Claims
- 1. A method of improving the bleaching performance of a peroxide comprising the step of applying a bleaching solution to a substrate, the bleaching solution comprising (i) from about 0.1% to about 10% by weight of a lactone represented by the formula (I): ##STR3## wherein R.sub.1 and R.sub.2 are independently selected from the group consisting of hydrogen, alkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, aryl, and aralkyl and Q is an alkylene radical having 2 to 4 carbon atoms, any carbons of which may be substituted by any of an alkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, alkene having 1 to 6 carbon atoms, aryl, aralkyl and hydroxy (ii) from about 1% to about 10% by weight of hydrogen peroxide; (iii) an effective amount of at least one alkaline agent to provide said solution with a pH of at least about 7; and (iv) the balance comprising a solvent, wherein said lactone is present in an amount effective to increase a bleaching rate of the bleaching solution compared to the bleaching solution if said lactone were absent.
- 2. The method according to claim 1, wherein the peroxide is present in an amount in the range of from about 1.0% to about 5.0% by weight.
- 3. The method as claimed in claim 1, wherein the peroxide is present in an mount in the range of from about 2.0% to about 4.0% by weight.
- 4. The method according to claim 1, wherein Q is an alkylene radical having 2 to 3 carbon atoms.
- 5. The method according to claim 1 wherein the R.sub.1 and R.sub.2 are hydrogen.
- 6. The method according to claim 1 wherein the lactone is delta-valerolactone or gamma-butyrolactone.
- 7. The method according to claim 1 wherein the at least one alkaline agent is selected from the group consisting of alkali metal carbonates, alkali metal silicates, alkali metal borates, alkali metal phosphates, alkali metal hydroxides, alkaline earth carbonates, alkaline earth hydroxides, alkaline earth oxides, ammonia, ethanolamines, sodium glycinate and mixtures thereof.
- 8. The method according to claim 1 wherein the at least one alkaline agent is selected from the group consisting of sodium carbonate, sodium bicarbonate, potassium carbonate, sodium carbonate and mixtures thereof.
- 9. The method according to claim 1, wherein the pH is in a range from about 7 to about 13.
- 10. The method according to claim 1, wherein the bleaching solution further comprises an amount of acid in the range from about 0.01 to about 1 weight percent, based on the total weight of the solution.
- 11. The method according to claim 1, wherein the acid is selected from the group consisting of citric acid, acetic acid, hydroxyacetic acid, lactic acid, malic acid, sulfamic acid, sulfuric acid, phosphoric acid and mixtures thereof.
- 12. The method according to claim 1, wherein the solvent is water.
- 13. The method according to claim 1 wherein the bleaching solution comprises (i) gamma-butyrolactone in an amount from about 0.1 to about 10 weight percent, based on the total weight of the solution, (ii) hydrogen peroxide in an amount from about 1 to about 10 weight percent, based on the total weight of the solution and (iii) an effective amount of an alkaline agent to provide said solution with a pH of at least about 7, wherein said alkaline agent is selected from the group consisting of sodium bicarbonate, sodium carbonate, potassium bicarbonate, potassium carbonate and mixtures thereof.
- 14. A method for preparing a bleaching solution comprising the steps of combining (i) from about 0.1% to about 10% by weight of a lactone represented by the formula (I): ##STR4## wherein R.sub.1 and R.sub.2 are independently selected from the group consisting of hydrogen, alkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, aryl, and aralkyl; and Q is an alkylene radical having 2 to 4 carbon atoms, any carbons of which may be substituted by any of an alkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, alkene having 1 to 6 carbon atoms, aryl, aralkyl and hydroxy, and (ii) from about 1% to about 10% by weight of hydrogen peroxide; and then adding (iii) an amount of at least one alkaline agent effective to form said bleaching solution having a pH of at least about 7; and (iv) the balance comprising a solvent, wherein said lactone is present in an amount effective to increase a bleaching rate of the bleaching solution compared to the bleaching solution if said lactone were absent.
- 15. The method according to claim 14, wherein Q is an alkylene radical having 2 to 3 carbon atoms.
- 16. The method according to claim 14, wherein R.sub.1 and R.sub.2 are hydrogen.
- 17. The method according to claim 14, wherein the lactone is gamma-butyrolactone or delta-valerolactone.
- 18. The method according to claim 14, wherein the pH is in a range from about 7 to about 13.
- 19. The method according to claim 14, further comprising the step of adding an acid to the lactone/peroxide mixture.
- 20. The method according to claim 19, wherein the acid is selected from the group consisting of citric acid, acetic acid, hydroxyacetic acid, lactic acid, malic acid, sulfamic acid, sulfuric acid, phosphoric acid and mixtures thereof.
Parent Case Info
This application is a continuation of application Ser. No. 08/346,597 filed Nov. 29, 1994 now abandoned.
US Referenced Citations (8)
Foreign Referenced Citations (4)
Number |
Date |
Country |
3206093 |
Sep 1983 |
DEX |
4231466 |
Mar 1994 |
DEX |
4-91271 |
Mar 1994 |
JPX |
836988 |
Feb 1956 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
346597 |
Nov 1994 |
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