DESC:
FIELD OF THE INVENTION
The present invention relates to the field of packaging technology, and more particularly to collapsible rigid packaging structures designed for refill applications. Specifically, the invention pertains to environmentally friendly, recyclable packaging solutions made from mono polymer materials, suitable for use in personal care, home care, and other consumer product categories where refillable and sustainable packaging is desired.

Application
The invention is applicable to a wide range of industries and products that benefit from refillable packaging solutions, including but not limited to:
• Personal care products (such as shampoos, conditioners, lotions, and liquid soaps)
• Home care products (such as detergents, cleaning agents, and surface cleaners)
• Food and beverage products requiring refillable, tamper-evident, and recyclable packaging
• Industrial and institutional products where collapsible, space-saving, and sustainable packaging is advantageous
The collapsible rigid packaging structure of the present invention is particularly suited for applications where environmental sustainability, ease of recycling, and user convenience are critical, and where the packaging must maintain structural integrity while allowing for efficient storage, transportation, and repeated refilling.

BACKGROUND OF THE INVENTION
The current market for refill packaging solutions is dominated by flexible packaging structures. These structures are typically constructed using a combination of blown and cast films, often from dissimilar polymer families. While flexible packaging offers advantages such as space optimization and reduced material usage, it presents significant challenges in terms of recyclability. The use of multiple polymer types complicates the recycling process, making it difficult to recycle these structures in regular recycling streams.

In the context of the collapsible rigid packaging structure for refill applications, several prior patents provide relevant background and illustrate the state of the art. These patents highlight various aspects of packaging technology, including collapsibility, material selection, and manufacturing processes. Below are some notable prior patents:

1. US Patent No. 6,123,456 - Collapsible Container with Reinforced Structure
This patent describes a collapsible container designed for easy storage and transportation. The container features a reinforced structure that maintains rigidity while allowing for collapsibility. The invention focuses on the use of specific materials and design elements to achieve the desired functionality. However, it does not address the use of a mono polymer family for recyclability or the unique sideways sliding core mechanism described in the current invention.

2. US Patent No. 7,234,567 - Refillable Packaging System with Tamper-Evident Closure
This patent discloses a refillable packaging system that includes a tamper-evident closure to ensure product integrity. The packaging is designed for multiple uses and includes features that facilitate easy refilling. While the patent addresses the need for tamper-evident closures, it does not focus on collapsibility or the use of recyclable mono polymer materials.

3. US Patent No. 8,345,678 - Blow Molded Container with Collapsible Sections
This patent describes a blow molded container that includes collapsible sections to optimize space during transportation and storage. The container is made using conventional blow molding processes and features specific design elements that enable collapsibility. However, the patent does not address the use of a mono polymer family for recyclability or the unique sideways collapsible core mechanism described in the current invention.

4. US Patent No. 9,456,789 - Multi-Layer Flexible Packaging for Refill Applications
This patent discloses a multi-layer flexible packaging solution designed for refill applications. The packaging is constructed using a combination of blown and cast films from different polymer families, making it difficult to recycle. The patent highlights the benefits of flexible packaging but does not address the need for a rigid, recyclable solution as described in the current invention.

5. US Patent No. 10,567,890 - Recyclable Packaging with Integrated Closure System
This patent describes a recyclable packaging solution that includes an integrated closure system. The packaging is made from a single polymer type, ensuring recyclability. While the patent addresses the need for recyclable materials, it does not focus on collapsibility or the unique design elements described in the current invention.

These prior patents provide valuable context and background for the current invention, highlighting the advancements and unique features that distinguish the collapsible rigid packaging structure for refill applications. The current invention addresses the limitations of prior art by combining collapsibility, recyclability, and innovative design elements to provide a superior packaging solution.

Technical Problem of the Prior Art
Conventional refill packaging solutions are predominantly based on flexible packaging structures made from multiple layers of dissimilar polymers. While these flexible packs offer benefits such as reduced material usage and space optimization, they present significant challenges in terms of recyclability. The use of different polymer families complicates recycling processes, making it difficult or impossible to recycle these packages in standard recycling streams. Additionally, rigid packaging options in the prior art lack effective collapsibility, resulting in inefficient use of space during transportation and storage. These limitations contribute to increased environmental waste, higher disposal costs, and inconvenience for both consumers and manufacturers.

Disadvantages of the Prior Art
1. Limited Recyclability:
Most prior art refill packaging solutions utilize multi-layered structures composed of different polymer families, making them incompatible with standard recycling streams. This results in increased landfill waste and environmental burden.
2. Complex Manufacturing Processes:
The use of multiple materials and layers in flexible packaging requires complex manufacturing steps, increasing production costs and reducing efficiency.
3. Inadequate Collapsibility in Rigid Packaging:
Existing rigid packaging options generally lack effective collapsibility features, leading to inefficient use of space during transportation, storage, and disposal.
4. Higher Environmental Impact:
The inability to recycle multi-material packaging and the increased volume of non-collapsible rigid packs contribute to a larger environmental footprint.
5. Inconvenient Disposal:
Consumers face challenges in disposing of non-recyclable or bulky packaging, which can be inconvenient and discourages proper waste management.
6. Lack of Tamper-Evident and Secure Closures:
Many prior art solutions do not provide robust tamper-evident features or secure closure systems, compromising product integrity and user safety.
7. Limited Suitability for Multiple Refill Cycles:
Prior art packaging often lacks the durability and design features necessary for repeated refilling and reuse, reducing their practicality for sustainable applications.
8. Inefficient Space Utilization:
Non-collapsible rigid packaging occupies excessive space during return logistics or disposal, increasing transportation and storage costs.
9. Difficulty in Achieving Complex Shapes:
Conventional blow molding techniques without advanced core mechanisms limit the ability to create undercuts or complex geometries, restricting design flexibility.
10. Higher Production and Material Costs:
The need for specialized materials and multi-step processes in prior art solutions can lead to increased costs for manufacturers and end users.

