Flexible PTC heating element and method of manufacturing the heating element

A flexible PTC heating element comprising:

• an electrode formed by printing,
• a PTC resistor formed by printing and supplied with electric power from the electrode,
• a flexible substrate composed of one of resin foam having a concave/convex shape on the surface, and a rubber material having a concave/convex shape on the surface, the flexible substrate being provided with the electrode and the PTC resistor thereon, and
• a flexible cover material covering at least the electrode and the PTC resistor and joined with the flexible substrate.

A flexible PTC heating element comprising:

• a flexible substrate having ink impermeability,
• an electrode formed from conductive paste on the flexible substrate,
• a PTC resistor formed from PTC ink and supplied with electric power from the electrode,
• a flexible cover material covering the electrode and the PTC resistor, and
• an elongation deformation portion disposed to at least one of the electrode and the PTC resistor.

A flexible PTC heating element comprising:

• an electrode formed by printing,
• a PTC resistor formed by printing and supplied with electric power from the electrode,
• a flexible substrate having the electrode and the PTC resistor formed on the surface and having adhesiveness, and
• a flexible cover material covering at least the electrode and the PTC resistor and joined with the flexible substrate, wherein
• at least one of the flexible substrate and the flexible cover material has an elongation control portion.

A method of manufacturing a flexible PTC heating element comprising steps of:

• A) filling resin at least to a deformable opening in a flexible mesh substrate,
• B) forming an electrode and a PTC resistor supplied with electric power from the electrode by printing on the flexible mesh substrate,
• C) removing the resin, and
• D) covering an entire portion with a flexible cover material.