JPS6298504A - 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] This invention relates to flexible heat-sensitive electric wires.

Conventional Technology In the past, electric blankets and the like came into direct contact with the skin, so there was a strong demand for cleansing. On the other hand, electric blankets that can be washed with water have been developed by using flexible heat-sensitive electric wires using polymer heat-sensitive materials made of boramid compositions with low hygroscopicity.

On the other hand, in order to make electric blankets dry-cleanable, in order to impart solvent resistance to flexible thermosensitive electric wires, we developed a highly solvent-barrier material made of ethylene-vinyl alcohol copolymer or highly crystalline polyolefin. A flexible thermosensitive electric wire in which a non-leaching polymeric material such as a molecular material, an ethylene-vinyl chloride copolymer, or a polymer alloy of this and polyvinyl chloride is provided on a polymeric thermosensitive layer was disclosed in Japanese Patent Application Laid-Open No. 1986-60. It is disclosed in Japanese Patent No. 89901.

Problems to be Solved by the Invention Even if a low-hygroscopic polymer heat-sensitive material is used in a flexible heat-sensitive wire, a layer of polymeric material such as a barrier polymeric material or a non-eluting polymeric material may be added on top of it. If provided, this prevents the release of moisture from the polymer heat susceptor or the material inside it, resulting in very slow recovery of its heat-sensitive properties and the blanket temperature changing over a long period of time when actually used as an electric blanket. There was a problem.

The present invention relates to flexible thermosensitive wires used in electric heating devices such as electric blankets, and which fully brings out the characteristics of polymer thermosensitive materials and enables dry cleaning of electric blankets and the like. The purpose is to provide.

Means for Solving the Problems The flexible thermosensitive wire of the present invention has a polymer thermosensitive layer between a pair of electric wires, and the outer periphery of the wire contains a hydrophilic group having a barrier property against dry cleaning solvents. A polymeric material layer and a moisture permeable outer covering layer are sequentially provided.

Action Polymer materials with barrier properties against dry cleaning solvents include ethylene-vinyl alcohol copolymers, highly crystalline polyolefins, polyvinylidene halides, fluorine-containing polymers, polyamides, metal chelate-containing polymers, acrylonitrile copolymers, etc. There is. These materials exhibit excellent barrier properties due to their high crystallinity, but their bending modulus is higher than that of soft polymer materials commonly used as outer sheaths, so they are used as the outermost layer (on the sheath) of flexible thermosensitive wires. If it is provided as a barrier polymer material layer, its flexibility will be reduced, making it difficult to use. Therefore 1. It is desirable that the flexible heat-sensitive wire is provided on the polymer heat-sensitive layer, a barrier polymer material layer, and an outer covering layer in this order. Furthermore, among these barrier polymer materials, those with hydrophilic groups such as hydroxyl groups and amide groups have good affinity with water molecules and have very good moisture permeability. Exhibits excellent barrier properties against dry cleaning solvents and high moisture permeability. On the other hand, for the outer covering layer, a soft polymeric material that exhibits moisture permeability equal to or higher than the above-mentioned barrier-property hydrophilic group-containing polymeric material and has excellent solvent resistance is suitable.

Therefore, by combining the above-mentioned barrier hydrophilic group-containing polymer material and a moisture-permeable jacket on the polymer heat-sensitive layer of a flexible thermo-sensitive wire, and sequentially providing these, an excellent flexible thermo-sensitive wire can be obtained. Achievable Example Barrier polymer material refers to a polymer material that has low permeability to dry cleaning solvents and a high barrier level.

