Abstract: A UV sterilization chamber is provided to a humidifier having a water reservoir, a humidifying element and a pathway for directing water provided by the water reservoir to the humidifying element of the humidifier. The pathway is provided in a humidifier base, over which a humidifier enclosure is removably placed. The UV sterilization chamber includes a serpentine portion of the pathway and a UV radiation source positioned for illuminating the portion of the pathway with UV light. Upwardly-directed projections in the base border a perimeter of the pathway; and a downwardly-directed projection of the UV radiation source extends between the upwardly-directed projections when the enclosure is mated with the base, thereby locating the UV radiation source over the portion of the pathway. A switch disables the UV radiation source when the enclosure is removed from the base.

Abstract: An identification label changes color in an irreversible manner once put into contact with water/humidity. The label has a water-absorbable paper-based substrate having a surface on which an ink zone formed by printing of water-repellent or hydrophobic ink thereon and an opposite second surface on which a coating layer is formed. The ink zone has a color substantially identical to color of the substrate. The coating layer contains water soluble substance, which dissolves into water to form a solution that, once being absorbed by the substrate, changes the color of the substrate, the color of the solution being different from that of the substrate. A layer of adhesive is formed below the coating layer. Alternatively, the coating layer is formed on a surface of a double-sided adhesive layer and is bonded to a surface of the substrate opposite to the surface on which the ink zone is formed.

Abstract: An identification label changes color in an irreversible manner once put into contact with water/humidity. The label has a water-absorbable paper-based substrate having a surface on which an ink zone formed by printing of water-repellent or hydrophobic ink thereon and an opposite second surface on which a coating layer is formed. The ink zone has a color substantially identical to color of the substrate. The coating layer contains water soluble substance, which dissolves into water to form a solution that, once being absorbed by the substrate, changes the color of the substrate, the color of the solution being different from that of the substrate. A layer of adhesive is formed below the coating layer. Alternatively, the coating layer is formed on a surface of a double-sided adhesive layer and is bonded to a surface of the substrate opposite to the surface on which the ink zone is formed.

Abstract: The sticker contains a flat base member made of a water-permeable material, a water-resistant ink layer on a top surface of the base member, a water-soluble dye layer on a bottom surface of the base member, and an adhesive layer on a bottom surface of the dye layer for attaching the sticker to a lottery ticket. The ink layer has a graphical or text image of the same color as the base member so that the image wouldn't be visible. The dye layer has a different color from that of the base member and the ink layer. The dye layer is water-soluble so that, once it is contacted with water, it is dissolved into the water and permeates into the base member. Due to the color difference, the image of the ink layer then becomes visible.

Abstract: An identification label changes color in an irreversible manner once put into contact with water humidity. The label has a water-absorbable paper-based substrate having a surface on which an ink zone formed by printing of water-repellent or hydrophobic ink thereon and an opposite second surface on which a coating layer is formed. The ink zone has a color substantially identical to color of the substrate. The coating layer contains water soluble substance, which dissolves into water to form a solution that, once being absorbed by the substrate, changes the color of the substrate, the color of the solution being different from that of the substrate. A layer of adhesive is formed below the coating layer. Alternatively, the coating layer is formed on a surface of a double-sided adhesive layer and is bonded to a surface of the substrate opposite to the surface on which the ink zone is formed.