| abstract |
Excellent adhesion to electrode elements, and less deterioration in adhesion and adhesion to electrode elements and targets even when moisture such as sweat or moisture is absorbed, and has optimal adhesion to the skin surface and damages the skin when peeling, etc. It is an object of the present invention to provide a hydrogel that does not give any effect. As a hydrogel (1) having a laminated structure of layer A (10) and layer B (20), layer A (10) contains a monomer-derived component, water, a moisturizer, a water-insoluble polymer having adhesiveness, and an amphiphilic polymer. The water-insoluble polymer is contained 3 to 20% by weight based on the total amount of the layer A, the amphiphilic polymer is polyvinyl alcohol having a saponification degree of 50 to 75%, and 0.05 to 5% by weight based on the total amount of the A layer And, in the B layer 20, a monomer-derived component, water, and a moisturizing agent are included, and the water-insoluble polymer and polyvinyl alcohol having adhesiveness are not substantially included, and the amount of water relative to the total amount of the B layer is the A layer. It is characterized in that it is ±10% by weight of the amount of water relative to the total amount, and the amount of the moisturizer relative to the total amount of the layer B is ±10% by weight of the amount of the moisturizer relative to the total amount of the layer A. |