JP3191825B2 - PTC composition - Google Patents
PTC compositionInfo
- Publication number
- JP3191825B2 JP3191825B2 JP05959992A JP5959992A JP3191825B2 JP 3191825 B2 JP3191825 B2 JP 3191825B2 JP 05959992 A JP05959992 A JP 05959992A JP 5959992 A JP5959992 A JP 5959992A JP 3191825 B2 JP3191825 B2 JP 3191825B2
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- particle size
- heating element
- amount
- carbon black
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- Thermistors And Varistors (AREA)
- Resistance Heating (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、ＰＴＣ組成物に関す
る。更に詳しくは、高温、高電圧条件下で使用し得る面
状発熱体素子の発熱要素を構成するＰＴＣ組成物に関す
る。This invention relates to PTC compositions. More specifically, the present invention relates to a PTC composition constituting a heating element of a sheet heating element which can be used under high temperature and high voltage conditions.
【０００２】[0002]
【従来の技術】カーボンブラック、グラファイト、金属
粉末、金属メッキ粉末などの導電性粒子および熱可塑性
樹脂よりなるＰＴＣ組成物を発熱要素とし、そこに電極
を付設した面状発熱体素子が従来から知られている。し
かるに、例えば80℃、200Vといった高温、高電圧条件下
で使用可能な面状発熱体素子は未だ知られていない。そ
の理由は、高温、高電圧になる程、構成材料の劣化の速
度が速くなるためである。具体的には、初期の抵抗値
(発熱させない室温下での抵抗値)が使用時間の経過と共
に上昇し、通電したときの発熱温度が低下して、目的の
温度迄発熱しなくなるからである。2. Description of the Related Art A planar heating element in which a PTC composition comprising conductive particles such as carbon black, graphite, metal powder, and metal plating powder and a thermoplastic resin is used as a heating element and an electrode is attached thereto has been known. Have been. However, a sheet heating element which can be used under high temperature and high voltage conditions of, for example, 80 ° C. and 200 V has not been known yet. The reason is that the higher the temperature and the higher the voltage, the higher the rate of deterioration of the constituent materials. Specifically, the initial resistance value
This is because (the resistance value at room temperature at which no heat is generated) increases with the elapse of use time, the heat generation temperature when power is supplied decreases, and no heat is generated to the target temperature.
【０００３】[0003]
【発明が解決しようとする課題】本発明の目的は、例え
ば80℃、200Vといった高温、高電圧条件下で使用可能な
面状発熱体素子の発熱要素を構成するＰＴＣ組成物を提
供することにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a PTC composition constituting a heating element of a sheet heating element which can be used under high temperature and high voltage conditions of, for example, 80 ° C. and 200 V. is there.
【０００４】[0004]
【課題を解決するための手段】かかる本発明の目的は、
粒径約40〜150mμのカ−ボンブラック約5〜50容積%およ
び (1)粒径約100〜500mμの無機化合物充填剤約5〜30容積%
または (2)粒径約100〜500mμの無機化合物充填剤約5〜25容積%
と粒径約10〜50mμの無機化合物充填剤約1〜10容積%の
両者を含有し、残部が熱可塑性樹脂よりなるＰＴＣ組成
物によって達成される。SUMMARY OF THE INVENTION The object of the present invention is as follows.
About 5 to 50% by volume of carbon black having a particle size of about 40 to 150 mμ and (1) About 5 to 30% by volume of an inorganic compound filler having a particle size of about 100 to 500 μm
Or (2) about 5 to 25% by volume of an inorganic compound filler having a particle size of about 100 to 500 mμ
This is achieved by a PTC composition which contains both about 1 to 10% by volume of an inorganic compound filler having a particle size of about 10 to 50 μm, with the balance being a thermoplastic resin.
【０００５】 カ−ボンブラックとしては、粒径約40〜
150mμのものが、組成物中約5〜50容積%を占めるような
割合で用いられる。これ以上粒径の大きいものを用いて
も、必要な抵抗が得られず（下がらず）、またこれより
小さい粒径のものは、少量で低抵抗になるため、製造上
のバラツキが大きくなり、また充填量が少ないことによ
り劣化を抑えられない可能性がある。[0005] Carbon black has a particle size of about 40 to
150 mμ is used in such a proportion that it occupies about 5 to 50% by volume in the composition. Even if a particle having a larger particle size is used, the required resistance cannot be obtained (does not decrease), and if the particle has a smaller particle size, the resistance is reduced in a small amount. In addition, deterioration may not be suppressed due to a small amount of filling.
