How Earl Tupper Invented the Airtight Plastic Food Container
A 1947 patent for a flexible plastic container with a unique, airtight lid that seals by pressing down on the center, creating the foundation for Tupperware.
Original patent title: “Open mouth container and nonsnap type of closure therefor”
A 1947 patent for a flexible plastic container with a unique, airtight lid that seals by pressing down on the center, creating the foundation for Tupperware. Granted to Individual in 1949 with 116 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
The patent describes a container made of flexible plastic with a groove around the rim. The lid is designed with a matching ridge. When the user presses the center of the lid, it forces the air out and creates a vacuum-like seal against the container wall. This mechanism allows for a secure closure without needing complex mechanical latches or snaps.
The gap
What does this patent NOT cover?
- Does not cover rigid glass or metal containers that cannot flex to form a seal.
- Does not cover lids that require mechanical hinges or external clamps to stay closed.
- Does not cover containers made of non-polyethylene materials that lack the necessary flexibility.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The genius was using the material's own flexibility to create a seal, rather than relying on a separate gasket or mechanical locking mechanism.
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Original Tupperware containers
Modern flexible plastic food storage bowls
Generic airtight plastic kitchen canisters
Why it matters
The bigger picture
This invention launched the food storage industry as we know it. By enabling an airtight seal in a lightweight, durable plastic, it changed how families stored leftovers and led to the iconic Tupperware party business model.
Filed
June 2, 1947
Granted
November 8, 1949
Market context
Who's building on this
Companies in this space
Tupperware Brands Corporation continues to iterate on this original design. Many consumer goods companies, such as Rubbermaid and OXO, have developed variations of this flexible-seal technology for modern kitchen storage.
Market impact
This patent enabled the creation of the home food storage market. It replaced heavy, breakable glass and metal containers with lightweight, stackable plastic, fundamentally altering kitchen organization and food preservation habits globally.
Claim 1 — Plain English
What this patent covers
The patent describes a container made of flexible plastic with a groove around the rim. The lid is designed with a matching ridge. When the user presses the center of the lid, it forces the air out and creates a vacuum-like seal against the container wall. This mechanism allows for a secure closure without needing complex mechanical latches or snaps.
The clever bit
The genius was using the material's own flexibility to create a seal, rather than relying on a separate gasket or mechanical locking mechanism.
What it does not cover
- Does not cover rigid glass or metal containers that cannot flex to form a seal.
- Does not cover lids that require mechanical hinges or external clamps to stay closed.
- Does not cover containers made of non-polyethylene materials that lack the necessary flexibility.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Moderate
Citation count
40/40
Highly cited
Claim breadth
0/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$32K – $104K
Midpoint $65K · expired or expiring · industry ×0.9
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Concepts involved
Citations
Patent lineage
Cite this patent
Tupper, E. S. (1949). How Earl Tupper Invented the Airtight Plastic Food Container (U.S. Patent No. 2,487,400). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/2487400/tupperware-airtight-seal
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does How Earl Tupper Invented the Airtight Plastic Food Container cover?
A 1947 patent for a flexible plastic container with a unique, airtight lid that seals by pressing down on the center, creating the foundation for Tupperware.
Who owns patent US 2487400?
Individual owns this patent, granted in 1949.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 2487400 cited by?
This patent has been cited by 116 later patents that build on its ideas.
What problem does this patent solve?
This invention launched the food storage industry as we know it. By enabling an airtight seal in a lightweight, durable plastic, it changed how families stored leftovers and led to the iconic Tupperware party business model.
What does this patent NOT cover?
Does not cover rigid glass or metal containers that cannot flex to form a seal.
Same assignee
More from Individual
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