1. A desiccant comprising: (a) a hygroscopic composition consisting of at least 70% by weight of magnesium chloride and up to 30% by weight of one or more natural active minerals; and (b) a sealed, vapor-permeable pouch enclosing said composition, the pouch comprising a laminated multi-layer structure having an outer layer of polyethylene terephthalate (PET) and an inner layer of Dutech or Dutchess paper; wherein the desiccant pouch exhibits: (i) a moisture absorption capacity of at least 130% of its dry weight at 50°C and 95% relative humidity over 48 days; and (ii) (ii) a moisture retention of at least 96% when exposed to 80°C and 30% relative humidity for 24 hours.

2. The desiccant pouch of claim 1, wherein the natural active minerals comprise one or more selected from bentonite, attapulgite, zeolite, or natural clays.

3. The desiccant pouch of claim 1, wherein the pouch is ultrasonically heat-sealed to prevent leakage of the desiccant material and ensure mechanical integrity under thermal cycling conditions; wherein the pouch is shaped as a flat rectangular sachet or in a customized form adapted to specific automotive components; wherein the desiccant pouch is integrated into a battery pack or sealed electronic module to extend component reliability in high-humidity environments.

4. The desiccant pouch of claim 1, wherein the laminated structure provides water vapor permeability while remaining resistant to tearing and deformation at temperatures up to 85°C.

5. Use of the desiccant pouch as claimed in any one of claims 1 to 4 in an automotive assembly selected from headlamps, electronic control units (ECUs), sensors, battery packs, or cabin interiors, wherein the desiccant provides long-term moisture absorption and controlled thermal desorption; wherein the desiccant pouch is positioned within an automotive lighting unit to prevent internal fogging or condensation.

6. A method of manufacturing a desiccant pouch, the method comprising: (a) mixing magnesium chloride with atleast one or more natural active minerals to form a hygroscopic blend; (b) forming individual sachets of the blend in units ranging from 10 to 20 grams; (c) enclosing the blend in a laminated multi-layer pouch comprising PET and Dutech laminated paper or Dutchess paper; (d) heat-sealing the edges of the pouch ultrasonically; and (e) storing the sealed pouches under vacuum or in airtight packaging to prevent premature moisture absorption.

7. The method of claim 6, wherein the pouch further includes one or more anti-caking agents blended into the composition to enhance flowability during sachet formation.

8. The method of claim 6, wherein the ultrasonic sealing temperature is maintained in the range of 120°C to 160°C to ensure seam integrity under high-temperature automotive conditions.

9. The method of claim 6, wherein the outer PET layer of the pouch is printed with traceable identifiers selected from batch codes, QR codes, or date-of-manufacture stamps.

10. The desiccant pouch of claim 1, wherein the pouch exhibits: (a) a moisture absorption of =50% at 25°C and 40% relative humidity, (b) a moisture absorption of =120% at 25°C and 90% relative humidity, and (c) a moisture absorption of =120% at 40°C and 90% relative humidity. wherein the desiccant remains effective and stable for a continuous period of at least 48 days under simulated environmental cycling conditions involving temperature and humidity variations. ABSTRACT A Desiccant The present invention relates to a desiccant composition and its method of manufacture, designed for enhanced moisture absorption and thermal desorption performance in industrial and automotive applications. The invention comprises a blend of magnesium chloride and natural active minerals, optionally with anti-caking agents and other functional additives, formulated in predetermined ratios to provide controlled and efficient moisture regulation under varying environmental conditions. The desiccant is encapsulated in a high-performance, leak-proof, dust-proof, and heat-resistant pouch material, allowing compatibility with harsh automotive environments such as headlamps, ECU housings, battery compartments, and interior lighting systems. Figure 1 , Claims:We Claim:

1. A desiccant comprising: (a) a hygroscopic composition consisting of at least 70% by weight of magnesium chloride and up to 30% by weight of one or more natural active minerals; and (b) a sealed, vapor-permeable pouch enclosing said composition, the pouch comprising a laminated multi-layer structure having an outer layer of polyethylene terephthalate (PET) and an inner layer of Dutech or Dutchess paper; wherein the desiccant pouch exhibits: (i) a moisture absorption capacity of at least 130% of its dry weight at 50°C and 95% relative humidity over 48 days; and (ii) (ii) a moisture retention of at least 96% when exposed to 80°C and 30% relative humidity for 24 hours.

2. The desiccant pouch of claim 1, wherein the natural active minerals comprise one or more selected from bentonite, attapulgite, zeolite, or natural clays.