【０００６】 また、無機化合物充填剤としては、Ti
O2、Fe2O3、ZnO、SiO2、MgO、Al2O3、Cr2O3、BaSO4、Ca
CO3、Ca(OH)2、Pb3O4など任意のものを用いることがで
き、好ましくは無機酸化物充填剤が用いられる。これら
の充填剤は、約100〜500mμの粒径のものが用いられ
る。このような粒径範囲は、一緒に用いられるカ−ボン
ブラックの粒径の約３倍程度の範囲としてとらえられ
る。[0006] As an inorganic compound filler, Ti
O 2 , Fe 2 O 3 , ZnO, SiO 2 , MgO, Al 2 O 3 , Cr 2 O 3 , BaSO 4 , Ca
Any material such as CO 3 , Ca (OH) 2 , and Pb 3 O 4 can be used, and an inorganic oxide filler is preferably used. These fillers have a particle size of about 100 to 500 mμ. Such a range of particle sizes is determined by the carbon
This range is about three times the particle size of black .
【０００７】これらの粒径約100〜500mμの充填剤がそ
れだけで用いられる場合には、組成物中約5〜30容積%占
めるような割合で用いられる。これ以下の割合では、本
発明の目的とする所期の効果が得られず、一方これ以上
の割合で用いられると、それから得られるＰＴＣ面状発
熱体素子部分が強度的に脆くなり、実用性に欠けるよう
になる。When these fillers having a particle size of about 100 to 500 mm are used by themselves, they are used in such a proportion that they occupy about 5 to 30% by volume in the composition. If the ratio is lower than this, the intended effect of the present invention cannot be obtained, while if used at a ratio higher than this, the PTC planar heating element obtained therefrom becomes brittle in terms of strength and is not practical. Will be lacking.
【０００８】このような粒径範囲を有する充填剤約5〜2
5容積%と共に、それの約1/10の粒径範囲、即ち約10〜50
mμの無機化合物充填剤を約1〜10容積%併用すると、面
状発熱体の耐久発熱時間が著しく延長される。[0008] About 5 to 2 fillers having such a particle size range.
With 5% by volume, about 1/10 its size range, i.e. about 10-50
When about 1 to 10% by volume of an inorganic compound filler of mμ is used in combination, the durable heat generation time of the sheet heating element is significantly prolonged.
【０００９】 カ−ボンブラックおよび無機化合物充填
剤以外の残部は、熱可塑性樹脂から構成される。熱可塑
性樹脂としては、オレフィン系重合体、ポリエステル、
ポリアミドなど従来例と同じものが用いられるが、無水
マレイン酸グラフト化ポリエチレン、エチレン-アクリ
ル酸共重合体などの極性基を有する接着性オレフィン系
重合体が好んで用いられる。The balance other than carbon black and the inorganic compound filler is composed of a thermoplastic resin. As thermoplastic resins, olefin polymers, polyesters,
The same materials as in the conventional example such as polyamide are used, but adhesive olefin polymers having a polar group such as maleic anhydride-grafted polyethylene and ethylene-acrylic acid copolymer are preferably used.
【００１０】以上の各成分からなるＰＴＣ組成物は、加
熱オープンロールなどで混練し、混練物を圧縮プレスな
どでプレスしながら金属箔上に約0.03〜1mm程度の厚さ
で貼り合わせ、金属箔面に必要なパターンをマスキング
した後エッチングし、くし形などの電極を形成させて、
ＰＴＣ面状発熱体素子とする。得られた素子の両面に、
シリコン系あるいはアクリル系などの接着剤を用いてプ
ラスチックフィルムを貼り合わせてサンドウィッチ構造
とし、これに端子を取り付けて面状発熱体とする。これ
以外の方法によっても、面状発熱体素子および面状発熱
体を作製することができる。The PTC composition comprising the above components is kneaded with a heated open roll or the like, and the kneaded material is pressed on a metal foil while being pressed by a compression press or the like to a thickness of about 0.03 to 1 mm. After masking the required pattern on the surface, etching it, forming electrodes such as combs,
It is a PTC planar heating element. On both sides of the obtained device,
A plastic film is bonded by using a silicone-based or acrylic-based adhesive to form a sandwich structure, and terminals are attached to the sandwich structure to form a planar heating element. The planar heating element and the planar heating element can be manufactured by other methods.
