Abstract: A method of detecting the defective portion of sealing comprising injecting into a moisture-tight container or package having a sealed portion a detection liquor consisting essentially of a colored liquid organic compound small in surface tension and high in permeability into small clearances. The defective portion of sealing is readily detected by exudation of the detection liquor outside the moisture-tight container.

Abstract: This invention relates to a device that may be inserted into the soil of a potted plant for the purpose of determining the soil moisture content thereof. The device employs a moisture sensitive signalling element and a tube-shaped humidity chamber which provides means for establishing an equilibrium condition between the moisture content of the soil and the moisture content of the air surrounding the signalling element, thereby providing an accurate indicator of soil moisture content.

Abstract: A device for determining the ion concentration of certain substances, or mixtures of substances, in swimming pool water by admixture of color forming chemical reagents comprising measuring containers and at least one reference container combined to form a row of containers which have a common side wall. An indicating screen with a plurality of fixed, differently tinted indicating windows associated with the individual containers and distributed over the height of the containers is arranged in front of the common side wall, and the indicating windows associated with the reference container or containers are provided with a standard coloration relating to that formed by the color forming reagents.

Abstract: An ink composition is provided which is suitable for use on plastic, bare metal, for example, tinplate or aluminum as well as on such metals having organic coatings applied to surfaces thereof. The inks are suitable for use in contact printers or in jet ink printing techniques and apparatus. The ink compositions are thermotropic, i.e. they change color in the presence of water or steam at elevated temperature and are useful as sterilization or pasteurization indicators. The inks comprise essentially a binder resin component, or mixture of such resin components, an alcohol solvent and a combination of dyes which produce a visible and permanent color change in the presence of water or steam at elevated temperatures.

Abstract: A thermally-responsive indicating device comprising a housing which defines a cavity therein, an indicating means in said cavity, a biasing means in said cavity, and a class of nitrogen-containing organic locking means in said cavity, wherein said locking means is adapted to fuse at a predetermined temperature.

Abstract: A method of detecting an excessive temperature at electrical wiring devices and detector for indicating by means of a color change an electrical failure at a wiring device which failure results in an excessive temperature increase.

Abstract: An oxygen indicator comprising at least one dyestuff, at least one alkaline substance and at least one reducing agent is disclosed.

Abstract: A thaw-indicating device that is visibly positioned in a package of frozen food so to warn a consumer if the food item has ever been subjected to being thawed, and thus being spoiled even if refrozen subsequently; the device consisting of a transparent plastic capsule having a sealed singular compartment in one end of which there is a colorless, clear, frozen ice and in the other end of which there is a powdered dye that is soluble in water, so that if the ice melts into water due to thawing temperatures the entire interior of the capsule is visibly colored.

Abstract: An indicator device for use as a time indicator or a time-temperature indicator. A container is provided for housing a frangible capsule and a porous carrier. A vapor generating chemical is enclosed in the capsule. A mixture, including a second chemical, a pH change responsive indicator, and a gel forming agent are impregnated in the porous carrier. The pH of the vapor is different from the second chemical. A gel is formed from the mixture and provides uniform dispersion of the second chemical and the indicator throughout the porous carrier, as well as provides an impedance to the vapor as it moves through the porous carrier. The device is thus useful as an elapsed time indicator for certain temperature ranges as well as a time-temperature indicator for wider temperature ranges.