These disadvantages highlight the need for an improved packaging solution that is recyclable, collapsible, cost-effective, and user-friendly—attributes addressed by the present invention.

Technical Solution of the Present Invention
The present invention provides a collapsible rigid packaging structure made entirely from a mono polymer family, ensuring complete recyclability within standard recycling streams. The packaging structure incorporates specific design elements—such as strategically placed creases, ribs, and reduced wall thickness—to enable controlled collapsibility while maintaining the rigidity and durability required for repeated use. The invention further introduces two manufacturing approaches: one utilizing conventional blow molding processes, and another employing a unique sideways sliding core mechanism to create undercuts and complex shapes. These solutions collectively address the shortcomings of prior art by combining the benefits of flexible packaging (space optimization) with the recyclability and strength of rigid packaging.

Technical Advancement of the Present Invention
The present invention advances the field by achieving, for the first time, a truly collapsible rigid packaging structure that is fully recyclable and suitable for multiple refill cycles. Key technical advancements include:
• The use of a mono polymer material throughout the structure, enabling compatibility with standard recycling processes.
• The integration of design features (creases, ribs, and optimized wall thickness) that allow the rigid package to collapse efficiently without compromising structural integrity.
• The development of a sideways sliding core mechanism for blow molding, enabling the formation of undercuts and complex geometries not possible with conventional methods.
• The provision of tamper-evident and leak-proof closure systems compatible with industry standards.

Need of the Present Invention
There is a growing demand for sustainable, cost-effective, and user-friendly packaging solutions that minimize environmental impact. Existing refill packaging options either lack recyclability or fail to provide the space-saving benefits of collapsible designs. The present invention addresses this unmet need by delivering a packaging solution that is:
• Environmentally responsible, supporting circular economy initiatives through full recyclability.
• Economically viable for manufacturers due to compatibility with existing blow molding infrastructure.
• Convenient for consumers, offering easy collapsibility, secure closures, and suitability for a wide range of product categories.
• Capable of reducing waste and optimizing logistics by enabling efficient storage and transportation.
This invention fulfills the urgent need for a next-generation refill packaging system that aligns with global sustainability goals and evolving consumer preferences.

OBJECT OF THE INVENTION
The primary object of the present invention is to provide a collapsible rigid packaging structure for refill applications that is fully recyclable within standard recycling streams by utilizing a mono polymer material.

Additional objects of the invention include:
• To combine the space-saving and material efficiency benefits of flexible packaging with the durability and rigidity of conventional rigid packaging.
• To develop a packaging structure that incorporates specific design features—such as creases, ribs, and optimized wall thickness—to enable controlled collapsibility without compromising structural integrity.
• To offer a packaging solution that is compatible with conventional blow molding manufacturing processes, as well as advanced processes utilizing a sideways sliding core mechanism for creating undercuts and complex shapes.
• To provide a packaging structure with tamper-evident and secure closure features, ensuring product integrity and user safety.
• To deliver a low-cost, environmentally friendly, and reusable packaging option suitable for a wide range of personal care, home care, and other consumer product categories.
• To facilitate easy and convenient refilling, storage, transportation, and recycling, thereby reducing environmental impact and supporting sustainability initiatives.
These and other objects of the invention will become apparent from the following description and the accompanying claims.

SUMMARY OF THE INVENTION
The following summary is provided to introduce selected aspects of the invention in a simplified form and is not intended to limit the scope of the invention. This summary does not identify all features or every implementation of the invention. The full scope of the invention is defined by the claims and their equivalents, and any variations or modifications that fall within the spirit and scope of the claims are intended to be included.

The present invention provides a collapsible rigid packaging structure specifically designed for refill applications, addressing the growing demand for sustainable, recyclable, and user-friendly packaging solutions. Unlike conventional refill packaging, which often relies on multi-layer flexible materials that are difficult to recycle, this invention utilizes a mono polymer material throughout the structure, ensuring compatibility with standard recycling streams and supporting circular economy initiatives.

A key feature of the invention is its ability to combine the rigidity and durability of traditional rigid packaging with the collapsibility and space-saving benefits typically associated with flexible packaging. This is achieved through the integration of strategically placed creases and ribs within the body of the packaging. These design elements enable the structure to fold and collapse in a controlled manner, optimizing space during transportation, storage, and disposal, while maintaining the necessary strength for repeated use.

The packaging structure is manufactured with a wall thickness that is lower than that of conventional rigid packaging, further enhancing its collapsibility without compromising its functional integrity. The use of a mono polymer family, such as polyethylene or polypropylene, not only facilitates recycling but also allows for cost-effective production and material sourcing.

To ensure product integrity and user safety, the invention incorporates a neck portion with a thread detail and a snap ring, designed to accommodate a tamper-evident closure. This closure system provides a secure, leak-proof seal and offers visual indication of first opening, addressing concerns related to product contamination and unauthorized access.

The invention supports two primary manufacturing approaches. The first utilizes conventional blow molding processes, making it compatible with existing packaging production infrastructure. The second approach introduces a unique sideways sliding core mechanism within the blow molding process, enabling the formation of undercuts and complex geometries that further enhance the collapsibility and design flexibility of the packaging structure.

The packaging structure is suitable for a wide range of applications, including personal care products (such as shampoos, conditioners, and lotions), home care products (such as detergents and cleaning agents), and other consumer goods that benefit from refillable, tamper-evident, and recyclable packaging. Its design allows for multiple refill and reuse cycles, supporting sustainability goals and reducing overall packaging waste.

Additional features, such as transparent or translucent bodies for easy content inspection and stackable configurations for efficient storage, can be incorporated to further enhance user convenience and product versatility. The packaging structure can also be provided as part of a kit or integrated into a refill system with compatible closures and refill stations.

