Claims
- 1. An article which comprises a heat-responsive sheet material and adjacent and secured to one face of the sheet material a heating element which comprises:
- (A) a laminar member composed of a material which comprises an organic polymer and electrically conductive particles dispersed in the polymer in amount sufficient to render the member electrically conductive; and
- (B) a pair of laminar flexible electrodes which (i) are connected to opposite faces of said laminar member; (ii) are substantially parallel to said laminar member; and (iii) are adapted to be connected to an external source of power to cause current to pass through said laminar member;
- said laminar member and laminar electrodes having a plurality of apertures through the thickness thereof, the apertures being of elongated closed cross-section and overlapping one another to permit at least one of the dimensions of the element in the plane thereof to be changed by a change in the shape of the apertures.
- 2. An article according to claim 1 wherein the sheet material and the heating element are secured to each other by an adhesive.
- 3. An article according to claim 2 wherein the sheet material softens on heating.
- 4. An article according to claim 3 wherein the sheet material is a polymeric material.
- 5. An article according to claim 4 wherein the sheet material is an adhesive or a mastic.
- 6. An article according to claim 4 wherein the sheet material is a heat-recoverable polymeric film.
- 7. An article according to claim 6 in the form of a heat-shrinkable sleeve.
- 8. An article according to claim 4 wherein the sheet material is a polymeric film which can be rendered heat recoverable.
- 9. An article according to claim 6 which is in the form of a heat-shrinkable sleeve with the heating element on the interior surface thereof.
- 10. An article according to claim 6 which is in the form of a heat shrinkable sleeve with the heating element on the exterior surface thereof.
- 11. An article according to claim 1 wherein the laminar member (A) has a resistivity at room temperature of at least 10 ohm.cm.
- 12. An article according to claim 1 wherein at least one of the planar dimensions of the heating element can be changed at the melting point of the polymer by a percentage which is at least 30%, based on the original dimension, without complete rupture of the electrode at any point, the dimensional change being accomodated by a change in the shape of the apertures.
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of my copending application, Ser. No. 775,882 filed Mar. 9, 1977, now U.S. Pat. No. 4,177,446, which is a continuation-in-part of may application, Ser. No. 638,440 filed Dec. 8, 1975 (now abandoned).
US Referenced Citations (11)
Foreign Referenced Citations (3)
Number |
Date |
Country |
1050386 |
Dec 1966 |
GBX |
1167551 |
Dec 1969 |
GBX |
1516874 |
Jul 1978 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
775882 |
Mar 1977 |
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Continuation in Parts (1)
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Number |
Date |
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Parent |
638440 |
Dec 1975 |
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