US4138216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for monitoring ethylene oxide sterilization process
Assignee: Pymah Corp
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Filing: 1977-12-23
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Granted: 1979-02-06
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Expires: 1997-12-23
Abstract
Abstract A device for monitoring ethylene oxide sterilization processes comprising a wick means impregnated with an ethylene oxide responsive chemical compound, a pH sensitive dye and a quantifier mounted on a backing strip and sealed with a cover strip to form an envelope having one edge at which the wick means is exposed. The device is responsive to time, temperature and relative humidity as well as ethylene oxide concentration.
Inventors
- 👤 Raymond P. Larsson
- 👤 Robert J. Witonsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:32
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; G01N31/226; Y; Y10; Y10S; Y10S252/00; Y10S252/962; Y10T; Y10T436/00; Y10T436/20; Y10T436/200833
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
82 words
A device for monitoring an ethylene oxide sterilization process which comprises: (a) a wick means said wick means being impregnated with an ethylene oxide responsive chemical compound, a pH sensitive dye and a quantifier; (b) a backing strip upon which the wick means is mounted; and (c) a cover strip comprising an ethylene oxide impervious film adhered to said backing strip thereby forming an envelope enclosing said wick means, the wick means having one end exposed along one edge of said envelope.
Claim 2
Independent Claim
82 words
A device for monitoring an ethylene oxide sterilization process which comprises: (a) a wick means said wick means being impregnated with an ethylene oxide responsive chemical compound, a pH sensitive dye and a quantifier; (b) a backing strip upon which the wick means is mounted; and (c) a cover strip comprising an ethylene oxide impervious film adhered to said backing strip thereby forming an envelope enclosing said wick means, the wick means having one end exposed along one edge of said envelope.
Claim 3
Dependent Claim
18 words
The device of claim 1 wherein the quantifier is tartaric acid, oxalic acid, citric acid or sodium bisulfate.
Claim 4
Dependent Claim
19 words
The device of claim 1 wherein the cover strip is adhered to the backing strip using an acrylic adhesive.
Claim 5
Dependent Claim
18 words
The device of claim 1 wherein the cover strip is adhered to the backing strip by heat sealing.
Claim 6
Dependent Claim
24 words
The device of claim 1 wherein the envelope comprises a continuous piece of ethylene oxide impervious film folded upon itself to form said envelope.
Claim 7
Dependent Claim
55 words
The device of claim 1 wherein (a) the ethylene oxide responsive chemical compound is MgCl 2 .6H 2 O; (b) the ethylene oxide impervious cover strip is a ethylene glycol-terephthalic acid polyester; (c) the pH sensitive dye is bromphenol blue; (d) the quantifier is tartaric acid; and (e) the wick means comprises a paper strip.
Claim 8
Dependent Claim
22 words
The device of claim 1 wherein the chemical compound is MgCl 2 , FeCl 2 , ZnCl 2 or the hydrates thereof.
Claim 9
Dependent Claim
14 words
The device of claim 7 wherein the compound is MgCl 2 .6H 2 O.
Claim 10
Dependent Claim
20 words
The device of claim 1 wherein the pH sensitive dye has at least one pKa value of less than 7.
Claim 11
Dependent Claim
16 words
The device of claim 9 wherein the dye is bromphenol blue, thymol blue or xylenol blue.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-05 | 1982-08-07 | 1983-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-05 | 1986-08-07 | 1987-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-05 | 1990-08-07 | 1991-02-06 | $7700.00 | Window Closed / Lapsed |