GB Patent

GB500489A — Improvements in or relating to the manufacture of water-soluble hyposulphites

Assigned to IG Farbenindustrie AG · Expires 1939-02-09 · 87y expired

What this patent protects

500,489. Purifying hyposulphites. I. G. FARBENINDUSTRIE. AKT.-GES. Aug 9, 1937, No. 21905. Convention date, Aug. 7, 1936. [Class 1 (iii)] Hyposulphite solution prepared by the action of alkali metal amalgam on solutions of bisulphites or sulphurous acid, for instance sodium hypos…

USPTO Abstract

500,489. Purifying hyposulphites. I. G. FARBENINDUSTRIE. AKT.-GES. Aug 9, 1937, No. 21905. Convention date, Aug. 7, 1936. [Class 1 (iii)] Hyposulphite solution prepared by the action of alkali metal amalgam on solutions of bisulphites or sulphurous acid, for instance sodium hyposulphite solution, is, freed from mercury by the action of an adsorbent. Adsorptive carbon, fuller's earth, silica gel, alumina gel and iron oxide gel may be used, or an adsorptive precipitate of, for instance, copper or zinc sulphides, or iron or aluminium hydroxide may be formed in the solution. The hydrated salt may be precipitated by alcohol.

Drugs covered by this patent

Patent Metadata

Patent number
GB500489A
Jurisdiction
GB
Classification
—
Expires
1939-02-09
Drug substance claim
No
Drug product claim
No
Assignee
IG Farbenindustrie AG
Source
FDA Orange Book + USPTO grounding via Google Patents

Bibliographic data sourced from FDA Orange Book + USPTO public records. Plain-English summary generated by AI grounded in source text. Patent term extensions (PTR, SPC, pediatric) may shift the effective expiry. Not legal advice.

Track this patent

Get a daily-checked alert when vulnerability score, expiry, classification, or assignee changes. Email, Slack, or Teams delivery. Pro: 50 watches, Free: 3.