3. The desiccant pouch of claim 1, wherein the pouch is ultrasonically heat-sealed to prevent leakage of the desiccant material and ensure mechanical integrity under thermal cycling conditions; wherein the pouch is shaped as a flat rectangular sachet or in a customized form adapted to specific automotive components; wherein the desiccant pouch is integrated into a battery pack or sealed electronic module to extend component reliability in high-humidity environments.

4. The desiccant pouch of claim 1, wherein the laminated structure provides water vapor permeability while remaining resistant to tearing and deformation at temperatures up to 85°C.

5. Use of the desiccant pouch as claimed in any one of claims 1 to 4 in an automotive assembly selected from headlamps, electronic control units (ECUs), sensors, battery packs, or cabin interiors, wherein the desiccant provides long-term moisture absorption and controlled thermal desorption; wherein the desiccant pouch is positioned within an automotive lighting unit to prevent internal fogging or condensation.

6. A method of manufacturing a desiccant pouch, the method comprising: (a) mixing magnesium chloride with atleast one or more natural active minerals to form a hygroscopic blend; (b) forming individual sachets of the blend in units ranging from 10 to 20 grams; (c) enclosing the blend in a laminated multi-layer pouch comprising PET and Dutech laminated paper or Dutchess paper; (d) heat-sealing the edges of the pouch ultrasonically; and (e) storing the sealed pouches under vacuum or in airtight packaging to prevent premature moisture absorption.

7. The method of claim 6, wherein the pouch further includes one or more anti-caking agents blended into the composition to enhance flowability during sachet formation.

8. The method of claim 6, wherein the ultrasonic sealing temperature is maintained in the range of 120°C to 160°C to ensure seam integrity under high-temperature automotive conditions.

9. The method of claim 6, wherein the outer PET layer of the pouch is printed with traceable identifiers selected from batch codes, QR codes, or date-of-manufacture stamps.

10. The desiccant pouch of claim 1, wherein the pouch exhibits: (a) a moisture absorption of =50% at 25°C and 40% relative humidity, (b) a moisture absorption of =120% at 25°C and 90% relative humidity, and (c) a moisture absorption of =120% at 40°C and 90% relative humidity. wherein the desiccant remains effective and stable for a continuous period of at least 48 days under simulated environmental cycling conditions involving temperature and humidity variations.

Description:TITLE
Desiccant

FIELD OF THE INVENTION

[001] The invention relates to a high-performance desiccant composition for controlling moisture in enclosed environments. More particularly, the invention relates to a magnesium salt-based automotive desiccant that provides superior moisture absorption capacity, thermal stability, and packaging integrity, specifically designed for use in automotive components such as headlamps, electronic control units (ECUs), sensors, and cabin interiors, where long-term moisture protection is critical to prevent fogging, corrosion, and electrical failure.

