US4770706A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aqueous ink and process for its manufacture
Assignee: Pelikan International Corp Bhd
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Filing: 1987-10-28
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Granted: 1988-09-13
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Expires: 2007-10-28
Abstract
Abstract The invention relates to an aqueous ink for writing, drawing, or marking, which has as a dispersion stabilizer a degradation product of gelatin made by enzymatic action of a protease. The process of the invention is carried out by subjecting an aqueous gelatin solution to degradation by an enzyme, then inhibiting the enzyme, such as by heating to 90 degrees C. or above, before the degradation has proceeded to products which no longer have activity as dispersion stabilizers. Subsequently, colorants such as pigments can be added along with other desired additives.
Inventors
- 👤 Gunter Pietsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:55
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/16; C09D11/17
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
25 words
An aqueous ink comprising water, colorant, and dispersion stabilizer, wherein said dispersion stabilizer is a colloidally dissolved product of the controlled enzymatic degradation of gelatin.
Claim 2
Dependent Claim
25 words
An aqueous ink comprising water, colorant, and dispersion stabilizer, wherein said dispersion stabilizer is a colloidally dissolved product of the controlled enzymatic degradation of gelatin.
Claim 3
Dependent Claim
13 words
An ink as defined in claim 1 wherein the colorant is a pigment.
Claim 4
Dependent Claim
42 words
A process for the production of an aqueous ink which comprises degrading an aqueous gelatin solution by means of a gelatin-degrading enzyme, inhibiting the action of the enzyme before the formation of degradation products inactive as dispersion stabilizers, and then adding colorants.
Claim 5
Dependent Claim
42 words
A process for the production of an aqueous ink which comprises degrading an aqueous gelatin solution by means of a gelatin-degrading enzyme, inhibiting the action of the enzyme before the formation of degradation products inactive as dispersion stabilizers, and then adding colorants.
Claim 6
Dependent Claim
30 words
A process in accordance with claim 3 in which the inhibition of the action of the enzyme is carried out by heating the solution to at least 90 degrees C.
Claim 7
Dependent Claim
31 words
A process in accordance with claim 3 in which the inhibition of the action of the enzyme is carried out by heating the solution at about 95 to 100 degrees C.
Claim 8
Dependent Claim
65 words
A process in accordance with claim 3 wherein the starting gelatin solution has a concentration in the range of about 10 to 60 weight % gelatin, the degradation time is in the range of about 30 minutes to 3 hours, the degradation temperature is in the range of about 40 to 70 degrees, and the enzyme is a protease used in an effective gelatin-degrading amount.
Claim 9
Dependent Claim
19 words
A process in accordance with claim 6 where the protease is present at about 0.05 to 1 weight %.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-13 | 1992-03-14 | 1992-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-13 | 1996-03-14 | 1996-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-13 | 2000-03-14 | 2000-09-13 | $7700.00 | Window Closed / Lapsed |