Claims
- 1. A bleaching system for forming an acidic bleaching solution comprising (a) a first vessel containing a first aqueous solution having a pH of about 6 or less comprising:
- (i) a chlorine deactivating agent; and
- (ii) a non-oxidizable acid; and
- (b) a second vessel containing a second aqueous solution having a pH of about 10 or greater comprising:
- (i) a hypochlorite salt having 7% by weight or less of residual chloride ion; and
- (ii) a thickening agent,
- wherein said bleaching system require when said first aqueous solution and said second aqueous solution are admixed from said first vessel and said second vessel, respectively, said admixture has a molar ratio of hypochlorite ion to chlorine deactivating agent of about 3.6:1 to about 2.5:1 and said admixture has a pH of about 6 or less.
- 2. A bleaching system according to claim 1, wherein said first vessel and said second vessel are united in a single container.
- 3. A bleaching system according to claim 1, wherein said chlorine deactivating agent is sulfamic acid or a salt thereof.
- 4. A bleaching system according to claim 3, wherein said non-oxidizable acid is selected from the group consisting of succinic acid, adipic acid and oxalic acid.
- 5. A bleaching system according to claim 4, wherein said residual chloride ion content of said hypochlorite salt is less than 1.0% by weight of said hypochlorite salt.
- 6. A bleaching system according to claim 5, wherein said second aqueous solution comprises a polyacrylate thickening agent.
- 7. A bleaching system according to claim 6, wherein said molar ratio of hypochlorite ion capable of admixture with said sulfamic acid or salt thereof is about 3.4:1 to about 2.8:1.
- 8. A bleaching system according to claim 7, wherein the pH of said acidic bleaching solution is about 4 to about 5.
- 9. A method for preparing an acidic bleaching solution comprising the step of combining (a) a first aqueous solution having a pH of about 6 or less comprising:
- (i) a chlorine deactivating agent; and
- (ii) a non-oxidizable acid; and
- (b) a second aqueous solution having a pH of about 10 or greater comprising:
- (i) a hypochlorite salt having 7% by weight or less of residual chloride ion; and
- (ii) a thickening agent,
- wherein said acidic bleaching solution has a pH of about 6 or less and a molar ratio of hypochlorite ion mixed with said chlorine deactivating agent is about 3.6:1 to about 2.5:1.
- 10. A method according to claim 9, wherein said chlorine deactivating agent is sulfamic acid or a salt thereof.
- 11. A method according to claim 10, wherein said non-oxidizable acid is selected from the group consisting of succinic acid, adipic acid and oxalic acid.
- 12. A method according to claim 11, where said residual chloride ion content of said of said hypochlorite salt is less than 1.0% by weight of said hypochlorite salt.
- 13. A method according to claim 12, wherein said second aqueous solution comprises a polyacrylate thickening agent.
- 14. A method according to claim 13, wherein said molar ratio of hypochlorite ion mixed with said sulfamic acid or salt thereof is about 3.4:1 to about 2.8:1.
- 15. A method according to claim 14, wherein the pH of said acidic bleaching solution is about 4 to about 5.
Parent Case Info
This application is a division of U.S. patent application Ser. No. 08/747,491, filed Nov. 12, 1996, now U.S. Pat. No. 5,911,909.
US Referenced Citations (11)
Foreign Referenced Citations (4)
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932750 |
Sep 1961 |
GBX |
2078522 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
747491 |
Nov 1996 |
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