The barrier hydrophilic group-containing polymeric material in the present invention is a polymeric material having a hydroxyl group, an amide group, or a carboxyl group, and specifically includes ethylene-vinyl alcohol copolymer and polyamide. Random or alternating copolymers are suitable for the ethylene-vinyl alcohol copolymer from the viewpoint of moisture permeability. Polyamides include nylon 6 and nylon 11.
, nylon homopolymers such as nylon 12, and polyamide copolymers such as boetheramide, polyesteramide, and N-substituted polyamide. Among these, nylon homopolymers exhibit excellent barrier properties due to their high crystallinity. Furthermore, when a nylon homopolymer has a high concentration of amide groups, such as nylon 6, the bending elastic modulus increases and the flexibility of the wire as a flexible thermosensitive wire decreases. From the above, the barrier hydrophilic group-containing polymer material in the present invention is nylon 11 or nylon 12.
is most suitable.

As the moisture-permeable outer covering, a soft polymeric material that exhibits moisture permeability equal to or higher than the above-mentioned barrier hydrophilic group-containing polymeric material and has excellent solvent resistance is suitable. There are various soft polymer materials, but polyvinyl chloride compositions contain vinyl chloride units, so it is easy to impart flame retardancy, and general-purpose flame retardants such as antimony oxide can be used. By blending, high flame retardancy with a limiting oxygen index of 25 or more can be imparted. Therefore, it is suitable as a material 7 for the jacket of this type of flexible thermosensitive electric wire.

Polyvinyl chloride is easily softened by blending with other polymers or by using plasticizers. Blend polymers with high moisture permeability are those with urethane groups or ester groups that have a relatively good affinity with water molecules, such as polyurethane, vinyl chloride-urethane copolymers, vinyl chloride-acrylic copolymers, chloride Vinyl chloride copolymers such as vinyl-vinyl acetate copolymers. Among these, polyurethane or vinyl chloride-urethane copolymer is the most suitable for the present invention because it is a soft material and has very high moisture permeability, excellent solvent resistance and cold resistance.

Therefore, a composition obtained by kneading polyvinyl chloride and polyurethane or a vinyl chloride-urethane copolymer,
It exhibits high moisture permeability and excellent solvent resistance, and is also cold resistant and flame retardant. Here, solvent resistance refers to non-elution property to dry cleaning solvents. but,
These polyurethanes and vinyl chloride copolymers have low heat resistance and are therefore insufficient for practical use as compositions.

Generally, the heat resistance of plasticized polyvinyl chloride compositions varies greatly depending on the type of plasticizer used. Heat-resistant plasticizers include
There are polyester-based, trimellitate-based, epoxy-based, etc. Among these, polyester plasticizers have an ester group, so they have good affinity with water molecules, are easily polymerized, and exhibit excellent solvent resistance when the average molecular weight is 6,000 or more. Polyester plasticizers include phthalic acid, adipic acid, and sebacic acid. Among them, sebacic acid is a long-chain dibasic acid, so the distance between the polar groups in the ester bond is wide, and the molecular It has a large degree of freedom and has the best compatibility with polyvinyl chloride.

Therefore, a composition obtained by kneading polyvinyl chloride and a polyester plasticizer having an average molecular weight of 6,000 or more exhibits high moisture permeability and strong solvent resistance, and also has heat resistance and flame retardancy. However, since the plasticizer is polymeric flea,
Cold resistance as a composition is insufficient.

From these facts, 3 parts of polyester plasticizer with an average molecular weight of 6000 or more per 100 parts by weight of polyvinyl chloride.
A polyvinyl chloride composition obtained by kneading 0 to 1004 parts by weight and 20 to 80 parts by weight of polyurethane or vinyl chloride copolymer exhibits high moisture permeability and excellent solvent resistance,
And heat resistant.

It has both cold resistance and flame retardancy, and is most suitable as a moisture-permeable outer covering for the flexible thermosensitive wire of the present invention. If the polyester plasticizer is less than 30 parts by weight, the moisture permeability and heat resistance will be poor, and if it is more than 100 parts by weight, the compatibility will be poor and it will be easy to bleed out. Furthermore, if the amount of polyurethane or vinyl chloride copolymer is less than 20 parts by weight, the moisture permeability and flexibility will be poor, and if it is more than 80 parts by weight, the heat resistance will be poor.

