Stretchable circuit board

1. A stretchable circuit board comprising:

a stretchable base material;

a stretchable conductive pattern formed on at least one main surface of the stretchable base material and having stretchability; and

a reinforcing base having higher rigidity than the stretchable base material, wherein

the reinforcing base reinforces the stretchable base material by being directly or indirectly laminated on the stretchable base material so as to surround a formation region of the stretchable conductive pattern in the stretchable base material in a plan view.

2. The stretchable circuit board according to claim 1 , further comprising

a draw-out wiring formed on one main surface of the reinforcing base, wherein

one end of the draw-out wiring and the stretchable conductive pattern are connected to each other, and

an external connection terminal is provided at the other end of the draw-out wiring.

3. The stretchable circuit board according to claim 2 , further comprising

a stretchable cover layer having insulating properties and stretchability, and interposed between the reinforcing base and the stretchable base material, wherein

the one end of the draw-out wiring and the stretchable conductive pattern are connected to each other through an opening hole formed in the stretchable cover layer.

4. The stretchable circuit board according to claim 2 , wherein the external connection terminal includes: a first member disposed on one surface side of the reinforcing base and the draw-out wiring; and a second member fitted into the first member via the reinforcing base, from the other surface side of the reinforcing base and the draw-out wiring.

5. The stretchable circuit board according to claim 2 , wherein

the reinforcing base includes:

a surrounding portion surrounding the formation region of the stretchable conductive pattern in the stretchable base material; and

a draw-out wiring forming portion in which the draw-out wiring is formed,

the surrounding portion is formed in a circumferentially long strip shape that surrounds the formation region of the stretchable conductive pattern in the stretchable base material, and

a width dimension of the surrounding portion is 2 mm or less.

6. The stretchable circuit board according to claim 1 , wherein at least a part of the stretchable conductive pattern is a coil wiring formed in a spiral shape.

7. The stretchable circuit board according to claim 1 , wherein the stretchable conductive pattern is an antenna pattern that functions as an antenna.

8. The stretchable circuit board according to claim 1 , further comprising a magnetic shield layer disposed to cover at least the part of the formation region of the stretchable conductive pattern in the stretchable base material in a plan view, and directly or indirectly laminated on the stretchable base material.

9. The stretchable circuit board according to claim 8 , further comprising an adhesive layer that is directly or indirectly laminated on a surface of the reinforcing base opposite to the stretchable base material side, wherein

the magnetic shield layer is interposed between the adhesive layer and the reinforcing base.

10. The stretchable circuit board according to claim 1 , further comprising an adhesive layer that is directly or indirectly laminated on a surface of the reinforcing base opposite to the stretchable base material side.

11. The stretchable circuit board according to claim 1 , wherein the reinforcing base surrounds the formation region of the stretchable conductive pattern in the stretchable base material over a range of 240 degrees or more.

12. The stretchable circuit board according to claim 11 , wherein the reinforcing base surrounds the formation region of the stretchable conductive pattern in the stretchable base material over an entire circumference of the formation region.