BACKGROUND OF THE INVENTION

[002] Over the last two decades, the automotive industry has increasingly moved toward higher integration of sensitive electronics, advanced lighting systems, and smart sensors within vehicle architectures. These components are typically enclosed in sealed housings to protect against contaminants like dust, water, and road debris. However, these enclosures also trap residual moisture from ambient air or manufacturing processes. Once sealed, moisture inside such enclosures can condense due to pressure changes or temperature fluctuations, leading to fogging, corrosion, electrical failure, and degradation of material surfaces.
[003] Traditional desiccants such as silica gel, calcium oxide, molecular sieves, and activated alumina have been widely used to combat moisture ingress. While effective to an extent, these materials face significant performance limitations. Most notably, their moisture absorption capacities are moderate, typically maxing out at 50–60% of their dry weight. In applications where sustained moisture protection is required—especially under high humidity conditions—these conventional desiccants tend to reach saturation quickly, making them unsuitable for long-term automotive use.
[004] A particularly serious concern is the tendency of many conventional desiccants to release previously absorbed moisture when exposed to elevated temperatures. In real-world automotive conditions, enclosures often experience internal temperatures of 70–80°C or more due to engine heat, solar load, or battery operation in electric vehicles. Under such conditions, conventional desiccants may begin to desorb moisture, unintentionally increasing humidity within the component rather than reducing it. This uncontrolled desorption can compromise the reliability and longevity of critical automotive systems.
[005] Equally important is the mechanical and functional design of the desiccant packaging. In many cases, desiccants are packed in sachets or bags made from materials not optimized for automotive-grade environments. These pouches may tear, leak, or fail to allow adequate vapor transfer, especially when subjected to vibration, thermal cycling, or prolonged stress. Further, the absorbent material inside these pouches can clump or cake over time, reducing its active surface area and diminishing the overall moisture-absorbing efficiency.
[006] With the growing adoption of electric vehicles (EVs) and the proliferation of advanced driver-assistance systems (ADAS), moisture management challenges have intensified. Components like battery management systems, inverters, radar and LiDAR units, infotainment modules, and sensor assemblies are packed into compact, thermally stressed environments. These components often operate with little ventilation and undergo frequent on-off cycles, increasing the risk of condensation and long-term moisture accumulation. In such applications, even minor moisture ingress can have catastrophic effects on performance, safety, and component life.
[007] Compounding this problem is the rising demand for environmentally friendly and non-toxic materials in automotive interiors and electronics. Many older desiccant formulations contain substances that can release dust, corrosive leachates, or volatile compounds, making them unsuitable for use in enclosed automotive spaces. Regulatory shifts and consumer expectations have created pressure for cleaner, safer, and more sustainable moisture-control technologies that do not compromise air quality, component integrity, or environmental compliance.
[008] As a result, there is a pressing and unmet need for a next-generation desiccant system tailored for automotive applications. Such a system must be capable of sustaining high levels of moisture absorption over extended periods, even in humid conditions. It must demonstrate exceptional thermal stability with minimal desorption at elevated temperatures. The desiccant should be housed in robust, vapor-permeable, and leak-proof packaging suitable for automotive-grade environments. Importantly, it should be compatible with a wide range of vehicle components, including lighting units, electronic modules, sensors, and cabin interiors, while adhering to environmental safety norms.
[009] In light of these industry challenges, it is imperative to develop a desiccant that addresses all of the above deficiencies through improved material formulation, structural integrity, and application-specific performance.

SUMMARY OF THE INVENTION

[010] In an aspect, the present invention is directed to a high-performance automotive desiccant system comprising a magnesium salt-based absorbent composition enclosed within a multi-layer, laminated, vapor-permeable pouch, designed to offer enhanced moisture absorption, reduced desorption under elevated temperatures, and long-term stability in sealed automotive environments.
[011] In another aspect, the invention provides a desiccant composition comprising at least 70% by weight of magnesium chloride and up to 30% by weight of natural active minerals. The composition may optionally include anti-caking agents to maintain flowability and surface exposure over time. This formulation enables the desiccant to achieve exceptionally high moisture absorption capacities-exceeding 130% of its dry weight under high humidity conditions-while maintaining structural integrity and consistent performance.
[012] In yet another aspect, the invention provides a desiccant bag or sachet wherein the absorbent material is sealed within a composite pouch constructed from an inner layer of breathable, laminated Dutech paper and an outer layer of PET nonwoven fabric. The pouch is heat-sealed ultrasonically to prevent leakage of absorbed moisture or material degradation, and may be fabricated into flat rectangular or custom-fit geometries depending on the target automotive component.
[013] In a further aspect, the invention discloses a method for manufacturing the desiccant bag, comprising the steps of: (i) dry-blending magnesium chloride with a selected active mineral blend; (ii) optionally adding anti-caking agents; (iii) forming individual sachets or pouches containing 10–20 g of the dry mixture; (iv) sealing the desiccant in vapor-permeable composite films via ultrasonic or thermal sealing; and (v) vacuum-packing the final product to avoid pre-activation prior to installation.
[014] In another aspect, the invention relates to the application of the desiccant system in automotive assemblies, particularly in sealed environments such as headlamps, electronic control modules, EV battery packs, sensors, and cabin compartments. The desiccant provides long-lasting humidity control and suppresses condensation, fogging, and corrosion without the risk of moisture desorption or environmental contamination.
[015] In yet another aspect, the desiccant exhibits remarkable stability under high-temperature and high-humidity conditions, retaining over 96% of absorbed moisture even after 24 hours at 80°C and 30% relative humidity. This performance significantly surpasses conventional desiccants like silica gel or calcium oxide, which tend to release moisture under such thermal stress.
[016] In yet another aspect, the invention ensures environmental safety and compliance by using non-toxic, non-volatile, and recyclable materials, making it suitable for sensitive and enclosed automotive spaces where user safety and component integrity are paramount.

BRIEF DESCRIPTION OF THE DRAWINGS
[017] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in the context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 presents a detailed comparison between the present invention and a commercially available desiccant product, highlighting their respective performance in moisture desorption tests under controlled conditions.

