This article will discuss on the differences between silica gel packets, and what features make them distinct from one another. Basically, silica gel packets are small sachets containing silica, iron particles (also called "oxidation") and water. Clay also forms a part of the package, which makes the package waterproof and more suitable for shipping.
Silica gel packets are mainly used in the printing industry to absorb moisture and prevent color fading. This is why they are mostly used as color separators during the printing process. As moisture absorbs moisture, the silica gel will bind to the moisture and prevent it from coming out. So by the time the print comes out, the moisture is already dried up and you don't have to spend money on ink refill.
Silica gels have the highest absorption capacity among all the materials used for packaging. This means silica gel can absorb moisture from air and moisture in the packaging itself. Due to this property, silica gel packets are good choices when you need to absorb excess moisture to prevent electronic goods from swelling during shipping. Moreover, silica gel has the lowest re-staging index (returns to manufacturing after usage). This means you get more silica gel for your money.
A related property that silica gel shares with many other substances is its ability to prevent relative humidity (RHR) from increasing. Relative humidity (RHR) is the level of moisture in the air relative to the air humidity. Low relative humidity helps keep electronic goods cool during shipping. If there is too much moisture in the air, however, they get very warm which can shorten the life of the product. The longer the time they spend in the environment, the more expensive they become.
Using silica gel as a desiccant in packaging means you get twice the amount of RHR. You also get protection against the effects of UV radiation and therefore your food items remain fresh for a longer period of time. Packaging with silica gel also reduces or eliminates the need for thermal dyes in packaging of food items.
Another benefit of packaging with silica gel is that it absorbs oxygen very well. Many packaging with silica gel products are called "iron fillings" because they absorb iron ions or ferrous ions. These include but are not limited to ferrous disc, ferricyanide, ferrous lead, ferrous phosphate, ferrous thioglycolate and calcium thioglycolate. Depending on the type of material, the absorption rate could be lower or higher.
Silica gel packets are also excellent as oxygen absorbers. Because silica gel has the property to refract light, it is an excellent absorbent and can reduce the amount of energetic molecules that pass through and enter the environment. As a result, the silica gel packets are considered non-toxic and bio-degradable. In fact, they have been in use since the 1950's in the manufacture of non-toxic aerosols and fire retardants.
A silica gel packet could be an excellent moisture or heat proofing measure especially where a product requires a tight seal or to retain moisture in storage. For example, many vacuum cleaners require a tight seal to prevent moisture or movement. Some manufacturers produce products that have small silica particles that can be used on a damp cloth to remove the moisture from carpeting or upholstery to improve its performance and lifespan. This kind of moisture indicator is ideal for areas such as the attic where humidity levels may fluctuate due to climate conditions or on boats where condensation from the seawater may gather on the boat surfaces and damage the upholstery.
Another application for silica gel is the manufacturing industry. It has excellent thermal conductivity properties that ensure that thermal insulation materials, such as fiberboard or laminated cabinets, are effective in containing heat. It also ensures that temperature cycles are maintained at appropriate levels. It is used in refrigeration systems to maintain or warn users when the coolant levels drop below a certain point and the temperatures start to increase. The silica gel in the refrigerant prevents damage to expensive equipment by maintaining the correct operating temperatures.
In compressed air systems, silica gel beads are packed with air to avoid moisture buildup in the system. It helps reduce condensation in cooling chambers. When compressed air systems are serviced, silica gel beads are blown into the system and help remove moisture that accumulates. They also help in eliminating or muffling noises associated with system failure, particularly when there are no leaks in sealing devices and ductwork.
In case of a desiccant, silica gel is used as a lubricant between the interior surface of the desiccant bag and the external surface of the unit. This reduces friction and reduces the boiling point of the liquid desiccant. As a silica gel coating on metal surfaces, the amorphous form can effectively prevent corrosion and increase the life span of vehicles, engines and other mechanical parts. It also improves brake and handling performance. Further, it increases the lifespan of electrical parts, like transformers, fuses and relays.