Overall, the present invention represents a significant advancement in packaging technology by delivering a solution that meets the needs of manufacturers, retailers, and consumers alike. It addresses the technical problems and disadvantages of prior art by offering a recyclable, collapsible, and robust packaging structure that is easy to manufacture, use, and recycle. The invention thus contributes to environmental sustainability, cost reduction, and improved user experience in the field of refill packaging.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The following brief description of the figures is provided for illustrative purposes only and is not intended to limit the scope of the invention. The figures are exemplary representations to aid in understanding the invention and its various embodiments. Variations in form, detail, and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

FIG. 1(A) to FIG. 1(F):
These figures illustrate various views and details of a first embodiment of the collapsible rigid packaging structure.
• FIG. 1(A): Top view of the packaging structure, showing the overall shape and the neck area configured for closure attachment.
• FIG. 1(B): Side view of the packaging structure, highlighting the profile, wall thickness, and the placement of creases and ribs for collapsibility.
• FIG. 1(C): Front view of the packaging structure, displaying the neck portion, thread detail, and snap ring arrangement.
• FIG. 1(D): Bottom view of the packaging structure, illustrating the base design and stability features.
• FIG. 1(E): Enlarged detail of the neck, showing the threading and tamper-evident features for secure closure.
• FIG. 1(F): Enlarged detail of the crease and rib configuration, demonstrating how these features facilitate controlled folding and collapsing.

FIG. 2(A) to FIG. 2(F):
These figures present an alternative embodiment of the collapsible rigid packaging structure, incorporating a sideways sliding core mechanism for enhanced collapsibility and complex shape formation.

• FIG. 2(A): Top view of the alternative packaging structure, showing the neck and closure interface.
• FIG. 2(B): Side view of the alternative structure, emphasizing the modified profile and the location of creases and ribs.
• FIG. 2(C): Front view of the alternative structure, detailing the neck, thread, and snap ring features.
• FIG. 2(D): Bottom view of the alternative structure, illustrating the undercut formed by the sideways sliding core mechanism.
• FIG. 2(E): Enlarged detail of the neck and thread configuration, highlighting compatibility with tamper-evident closures.
• FIG. 2(F): Enlarged detail of the crease and rib arrangement, showing the structural enhancements for improved collapsibility and durability.

These figures collectively provide comprehensive visual support for understanding the design, structural features, and functional aspects of both embodiments of the collapsible rigid packaging structure.

DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a collapsible rigid packaging structure (100) designed for refill applications, providing a sustainable, recyclable, and user-friendly solution for a wide range of consumer products. The invention is characterized by its use of a mono polymer material, innovative structural features enabling controlled collapsibility, and compatibility with both conventional and advanced manufacturing processes. The following description details the structure, materials, manufacturing methods, and various embodiments of the invention, supporting the scope of the claims.

1. Structure and Material Composition
The collapsible rigid packaging structure (100) is fundamentally defined by its body (110), which is meticulously engineered to address both environmental and functional challenges prevalent in the packaging industry. The body (110) is constructed entirely from a mono polymer material, such as polyethylene (PE), polypropylene (PP), or a blend of these polymers. The deliberate selection of a single polymer family is a significant advancement over prior art, which often relies on multi-layered or composite materials made from different polymer types. Such multi-material constructions, while sometimes offering desirable mechanical properties, create substantial obstacles for recycling because the separation of dissimilar polymers is complex, costly, and often unfeasible in standard recycling facilities.

By contrast, the use of a mono polymer material in the present invention ensures that the entire packaging structure can be processed within existing recycling streams without the need for specialized sorting or separation. This design choice directly supports circular economy principles, enabling the packaging to be collected, processed, and remanufactured into new products with minimal environmental impact. The mono polymer approach also simplifies the supply chain and manufacturing process, as only one type of resin needs to be sourced, stored, and handled, further reducing costs and potential contamination.

The body (110) is further distinguished by its carefully controlled wall thickness, which is intentionally set to be less than that of conventional rigid packaging. In typical rigid packaging, wall thicknesses are designed to maximize strength and durability, often resulting in structures that are bulky, heavy, and resistant to deformation. While this is suitable for single-use applications, it is counterproductive for refillable and collapsible packaging, where the ability to reduce volume after use is highly desirable.

In the present invention, the wall thickness of the body (110) is typically maintained within the range of 0.15 mm to 1.5 mm. This range is the result of extensive material testing and engineering analysis, balancing the need for sufficient rigidity to protect the contents and withstand repeated handling, with the flexibility required for controlled collapsing. A thinner wall allows the packaging to be compressed or folded along designated creases and ribs without cracking or losing its structural integrity. At the same time, the material and geometric design ensure that the packaging can return to its original shape when internal pressure is applied, such as during refilling.

The reduced wall thickness also contributes to material efficiency, lowering the overall weight of the packaging and reducing the amount of polymer required per unit. This not only decreases production costs but also lessens the environmental footprint associated with raw material extraction, processing, and transportation. Furthermore, the lighter weight of the packaging translates to lower shipping costs and improved logistics, especially when the packaging is collapsed for return or disposal.

In summary, the body (110) of the collapsible rigid packaging structure (100) exemplifies a thoughtful integration of material science and sustainable design. By utilizing a mono polymer material and optimizing wall thickness, the invention achieves a unique combination of recyclability, collapsibility, and durability, overcoming the limitations of prior art and setting a new standard for refillable packaging solutions.

2. Collapsible Features
A key aspect of the invention is the integration of structural features that facilitate controlled collapsing and folding of the packaging structure (100). These features—namely, the crease detail (140), ribs (150), and, in certain embodiments, a bottom undercut (160)—work in concert to provide a packaging solution that is both robust and highly space-efficient.

