Patent US4350494A successfully refreshed from Google Patents.
US4350494A
Expired / Lapsed
US
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Process for the dyeing of textile material and apparatus for carrying out the process
Assignee: BASF Corp
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Filing: 1981-01-30
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Granted: 1982-09-21
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Expires: 2001-01-30
Abstract
Abstract Described is a process for the dyeing of textile material by the exhaust method, whereby the dyeing is commenced at a pH value of between 6 and 12 and terminated at a pH value of between 3 and 7, which process is characterized in that during dyeing the pH value is lowered, by the addition of an inorganic acid, by at least 1 unit of pH value; and that subsequent to the dyeing the exhausted bath, after the addition of alkali, dye and, if required, further auxiliaries, is optionally used afresh for dyeing. Furthermore an apparatus for carrying out this process is described which consists of a dyeing aggregate having a liquor-circulating system which contains at least one pH-measuring point as well as at least one dosing device.
Inventors
- 👤 Hans Scheidegger
- 👤 Hermann Flensberg
- 👤 Roland Bauhofer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:52
CPC Classifications
D; D06; D06P; D06P1/00; D06P1/0004; D06B; D06B23/00; D06B23/20; D06B23/205; D06P3/00; D06P3/02; D06P3/04; D06P3/06; Y; Y10; Y10S; Y10S8/00; Y10S8/929
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
127 words
In a process for the level dyeing of synthetic polyamide textile material by exhaustion in an aqueous dyebath using an anionic, metal-free, non-fiber-reactive dyestuff, the improvement which comprises (1) contacting the textile material with the dyebath at a pH value in the range of 6 to 12, (2) during the dyeing, exhausting the dyestuff onto the textile material by lowering the pH by at least one pH unit by the addition of an inorganic acid having a pKa value of less than 3.8 at 20° C., (3) separating the dyed textile material from the exhausted dyebath (4) adding to the exhausted dyebath additional dyestuff and sufficient alkali to adjust the dyebath pH value to the range of 6 to 12, and (5) repeating steps (1) and (2).
Claim 2
Dependent Claim
127 words
In a process for the level dyeing of synthetic polyamide textile material by exhaustion in an aqueous dyebath using an anionic, metal-free, non-fiber-reactive dyestuff, the improvement which comprises (1) contacting the textile material with the dyebath at a pH value in the range of 6 to 12, (2) during the dyeing, exhausting the dyestuff onto the textile material by lowering the pH by at least one pH unit by the addition of an inorganic acid having a pKa value of less than 3.8 at 20° C., (3) separating the dyed textile material from the exhausted dyebath (4) adding to the exhausted dyebath additional dyestuff and sufficient alkali to adjust the dyebath pH value to the range of 6 to 12, and (5) repeating steps (1) and (2).
Claim 3
Dependent Claim
13 words
The process of claim 1, wherein the synthetic polyamide textile material is carpeting.
Claim 4
Dependent Claim
15 words
Process according to claim 1, wherein the acid is added continuously at a constant rate.
Claim 5
Dependent Claim
14 words
Process according to claim 1, wherein the acid is added continuously at different rates.
Claim 6
Dependent Claim
13 words
Process according to claim 1, wherein the addition of acid is periodically discontinued.
Claim 7
Dependent Claim
38 words
Process according to claim 1, wherein the acid is so added that a constant change of the pH value relative to time or temperature occurs in such a manner that one or more linear or nonlinear gradients result.
Claim 8
Dependent Claim
10 words
Process according to claim 1, wherein sulphuric acid is used.
Claim 9
Dependent Claim
29 words
Process according to claim 1, wherein at the commencement of dyeing the pH value is brought to the initial value by the controlled addition of a strong alkaline solution.
Claim 10
Dependent Claim
24 words
Process according to claim 8, wherein there is used an alkaline solution of which the pK a value at 20° C. is above 9.2.
Claim 11
Dependent Claim
14 words
Process according to claim 1, wherein the bath is used two to six times.
References Cited (Backward Citations)
US3352624A
Cited
GB605258A
Cited
US2900218A
Cited
US3317271A
Cited
US3627473A
Cited
GB1404545A
Cited
DE2361491A1
Cited
GB1450216A
Cited
GB1458632A
Cited
US3936268A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-20 | 1986-03-22 | 1986-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-20 | 1990-03-22 | 1990-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-20 | 1994-03-22 | 1994-09-21 | $7700.00 | Window Closed / Lapsed |