DETAILED DESCRIPTION OF THE INVENTION

[018] The terms “comprising”, “comprises” and “comprised of” as used herein are synonymous with “including”, “includes” or “containing”, “contains”, and are inclusive or open-ended and do not exclude additional, non-recited members, elements, or method steps. It will be appreciated that the terms “comprising”, “comprises” and “comprised of” as used herein comprise the terms “consisting of”, “consists” and “consists of”.
[019] Furthermore, the terms “first”, “second”, “third” or “(a)”, “(b)”, “(c)”, “(d)” etc. and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein. In case the terms “first”, “second”, “third” or “(A)”, “(B)” and “(C)” or “(a)”, “(b)”, “(c)”, “(d)”, “i”, “ii” etc. relate to steps of a method or use or assay there is no time or time interval coherence between the steps, that is, the steps may be carried out simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between such steps unless otherwise indicated in the application as set forth herein above or below.
[020] In the following passages, different aspects of the present invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.
[021] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments, as would be understood by those in the art. For example, in the appended claims, any of the claimed embodiments can be used in any combination.
[022] Furthermore, the ranges defined throughout the specification include the end values as well, i.e., a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, the applicant shall be entitled to any equivalents according to applicable law.
[023] In an aspect, the present invention relates to a moisture-absorbing composition that exhibits high efficiency, long-lasting performance, and minimal risk of moisture desorption even under elevated temperatures and fluctuating humidity conditions. It is particularly suitable for use in enclosed or semi-enclosed environments where protection from moisture ingress is essential, especially in temperature-sensitive and corrosion-prone applications such as those found in automotive lighting assemblies, electronic control units (ECUs), cabin interiors, sensors, and other components.
[024] In an embodiment, the invention relates to a hygroscopic composition that comprises a predominant amount of magnesium chloride-constituting at least 70% by weight of the total absorbent mass. Magnesium chloride is known for its high affinity for atmospheric moisture and plays a crucial role in the moisture uptake characteristics of the composition. Alongside the magnesium salt, the formulation includes up to 30% by weight of naturally occurring active minerals. These minerals enhance the absorption kinetics and overall structural performance of the desiccant mass. In some instances, optional additives such as anti-caking agents may also be introduced to maintain the powder flowability and uniformity of dispersion during processing and packaging.
[025] In an embodiment the anti-caking agents are selected from but not limited to compounds such as magnesium oxide, magnesium carbonate, calcium silicate, silicon dioxide, magnesium silicate, talc, and sodium aluminosilicate. These agents are commonly employed in industrial applications to prevent clumping and ensure the free-flowing nature of powdered substances.
[026] For instance, magnesium oxide is renowned for its exceptional moisture absorption capacity and thermal stability, making it effective in preventing caking in various products. Magnesium carbonate serves a similar purpose, offering hygroscopic properties that help maintain the flowability of powders. Calcium silicate and silicon dioxide are also widely used due to their ability to absorb moisture and prevent particle agglomeration. Additionally, magnesium silicate and talc are effective in maintaining the free-flowing characteristics of powdered materials. Sodium aluminosilicate is another agent that helps in preventing caking by absorbing excess moisture
[027] The selection of a specific anti-caking agent depends on factors such as the nature of the product, environmental conditions, and regulatory considerations. These agents are typically used in concentrations ranging from 0.1% to 2% by weight, depending on the specific application and desired efficacy.
[028] In an embodiment, the composition is physically contained within a protective, breathable yet impermeable structure that allows the passage of water vapor without permitting any leakage of the internal material. This is achieved through a composite laminate enclosure formed using an inner layer of Dutech laminated paper and an outer layer comprising nonwoven PET film, which may optionally possess antistatic properties to prevent particle accumulation during handling. These two layers are bonded and sealed ultrasonically along their edges, offering robust containment with resistance to rupture or leakage even under high thermal and mechanical stress. The laminate construction ensures that the desiccant remains effective over extended periods, even in extreme humidity or temperature conditions, while preventing particulate escape or external contamination.
[029] In an embodiment, various geometries and sizes of the enclosure may be employed depending on the application requirements, with the embodiment of a flat rectangular unit being one of the preferred forms due to ease of insertion into compact automotive housings. However, the design is not limited to this shape and may be customized to fit complex contours or confined spaces in electronic or lighting modules.
[030] In an embodiment, the performance characteristics of this composition and its enclosure have been validated under stringent environmental conditions. When exposed to 50°C and 95% relative humidity, the absorbent can retain up to 136% of its own dry weight in moisture. Importantly, even after prolonged exposure to elevated temperatures of 80°C and a relative humidity of 30% for 24 hours, the composition demonstrates minimal desorption, with moisture loss maintained below 2%. These characteristics distinguish the invention significantly from conventional desiccants, such as silica gel and calcium oxide, which often fail to retain absorbed moisture under similar conditions, leading to cyclic release and reabsorption that can compromise sensitive automotive assemblies.
[031] In an embodiment, further tests conducted in environmental chambers over 48 days confirmed the long-term efficacy and stability of the desiccant under typical use scenarios. Automotive validation, including comparative trials as shown in figure 1 has shown that this invention outperforms pre-existing desiccant products in terms of moisture absorption rate, retention, and mechanical integrity of the packaging.