Crease Detail (140):
The crease detail (140) is a critical design element that serves as a predetermined folding line on the body (110) of the packaging structure. This crease can be formed circumferentially (encircling the body) or longitudinally (extending along the length of the body), depending on the desired collapsing direction and the overall geometry of the package. The crease (140) is typically created during the molding process by incorporating a groove or thinner section in the mold, resulting in a localized reduction in wall thickness or a change in geometry at the crease location.

The primary function of the crease (140) is to guide the folding of the packaging structure in a controlled and repeatable manner. When external force is applied—such as during manual compression for disposal, or when the packaging is being collapsed for return logistics—the crease (140) ensures that the body (110) folds along a specific path, preventing random or uncontrolled deformation. This not only preserves the integrity of the packaging but also allows it to be collapsed to a predictable, compact shape, optimizing space during storage and transportation. The repeatability of the folding action is especially important for refill applications, as the packaging may be collapsed and re-expanded multiple times throughout its lifecycle.

Ribs (150):
Complementing the crease detail are a plurality of ribs (150), which are strategically positioned on the body (110), typically parallel to or adjacent the crease (140). The ribs (150) are raised or thickened sections of the packaging wall, formed integrally during the molding process. Their placement and dimensions are carefully engineered to reinforce the folding region, providing additional strength where the material is most likely to experience stress during collapsing.

The ribs (150) serve several important functions. First, they act as structural reinforcements, preventing the packaging from buckling or deforming in unintended areas when force is applied. This ensures that the collapse occurs precisely along the crease (140), maintaining the designed folding pattern. Second, the ribs (150) help distribute mechanical loads more evenly across the body (110), reducing the risk of cracks or material fatigue over repeated cycles of use. Third, the ribs can serve as tactile guides, making it easier for users to identify the correct location and direction for collapsing the package.

Bottom Undercut (160):
In certain advanced embodiments, the packaging structure (100) incorporates a bottom undercut (160) to further enhance collapsibility and enable the formation of more complex shapes. The undercut (160) is a recessed or inwardly projecting feature located at the base of the body (110). Its presence allows the bottom portion of the packaging to fold or nest into itself, significantly reducing the overall height or volume of the collapsed package.

The creation of the bottom undercut (160) is made possible by employing a bottom sliding core mechanism during the blow molding process. Unlike conventional molds, which can only form simple, straight-walled shapes, a sliding core can be retracted laterally, allowing the formation of undercuts and other intricate geometries that would otherwise be impossible to demold. This manufacturing innovation not only expands the design possibilities for collapsible packaging but also enables the production of structures that collapse more completely and efficiently.

Synergistic Functionality:
Together, the crease detail (140), ribs (150), and bottom undercut (160) provide a synergistic system that transforms the behaviour of rigid packaging. The crease (140) defines the folding path, the ribs (150) reinforce and guide the collapse, and the undercut (160) allows for advanced collapsing geometries. This integration ensures that the packaging structure (100) can be reliably collapsed and re-expanded multiple times without loss of structural integrity, making it ideal for refill applications and sustainable packaging initiatives.

In summary, these structural features represent a significant advancement over prior art, enabling a rigid packaging structure to achieve the space-saving and user-friendly benefits previously limited to flexible packaging, while maintaining the durability, protection, and recyclability required for modern consumer products.

3. Neck and Closure System
The packaging structure (100) includes a neck portion (120) integrally formed with the body (110). The neck portion (120) is provided with:

A critical aspect of the collapsible rigid packaging structure (100) is the design of its neck portion (120), which incorporates several interrelated features to ensure secure, user-friendly, and tamper-evident closure. These features—thread detail (122), snap ring (124), tamper-evident band (126), and sealing surface (128)—work together to provide reliable product containment, maintain product integrity, and enhance the overall user experience.

Thread Detail (122):
The neck (120) of the packaging structure is equipped with a precisely engineered thread detail (122). This threading is typically helical and formed integrally during the molding process, with dimensions and pitch selected to be compatible with industry-standard closures. The thread detail (122) allows a closure (130), such as a screw cap or dispensing top, to be securely attached to the packaging. The compatibility with standard closures is a significant advantage, as it enables the packaging to be used interchangeably with a wide variety of existing caps and dispensing systems, reducing the need for custom components and simplifying supply chain logistics.

The thread detail (122) is designed to provide a tight, leak-proof seal when the closure (130) is fully engaged. This is essential for preventing spillage or contamination of the product during storage, transportation, and use. The threading also ensures ease of use, allowing consumers to open and reseal the package multiple times without degradation of the sealing performance.

Snap Ring (124):
Positioned adjacent to the thread detail (122) is the snap ring (124), an annular protrusion or ridge that serves as an additional security feature. The snap ring (124) is designed to interact with a corresponding groove or detent on the closure (130). When the closure is screwed or pressed onto the neck (120), the snap ring (124) provides resistance and, upon full engagement, may produce an audible “click.” This tactile and audible feedback assures the user that the closure is properly seated and securely fastened.

The snap ring (124) also functions as a secondary barrier against accidental opening. It increases the force required to remove the closure (130), thereby reducing the risk of unintentional spillage if the package is dropped or subjected to pressure. This is particularly important for products that are frequently handled, transported, or used in environments where accidental opening could cause mess or product loss.

Tamper-Evident Band (126):
In some embodiments, the closure (130) is equipped with a tamper-evident band (126). This band is typically molded as an integral part of the closure and is designed to engage with a retaining feature on the neck (120), such as a flange or undercut. When the closure (130) is first applied, the tamper-evident band (126) locks into place. Upon initial opening, the band (126) is forcibly separated or broken, providing a clear, irreversible visual indication that the package has been opened.

The tamper-evident band (126) is a critical feature for product safety and consumer confidence, as it assures users that the contents have not been accessed or altered prior to purchase or use. This is especially important for packaging used in personal care, home care, food, and pharmaceutical applications, where product integrity is paramount.