【００１１】[0011]
【発明の効果】面状発熱体の使用温度域、製造過程の温
度域で不活性な、特定粒径範囲の無機化合物充填剤を多
量に充填することにより、発熱要素としてＰＴＣ組成物
を用いた面状発熱体素子の寿命を飛躍的に高めることが
でき、これ迄実用化されていなかった例えば80℃、200V
などといった高温、高電圧条件下での使用にも耐え得る
面状発熱体素子の提供を可能とさせる。According to the present invention, the PTC composition is used as a heat-generating element by filling a large amount of an inorganic compound filler having a specific particle size range, which is inactive in the temperature range in which the sheet heating element is used and in the manufacturing process. The life of the planar heating element can be drastically increased, for example, 80 ° C, 200V
Thus, it is possible to provide a planar heating element that can withstand use under high temperature and high voltage conditions.
【００１２】[0012]
【実施例】次に、実施例について本発明を説明する。Next, the present invention will be described by way of examples.
【００１３】実施例１ カーボンブラック 19.6容積% (中部カーボン製品HTC#20；平均粒径120mμ) 酸化チタン 20 容積% (石原産業製品タイペークA-100；平均粒径150mμ) 接着性中密度ポリエチレン 残部 (三井石油化学製品アドマーNE060) 以上の各成分を加熱オープンロールで混練し、この混練
物を圧縮プレスでプレスしながら、金属箔(50mm×200mm
×18μm)上に、20×190mmの面積、0.2mmの厚さで貼り合
わせた。Example 1 Carbon black 19.6% by volume (Central carbon product HTC # 20; average particle size 120mμ) Titanium oxide 20% by volume (Ishihara Sangyo product TYPAKE A-100; average particle size 150mμ) Adhesive medium density polyethylene Remainder ( Mitsui Petrochemical Admar NE060) Knead the above components with a heated open roll, press the kneaded product with a compression press, and use a metal foil (50 mm x 200 mm
× 18 μm) with an area of 20 × 190 mm and a thickness of 0.2 mm.
【００１４】この貼り合わされた金属箔について、混練
物貼合部分に必要なパターンをマスキングした後、塩化
第２鉄水溶液をエッチング剤とするエッチングを行い、
幅が1mm、間隔が2mmのくし形電極を形成させて、ＰＴＣ
面状発熱体素子を得た。After the necessary pattern is masked on the bonded metal foil at the bonded portion of the kneaded material, etching is performed using an aqueous ferric chloride solution as an etching agent.
PTC with 1mm width and 2mm spacing
A planar heating element was obtained.
【００１５】得られたＰＴＣ面状発熱体素子の両面に、
シリコン系接着剤を用いてポリエステルフィルム(厚さ1
00μm)を貼り合わせてサンドウィッチ絶縁構造とし、端
子を取り付けて発熱体とした。この発熱体について、抵
抗値および発熱耐久時間(230Vを印加し、発熱させたと
きの発熱温度が初期温度から80℃以下に低下する迄の時
間)を測定した。On both sides of the obtained PTC planar heating element,
Polyester film (thickness 1
00 μm) to form a sandwich insulating structure, and terminals were attached to form a heating element. With respect to this heating element, the resistance value and the heat generation endurance time (the time required for the heat generation temperature when 230 V was applied to generate heat to decrease from the initial temperature to 80 ° C. or less) were measured.
【００１６】実施例２ 実施例１において、他の酸化チタン(石原産業製品タイ
ペークCR-58；平均粒径250mμ)を同量用い、カーボンブ
ラック量を20容積%に変更した。Example 2 In Example 1, the same amount of other titanium oxide (Ishihara Sangyo product, Taipaque CR-58; average particle size 250 mμ) was used, and the amount of carbon black was changed to 20% by volume.
【００１７】実施例３ 実施例１において、他の酸化チタン(石原産業製品タイ
ペークTY-50；平均粒径400mμ)を同量用い、カーボンブ
ラック量を19容積%に変更した。Example 3 In Example 1, the same amount of other titanium oxides (Ishihara Sangyo product, Taipaek TY-50; average particle size: 400 mμ) was used, and the amount of carbon black was changed to 19% by volume.
【００１８】実施例４ 実施例１において、酸化チタン量を10容積%に、またカ
ーボンブラック量を19.5容積%にそれぞれ変更した。Example 4 In Example 1, the amount of titanium oxide was changed to 10% by volume, and the amount of carbon black was changed to 19.5% by volume.
【００１９】実施例５ 実施例１において、酸化チタン量を7容積%に、またカー
ボンブラック量を21容積%にそれぞれ変更した。Example 5 In Example 1, the amount of titanium oxide was changed to 7% by volume, and the amount of carbon black was changed to 21% by volume.
【００２０】実施例６ 実施例１において、酸化チタンの代わりに酸化鉄(堺化
学製品ベンガラ#401；平均粒径200mμ)を同量用い、カ
ーボンブラック量を20.8容積%に変更した。Example 6 In Example 1, the same amount of iron oxide (Bengara # 401, average particle diameter 200 mμ) was used instead of titanium oxide, and the amount of carbon black was changed to 20.8% by volume.
