US Patent 7862802 Patches for teeth whitening

The present invention relates to a dry type tooth whitening patch comprising peroxide as a tooth whitening agent. In particular, disclosed is a dry type tooth whitening patch in which a peroxide is contained, as a teeth whitening agent, in a matrix type adhesive layer. The adhesive layer includes, as a base polymer thereof, a hydrophilic glass polymer which provides a strong adhesion to teeth while releasing the tooth whitening agent when hydrated on the enamel layers of teeth in the moist oral cavity. The dry type patch according to the present invention is convenient in use, as compared to wet type patches. Further, it exhibits a superior adhesion while being maintained in a state attached to the teeth for a lengthened period of time so as to assure an enough contact time between the whitening agent in the patch and stains on the teeth, thereby giving a sufficient whitening effect.