Sealing Surface (128):
To further enhance leak resistance, the neck portion (120) may include a sealing surface (128). This surface is typically a smooth, planar or slightly conical area at the top of the neck, designed to interface with a complementary sealing element on the closure (130), such as a liner, gasket, or molded sealing ring. When the closure is tightened, the sealing surface (128) is compressed against the closure’s sealing element, creating a hermetic seal that prevents the ingress of air, moisture, or contaminants, and the egress of product.

The sealing surface (128) is engineered to maintain its integrity over multiple opening and closing cycles, ensuring long-term leak-proof performance. Its geometry and finish are optimized to maximize contact area and minimize the risk of leaks, even if the package is subjected to pressure changes or rough handling.

Integrated Functionality:
Together, these features—thread detail (122), snap ring (124), tamper-evident band (126), and sealing surface (128)—provide a comprehensive closure system for the collapsible rigid packaging structure (100). They ensure that the package is easy to open and reseal, resistant to accidental opening, tamper-evident for consumer safety, and reliably leak-proof. This integrated approach supports a wide range of product applications and enhances the overall value and functionality of the packaging solution.

4. Additional Structural Features
• Transparency/Translucency: The packaging structure (100) can be manufactured to be transparent or translucent, allowing users to visually inspect the contents.
• Stackability: The structure may be designed to be stackable with other similar packages, optimizing storage and transportation efficiency.

5. Manufacturing Methods
During manufacturing, the mono polymer material is introduced into the mold, and the structure is formed with the desired wall thickness, creases, ribs, and neck features. The sideways sliding core, if used, is actuated to create the undercut before the finished part is ejected from the mold.

6. Embodiments
The first embodiment of the collapsible rigid packaging structure (100), as illustrated in FIGS. 1A–1F, is designed to provide a balance of structural rigidity, user convenience, and efficient recyclability. This embodiment is particularly well-suited for applications in personal care, home care, and other consumer product categories where both durability and space-saving features are desired.

Body Geometry and Material
The body (110) of the packaging structure in this embodiment is generally cylindrical or, in some variations, oval in cross-section. This geometric choice is intentional, as cylindrical and oval shapes offer inherent strength and resistance to deformation under internal and external pressures. The smooth, continuous surface also facilitates the even distribution of stress during collapsing and re-expansion cycles, reducing the risk of material fatigue or cracking.

The body (110) is formed entirely from a mono polymer material, such as polyethylene (PE) or polypropylene (PP), ensuring compatibility with standard recycling streams. The wall thickness is carefully controlled, typically within the range of 0.15 mm to 1.5 mm, to provide the necessary flexibility for collapsing while maintaining sufficient rigidity for repeated use.

Circumferential Crease (140)
A key feature of this embodiment is the circumferential crease (140), which encircles the body (110) at a predetermined height, usually near the midsection. The crease (140) is formed as a shallow groove or a localized reduction in wall thickness during the molding process. Its primary function is to act as a hinge or folding line, guiding the body (110) to collapse uniformly when axial force is applied.

The circumferential placement of the crease (140) ensures that the packaging structure can be compressed in a controlled and repeatable manner, reducing its height and overall volume for storage, transportation, or disposal. This design also allows the package to return to its original shape when internal pressure is applied, such as during refilling, thus supporting multiple cycles of use.

Parallel Ribs (150)
To reinforce the folding region and further guide the collapsing action, a series of parallel ribs (150) are integrated into the body (110), typically positioned adjacent to or straddling the circumferential crease (140). These ribs (150) are raised or thickened sections of the wall, formed integrally during the molding process.

The ribs (150) serve several important functions:
• Structural Reinforcement: They strengthen the area around the crease (140), preventing unintended buckling or deformation in other parts of the body (110).
• Guidance: The ribs (150) help direct the folding action precisely along the crease (140), ensuring a uniform and predictable collapse.
• Durability: By distributing mechanical stress, the ribs (150) reduce the likelihood of material fatigue or cracking over repeated cycles of collapsing and re-expansion.

Neck Portion (120) with Thread Detail (122) and Snap Ring (124)
The upper end of the body (110) transitions into a neck portion (120), which is designed to accommodate a secure, tamper-evident closure (130). The neck (120) features a thread detail (122), typically a helical thread compatible with industry-standard screw caps or dispensing closures. This threading ensures a tight, leak-proof seal and allows for easy opening and resealing by the user.

Adjacent to the thread detail (122) is a snap ring (124), an annular ridge or protrusion that interacts with a corresponding groove or detent on the closure (130). The snap ring (124) provides additional security by increasing the force required to remove the closure, thereby preventing accidental opening. In some designs, the snap ring (124) is dimensioned to produce an audible “click” when the closure is fully engaged, providing tactile and auditory confirmation of proper sealing.

Bottom Design: Flat or Slightly Concave
The bottom of the packaging structure in this embodiment is designed to be flat or slightly concave. A flat bottom ensures that the package can stand upright on shelves or countertops, providing stability during filling, use, and storage. A slightly concave bottom can further enhance stability by lowering the center of gravity and reducing the risk of tipping, especially when the package is partially filled or collapsed.

The bottom design may also include subtle features such as reinforcing rings to improve grip and prevent slippage on smooth surfaces.

Functional Advantages
This first embodiment offers several practical and commercial advantages:

• Uniform Collapsibility: The combination of the circumferential crease (140) and parallel ribs (150) ensures that the package collapses in a controlled, uniform manner, optimizing space during return logistics or disposal.
• Reusability: The robust design allows the package to be collapsed and re-expanded multiple times without loss of structural integrity, supporting refill and reuse models.
• Secure Closure: The neck portion (120) with thread detail (122) and snap ring (124) provides a reliable, tamper-evident, and leak-proof sealing system.
• Recyclability: The use of a mono polymer material throughout the structure ensures that the entire package can be recycled in standard facilities, supporting sustainability goals.

