Skip to content
PatentBrief
US 1721815Freedom to Build
Public domain since 1947

You can freely build on How the First Cotton Swabs Were Mass-Produced

This patent expired in 1947. Every claim — 0 independent, 0 dependent — is now unenforceable. Anyone can use, reproduce, manufacture, sell, or offer for sale this technology without a license.

Original assignee

Individual

Patent granted

1929

Expired

1947

Forward citations

10

What this patent covers

This patent describes a mechanical process for attaching absorbent cotton to the ends of small wooden sticks. It outlines an apparatus that automates the winding and securing of cotton fibers onto a stick, ensuring a consistent shape and density. By moving away from manual assembly, the invention allowed for the high-speed production of sanitary medical swabs that could be packaged and sold for home use.

What is now free to use

All 0 claims of US 1721815 are in the public domain. Specifically:

    The 0 dependent claims add narrowing limitations and are also free.

    What is NOT covered

    Patent expiry frees this specific invention. Separately-patented improvements made after expiry may still be protected.

    • Does not cover the chemical composition of the cotton fibers themselves.

    • Does not cover the use of plastic or paper stems, as the patent focuses on the mechanical winding process for wooden applicators.

    • Does not cover the medical application or diagnostic use of the swabs.

    Who is building on this today

    Unilever, which acquired the Q-Tip brand, continues to refine high-speed manufacturing processes for personal care products. Various medical supply manufacturers also utilize advanced versions of these automated winding techniques for sterile diagnostic tools.

    Products built on expired version of this technology

    Q-Tip cotton swabs

    Generic cotton-tipped applicators

    Medical diagnostic swabs

    How to cite this patent in your documentation

    Individual. US Patent 1721815. Process and apparatus for manufacturing medical swabs. Granted 1929, expired 1947. Now in the public domain.

    Note: This is a convenience citation. Consult a patent attorney for formal freedom-to-operate analysis.

    PatentBrief is an educational resource and does not provide legal advice. Patent expiration information is derived from USPTO records and may not reflect continuation patents, divisional filings, or separately-patented improvements. For commercial use or production decisions, obtain a formal freedom-to-operate (FTO) opinion from a registered patent attorney.

    ← Full patent detailsMore public domain patents →