Bottle Cap with Integrated Water-Soluble Flavor Chamber

Patent & Production

At a glance

What the claims cover, in plain language

Claim 1 - A bottle cap comprising a top plate with a first opening, an annular side wall, and a bottom plate with a second opening. These form an accommodating space containing water-soluble edible flavor components. First and second blocking structures are placed on the top and bottom plates respectively to keep the solid flavor components inside while allowing liquid to flow through the space.

Claim 2-4 - Adds a flow guide structure within the accommodating space to change the liquid path, potentially connecting the top and bottom plates to form a specific fluid channel.

Claim 5 - Specifies that the bottom plate and second blocking structure can be integrally formed and the bottom plate is detachably disposed inside the ring-shaped sidewall.

Claim 6-8 - Details the flavor components as granules or capsules containing solid or non-solid flavoring agents.

Claim 9 - Covers the entire bottled beverage system using the cap described above.

Claims 10-20 - Describe alternative embodiments, including a liquid storage member with auxiliary walls and communication channels, and variations on the lifting cover and snap-fit mechanisms.

This is a simplified reading for orientation only. The legal scope is defined by the exact claim wording in the official Chinese document.

What this means for US production

This patent was filed in China and has been withdrawn (abandoned) since August 2025. The public record shows no US or other foreign counterpart.

Two points to settle early:

• Other patents may exist. The field of “mix-in-the-cap” beverage closures is competitive. While this specific structural arrangement is no longer protected in China, other companies hold active patents on similar dual-chamber caps or valve-based mixing systems in the US. A freedom-to-operate (FTO) review is recommended to check for existing US patents on integrated flavor chambers before tooling.
• Material Compliance. Since the cap contacts food/beverages, the resin choice must meet FDA standards. The withdrawal of the patent does not exempt the product from regulatory safety requirements.

Customization and manufacturing

What can be customized

Things to plan for (US market)

• FDA 21 CFR - Food Contact Substances. All resins used in the cap must be approved for food contact.
• Proposition 65 (California) - Screening for chemicals known to cause cancer or reproductive harm in plastics and adhesives.
• Child Safety - If marketed near children, consider ASTM F963 toy safety standards if the cap is considered a play item, though primarily it is a package.
• Recycling Codes - Ensure the resin type matches local recycling capabilities (usually PP #5 or HDPE #2).

How a project runs

1. Inquiry - Define bottle compatibility, flavor volume, and target cost.
2. Design - CAD modeling of the two-plate chamber and blocking structures.
3. Prototype - 3D printed samples for fit testing; CNC machined aluminum for initial molding trials.
4. Pilot Run - Injection molding test shots; leak and flow rate verification.
5. Production - Multi-cavity injection molding, assembly, and quality control.

Quantities & timeline

The design requires precision molds for the top and bottom plates, which are likely separate cavities or a multi-shot mold depending on complexity. Flow rates depend heavily on the tolerance of the blocking structures. Send us your bottle neck specs, desired flavor volume, and estimated annual quantity and we will reply with options.

Production notes

Tooling and process

Injection molding is likely the main process for the cap body, top lid, and bottom plate. Multi-cavity steel molds are typically needed for the chamber plates and blocking structures. The perforated or mesh blocking insert may be a separate molded part or an inserted screen. Assembly usually relies on snap-fit or ultrasonic welding to secure the bottom plate, with a silicone or TPE gasket press-fit where a seal is required.

Cost drivers

Tooling cost depends mainly on the number of cavities and the complexity of the two chamber plates. Material grade matters because the resin must be food-contact approved. Add-on costs typically come from decoration such as in-mold labeling and from leak testing.

Prototyping path

Prototypes would likely start with 3D-printed cap bodies for fit and flow checks, followed by machined or silicone-cast inserts for the blocking structure. Functional samples should be tested on the target bottle neck finish. Flow rate and leak behavior typically need several iterations before tooling.

What we would change before tooling

We would likely tune the opening sizes and mesh density against the intended granule size. Wall thickness around the threads and the bottom plate joint should be reviewed for moldability. The seal area may need a small redesign depending on the bottle finish selected.

Common failure points

Leaks at the bottom plate joint are a typical risk if the weld or snap-fit is inconsistent. Granules may bridge at the openings if the mesh is too fine for the flavor particle size. Thread engagement and cap torque can vary with resin shrinkage, so dimensions typically need confirmation on pilot shots.

Patent drawings

Drawings reproduced from the public patent document for reference.

Frequently asked questions

How does the flavor get into the drink?

The cap has a hidden chamber between its top and bottom plates. You put water-soluble granules in there. When you tilt or shake the bottle, liquid from the bottle enters the chamber through the bottom opening, dissolves the granules, and then exits through the top opening as a flavored drink.

Do I need to press a button or pull a tab?

No. The design relies on gravity and movement. As long as the bottle is upright enough for liquid to reach the bottom opening, and tilted enough for the mixed liquid to reach the top opening, it works automatically. Some versions might include a lifting cover for hygiene, but the core mixing is passive.

Can it handle hot liquids?

It depends on the plastic used. Standard polypropylene (PP) handles up to about 100°C (212°F), suitable for warm water or tea. For boiling water, you would need a higher temperature-resistant resin like Tritan or special-grade PP, confirmed in design.

What types of flavors can be used?

Any water-soluble ingredient: coffee granules, sugar, salt, electrolyte powders, or even freeze-dried fruit bits if they dissolve quickly. The patent mentions granules and capsules. Non-soluble items like large fruit chunks would clog the blocking structures.

Is it difficult to clean?

These caps are typically designed for single-use or disposable applications to maintain hygiene. If reusable, the bottom plate can sometimes be detached for cleaning, but this adds complexity to the sealing mechanism. Most commercial implementations treat it as a consumable part.

Will it leak if I drop the bottle?

The blocking structures are designed to keep solids in, but liquid can move. If the bottle is shaken violently, liquid might splash into the chamber prematurely. However, the tight tolerances of the injection-molded parts usually prevent significant leaking unless the cap is loose on the bottle threads. Drop tests are required to confirm seal integrity.

Can this design be made and sold in the US?

The patent was filed in China and has been withdrawn (abandoned) as of August 2025. The public record shows no US counterpart, so this specific patent does not restrict the design in the US. However, other active US patents may cover similar mixing technologies, so a freedom-to-operate check is advised.

Are you affiliated with the patent owner?

No. IP2M is an independent design and manufacturing service working from the public patent document.

Request a quote

Click Request a Quote below to see our email address - copy it, or open your email app with a ready-made message. Please mention patent CN216612061U in the subject.

Helpful details to include:

• Your company and channel (beverage brand, supplement maker, outdoor gear retailer)
• Bottle neck finish (PCO 1810, 1881, or custom dimensions)
• Flavor volume needed in the chamber (grams or milliliters)
• Target retail price per unit
• Estimated quantity (initial order and annual projection)
• Timeline - when you would like prototypes and mass production

You can also reach us at (332) 203-9997.