In the packaging field is the reduction of the dew point inside the packaging or container to eliminate humidity or guarantee preservation of qualities and properties of use of the product packed. Desiccant bag is an example of product absorbing humidity inside the packaging.

In physical chemistry absorption is the incorporation of a substance in one state into another of a different state (e.g. liquids being absorbed by a solid or gases being absorbed by a liquid).

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In the field of packaging protection we can use adsorbtion to define:

- the diffusion of VCI molecules inside the packaging

- the humidity attraction process from the raw material, like for example unpacked argile or silicagel

Adsorption is the adhesion of atoms, ions, biomolecules or molecules of gas, liquid, or dissolved solids to a surface.

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Bentonite is a clayey mineral made of montmorillonite, calcium or sodium. In the packaging field bentonite is used as desiccant in bags of non-woven tissue to eliminate humidity inside packagings.

Propasecard humidity indicators are cobalt chloride free.

Cobalt chloride is an inorganic compound of cobalt and chlorine, with the formula CoCl2. It is usually supplied as the hexahydrate CoCl2·6H2O, which is one of the most commonly used cobalt compounds in the laboratory. The hexahydrate is deep purple in color, whereas the anhydrous form is sky blue. A blend would be mauve. Because of the ease of the hydration/dehydration reaction, and the resulting color change, cobalt chloride is used as an indicator for water in desiccants. Niche uses include its role in organic synthesis and electroplating objects with cobalt metal. It has been classified as a Substance of very high concern by the European Chemicals Agency.

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Condensation is the change of the physical state of matter from gaseous phase into liquid phase, and is the reverse of evaporation. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition.

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Propagroup product range for humidity protection also includes a specified desiccant to be used inside container, PROPADRY.

An intermodal container or freight container is a reusable transport and storage unit for moving products and raw materials between locations or countries; the terms container or box may be used on their own within the context of shipping.

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A desiccant is a hygroscopic substance that induces or sustains a state of dryness (desiccation) in its local vicinity in a moderately well-sealed container. Commonly encountered pre-packaged desiccants are solids, and work through absorption or adsorption of water, or a combination of the two. Desiccants for specialized purposes may be in forms other than solid, and may work through other principles, such as chemical bonding of water molecules. Pre-packaged desiccant is most commonly used to remove excessive humidity that would normally degrade or even destroy products sensitive to moisture. Drierite, Silica gel, calcium sulfate, calcium chloride, montmorillonite clay, and molecular sieves are commonly used as desiccants.

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Desiccant clay is the common name to call calcium bentonite (montmorellonite), a material of natural origin and chemically inert, non-corrosive and mainly consisting of magnesium and calcium silicate aluminium.

Humidity is a term for the amount of water vapor in air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of air and water vapor, and humidity is defined in terms of the water content of this mixture, called the Absolute humidity. In everyday usage, it commonly refers to relative humidity, expressed as a percent in weather forecasts and on household humidistats; it is so called because it measures the current absolute humidity relative to the maximum. Specific humidity is a ratio of the water vapor content of the mixture to the dry air content. The water vapor content of the mixture can be measured either as mass per volume or as a partial pressure, depending on the usage.

A molecular sieve is a material containing tiny pores of a precise and uniform size that is used as an adsorbent for gases and liquids. Molecules small enough to pass through the pores are adsorbed while larger molecules are not. It is different from a common filter in that it operates on a molecular level and traps the adsorbed substance. For instance, a water molecule may be small enough to pass through the pores while larger molecules are not, so water is forced into the pores which act as a trap for the penetrating water molecules, which are retained within the pores. Because of this, they often function as a desiccant. A molecular sieve can adsorb water up to 22% of its own weight.[1] The principle of adsorption to molecular sieve particles is somewhat similar to that of size exclusion chromatography, except that without a changing solution composition, the adsorbed product remains trapped because in the absence of other molecules able to penetrate the pore and fill the space, a vacuum would be created by desorption. Often they consist of aluminosilicate minerals, clays, porous glasses, microporous charcoals, zeolites, active carbons, or synthetic compounds that have open structures through which small molecules, such as nitrogen and water can diffuse. Molecular sieves are often utilized in the petroleum industry, especially for the purification of gas streams and in the chemistry laboratory for separating compounds and drying reaction starting materials. The mercury content of natural gas is extremely harmful to the aluminium piping and other parts of the liquefaction apparatus—silica gel is used in this case. Methods for regeneration of molecular sieves include pressure change (as in oxygen concentrators), heating and purging with a carrier gas (as when used in ethanol dehydration), or heating under high vacuum. Temperatures typically used to regenerate water-adsorbed molecular sieves range from 130 °C to 250 °C