In addition, to improve the mechanical strength and heat resistance of the composition,
As polyvinyl chloride, it is desirable to use a high polymerization degree polymer having an average degree of polymerization of 1800 or more. In particular, the flexible thermosensitive electric wire of the present invention has high mechanical strength because it is placed inside a blanket such as an electric blanket, and because it is a cloth heating device, it has heat resistance and flame retardancy. This is desirable.

These properties can be easily imparted as described above.

In general, polyvinyl chloride particles have a shell (skin) of molecular aggregate particles, and are difficult to loosen even when mixed with a plasticizer and easily cause fish eyes. Skinless particles take this into consideration in the polymerization process, and have improved compatibility with plasticizers and good dispersion of polyvinyl chloride particles, making them the most suitable material for the polyvinyl chloride used in the present invention.

The polymer thermosensitive material used in the flexible thermosensitive electric wire of the present invention is:
These include polymer compositions in which resistance, capacitance, impedance, etc. have positive or negative temperature dependence, and crystalline polymer compositions that rapidly melt above the melting point and form a temperature fuse function. In addition, this flexible heat-sensitive wire is
If a plurality of built-in electrodes are used as signal lines, it becomes a temperature sensor, and if at least one is used as a heat generating line, it becomes a thermal heater.

In general, dry cleaning takes about 30 minutes per step, and tetrachlorethylene or petroleum-based solvents are used as solvents. Therefore, it is necessary for the flexible heat-sensitive wire to have a small change in heat-sensitive characteristics at least over this period of time, and to not lose its flexibility due to elution of plasticizer and the like.

A more specific example will be described below.

Example 1 FIG. 1 shows a partially exploded front view of the flexible thermosensitive electric wire of the present invention. In the figure, 1 is a core system made of polyester, 2 and 3 are ribbon-shaped electrodes made of copper alloy, 4 is a low hygroscopic polymer heat-sensitive layer made of a polyamide composition blended with a phenolic material, and 5 is a nylon 12 A layer of hydrophilic group-containing polymeric material with solvent barrier properties (thickness: 0.15111 mm)
+++), 6 is based on 1Q○ parts by weight of polyvinyl chloride,
30 parts by weight of polyurethane, polyester plasticizer [Po
1ycizerP-202J (Inu Nippon Ink Chemical Co., Ltd.)
product, average molecular weight aooo) soi parts, B a -Z
A moisture-permeable outer covering made of polyvinyl chloride containing a triple layer of n-based heat-resistant stabilizer, a total of 15 parts by weight of antimony oxide and calcium carbonate (0.4 mm thick, thicker than the polymer material layer 5) ). A moisture release test was conducted using this flexible thermosensitive wire. Moisture release test consists of impedance measurement (ZD8o) after drying a flexible thermosensitive wire at 80°C for 120 hours, saturation moisture absorption at a temperature of 43°C and relative humidity of 78%, and impedance change after leaving at a temperature of 80°C for 1 hour (ZD8o).
2w8o), and the impedance change (ΔZ
=Zw8°/ZD8o)K was evaluated. The results are shown in the table below.

Examples 2 to 5 Moisture release tests were conducted in the same manner as in Example 1, with the solvent barrier layer 5 and the moisture permeable outer layer 6 changed, and the results are shown in the table below. The plasticizer r, Paraplex G-25J, is a polyester plasticizer (average molecular weight aooo) manufactured by ROHM AND HAAS.

Further, for comparison, Conventional Examples 1 and 2 were similarly tested.

As is clear from this, the flexible thermosensitive wire of the present invention is
The moisture contained in the polymer heat-sensitive layer and its internal materials is released extremely quickly, and when used as an electric blanket, etc.
The temperature of the blanket returns to normal in a short time, and it is possible to provide a warming device that is comfortable to use.