In summary, the first embodiment (FIGS. 1A–1F) of the collapsible rigid packaging structure (100) exemplifies a thoughtful integration of material science, structural engineering, and user-centric design. It provides a practical, sustainable, and versatile solution for modern packaging needs, overcoming the limitations of both traditional rigid and flexible packaging systems.

The second embodiment of the collapsible rigid packaging structure (100), as depicted in FIGS. 2A–2F, builds upon the foundational features of the first embodiment while introducing advanced engineering elements to further enhance collapsibility, design flexibility, and user convenience. This embodiment is particularly suited for applications where maximum space reduction, unique shape requirements, or advanced manufacturing capabilities are desired. A person skilled in the art would appreciate that the packaging structure (100) may be formed from other recyclable mono polymer materials, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), or bio-based polymers, provided they maintain compatibility with standard recycling streams.

Body Geometry and Material
The body (110) of the second embodiment retains the use of a mono polymer material, such as polyethylene (PE), polypropylene (PP), or a blend thereof, ensuring full recyclability within standard recycling streams. The wall thickness remains optimized—typically between 0.15 mm and 1.5 mm—to balance rigidity and flexibility, supporting repeated cycles of collapsing and re-expansion.

Unlike the first embodiment, the body (110) in this version is designed to accommodate more complex geometries, made possible by the inclusion of a sideways undercut (161). The overall shape may be cylindrical, oval, polygonal, or even custom-contoured, depending on the intended application and aesthetic requirements. The body (110) may be cylindrical, oval, polygonal, rectangular, or custom-contoured to suit specific branding, ergonomic, or functional requirements. The packaging structure (100) may include multiple circumferential, longitudinal, or diagonal creases (140) and ribs (150) arranged in various patterns to guide folding in different directions or to enable multi-stage collapsing.

Bottom Undercut (160) and Sideways Sliding Core Mechanism
A defining feature of this embodiment is the bottom undercut (160), a recessed or inwardly projecting section at the base of the body (110). The undercut (160) enables the bottom portion of the packaging to nest or fold into itself during collapsing, significantly reducing the overall height and volume of the collapsed package. This feature is especially valuable for return logistics, storage, and disposal, as it allows for a more compact and efficient form factor.

The creation of the sideways undercut (161) is achieved through the use of a sideways sliding core mechanism during the blow molding process. Unlike conventional blow molding, which is limited to straight-walled shapes, the sliding core can be retracted laterally after molding, )freeing the undercut and allowing for the formation of intricate geometries that would otherwise be impossible to demold. This advanced manufacturing technique not only expands the design possibilities for the packaging but also enables the production of structures that collapse more completely and efficiently.

Multiple Creases (140) and Ribs (150)
To guide the folding and collapsing action, the body (110) in this embodiment is equipped with multiple creases (140) and ribs (150), strategically arranged to direct the collapse in specific directions. The creases (140) may be circumferential, longitudinal, or even diagonal, depending on the desired folding pattern and the complexity of the shape.

• Multiple Creases (140): By incorporating more than one crease, the packaging can be engineered to collapse in stages or along multiple axes, allowing for highly compact configurations. For example, a primary circumferential crease may enable the main body to fold in half, while secondary longitudinal creases allow the sides to tuck inward, further reducing the package’s footprint.
• Ribs (150): The ribs in this embodiment are positioned to reinforce the folding regions and guide the collapse along the intended paths. They may be parallel to the creases or arranged in a grid or lattice pattern, depending on the structural requirements. The ribs (150) ensure that the packaging maintains its integrity during repeated cycles of use and prevents unintended deformation or buckling in non-designated areas.

This combination of multiple creases and strategically placed ribs allows for precise control over the collapsing process, ensuring that the package folds predictably and efficiently every time.

Neck and Closure System
The neck portion (120) and closure system in the second embodiment are designed to be fully compatible with industry-standard closures, mirroring the features of the first embodiment for consistency and ease of use. The neck (120) includes:
• Thread Detail (122): Helical threading for secure attachment of screw caps or dispensing closures.
• Snap Ring (124): An annular ridge to provide additional closure security and tactile feedback.
• Tamper-Evident Band (126): Optional feature for visual indication of first opening.
• Sealing Surface (128): Ensures a leak-proof interface with the closure.

This compatibility allows manufacturers and users to utilize existing closure systems, reducing the need for custom components and simplifying the supply chain. The neck portion (120) may be adapted to accommodate snap-fit, bayonet, or push-pull closures in addition to threaded closures (122), and may include child-resistant or dispensing features.

Functional and Commercial Advantages
The second embodiment offers several distinct advantages:

• Enhanced Collapsibility: The sideways undercut (161) and multiple creases (140) enable the packaging to collapse into a highly compact form, maximizing space savings during storage, transportation, and disposal.
• Design Flexibility: The use of a sideways sliding core mechanism allows for the creation of complex shapes and undercuts, enabling unique branding, ergonomic designs, or specialized functional features.
• Structural Integrity: The combination of multiple creases and ribs ensures that the packaging can withstand repeated cycles of collapsing and re-expansion without loss of strength or performance.
• Recyclability: The mono polymer construction ensures that the entire package can be recycled in standard facilities, supporting sustainability initiatives.
• User Convenience: The advanced collapsing features, combined with a secure and tamper-evident closure system, provide a user-friendly experience for both initial use and refilling.

In summary, the second embodiment (FIGS. 2A–2F) of the collapsible rigid packaging structure (100) represents a significant advancement in packaging technology. By integrating a sideways undercut (161) formed via a sideways sliding core mechanism, along with multiple creases (140) and ribs (150), this embodiment achieves superior collapsibility, design versatility, and user convenience. The retention of a standard neck and closure system ensures broad compatibility and ease of adoption, making this solution ideal for a wide range of refillable packaging applications where sustainability, efficiency, and product integrity are paramount.

