Patent ID: 7780268

Claim:
A liquid transport apparatus comprising: a substrate having an insulating surface; a plurality of liquid transport channels which are disposed on the insulating surface of the substrate and in each of which a conductive liquid is transported; a plurality of electrodes disposed on the insulating surface of the substrate in regions corresponding to respective ones of the liquid transport channels; a plurality of wiring portions each having a terminal at an end thereof, and each wiring portion coupled to the surface of a corresponding one of the electrodes and extending along the insulating surface of the substrate; a first insulating layer which is disposed so as to cover the plurality of electrodes on the insulating surface of the substrate and in which a wetting angle with respect to the conductive liquid changes according to an electrical potential difference between the conductive liquid and the electrodes; a second insulating layer which is disposed so as to cover the plurality of wiring portions on the insulating surface of the substrate and which is disposed in contact with the first insulating layer; and a potential applying unit which applies an electric potential to each of the plurality of electrodes through each terminal provided on the wiring portions, wherein, when the electrical potential difference between the conductive liquid and the electrodes is less than a predetermined electrical potential difference, the wetting angle of the first insulating layer with respect to the conductive liquid is larger than the wetting angle of the second insulating layer with respect to the conductive liquid.