Example 6 Using the flexible thermosensitive wire of Example 1, an immersion test in a dry cleaning solvent was conducted. The test was conducted by immersing in tetrachlorethylene for 30 minutes = drying at 60° C. for 30 minutes, and repeating it three times. Figure 2 shows a 1 m flexible thermosensitive wire.
This shows the impedance temperature characteristics per unit. 7 and 8 in the figure are the characteristics before and after the immersion test of this example. Flexible thermosensitive electric wire using a polyvinyl chloride composition kneaded with an agent...
・Compared to characteristic 9 after one immersion test in conventional example 3), there is almost no change. In addition, after the immersion test, the sample was heated to 80℃ for 2 hours.
After drying for 4 hours, the outer diameter of the flexible thermosensitive wire of the conventional example decreased by about 12% and lost its flexibility, whereas that of the present example showed almost no change.

Furthermore, the temperature fuse performance test of the flexible thermosensitive electric wire after the above immersion test was conducted (atmospheric temperature was increased from 150°C to 1°C/min).
As a result, the value of this example was 174.
It operated at ~179℃, but the conventional example operated at 183~195℃.
It operated at such high temperatures, and the temperature variations were large.

The flexible thermosensitive wires of Examples 2 to 6 were also tested in accordance with Example 6, and the results were similar.

As described above, the flexible heat-sensitive electric wire of the present invention releases water quickly, returns its heat-sensitive properties to normal in a short period of time, shows very little change in heat-sensitive properties to dry cleaning solvents, and has excellent flexibility. Don't lose it.

Effects of the Invention According to the present invention, the return to normal heat-sensitive properties due to moisture release is quick, so the characteristics of the polymer heat-sensitive material can be fully brought out, and it is flexible enough to enable dry cleaning of electric blankets, etc. We can provide sensual heat-sensitive wires.

[Brief explanation of drawings]

Figure 1 depicts a part of the flexible thermosensitive wire of the present invention! FIG. 2 is a diagram showing impedance temperature characteristics before and after a solvent immersion test for the present example and the conventional example. 2.4... Electrode, 5... Solvent barrier layer, 6... Moisture permeable jacket. Name of agent: Patent attorney Toshio Nakao and 1 other WJ
Figure 1 Figure 2 Figure 1 (C)

Claims (9)

[Claims] (1) A polymer heat-sensitive layer is provided between the pair of electrodes, and a hydrophilic group-containing polymer material layer with a barrier property against dry cleaning solvents and a moisture-permeable outer covering layer are provided around the outer peripheries of these electrodes and the polymer heat-sensitive layer. Flexible heat-sensitive electric wire with sequentially installed. (2) The flexible thermosensitive electric wire according to claim 1, wherein the hydrophilic group-containing polymeric material layer is made of polyamide. (3) The flexible thermosensitive electric wire according to claim 2, wherein the polyamide is a nylon homopolymer. (4) The flexible thermosensitive electric wire according to claim 3, wherein the nylon homopolymer is nylon 11 or nylon 12. (5) The flexible thermosensitive electric wire according to claim 1, wherein the moisture-permeable outer covering layer is made of a polyvinyl chloride composition. (6) The polyvinyl chloride composition is polyvinyl chloride 100
Based on the weight part, 30 to 100 parts by weight of a polyester plasticizer having an average molecular weight of 6,000 or more, selected from vinyl chloride-urethane copolymer, vinyl chloride-acrylic copolymer, vinyl chloride-vinyl acetate copolymer, or polyurethane. 6. The flexible thermosensitive electric wire according to claim 5, which is a composition obtained by kneading 20 to 80 parts by weight of at least one of the following. (7) The polyvinyl chloride composition contains a flame retardant and has flame retardancy with a limiting oxygen index of 25 or more.
The flexible thermosensitive electric wire according to item 6 or item 6. (8) The flexible thermosensitive electric wire according to claim 6, wherein the polyvinyl chloride is a polymer having an average degree of polymerization of 1800 or more. (9) The flexible thermosensitive electric wire according to claim 6 or 8, wherein the polyvinyl chloride is a skinless granular material.