US4552849A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for determination of formaldehyde
Assignee: Kikkoman Corp
•
Filing: 1984-07-18
•
Granted: 1985-11-12
•
Expires: 2004-07-18
Abstract
Abstract In a method of formaldehyde determination by measuring the fluorescence of a fluorescent substance formed by the reaction of a formaldehyde-containing solution with a fluorescent reagent capable of forming said fluorescent substance by the reaction with formaldehyde, the improvement which comprises using as said fluorescence reagent a compound represented by the general formula CH 3 C(NH 2 )═CHCO 2 R, wherein R represents an alkyl group having 1 to 4 carbon atoms.
Inventors
- 👤 Motoo Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:11
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/62; G01N21/63; G01N21/64; G01N21/6428; G01N21/643; Y; Y10; Y10T; Y10T436/00; Y10T436/20; Y10T436/200833; Y10T436/202499
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
72 words
In a method of formaldehyde determination by measuring the fluorescence of a fluorescent substance formed by the reaction of a formaldehyde-containing solution with a fluorescence reagent capable of forming said fluorescent substance by the reaction with formaldehyde, the improvement which comprises using as said fluorescence reagent a compound represented by the general formula CH 3 C(NH 2 )═CHCO 2 R, wherein R represents an alkyl group having 1 to 4 carbon atoms.
Claim 2
Dependent Claim
72 words
In a method of formaldehyde determination by measuring the fluorescence of a fluorescent substance formed by the reaction of a formaldehyde-containing solution with a fluorescence reagent capable of forming said fluorescent substance by the reaction with formaldehyde, the improvement which comprises using as said fluorescence reagent a compound represented by the general formula CH 3 C(NH 2 )═CHCO 2 R, wherein R represents an alkyl group having 1 to 4 carbon atoms.
Claim 3
Dependent Claim
21 words
A method according to claim 1, wherein a compound of said general formula wherein R is a methyl group is used.
Claim 4
Dependent Claim
21 words
A method according to claim 1, wherein a compound of said general formula wherein R is an ethyl group is used.
Claim 5
Independent Claim
114 words
A method of formaldehyde determination which comprises mixing a formaldehyde-containing sample solution with an equal amount of a phosphate or ammonium acetate buffer solution which has been adjusted to a concentration of 0.01 to 3 in molarity and a pH of 4 to 8, adding to the mixture 1 to 50% of a 0.01 to 2 molar solution of methyl 3-aminocrotonate, CH 3 C(NH 2 )═CHCO 2 CH 3 , or ethyl 3-aminocrotonate, CH 3 C(NH 2 )═CHCO 2 C 2 H 5 , in an organic solvent, allowing the resulting mixture to react at 20 to 80° C. for 1 to 60 minutes, and then determining the fluorescence of the resulting fluorescent substance.
Claim 6
Independent Claim
114 words
A method of formaldehyde determination which comprises mixing a formaldehyde-containing sample solution with an equal amount of a phosphate or ammonium acetate buffer solution which has been adjusted to a concentration of 0.01 to 3 in molarity and a pH of 4 to 8, adding to the mixture 1 to 50% of a 0.01 to 2 molar solution of methyl 3-aminocrotonate, CH 3 C(NH 2 )═CHCO 2 CH 3 , or ethyl 3-aminocrotonate, CH 3 C(NH 2 )═CHCO 2 C 2 H 5 , in an organic solvent, allowing the resulting mixture to react at 20 to 80° C. for 1 to 60 minutes, and then determining the fluorescence of the resulting fluorescent substance.
References Cited (Backward Citations)
JPS5113034A
Cited
US4438206A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-11 | 1989-05-13 | 1989-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-11 | 1993-05-13 | 1993-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-11 | 1997-05-13 | 1997-11-12 | $7700.00 | Window Closed / Lapsed |