JPS6295804A - Polymer thermosensor - 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 (Industrial Field of Application) The present invention relates to a polymer-sensitive material comprising a specific polyamide resin composition. In particular, the present invention relates to a material that has improved resistance value in direct current or impedance behavior in alternating current with respect to temperature of a heat-sensitive material in a device that performs thermal control using electrical components as one control factor.

(Prior Art) The use of polymeric materials that exhibit high electrical properties depending on humidity, such as polyvinyl chloride and polyamide, as heat-sensitive elements has been known for some time, as seen in electronic blankets, electric carpets, and the like.

Examples of heat-sensitive material elements include direct current volume resistivity, specific dielectric constant, and volume specific impedance, and one or more of these can be controlled in combination. Therefore, the characteristics required for a heat-sensitive element are as follows:
It has a large rate of change in electrical properties due to temperature, a small change in electrical properties due to moisture absorption, and is stable with no electrical changes over time due to heat cycles.

Until now, in order to make this type of material compatible with the above-mentioned organic polymer materials, ion conductive substances such as surfactants were added as additives (Japanese Patent Publication No. 35-14175).
, copper halides, which easily dissociate into ions, were added. (Unexamined Japanese Patent Publication No. 56-39 (Problem to be Solved by the Invention)) However, since the conductive carrier of these compositions is naturally an ionic substance, it causes polarization when a DC electric field is applied.
This causes a large change in impedance over time,
In addition, the former in particular has poor heat resistance, so it could not be used as a temperature sensor for a thermal heater as described below.

Therefore, as a result of intensive studies to solve some of the above-mentioned practical problems, the present invention has created a heat-sensitive material that satisfies the above-mentioned performance requirements by combining a specific polyamide resin and a specific additive (q The present invention was achieved based on this discovery.

(Means for Solving the Problems) That is, the present invention provides a polyamide resin in which the number of amide groups per 100 carbon atoms is 14 or less, and rubidium halide is blended with 0.1 part by weight or more, io, or less by weight. It is a polymer thermosensitive body made of a composition.

The polyamide resin used in the present invention is a homopolyamide or copolyamide whose main component is lactam or ω-aminocarboxylic acid represented by nylon 6, nylon 11, nylon 12, nylon 6.6, nylon 6.10. These include homopolyamides and copolyamides whose main components are diamines such as nylon 6 and 12, and dicarboxylic acids.

Also included are polyneedleamide, polyesteramide, etc., which are copolymers of nylon heptamers and heptanones other than nylon heptamers.

The addition of rubidium halide, which is an additional component of the polyamide composition for heat-sensitive elements in the present invention, is from 0.1 to 10.0 parts by weight, preferably from 0.2 parts by weight to the polyamide resin. 5.0 parts by weight is appropriate;
Below 0.1 car M part, the change in electrical properties is not sufficient and 1
If it exceeds 0.0 part by weight, changes in electrical properties will not improve any further and mechanical properties will deteriorate.

Among the rubidium halides, rubidium iodide is preferred because its electrical properties change largely with temperature and its water absorption rate is low, followed by rubidium bromide and rubidium chloride.

The method of adding rubidium halide to the polyamide resin is not particularly limited, and can be added during the polyamide polymerization step, mechanically mixing the polyamide powder and JX rubidium halogenide, or using an extruder after mixing with the polyamide pellet. Any method can be used, such as melt-kneading.

The polyamide composition containing halogenated rubidium cum is usually further formed into a sheet or a line to form a heat-sensitive element.

(Effects of the Invention) According to the heat-sensitive element made of the heat-sensitive material of the present invention, the rate of change in electrical properties with respect to temperature is extremely large, and like a surfactant, it may bleed out or deteriorate over time. Because it does not change, it has excellent electrical stability. Furthermore, it does not corrode metal wires or metal foils made of aluminum, copper, etc. used for signal conductors, has excellent heat resistance, and has advantages such as easy cross-contamination with polyamide resin and cesium halide. .

(Example) The present invention will be explained in detail below.

Example 1 1 part by weight of rubidium fluoride was triblended with 100 parts by weight of nylon 12 pellets (Diamid L1901 manufactured by Daicel-Hüls), then melt-kneaded using an extruder and pelletized using a pelletizer. did. Using this pellet, compression molding was performed at 220°C.
A 5 mm sheet was created. The dielectric constant (ε') and dielectric loss factor (ε') of this sheet at 110 Hz were determined at 30°C.
was measured at 70°C. Electrical properties during alternating current, such as impedance, can be known from the ε-value and ε' value. It is also possible to estimate the resistance at direct current from the ε'' value.Zunawara ε' / ε'70℃ 30℃・The larger the ε°°/ε'', the better the heat sensitive material is at 70℃.
The temperature is 30℃. Furthermore, this sheet was left in air at a humidity of 60% and a temperature of 27° C. for one week, and the moisture content was measured.

The lower the water absorption rate, the more stable the electrical properties can be maintained. These results are shown in the table.

Example 2 A sheet was prepared in exactly the same manner as in Example 1 except that cesium bromide was used instead of rubidium iodide. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Example 3 A sheet was prepared in exactly the same manner as in Example 1 except that rubidium fluoride was used instead of rhodium iodide. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Example 4 A sheet was prepared in exactly the same manner as in Example 1 except that rubidium fluoride was used instead of rubidium iodide. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Example 5 Nylon 6.1 was used instead of nylon 12 in Example 1.
A sheet was prepared in exactly the same manner as in Example 1, except that Example 1 was used. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Example 6 In Example 1, polyamide elastomer (Diamide PAE-[manufactured by Daicel Huels) was used instead of nylon 12.
A sheet was prepared in exactly the same manner as in Example 1 except for using E40L). The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Comparative Example 1 A sheet was prepared in exactly the same manner as in Example 1 except that rubidium iodide was not added. The dielectric constant, dielectric loss factor, and water absorption rate of this sheet are shown in Table 1.Comparative Example 2 A sheet was prepared in exactly the same manner as in Example 5 except that rubidium iodide was not used in Example 5. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Comparative Example 3 A sheet was prepared in exactly the same manner as in Example 6 except that rubidium iodide was not used in Example 6. The table shows the dielectric constant, dielectric loss rate, and water absorption rate of this sheet.

Patent applicant Daicel-Hüls K.K. Procedures
Amendment (spontaneous) January 22, 1988 Commissioner of the Japan Patent Office Kuro 1) Akio Yu 1, Indication of the case Japanese Patent Application No. 1983-235321 2, Name of the invention Polymer thermosensitive body 3, Person making the amendment Relationship to the incident Patent applicant address: 3-8-1 Kasumigaseki, Chiyoda-ku, Tokyo
Name: Daicel-Hüls K.K. Representative: Akinori Shigaki - 4. Subject of amendment: Column 5, Detailed explanation of Meijam's invention. Contents of amendment: (1) Changed "ε-" on page 6, line 8 of the specification to 1ε' ” is corrected.

(2) "Noiron 6, 12" on page 7, lines 12-13 of the same book.
Correct 1 to [Copolymerized Nylon 12].

(3) In the table on page 9 of the same page, the types of nylon in Example 5 and Comparative Example 2, "nylon 6 and 12", have been corrected to "copolymerized nylon 12".

Claims (1)

[Claims] 0.1 part by weight or more of rubidium halide in a polyamide resin having 14 or less amide groups per 100 carbon atoms 1
A polymeric temperature sensitive body comprising a polyamide composition containing 0.0 part by weight or less.