【００２１】実施例７ 実施例１において、酸化チタンの代わりにアルミナ(石
津製薬製品；平均粒径200mμ)を同量用い、カーボンブ
ラック量を21容積%に変更した。Example 7 In Example 1, the same amount of alumina (Ishizu Pharmaceutical; average particle size: 200 μm) was used instead of titanium oxide, and the amount of carbon black was changed to 21% by volume.
【００２２】比較例１ 実施例１において、酸化チタン量を３５容積％に、また
カーボンブラック量を２０容積％にそれぞれ変更した。
得られた発熱体は、ＰＴＣ面状発熱体素子部分が強度的
に脆く、発熱耐久時間の測定ができなかった。 Comparative Example 1 In Example 1, the amount of titanium oxide was changed to 35% by volume, and the amount of carbon black was changed to 20% by volume.
In the obtained heating element, the PTC planar heating element part was brittle in terms of strength, and it was not possible to measure the heat generation durability time .
【００２３】比較例２ 実施例１において、酸化チタン量を3容積%に、またカー
ボンブラック量を20.5容積%にそれぞれ変更した。Comparative Example 2 In Example 1, the amount of titanium oxide was changed to 3% by volume, and the amount of carbon black was changed to 20.5% by volume.
【００２４】比較例３ 実施例１において、酸化チタンを用いずに、カーボンブ
ラック量を22容積%に変更した。Comparative Example 3 In Example 1, the amount of carbon black was changed to 22% by volume without using titanium oxide.
【００２５】比較例４ 実施例１において、酸化チタンの代わりにアルミナ(昭
和電工製品AL-24；平均粒径2μ)を同量用い、カーボン
ブラック量を19.2容積%に変更した。Comparative Example 4 In Example 1, the same amount of alumina (AL-24, Showa Denko; average particle size: 2 μm) was used instead of titanium oxide, and the amount of carbon black was changed to 19.2% by volume.
【００２６】以上の各実施例および比較例での測定結果
は、次の表１に示される。 表１ 例 抵抗値(Ω) 初期温度(℃) 発熱耐久時間(hrs) 実施例１ 3.7×102 88 2000 〃 ２ 3.2×102 89 1500 〃 ３ 3.4×102 89 1000 〃 ４ 3.5×102 89 1200 〃 ５ 3.8×102 87 900 〃 ６ 2.7×102 92 1700 〃 ７ 2.9×102 90 2800 比較例２ 3.2×102 90 500 〃 ３ 3.1×102 90 500 〃 ４ 3.1×102 90 600The results of the measurements in the above Examples and Comparative Examples are shown in Table 1 below. Table 1 Example Resistance value (Ω) Initial temperature (° C) Heat generation endurance time (hrs) Example 1 3.7 × 10 2 88 2000 〃 2 3.2 × 10 2 89 1500 ３ 3 3.4 × 10 2 89 1000 〃 4 3.5 × 10 2 89 1200 ５ 5 3.8 × 10 2 87 900 ６ 6 2.7 × 10 2 92 1700 ７ 7 2.9 × 10 2 90 2800 Comparative Example 2 3.2 × 10 2 90 500 ３ 3 3.1 × 10 2 90 500 ４ 4 3.1 × 10 2 90 600
【００２７】比較例５ 実施例１において、酸化チタンの代わりに酸化けい素
(日本アエロジル製品アエロジルR972；平均粒径16mμ)
を同量用い、カーボンブラック量を25.2容積%に変更し
た。Comparative Example 5 In Example 1, silicon oxide was used instead of titanium oxide.
(Japan Aerosil product Aerosil R972; average particle size 16mμ)
And the amount of carbon black was changed to 25.2% by volume.
【００２８】実施例８ 実施例１において、更に比較例５で用いられた酸化けい
素3容積%を加え、カーボンブラック量を23容積%に変更
した。Example 8 In Example 1, 3% by volume of the silicon oxide used in Comparative Example 5 was added, and the amount of carbon black was changed to 23% by volume.
【００２９】実施例９ 実施例１において、更に比較例５で用いられた酸化けい
素7容積%を加え、酸化チタン量を10容積%に、またカー
ボンブラック量を21容積%にそれぞれ変更した。Example 9 In Example 1, 7% by volume of the silicon oxide used in Comparative Example 5 was further added to change the amount of titanium oxide to 10% by volume and the amount of carbon black to 21% by volume.