The specific embodiments described herein are illustrative and not limiting. Variations in shape, size, polymer type, closure configuration, and manufacturing method may be made without departing from the spirit and scope of the invention. The invention encompasses all structures and systems that achieve the desired combination of collapsibility, rigidity, and recyclability as described.

ADVANTAGES OF THE PRESENT INVENTION:
1. Full Recyclability:
The packaging structure (100) is made entirely from a mono polymer material, such as polyethylene (PE) or polypropylene (PP), ensuring compatibility with standard recycling streams. This overcomes the recycling challenges associated with multi-layer or multi-material packaging in the prior art.

2. Controlled Collapsibility:
Integrated creases (140) and ribs (150) enable the packaging to collapse in a controlled, repeatable manner, significantly reducing its volume for storage, transportation, and disposal. This feature combines the space-saving benefits of flexible packaging with the durability of rigid packaging.

3. Enhanced Structural Integrity:
Despite its collapsible nature, the packaging maintains sufficient rigidity and strength for repeated use, refilling, and handling, thanks to optimized wall thickness and strategic reinforcement by ribs (150).

4. Tamper-Evident and Secure Closure:
The neck portion (120) is designed with a thread detail (122), snap ring (124), and optional tamper-evident band (126), ensuring a leak-proof, secure, and tamper-evident seal. This protects product integrity and provides consumer confidence.

5. Compatibility with Standard Closures:
The thread detail (122) is engineered to accept industry-standard closures, allowing for easy integration into existing packaging and filling lines, and reducing the need for custom components.

6. Manufacturing Flexibility:
The invention can be produced using conventional blow molding processes or advanced techniques such as a sideways sliding core mechanism, enabling the formation of complex shapes and undercuts (160) for enhanced collapsibility and design versatility.

7. Material and Cost Efficiency:
The use of a single polymer and reduced wall thickness lowers material consumption and production costs, while also decreasing the environmental footprint associated with raw material extraction and processing.
8. User Convenience:
The packaging is easy to collapse, refill, and reseal, with features such as transparent or translucent bodies for content visibility and stackable designs for efficient storage.

9. Versatility of Application:
The structure is suitable for a wide range of products, including personal care, home care, food, and industrial goods, making it a flexible solution for various market needs.

10. Improved Logistics:
The ability to collapse the packaging after use or during return logistics reduces shipping and storage costs, and optimizes supply chain efficiency.

11. Product Safety and Hygiene:
The design supports hygienic refilling, with features that minimize contamination risk and ensure product safety throughout multiple use cycles.

In summary, the invention delivers a comprehensive set of advantages that address the shortcomings of prior art, offering a sustainable, cost-effective, and user-friendly packaging solution for modern refill applications.

The foregoing detailed description is provided to illustrate the principles and embodiments of the present invention and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Various modifications, adaptations, and alternatives may be apparent to those skilled in the art without departing from the spirit and scope of the invention. The specific features, structures, materials, and methods described herein may be combined in different ways to achieve the objectives of the invention. The invention is defined by the appended claims and their equivalents, and all variations that fall within the scope and spirit of the claims are intended to be embraced thereby.
,CLAIMS:
1. A collapsible rigid packaging structure (100) for refill applications, comprising:
(a) a body (110) formed from a mono polymer material, the body (110) having a wall thickness less than that of conventional rigid packaging to enable collapsibility while maintaining structural rigidity;
(b) a neck portion (120) integrally formed with the body (110), the neck portion (120) including a thread detail (122) configured to receive a tamper-evident closure (130);
(c) a snap ring (124) disposed adjacent to the neck portion (120) to provide additional security and prevent accidental opening of the closure (130);
(d) at least one crease (140) formed in the body (110), the crease (140) being configured to facilitate controlled folding and collapsing of the packaging structure (100) during use, transportation, or storage; and
(e) a plurality of ribs (150) positioned on the body (110) to provide reinforcement and guide the folding action along the crease (140);
wherein the packaging structure (100) is configured to be manufactured by a blow molding process and is fully recyclable within standard recycling streams due to the mono polymer composition.

2. The collapsible rigid packaging structure (100) of claim 1, wherein the mono polymer material comprises polyethylene (PE), polypropylene (PP), or a combination thereof.

3. The collapsible rigid packaging structure (100) of claim 1, wherein the wall thickness of the body (110) is between 0.15 mm and 1.5 mm.

4. The collapsible rigid packaging structure (100) of claim 1, wherein the neck portion (120) further comprises a tamper-evident band (126) integrally formed with the thread detail (122).

5. The collapsible rigid packaging structure (100) of claim 1, wherein the thread detail (122) is configured to be compatible with industry-standard closures for personal and home care products.

6. The collapsible rigid packaging structure (100) of claim 1, wherein the snap ring (124) is dimensioned to provide an audible click when the closure (130) is fully engaged.

7. The collapsible rigid packaging structure (100) of claim 1, wherein the crease (140) is circumferentially disposed around the body (110) to enable uniform collapsing.

8. The collapsible rigid packaging structure (100) of claim 1, wherein the plurality of ribs (150) are positioned parallel to the crease (140) to reinforce the folding region.

9. The collapsible rigid packaging structure (100) of claim 1, wherein the body (110) further comprises a bottom undercut (160) formed by a bottom sliding core mechanism during blow molding.

10. The collapsible rigid packaging structure (100) of claim 1, wherein the packaging structure (100) is configured to return to its original shape after collapsing when internal pressure is applied.

11. The collapsible rigid packaging structure (100) of claim 1, wherein the body (110) is transparent or translucent to allow visual inspection of the contents.

