Granted Patent B1

US 9,447,368 · App. 14/554,415 · Granted Sep 20, 2016

Abstract

Claims (35)

1. A detergent composition for removing contaminants from a surface, wherein in the absence of water the composition comprises the following components by weight:

1%-5% ethylene oxide/propyleneoxide (EO/PO);

10%-15% sodium-2-ethylhexyliminodipropionate;

25%-30% potassium hydroxide (KOH);

20%-25% hydroxyethylene diphosphonic acid (HEDP);

30%-35% diethylenetriamine-penta(methylene phosphonic acid) (DTPMP); and

1%-5% oxalic acid.

2. An aqueous solution comprising water and the detergent composition of claim 1 , wherein the aqueous solution comprises between 0.01% and 3.5% by weight of each of the following components: EO/PO, sodium-2-ethylhexyliminodipropionate, KOH, HEDP, DTPMP, and oxalic acid.

3. The aqueous solution of claim 2 , comprising by weight:

0.01%-0.5% ethylene oxide/propyleneoxide (EO/PO);

0.1%-1.5% sodium-2-ethylhexyliminodipropionate;

0.25%-3.0% potassium hydroxide (KOH);

0.20%-2.5% hydroxyethylene diphosphonic acid (HEDP);

0.3%-3.5% diethylenetriamine-penta(methylene phosphonic acid) (DTPMP); and

0.01%-0.5% oxalic acid.

4. The aqueous solution of claim 2 , wherein the solution has a pH of between 11.3 and 12.3.

5. The aqueous solution of claim 4 , wherein the solution has a pH of 11.8.

6. The aqueous solution of claim 2 , wherein the solution has a surface tension of between 32.7 mN/m and 42.7 mN/m.

7. The aqueous solution of claim 2 , wherein the solution has a surface tension of 37.7 mN/m.

8. The aqueous solution of claim 2 , wherein the solution has a cloud point of >60° C.

9. The detergent composition of claim 1 , wherein the contaminants comprise elements selected from the group consisting of nickel, aluminum, silicon, oxygen and phosphorus.

10. The detergent composition of claim 9 , wherein the contaminants are particles selected from the group consisting of nickel oxide (NiO), nickel phosphorous (NiP), silica oxide (SiO), and AlSiO.

11. The detergent composition of claim 1 , wherein the surface is a surface of a hard disk.

12. The aqueous solution of claim 11 , wherein the surface of the hard disk is plated with an element selected from the group consisting of nickel and phosphorous.

13. A method of cleaning a surface of a hard disk, comprising the steps of:

(a) providing the hard disk, wherein the surface of the hard disk comprises contaminants;

(b) providing an aqueous solution comprising the detergent composition of claim 1 ;

(c) contacting the surface of the hard disk with the aqueous solution, wherein at least some of the contaminants are removed from the surface of the hard disk and are transferred into the aqueous solution; and

(d) removing the aqueous solution from the surface of the hard disk.

14. The method of claim 13 , wherein the surface of the hard disk comprises an element selected from the group consisting of nickel and phosphorous.

15. The method of claim 13 , wherein the contaminants comprise elements selected from the group consisting of nickel, aluminum, silicon, oxygen and phosphorus.

16. The method of claim 13 , wherein the contaminants are particles selected from the group consisting of nickel oxide (NiO), nickel phosphorous (NiP), silica oxide (SiO), and AlSiO.

17. The method of claim 13 , wherein the aqueous solution comprises between 0.01% and 3.5% by weight of each of the following: EO/PO, sodium-2-ethylhexyliminodipropionate, KOH, HEDP, DTPMP, and oxalic acid.

18. The method of claim 13 , wherein the step of contacting the surface of the hard disk with the aqueous solution is accomplished by dipping the platter into the aqueous solution or by spraying the platter with the aqueous solution.

19. The method of claim 13 , further comprising the step of rinsing the hard disk with deionized water after removing the aqueous solution from the surface of the hard disk.

Assignments (8)