US Patent 8066133 Synthetic resin cap, closing device, and container-packed beverage

The present invention provides a synthetic resin cap comprising: a cap body (4) having a top plate portion (2) and a cylinder portion (3) hanging from a circumferential edge portion (2b) thereof; an annular inside seal projection (12) to be fitted to a container mouth portion (21); a connector portion (15) formed between the top plate portion (2) and the inside seal projection (12); and an outside thin wall portion (16) formed on the top plate portion (2), and provides a closing device using thereof, and a container-packed beverage.