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Silica gel is most commonly encountered in everyday life as beads packed in a vapor-permeable plastic. In this form, it is used as a desiccant to control local humidity in order to avoid spoilage or degradation of some goods. Because of poisonous dopants (see below) and their very high absorption of moisture, sílica gel packets usually bear warnings for the user not to eat the contents. If consumed, the pure silica gel is unlikely to cause acute or chronic illness, but would be problematic nonetheless. Food-grade desiccant should not include any poisons which would cause long-term harm to humans if consumed in the quantities normally included with the items of food.

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In many items, moisture encourages the growth of mold and spoilage. Condensation may also damage other items like electronics and may speed the decomposition of chemicals, such as those in vitamin pills. Through the inclusion of silica gel packets, these items can be preserved longer.

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The chemical or electrochemical reaction between a material, usually a metal, and its environment that produces a deterioration of the material and its properties.

Diffusion is the volatile distribution of VCI molecules into the packaging.

PROPATECH VCI products for the protection against corrosion are free from nitrites.

Nitrites are made of a nitrogen atom and two oxygen atoms negatively charged and it can be found in some anticorrosive VCI products on the market. Its presence has to be allowed and declared from the producer.

A corrosion reaction in which the corroded metal forms an oxide; usually applied to reaction with a gas containing elemental oxygen, such as air.

Rust is a general term for a series of iron oxides. Colloquially, the term is applied to red oxides, formed by the reaction of iron and oxygen in the presence of water or air moisture. Rust generates metal corrosion.

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Transformation from a solid to a gaseous state of VCI molecules starting from the protective material (paper, film, diffusers, foams, etc...).

VCI is a Volatil Corrosion Inhibitor that can sublimate, from a solid to a gas state, and form a thin invisible layer able to neutralize corrosive agents such as: water vapour, oxygen, saline atmosphere, sulphurous gases and the most common industrial environmental pollutants present in the air.

The Volatile Corrosion Inhibitor is a chemical substance that inhibits electrochemical oxidation of metals in reaction with an oxidant such as oxygen.

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An accelerometer is an instrument able to take and/or measure acceleration.

Shockwatch labels, ShockDot and ShockWatch clips are devices containing a tube with red liquid held in suspension. When the device is subjected to an impact exceedign a specified G-level, the shock releases the highly visible red liquid into the tube.

The acceleration of gravity is an acceleration that a material undergo when it is left in free movement in the gravitation field.

A pallet is a flat transport structure that supports goods in a stable fashion while being lifted by a forklift, pallet jack, front loader or other jacking device. A pallet is the structural foundation of a unit load which allows handling and storage efficiencies. Goods or shipping containers are often placed on a pallet secured with strapping, stretch wrap or shrink wrap and shipped.

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Propack desiccant bags are certified according to DIN standards.

The Deutsches Institut für Normung (German institute for standardization, known as DIN) is a german organization for definition of standard. Founded in 1917 and named Normenausschuss der deutschen Industrie (Asociation for standards in the german industry), then has been renamed in 1926 and again in 1975. Today the official name is "DIN Deutsches Institut für Normung e. V".

Propack is certified according to the standard UNI EN ISO 9001 2008.

ISO, International organization for standardization, is the most important organization in the world for definitions of industrial and comercial standards. Its members are national organizations for standardization of 157 countries of the world.