Sorbead India is the country’s most efficient company providing the costumers with desiccants and absorbers to prevent spoilage of goods from moisture. They also offer humidity indicating cards. These cards are unique cards on which a moisture-sensitive chemical is impregnated such that it will change color when the indicated relative humidity is exceeded. It is basically a blotting paper impregnated with cobalt (II) chloride base or copper (II) chloride base.
It is an inexpensive way to measure relative humidity levels inside sealed packages. They are available in many sizes and used in many applications. A common humidity indicator card changes color from blue to pink. The humidity indicator cards are safe to use in packing and shipping of many materials.
Humidity Indicator Cards are printed with moisture sensitive spots that respond to various levels of humidity with aevident color transform. They are used inside vacuum sealed moisture barrier bags to monitor the interior humidity conditions.
Humidity indicator cards are impregnated with a solution of cobalt chloride that has been carefully mixed to change color from blue through various shades of magenta – red, to a pink. These cards are not accurate indicators. They show the maximum possible humidity in a container. Humidity Indicator Cards reveal at a glance if moisture within sealed containers or closed spaces is at an acceptable level. They assist in monitoring desiccant activity and are ideal for use with desiccants in any application where moisture control is vital. The color change from blue to pink (cobalt cards) or brown to green (cobalt-free cards) indicates an unsealed container and/or damaging level of humidity. Cobalt-free Humidity Indicator Cards do not contain heavy metals.