【００３０】以上の比較例５および実施例８〜９でそれ
ぞれ得られたＰＴＣ面状発熱体について、実施例１と同
様に抵抗値、初期温度および発熱耐久時間を測定する
と、次の表２に示されるような結果が得られた。 表２ 例 抵抗値(Ω) 初期温度(℃) 発熱耐久時間(hrs) 比較例５ 3.2×102 90 500 実施例８ 2.8×102 92 3000 〃 ９ 2.7×102 92 2500With respect to the PTC sheet heating elements obtained in Comparative Example 5 and Examples 8 to 9, respectively, the resistance value, initial temperature, and heat endurance time were measured in the same manner as in Example 1. The results as shown were obtained. Table 2 Example Resistance value (Ω) Initial temperature (° C) Heating endurance time (hrs) Comparative example 5 3.2 × 10 2 90 500 Example 8 2.8 × 10 2 92 3000 ９ 9 2.7 × 10 2 92 2500
フロントページの続き (56)参考文献 特開 昭56−161464（ＪＰ，Ａ) 特開 平１−213977（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H01C 7/02 H05B 3/14 Continuation of the front page (56) References JP-A-56-16164 (JP, A) JP-A-1-213977 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) H01C 7 / 02 H05B 3/14
Claims (3)
5〜50容積%および粒径約100〜500mμの無機化合物充填
剤約5〜30容積%を含有し、残部が熱可塑性樹脂よりなる
ＰＴＣ組成物。A carbon black having a particle size of about 40 to 150 mμ.
A PTC composition comprising 5 to 50% by volume and about 5 to 30% by volume of an inorganic compound filler having a particle size of about 100 to 500 mμ, and the balance being a thermoplastic resin.
5〜50容積%、粒径約100〜500mμの無機化合物充填剤約5
〜25容積%および粒径約10〜50mμの無機化合物充填剤約
1〜10容積%を含有し、残部が熱可塑性樹脂よりなるＰＴ
Ｃ組成物。2. Carbon black having a particle size of about 40 to 150 mμ.
5 to 50% by volume, particle size about 100 to 500 mμ inorganic compound filler about 5
~ 25% by volume and particle size about 10 ~ 50mμ inorganic compound filler
PT containing 1 to 10% by volume, the balance being a thermoplastic resin
C composition.
発熱要素として用いた面状発熱体素子。3. A planar heating element using the PTC composition according to claim 1 or 2 as a heating element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05959992A JP3191825B2 (en) | 1992-02-14 | 1992-02-14 | PTC composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05959992A JP3191825B2 (en) | 1992-02-14 | 1992-02-14 | PTC composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05226112A JPH05226112A (en) | 1993-09-03 |
| JP3191825B2 true JP3191825B2 (en) | 2001-07-23 |
Family
ID=13117879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05959992A Expired - Lifetime JP3191825B2 (en) | 1992-02-14 | 1992-02-14 | PTC composition |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3191825B2 (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5691689A (en) * | 1995-08-11 | 1997-11-25 | Eaton Corporation | Electrical circuit protection devices comprising PTC conductive liquid crystal polymer compositions |
| AU3774701A (en) * | 2000-03-02 | 2001-09-12 | Lg Cable Ltd. | Ptc conductive polymer compositions, method of controlling the same and electrical device containing the same |
| KR100454732B1 (en) * | 2001-08-25 | 2004-11-05 | 엘지전선 주식회사 | Conductive polymers having a positive temperature coefficient, method for controlling the positive temperature coefficient property of this polymers and electrical devices containing this polymers |
| KR100436581B1 (en) * | 2001-11-10 | 2004-06-19 | 엘지전선 주식회사 | PTC Device Manufacturing Method With Ingredient Of Uniform Specific Property |
| KR100436580B1 (en) * | 2001-11-10 | 2004-06-19 | 엘지전선 주식회사 | PTC Device Manufacturing Method With Ingredient Of Excellent Resistance Repair Specific Property |
| KR100436578B1 (en) * | 2001-11-10 | 2004-06-19 | 엘지전선 주식회사 | PTC Device Manufacturing Method For Lithium Ion Battery Protecting And A PTC Device For Lithium Ion Battery Protecting Thereof |
| KR100436579B1 (en) * | 2001-11-10 | 2004-06-19 | 엘지전선 주식회사 | PTC Device Manufacturing Method With Excellent Resistance Repair Specific Property And PTC Device Thereof |
| CN104575888B (en) * | 2015-01-28 | 2017-10-13 | 深圳中科四合科技有限公司 | A kind of macromolecule composite pressure-sensitive material and preparation method thereof |
-
1992
- 1992-02-14 JP JP05959992A patent/JP3191825B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05226112A (en) | 1993-09-03 |
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