PROPASEC

We recommend using desiccants inside your package, even in those made of VCI films, in order to improve corrosion protection.

Lab tests together with our over 40 years of experience confirm that the combination of VCI Propatech products with Propasec desiccant bags increases the effectiveness of both of them extending the protection of your goods.

Desiccant bags absorb humidity in the package, hence they reduce risk of oxidation. Still, to protect a material against corrosion, it is necessary to use a Propagroup VCI product as well.

Desiccant salt bags are made from a permeable non-woven fabric, which allows water vapour to be absorbed inside the bag itself. This non-woven fabric, in accordance with DIN 55473, can be divided into two classes depending on the amount of powder that can be released from the desiccant bag itself:

• Class A: Slight dust leakage tolerated (must not release more than 10 mg of dust per desiccant unit);

• Class B: Total dust retention (regardless of the desiccant units, the bag must not release more than 1 mg of dust).

Desiccant bags can also be manufactured with other fabrics approved for food contact, such as Tyvek.

PROPASEC desiccant bags are certified and comply with NFH 00320 / 00321 french norms and DIN 55473 german norms.  

Propagroup strongly advises not to regenerate the desiccant bags of own production "Propasec, Propasil and Propasieve" because this procedure is not recommended by the main European and international standards.

We would like to underline that, the regeneration treatment would compromise the quality characteristics, which would no longer guarantee the effectiveness of absorption capacity.

Furthermore, also the technical characteristics of the desiccant bag, particularly its mechanical strength and tightness of the external wrapping, may be damaged by this procedure.

The Desiccant Unit defines the product quantity that absorbs a minimum quantity of 6,0 g of vapour, at an air temperature of 23 ± 2 ºC and a 40% relative humidity. 

The implementation of monitoring systems offers a tangible ROI (Return On Investment) through the reduction of costs arising from damages and returns, which represents the most immediate benefit. The improvement of service quality increases customer satisfaction and strengthens corporate reputation. The devices provide objective documentation to handle complaints, facilitate the identification of unreliable logistics suppliers and allow for negotiating more favorable insurance conditions. Systematic data collection supports predictive analysis to optimize packaging, transport routes and storage methods.

Monitoring systems find strategic application in the pharmaceutical industry to maintain drug efficacy, in the food sector to preserve the cold chain, in precision electronics where shocks and vibrations can compromise delicate components. Other critical sectors include the transport of artworks, scientific instruments, medical equipment and all high-value products that require optimal transport conditions and complete documentation of their status during handling.

Desiccant bags for packaging are the most practical and flexible solution to prevent moisture circulation in enclosed spaces. Propagroup has many years of experience in the production of desiccant bags, capable of absorbing and neutralizing moisture and condensation in packaging or inside a container. Our desiccants include a wide range of products that, in addition to guaranteeing a high degree of protection, also ensure total respect for the environment, combining excellent absorption capacity with very low costs.

Clay desiccant is a material of natural origin. It is chemically inert, non-corrosive and is composed mainly of calcium and magnesium aluminium silicates. Thanks to its absorption capacity, clay reduces the dew point inside packaging, making it possible to protect the quality and properties of products against moisture attacks.

Silica gel is an excellent drying agent and is thus used as a desiccant and for local humidity control. Although its action is called "desiccant", in reality the physicochemical process whereby water vapour is removed from the air consists in an operation of adsorption: molecules of water vapour bind to the surface of the silica gel, which should not be understood as only the outer surface, but rather the total surface: silica has considerable porosity, and this means a larger total available area for the exchange of matter, that is, a fairly rapid dehumidification process. 

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).

Source: wikipedia | license

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.

Source: wikipedia | license

In the protective packaging sector we can speak of adsorption to define:

- the phenomenon of diffusion of VCI molecules in the packaging

- the process of moisture attraction by raw materials, such as clay or unpackaged silica gel

In the physical chemistry field, adsorption is generally a particular type of absorption that occurs only at the surface.

Source: wikipedia | license

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.

Source: wikipedia | license

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.

Source: wikipedia | license

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.

Source: wikipedia | license

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.

Source: wikipedia | license

Desiccant clay is the name commonly used to define calcium bentonite (montmorillonite), a naturally occurring material that is chemically inert, non-corrosive and composed mainly of calcium and magnesium aluminum silicates.

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

Source: wikipedia | license

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.

Source: wikipedia | license

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.

Source: wikipedia | license