[032] In an embodiment, the desiccant composition of the present invention may be enclosed within a high-performance packaging material selected to balance moisture permeability, mechanical strength, and thermal resistance while preventing leakage and particulate loss. While multi-layered laminated films comprising polyethylene terephthalate (PET), aluminum foil, and low-density polyethylene (LDPE) are commonly employed, alternative materials may also be utilized based on specific end-use conditions and compatibility with the desiccant formulation.
[033] In an alternative embodiment, for instance, nonwoven spunbond fabrics, such as polypropylene or polyester-based nonwovens, may be employed for their high tensile strength, breathability, and thermal stability. These materials allow controlled moisture ingress to activate the desiccant while maintaining structural integrity under mechanical and thermal stress. In automotive applications where permeability needs to be finely tuned, microporous membranes such as expanded polytetrafluoroethylene (ePTFE) or polyolefin-based membranes may be used to allow vapor exchange without compromising dust control or leak resistance.
[034] Where high-temperature exposure is expected, polyimide films or nylon-based multilayers may be used for superior heat resistance and dimensional stability. These materials provide robust protection against thermal deformation and are suitable for integration into enclosures exposed to engine heat, battery housing heat, or prolonged sunlight exposure.
[035] All such packaging materials are preferably selected to be chemically inert with respect to the desiccant composition, non-reactive under operational humidity and temperature conditions, and compliant with applicable industry standards for safety, environmental compatibility, and recyclability.
[036] In another aspect, the invention provides a method for manufacturing a high-efficiency moisture-absorbing unit, suitable for deployment in environments requiring reliable and long-lasting humidity control. The method involves a series of controlled steps to ensure homogeneity, stability, and functionality of the desiccant material, as well as integrity and performance of the final packaged unit.
[037] In an embodiment, the process begins with the preparation of a hygroscopic composition by blending magnesium chloride with one or more active natural minerals. The components are mixed thoroughly to produce a homogeneous formulation, wherein magnesium chloride constitutes at least 70% by weight and the remaining up to 30% comprises selected mineral additives that enhance the kinetics and structural characteristics of the composition. The blending is carried out under controlled ambient conditions to avoid premature exposure to moisture.
[038] In an embodiment, following homogenization, the composition is portioned into discrete units, typically in the range of 10 to 20 grams per sachet. The exact weight may be varied depending on the moisture control requirements of the end-use environment. These portions are then filled into vapor-permeable enclosures fabricated from a multi-layered laminate comprising an inner layer of Dutech paper and an outer nonwoven PET film. The laminate allows ingress of water vapor while preventing leakage or dust release of the absorbent contents. The enclosures are sealed-preferably using ultrasonic sealing techniques-to ensure mechanical integrity and to prevent ingress of ambient humidity during or after the filling process.
[039] In an embodiment, to preserve the hygroscopic efficiency of the composition, the sealed desiccant units are immediately packed in vacuum-sealed or airtight containers. This precaution prevents any premature activation of the desiccant prior to its installation in the intended application environment.
[040] In an embodiment, the method is designed to be compatible with standard manufacturing infrastructure used in the production and packaging of desiccant pouches, allowing for seamless integration into existing production lines. It does not require specialized equipment or exotic materials, thereby making it commercially viable and scalable.
[041] In an embodiment, the resulting product, when manufactured according to this method, exhibits superior moisture absorption performance and exceptional thermal stability. In controlled performance tests, desiccant units manufactured by this process demonstrated absorption capacities exceeding 120% of their dry weight under high humidity conditions (e.g., 90% RH at 25°C and 40°C), and up to 136% under 95% RH at 50°C. Additionally, thermal desorption tests conducted at 80°C and 30% RH over a 24-hour period revealed a desorption loss of less than 4%, affirming the formulation’s capacity to retain moisture under heat stress.
[042] In an embodiment, the method yields a product that is not only functionally robust but also environmentally safe and non-volatile. The manufactured desiccant units have been validated for use in a wide range of automotive systems, including headlamps, cabin lighting modules, battery enclosures in electric vehicles, and control unit housings. Their reliable performance, ease of integration, and long operational lifespan make them a next-generation alternative to traditional silica gel-based or clay-based desiccants.
Examples
[043] An exemplary embodiment of the invention was prepared using a composition consisting of magnesium chloride in a concentration of not less than 70% by weight, combined with natural active minerals constituting not more than 30% by weight. The components were thoroughly mixed to form a homogeneous blend.
[044] The resulting mixture was weighed and portioned into uniform sachets, each having a weight of approximately 15 grams. These portions were then sealed within pre-constructed pouches comprising a multi-layer composite of PET (polyethylene terephthalate) non-woven outer layer and an inner layer of Dutech laminated paper. The pouch edges were ultrasonically sealed to ensure a leak-proof, dust-proof, and moisture-retentive configuration.
[045] Following sealing, the desiccant bags were vacuum packed to avoid any premature activation due to ambient humidity. The samples were stored under these conditions until testing.
[046] Performance testing was conducted under controlled conditions. The desiccant sachets demonstrated a moisture absorption capacity exceeding 120% of their dry weight at 40°C and 90% relative humidity, and greater than 50% absorption at 25°C and 40% RH. Importantly, when subjected to a temperature of 80°C and 30% RH for 24 hours, the bags exhibited less than 2% desorption, confirming their thermal stability and retention performance. Over a 48-day test period in an environmental chamber, the desiccant continued to perform effectively, showcasing its long-term moisture control efficacy.
