How Play-Doh Was Invented
The original 1965 patent for the soft, non-toxic modeling compound known as Play-Doh, detailing a specific mixture of flour, water, salt, and kerosene.
Original patent title: “Plastic modeling composition of a soft, pliable working consistency”
The original 1965 patent for the soft, non-toxic modeling compound known as Play-Doh, detailing a specific mixture of flour, water, salt, and kerosene. Granted to Rainbow Crafts Inc in 1965 with 2 claims and 29 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
The patent defines a specific chemical mixture that creates a soft, pliable, and non-sticky modeling clay. The composition relies on a precise ratio of grain flour, water, a water-soluble inorganic chlorine salt, and a small amount of kerosene. This combination allows the material to remain lump-free and re-workable over long periods without drying out or becoming toxic to children. By balancing these ingredients, the inventors created a substance that holds its shape when molded but remains soft enough for easy manipulation.
The gap
What does this patent NOT cover?
- Does not cover modeling compounds that exclude the specific range of kerosene as a lubricant.
- Does not cover clay-based modeling materials that do not use grain flour as the primary base.
- Does not cover mixtures that omit the water-soluble inorganic chlorine salt.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The inclusion of kerosene acts as a subtle lubricant and preservative, preventing the flour-and-water mixture from becoming sticky or developing mold while maintaining a velvety texture.
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
Play-Doh modeling compound
Why it matters
The bigger picture
This patent protected the formula for Play-Doh, which became one of the most successful children's toys in history. It transformed a product originally intended for cleaning wallpaper into a global cultural staple for creative play.
Filed
May 17, 1960
Granted
January 26, 1965
Market context
Who's building on this
Companies in this space
Hasbro, which acquired the Play-Doh brand, continues to manufacture and iterate on the product line. Many competitors in the modeling clay market have since developed non-toxic, flour-based alternatives that iterate on the basic principles of this original formula.
Market impact
The patent secured a monopoly on a specific, highly successful toy category, allowing the inventors to build a massive brand. It effectively defined the standard for non-toxic, reusable modeling materials in the toy industry for decades.
Claim 1 — Plain English
What this patent covers
The patent defines a specific chemical mixture that creates a soft, pliable, and non-sticky modeling clay. The composition relies on a precise ratio of grain flour, water, a water-soluble inorganic chlorine salt, and a small amount of kerosene. This combination allows the material to remain lump-free and re-workable over long periods without drying out or becoming toxic to children. By balancing these ingredients, the inventors created a substance that holds its shape when molded but remains soft enough for easy manipulation.
The clever bit
The inclusion of kerosene acts as a subtle lubricant and preservative, preventing the flour-and-water mixture from becoming sticky or developing mold while maintaining a velvety texture.
What it does not cover
- Does not cover modeling compounds that exclude the specific range of kerosene as a lubricant.
- Does not cover clay-based modeling materials that do not use grain flour as the primary base.
- Does not cover mixtures that omit the water-soluble inorganic chlorine salt.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Early stage
Citation count
29/40
Moderately cited
Claim breadth
1/20
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
$26K – $83K
Midpoint $52K · expired or expiring · industry ×2.4
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
2 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Mcvicker, N. W., & Mcvicker, J. S. (1965). How Play-Doh Was Invented (U.S. Patent No. 3,167,440). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/3167440/play-doh-modeling-compound
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 Play-Doh Was Invented cover?
The original 1965 patent for the soft, non-toxic modeling compound known as Play-Doh, detailing a specific mixture of flour, water, salt, and kerosene.
Who owns patent US 3167440?
Rainbow Crafts Inc owns this patent, granted in 1965.
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 3167440 cited by?
This patent has been cited by 29 later patents that build on its ideas.
What problem does this patent solve?
This patent protected the formula for Play-Doh, which became one of the most successful children's toys in history. It transformed a product originally intended for cleaning wallpaper into a global cultural staple for creative play.
What does this patent NOT cover?
Does not cover modeling compounds that exclude the specific range of kerosene as a lubricant.
Patent monitoring