer electrode 6;
Reference numeral 6 denotes an insulating jacket made of vinyl chloride-urethane copolymer provided on the outside of these. Using this flexible thermosensitive wire, an immersion test (30 minutes immersion-6
Q″C was left standing for 30 minutes (repeated 10 times), and the impedance-temperature characteristics before and after the test were measured.

Figure 2 shows the characteristics of a length of 177L. 7' and 8 in the figure represent the characteristics of this example before and after the test, respectively.

In addition, 9.10 in the figure indicates that the barrier layer 4 in FIG.
These are the characteristics before and after the test of a conventional example in which the insulating jacket 6 was made of plasticized polyvinyl chloride.

Example 2 Using a flexible thermosensitive wire with a barrier layer 4 made of ethylene-vinyl alcohol copolymer of about 0.2 mm in thickness as shown in Fig. An immersion test (conditions were the same as in Example 1) was conducted. Figure 3 shows the impedance-temperature characteristics for a 1 m length. 11 in the diagram.
12 shows the characteristics of this example before and after the test, respectively. Further, 13 and 14 in the figure are the characteristics before and after the test of the conventional example used in Example 1.

Example 3 As the barrier layer 4 in FIG.
An immersion test in percrene (the conditions are the same as in Example 1) was conducted using a flexible thermosensitive electric wire with a temperature of 15 fflff and an insulating jacket 6 made of a mixture of polyvinyl chloride and polyurethane. Figure 4 shows the impedance-temperature characteristics for a 1 m length. 15.18 in the figure are the characteristics of this example before and after the test, respectively. Also, 17.18 in the figure is
These are the characteristics before and after the test of the conventional example used in Example 1.

In this way, compared to the conventional example, the flexible thermosensitive wire of this example shows extremely little change in characteristics before and after the immersion test, and the impedance can be easily adjusted by adjusting the type and thickness of the material used as the barrier layer. can do. In addition, in the conventional example, the plasticizer in the insulating jacket was eluted during the immersion test, causing its thickness to become thin and losing flexibility, whereas in this example, there was no change before and after the immersion test. I couldn't see it.

As the barrier layer of the flexible thermosensitive electric wire of the present invention, a highly crystalline thermoplastic resin such as a resin having hydrogen bonds or a fluororesin is used. Specifically, polyamide, ethylene-
Vinyl alcohol copolymer.

Examples include polyvinylidene fluoride, polychlorotrifluoroethylene, polyvinylidene chloride, and polyethylene terephthalate, and mixtures containing these may also be used. This type of flexible heat-sensitive wire is normally used as a temperature sensor or heat-sensitive heater at temperatures below about 6Q''C.It also detects the temperature in abnormal situations such as local heating and suppresses the temperature rise. In order to have these functions at the same time, it is necessary that the impedance decreases as the temperature rises even in high-temperature areas. Suitable barrier layer materials for this purpose include polyamide, ethylene-vinyl alcohol copolymer, and polyvinylidene fluoride. Or a mixture containing these.

Since the flexible thermosensitive wire is used in a warming device made of cloth, it is desirable that the insulating jacket covering the conductive part is flame retardant. Polyvinyl chloride is flame retardant, and using this copolymer or a mixture containing these as an insulating jacket increases safety in the event of abnormal heating, and since it is non-leaching, it does not lose flexibility when immersed in a solvent. .

Effects of the Invention According to the present invention, it is possible to provide a flexible thermosensitive electric wire that can be used in cloth heating devices such as electric blankets and electric bed blankets, can be dry-cleaned, and whose impedance can be easily adjusted.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of the flexible thermosensitive electric wire of the present invention, and FIGS. 2, 3, and 4 are the impedance-temperature characteristics of Examples 1 to 3 and the conventional example before and after immersion in solvent. . 1... Core thread, 2, 5... Electrode, 3...
...Temperature-sensitive layer, 4...Barrier layer, 6...
...Insulating jacket. Name of agent: Patent attorney Toshio Nakao and one other person I.
・Charge/Thread 25 Electric Figure 1 3 Temperature-sensitive layer 6 ・Cut Figure 2 Figure 3 Temperature ('C) Figure 4

Claims (4)

[Claims] (1) A flexible structure consisting of a temperature-sensitive layer made of a polymer thermosensitive material and a pair of electrodes provided through the temperature-sensitive layer in a concentric configuration, and an insulating jacket provided over these layers. A thermoelectric wire, between a temperature-sensitive layer and an electrode provided on the outside thereof,
A flexible thermosensitive electric wire characterized by having a barrier layer made of a thermoplastic resin against dry cleaning solvents and having an insulating jacket made of a non-eluting resin. (2) The flexible thermosensitive electric wire according to claim 1, wherein the barrier layer is made of a highly crystalline resin. (3) The flexible thermosensitive electric wire according to claim 2, wherein the highly crystalline resin is polyamide, ethylene-vinyl alcohol copolymer, polyvinylidene fluoride, or a mixture containing these. (4) The flexible thermosensitive electric wire according to claim 1, wherein the insulating jacket is made of a vinyl chloride copolymer or a thermoplastic resin whose main material is polyvinyl chloride.