[047] Referring now to figure 1, a comparative moisture desorption test was conducted to evaluate the thermal retention performance of the present invention against a commercially available desiccant product. The assessment was carried out under two controlled environmental conditions to simulate the thermal stress experienced in real-world automotive applications.
[048] In the first part of the test, both desiccants were subjected to a temperature of 70°C at 15% relative humidity (RH) over a 48-hour period. Moisture desorption levels were recorded at regular intervals from 0 to 48 hours. The desiccant formulated as per the present invention exhibited significantly lower moisture release throughout the testing duration. At the 24-hour mark, it desorbed only 1.89% of its absorbed moisture compared to 6.22% observed for the commercial product. By 48 hours, the desorption from the present invention reached 3.76%, while the commercial product released 11.55% of its moisture content. This demonstrated the superior moisture retention and desorption control of the present formulation under extended thermal stress.
[049] In the second phase of testing, the same samples were exposed to an even more demanding condition of 80°C and 30% RH for 24 hours. The performance trend remained consistent with the earlier test. The desiccant of the present invention continued to demonstrate minimal moisture loss, with desorption values progressing from 0.28% at 1 hour to 7.80% at 24 hours. In contrast, the commercial desiccant displayed a considerably higher rate of desorption, reaching 10.00% at the end of the 24-hour period. This reinforced the efficacy of the present invention in maintaining absorbed moisture under elevated thermal conditions.
[050] Collectively, these results validate the technical advantage of the desiccant composition and packaging design of the present invention. The high magnesium chloride content combined with the laminated, breathable yet leak-proof pouch structure enables not only efficient moisture absorption but also exceptional resistance to thermal desorption. The tests conclusively demonstrate the stability and reliability of the present invention under conditions that replicate harsh automotive environments.
[051] The present invention provides a significant advancement in automotive desiccant technology by leveraging a magnesium salt-based composition with carefully balanced natural minerals. Unlike conventional desiccants such as silica gel, calcium oxide, or molecular sieves, which typically exhibit limited moisture absorption capacity and are prone to moisture desorption at elevated temperatures, the desiccant of the present invention demonstrates remarkable moisture absorption efficiency coupled with superior thermal stability. Specifically, the formulation based on =70% magnesium chloride enables absorption levels exceeding 130% of the desiccant's dry weight, even under high humidity and elevated temperature conditions (50°C, 95% RH). This marks a substantial improvement over the ~30–60% absorption rates of standard desiccants used in automotive applications.
[052] A key advantage of the invention lies in its exceptionally low desorption profile. Where competitor desiccants often release previously absorbed moisture under elevated temperatures - thereby endangering sensitive electronic components - the desiccant disclosed herein retains more than 96% of absorbed moisture at 80°C and 30% RH over a 24-hour period, making it ideal for thermally demanding environments such as engine bays, EV battery housings, and headlamp enclosures. This controlled desorption property enhances the long-term reliability and operational stability of automotive assemblies, particularly in environments subject to thermal cycling.
[053] Another critical benefit of the invention is its innovative packaging solution. The use of a multi-layer laminated pouch, comprising PET nonwoven fabric and Dutech/Dutchess paper, ensures optimal breathability while maintaining mechanical strength and barrier properties. Unlike traditional sachets which may suffer from leakage, dust release, or rupture under heat and pressure, the composite pouch design of this invention is dust-proof, leak-proof, and heat-resistant, with ultrasonic heat sealing providing additional integrity. This enhances both the functional lifespan and safety of the desiccant, especially in sensitive automotive compartments.
[054] Additionally, the invention is designed for versatile integration into a range of automotive components, including but not limited to headlamps, electronic control units (ECUs), interior cabin assemblies, and battery packs. Its ability to be produced in flat or custom geometries and in unit sizes of 10–20 grams allows for seamless incorporation into both legacy systems and next-generation electric vehicles (EVs), thereby supporting modern automotive design requirements.
[055] The invention also offers manufacturing and logistical advantages. Since it uses readily available magnesium chloride and natural minerals, the formulation is cost-effective and scalable. Its robust performance eliminates the need for frequent replacements or dual desiccant strategies, reducing long-term maintenance costs. Furthermore, the product is environmentally benign and non-volatile, contributing to safer handling, storage, and disposal in compliance with automotive industry standards.
[056] Finally, the invention has been independently validated under extended environmental chamber testing, demonstrating reliable performance over 48 days, and has outperformed benchmark products used by established players in the field (e.g., Lumax India). This real-world validation underscores the practical utility and industrial applicability of the invention, positioning it as a superior alternative to existing desiccant technologies in the demanding automotive sector.
[057] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since the modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to the person skilled in the art, the invention should be construed to include everything within the scope of the disclosure.
We Claim:
1. A desiccant comprising:
(a) a hygroscopic composition consisting of at least 70% by weight of magnesium chloride and up to 30% by weight of one or more natural active minerals; and
(b) a sealed, vapor-permeable pouch enclosing said composition, the pouch comprising a laminated multi-layer structure having an outer layer of polyethylene terephthalate (PET) and an inner layer of Dutech or Dutchess paper;
wherein the desiccant pouch exhibits:
(i) a moisture absorption capacity of at least 130% of its dry weight at 50°C and 95% relative humidity over 48 days; and
(ii) (ii) a moisture retention of at least 96% when exposed to 80°C and 30% relative humidity for 24 hours.

