Transfer assisted screen printing method of making shaped abrasive particles and the resulting shaped abrasive particles

• US 8,480,772 B2
• Filed: 06/30/2010
• Issued: 07/09/2013
• Est. Priority Date: 12/22/2009
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Welygan, Dennis G., Erickson, Dwight D., Boden, John T.
• Primary Examiner(s): Parvini, Pegah
• Application Number:
  US12/827,274
• Publication Number:
  US 20110146509A1
• Time in Patent Office: 1,105 Days
• Field of Search: 512/93, 513/07, 428/402
• US Class Current: 51/293
• CPC Class Codes: B01J 2/006 Coating of the granules without description of the process or the device by which the granules are obtained to prevent the granules sticking together B01J2/30
• CPC Class Codes: B01J 2/20 by expressing the material, e.g. through sieves and fragmenting the extruded length
• CPC Class Codes: B01J 2/26 on endless conveyor belts
• CPC Class Codes: B41M 1/12 Stencil printing; Silk-screen printing
• CPC Class Codes: C04B 35/10 based on aluminium oxide
• CPC Class Codes: C09K 3/1409 Abrasive particles per se preparation of diamond C01B32/25
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

Shaped ceramic articles can be obtained by screen printing the desired shapes from a dispersion of a precursor of the ceramic onto a receiving surface using a transfer assisted technique that applies a differential pressure, at least partially drying the screen printed shapes, and firing them to generate the shaped ceramic articles. Shaped abrasive particles made using lower viscosity sol gels that tended to flow or creep after the screen printing formation were found to have higher grinding performance over screen printed shaped abrasive particles made with higher viscosity sol gels.

Claims

1. Shaped abrasive particles comprising a post-formation flowed surface;

the shaped abrasive particles further comprising a first side, a second side, and a sidewall connecting the first side to the second side and wherein the sidewall comprises the post-formation flowed surface; and

wherein a Second Side to First Side Area Ratio of the shaped abrasive particles is between about 2.0 to about 10.0.

2. The shaped abrasive particles of claim 1 wherein the sidewall is concave.

3. The shaped abrasive particles of claim 2 wherein the sidewall comprises a first portion intersecting the first side and a second portion intersecting the second side and the slope of the first portion is greater than the slope of the second portion.

4. The shaped abrasive particles of claim 3 wherein the length of the first portion is less than the length of the second portion.

5. The shaped abrasive particles of claim 3 comprising an angle between the second portion and the second side and wherein the angle is between about 10 degrees to about 60 degrees.

6. The shaped abrasive particles of claim 1 comprising an angle between the sidewall and the second side and wherein the angle is between about 10 degrees to about 60 degrees.

7. The shaped abrasive particles of claim 6 wherein the Second Side to First Side Area Ratio is between about 2.0 to about 3.5.

8. The shaped abrasive particles of claim 1 wherein the first side is concave.

9. The shaped abrasive particles of claim 8 wherein a Thickness Ratio, Tc/Ti, is between about 1.20 to about 5.00, wherein Tc/Ti is the ratio of the average corner thickness over the average interior thickness.

10. The shaped abrasive particles of claim 1 having an aspect ratio of from about 2:

1 to about 50;

1.

11. The shaped abrasive particles of claim 1 comprising a generally triangular shape.

12. The shaped abrasive particles of claim 1 wherein the second side is textured.

13. Shaped abrasive particles comprising a first side, a second side, and a sidewall connecting the first side to the second side;

the sidewall comprising a first portion intersecting the first surface and a second portion intersecting the second surface and the slope of the first portion is greater than the slope of the second portion.

14. The shaped abrasive particles of claim 13 wherein the length of the first portion is less than the length of the second portion.

15. The shaped abrasive particles of claim 14 comprising an angle between the second portion and the second surface and wherein the angle is between about 10 degrees to about 60 degrees.

16. The shaped abrasive particles of claim 13 wherein a Second Side to First Side Area Ratio is between about 1.5 to about 10.0.

17. The shaped abrasive particles of claim 13 comprising an angle between the second portion and the second side and wherein the angle is between about 10 degrees to about 60 degrees.

18. The shaped abrasive particles of claim 17 wherein a Second Side to First Side Area Ratio is between about 1.5 to about 10.0.

19. The shaped abrasive particles of claim 13 wherein the first side is concave.

20. The shaped abrasive particles of claim 19 wherein a Thickness Ratio, Tc/Ti, is between about 1.20 to about 5.00, wherein Tc/Ti is the ratio of the average corner thickness over the average interior thickness.

21. The shaped abrasive particles of claim 13 having an aspect ratio of from about 2:

1 to about 50;

1.

22. The shaped abrasive particles of claim 13 comprising a generally triangular shape.

23. The shaped abrasive particles of claim 13 wherein the second side is textured.

24. The shaped abrasive particles of claim 13 wherein the sidewall comprises a post-formation flowed surface.

25. Shaped abrasive particles comprising a first side, a second side, and a sidewall connecting the first side to the second side;

and wherein the first side is concave and the sidewall is concave.

26. The shaped abrasive particles of claim 25 wherein the sidewall comprises a first portion intersecting the first side and a second portion intersecting the second side and the slope of the first portion is greater than the slope of the second portion.

27. The shaped abrasive particles of claim 26 wherein the length of the first portion is less than the length of the second portion.

28. The shaped abrasive particles of claim 25 wherein the second side is textured.

29. The shaped abrasive particles of claim 25 wherein a Thickness Ratio, Tc/Ti, is between about 1.20 to about 5.00, wherein Tc/Ti is the ratio of the average corner thickness over the average interior thickness.

30. The shaped abrasive particles of claim 25 wherein a Second Side to First Side Area Ratio is between about 1.5 to about 10.0.

31. The shaped abrasive particles of claim 25 having an aspect ratio of from about 2:

1 to about 50;

1.

32. The shaped abrasive particles of claim 25 comprising a generally triangular shape.