Claims
- 1. A method for bleaching cellulose fibers and blends thereof with synthetic fibers, comprising the step of bleaching said fibers with an alkaline, peroxide-containing bleaching liquor, wherein such a bleaching liquor contains, as a peroxide stabilizing agent, between about 4% and about 30% of an N-(hydroxy methyl)-1-amino alkane-1,1-diphosphonic acid corresponding to the formula ##STR2## wherein R represents hydrogen or alkyl with 1 to 3 carbon atoms, and
- R.sub.1 represents hydrogen or the hydroxy methyl group (--CH.sub.2 OH), and the water-soluble salts of said acid, said amount being calculated based on the content of 35% hydrogen peroxide present in the bleaching liquor.
- 2. A bleaching method according to claim 1, wherein the bleaching liquor contains, as a stabilizing agent, an N-(hydroxy methyl)-1-amino ethane-1,1-diphosphonic acid, an N,N-Bis-(hydroxy methyl)-1-amino ethane-1,1-diphosphonic acid or a mixture thereof.
- 3. A bleaching method according to claim 1, wherein the bleaching liquor contains, as a stabilizing agent N-(hydroxy methyl)amino methane diphosphonic acid, N,N-Bis-(hydroxy methyl)amino methane diphosphonic acid or a mixture thereof.
- 4. A bleaching method according to claim 1, wherein the bleaching liquor contains, as a stabilizing agent N-(hydroxy methyl)-1-amino propane-1,1-diphosphonic acid, N,N-Bis-(hydroxy methyl)-1-amino propane-1,1-diphosphonic acid or a mixture thereof.
- 5. A bleaching method according to claim 1, wherein the bleaching liquor contains, as a stabilizing agent N-(hydroxy methyl)-1-amino butane-1,1-diphosphonic acid, N,N-Bis-(hydroxy methyl)-1-amino butane-1,1-diphosphonic acid or a mixture thereof.
- 6. A bleaching method according to claim 1, wherein the amount of stabilizing phosphonic acid is between about 6% and about 15%, calculated based on the amount of 35% hydrogen peroxide present in the bleaching liquor.
- 7. A bleaching method according to claim 1, wherein the bleaching liquor additionally contains an N,N-Bis-(hydroxy alkyl)-1-amino alkane-1,1-diphosphonic acid, wherein the alkyl group of said acid contains 1 to 3 carbon atoms.
- 8. A bleaching method according to claim 1, wherein the bleaching liquor additionally contains a compound selected from the group consisting of an alkali metal gluconate, boric acid, and a mixture thereof.
- 9. A bleaching method according to claim 1, wherein said method is carried out at room temperature.
- 10. A bleaching method according to claim 1, wherein the hydrogen peroxide-stabilizing phosphonic acid comprises N,N-Bis-(hydroxy methyl)-1-amino ethane-1,1-diphosphonic acid.
- 11. A bleaching method according to claim 1, wherein the hydrogen peroxide-stabilizing phosphonic acid comprises N-(hydroxy methyl)-1-amino ethane-1,1-diphosphonic acid.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2933969 |
Aug 1979 |
DEX |
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Parent Case Info
This is a division of application Ser. No. 374,683, filed May 4, 1982, which is a division of application of Ser. No. 177,885, filed Aug. 14, 1980, now U.S. Pat. No. 4,337,214, issued June 29, 1982.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
568570 |
Jan 1959 |
CAX |
66894 |
Dec 1982 |
EPX |
Divisions (2)
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Number |
Date |
Country |
Parent |
374683 |
May 1982 |
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Parent |
177885 |
Aug 1980 |
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