2. The desiccant pouch of claim 1, wherein the natural active minerals comprise one or more selected from bentonite, attapulgite, zeolite, or natural clays.

3. The desiccant pouch of claim 1, wherein the pouch is ultrasonically heat-sealed to prevent leakage of the desiccant material and ensure mechanical integrity under thermal cycling conditions; wherein the pouch is shaped as a flat rectangular sachet or in a customized form adapted to specific automotive components; wherein the desiccant pouch is integrated into a battery pack or sealed electronic module to extend component reliability in high-humidity environments.
4. The desiccant pouch of claim 1, wherein the laminated structure provides water vapor permeability while remaining resistant to tearing and deformation at temperatures up to 85°C.
5. Use of the desiccant pouch as claimed in any one of claims 1 to 4 in an automotive assembly selected from headlamps, electronic control units (ECUs), sensors, battery packs, or cabin interiors, wherein the desiccant provides long-term moisture absorption and controlled thermal desorption; wherein the desiccant pouch is positioned within an automotive lighting unit to prevent internal fogging or condensation.
6. A method of manufacturing a desiccant pouch, the method comprising:
(a) mixing magnesium chloride with atleast one or more natural active minerals to form a hygroscopic blend;
(b) forming individual sachets of the blend in units ranging from 10 to 20 grams;
(c) enclosing the blend in a laminated multi-layer pouch comprising PET and Dutech laminated paper or Dutchess paper;
(d) heat-sealing the edges of the pouch ultrasonically; and
(e) storing the sealed pouches under vacuum or in airtight packaging to prevent premature moisture absorption.

7. The method of claim 6, wherein the pouch further includes one or more anti-caking agents blended into the composition to enhance flowability during sachet formation.