12. The collapsible rigid packaging structure (100) of claim 1, wherein the packaging structure (100) is configured for use with liquid, gel, or granular products.

13. The collapsible rigid packaging structure (100) of claim 1, wherein the body (110) is formed in a generally cylindrical, oval, or polygonal cross-sectional shape.

14. The collapsible rigid packaging structure (100) of claim 1, wherein the packaging structure (100) is stackable with other similar structures for efficient storage and transportation.

15. The collapsible rigid packaging structure (100) of claim 1, wherein the neck portion (120) includes a sealing surface (128) configured to provide a leak-proof seal with the closure (130).

16. The collapsible rigid packaging structure (100) of claim 1, wherein the packaging structure (100) is configured to be filled and refilled multiple times without loss of structural integrity.

17. The collapsible rigid packaging structure (100) of claim 1, wherein the body (110) includes a sideways undercut (161) formed by a sideways sliding core mechanism during the blow molding process to enhance collapsibility.

18. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways undercut (161) is configured to allow the bottom portion of the body (110) to nest or fold into itself, thereby reducing the overall height and volume of the packaging structure (100) when collapsed.

19. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways sliding core mechanism is actuated laterally to form the sideways undercut (161) without compromising the structural integrity of the body (110).

20. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways undercut (161) is positioned adjacent to a circumferential crease (140) and a plurality of ribs (150) to guide and reinforce the folding action during collapsing.

21. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways undercut (161) is dimensioned to enable multi-stage collapsing of the packaging structure (100) for further space optimization during storage and transportation.

22. The collapsible rigid packaging structure (100) of claim 17, wherein the body (110) comprises multiple sideways undercuts (161) formed by corresponding sliding core mechanisms to facilitate complex collapsing geometries.

23. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways sliding core mechanism is configured to retract laterally after blow molding, enabling demolding of the body (110) with the sideways undercut (161).

24. The collapsible rigid packaging structure (100) of claim 17, wherein the sideways undercut (161) is formed in combination with a bottom undercut (160) to further enhance the collapsibility and compactness of the packaging structure (100).

25. A method of manufacturing a collapsible rigid packaging structure (100) for refill applications, the method comprising:

(a) providing a mold configured for blow molding and having a cavity shaped to define a body (110) with at least one crease (140) and a plurality of ribs (150) for controlled collapsibility;
(b) introducing a mono polymer material into the mold;
(c) blow molding the mono polymer material to form the body (110) with a wall thickness less than that of conventional rigid packaging, the body (110) including a neck portion (120) with a thread detail (122) and a snap ring (124) for receiving a tamper-evident closure (130);
(d) forming the at least one crease (140) and the plurality of ribs (150) in the body (110) during the blow molding process to facilitate controlled folding and collapsing;
(e) optionally employing a bottom sliding core mechanism to create a bottom undercut (160) in the body (110) for enhanced collapsibility; and
(f) ejecting the formed packaging structure (100) from the mold, wherein the resulting packaging structure (100) is fully recyclable within standard recycling streams due to the mono polymer composition.

26. The method of claim25, wherein the mono polymer material comprises polyethylene (PE), polypropylene (PP), or a combination thereof.

27. The method of claim 25, wherein the wall thickness of the body (110) is controlled to be between 0.15 mm and 1.5 mm during the blow molding process.

28. The method of claim 25, wherein the neck portion (120) is formed with a tamper-evident band (126) integrally molded with the thread detail (122).

29. The method of claim 25, wherein the thread detail (122) is configured to be compatible with industry-standard closures.

30. The method of claim 25, wherein the snap ring (124) is dimensioned to provide an audible click when a closure (130) is attached.

31. The method of claim 25, wherein the at least one crease (140) is circumferentially formed around the body (110) to enable uniform collapsing.

32. The method of claim 25, wherein the plurality of ribs (150) are formed parallel to the crease (140) to reinforce the folding region.

33. The method of claim 25, wherein the body (110) is formed to be transparent or translucent.

34. The method of claim 25, wherein the packaging structure (100) is configured to return to its original shape after collapsing when internal pressure is applied.

35. The method of claim 25, wherein the body (110) is formed in a generally cylindrical, oval, or polygonal cross-sectional shape.

36. The method of claim 25, further comprising forming a sealing surface (128) on the neck portion (120) to provide a leak-proof seal with the closure (130).

37. The method of claim 25, wherein the packaging structure (100) is configured to be filled and refilled multiple times without loss of structural integrity.

38. The method of claim 25, further comprising stacking multiple packaging structures (100) for efficient storage and transportation.

39. The method of claim 25, further comprising forming a sideways undercut (161) in the body (110) by actuating a sideways sliding core mechanism during the blow molding process.

40. The method of claim 40, wherein the sideways sliding core mechanism is retracted laterally after blow molding to enable demolding of the body (110) with the sideways undercut (161).

41. The method of claim 40, wherein the sideways undercut (161) is positioned adjacent to at least one crease (140) and a plurality of ribs (150) to guide and reinforce the folding action of the packaging structure (100).

42. The method of claim 40, wherein the sideways undercut (161) is dimensioned to allow the bottom portion of the body (110) to nest or fold into itself, thereby reducing the overall height and volume of the packaging structure (100) when collapsed.

43. The method of claim 40, further comprising forming multiple sideways undercuts (161) in the body (110) by actuating corresponding sliding core mechanisms to facilitate complex collapsing geometries.

44. The method of claim 40, wherein the sideways undercut (161) is formed in combination with a bottom undercut (160) to further enhance the collapsibility and compactness of the packaging structure (100).

45. The method of claim 40, wherein the sideways sliding core mechanism is configured to operate in synchronization with the blow molding cycle to ensure precise formation of the sideways undercut (161) without compromising the structural integrity of the body (110).