8. The method of claim 6, wherein the ultrasonic sealing temperature is maintained in the range of 120°C to 160°C to ensure seam integrity under high-temperature automotive conditions.

9. The method of claim 6, wherein the outer PET layer of the pouch is printed with traceable identifiers selected from batch codes, QR codes, or date-of-manufacture stamps.

10. The desiccant pouch of claim 1, wherein the pouch exhibits:
(a) a moisture absorption of =50% at 25°C and 40% relative humidity,
(b) a moisture absorption of =120% at 25°C and 90% relative humidity, and
(c) a moisture absorption of =120% at 40°C and 90% relative humidity.
wherein the desiccant remains effective and stable for a continuous period of at least 48 days under simulated environmental cycling conditions involving temperature and humidity variations.
ABSTRACT
A Desiccant
The present invention relates to a desiccant composition and its method of manufacture, designed for enhanced moisture absorption and thermal desorption performance in industrial and automotive applications. The invention comprises a blend of magnesium chloride and natural active minerals, optionally with anti-caking agents and other functional additives, formulated in predetermined ratios to provide controlled and efficient moisture regulation under varying environmental conditions. The desiccant is encapsulated in a high-performance, leak-proof, dust-proof, and heat-resistant pouch material, allowing compatibility with harsh automotive environments such as headlamps, ECU housings, battery compartments, and interior lighting systems.

Figure 1
, Claims:We Claim:
1. A desiccant comprising:
(a) a hygroscopic composition consisting of at least 70% by weight of magnesium chloride and up to 30% by weight of one or more natural active minerals; and
(b) a sealed, vapor-permeable pouch enclosing said composition, the pouch comprising a laminated multi-layer structure having an outer layer of polyethylene terephthalate (PET) and an inner layer of Dutech or Dutchess paper;
wherein the desiccant pouch exhibits:
(i) a moisture absorption capacity of at least 130% of its dry weight at 50°C and 95% relative humidity over 48 days; and
(ii) (ii) a moisture retention of at least 96% when exposed to 80°C and 30% relative humidity for 24 hours.

2. The desiccant pouch of claim 1, wherein the natural active minerals comprise one or more selected from bentonite, attapulgite, zeolite, or natural clays.

3. The desiccant pouch of claim 1, wherein the pouch is ultrasonically heat-sealed to prevent leakage of the desiccant material and ensure mechanical integrity under thermal cycling conditions; wherein the pouch is shaped as a flat rectangular sachet or in a customized form adapted to specific automotive components; wherein the desiccant pouch is integrated into a battery pack or sealed electronic module to extend component reliability in high-humidity environments.
4. The desiccant pouch of claim 1, wherein the laminated structure provides water vapor permeability while remaining resistant to tearing and deformation at temperatures up to 85°C.
5. Use of the desiccant pouch as claimed in any one of claims 1 to 4 in an automotive assembly selected from headlamps, electronic control units (ECUs), sensors, battery packs, or cabin interiors, wherein the desiccant provides long-term moisture absorption and controlled thermal desorption; wherein the desiccant pouch is positioned within an automotive lighting unit to prevent internal fogging or condensation.
6. A method of manufacturing a desiccant pouch, the method comprising:
(a) mixing magnesium chloride with atleast one or more natural active minerals to form a hygroscopic blend;
(b) forming individual sachets of the blend in units ranging from 10 to 20 grams;
(c) enclosing the blend in a laminated multi-layer pouch comprising PET and Dutech laminated paper or Dutchess paper;
(d) heat-sealing the edges of the pouch ultrasonically; and
(e) storing the sealed pouches under vacuum or in airtight packaging to prevent premature moisture absorption.

7. The method of claim 6, wherein the pouch further includes one or more anti-caking agents blended into the composition to enhance flowability during sachet formation.

8. The method of claim 6, wherein the ultrasonic sealing temperature is maintained in the range of 120°C to 160°C to ensure seam integrity under high-temperature automotive conditions.

9. The method of claim 6, wherein the outer PET layer of the pouch is printed with traceable identifiers selected from batch codes, QR codes, or date-of-manufacture stamps.

10. The desiccant pouch of claim 1, wherein the pouch exhibits:
(a) a moisture absorption of =50% at 25°C and 40% relative humidity,
(b) a moisture absorption of =120% at 25°C and 90% relative humidity, and
(c) a moisture absorption of =120% at 40°C and 90% relative humidity.
wherein the desiccant remains effective and stable for a continuous period of at least 48 days under simulated environmental cycling conditions involving temperature and humidity variations.