Abrasive particles, method of making abrasive particles, and abrasive articles

Patent metadata

Field	Value
Publication number	US-12275884-B2
Application number	US-202418443791-A
Country	US
Kind code	B2
Filing date	Feb 16, 2024
Priority date	Apr 4, 2012
Publication date	Apr 15, 2025
Grant date	Apr 15, 2025

Abstract

Shaped ceramic abrasive particles include a first surface having a perimeter having a perimeter comprising at least first and second edges. A first region of the perimeter includes the second edge and extends inwardly and terminates at two corners defining first and second acute interior angles. The perimeter has at most four corners that define acute interior angles. A second surface is disposed opposite, and not contacting, the first surface. A peripheral surface is disposed between and connects the first and second surfaces. The peripheral surface has a first predetermined shape. Methods of making the shaped ceramic abrasive particles, and abrasive articles including them are also disclosed.

First claim

What is claimed is:

1. A coated abrasive article comprising a backing and an abrasive layer, wherein the abrasive layer comprises a plurality of abrasive particles secured to a major surface of the backing by a make layer and a size layer, wherein the plurality of abrasive particles comprises shaped ceramic abrasive particles each comprising:
a first surface having a generally triangular perimeter having three corners and at least two inwardly extending regions, wherein at least one inwardly extending region comprises two substantially straight edges, wherein each inwardly extending region terminates at two of the three corners of the perimeter, and wherein at least two of the three corners defines an acute interior angle in a range from 30 degrees to 50 degrees;
a second surface opposite, but not contacting, the first surface, wherein the second surface has substantially the same shape as the first surface; and
a peripheral surface disposed between and connecting the first and second surfaces;
wherein at the inwardly extending regions have a maximum depth that is that is between 5 percent and 15 percent of a maximum dimension of the shaped ceramic abrasive particle parallel to the maximum depth;
wherein the shaped ceramic abrasive particles consist essentially of a ceramic material, wherein the ceramic material comprises alpha alumina.

2. The coated abrasive article of claim 1 , wherein the generally triangular perimeter comprises three inwardly extending regions, and wherein the three corners each define an acute interior angle in a range from 30 degrees to 50 degrees.

3. The coated abrasive article of claim 2 , wherein the three corners each define an acute interior angle in a range from 35 degrees to 50 degrees.

4. The coated abrasive article of claim 3 , wherein the three corners each define an acute interior angle in a range from 40 degrees to 50 degrees.

5. The coated abrasive article of claim 1 , wherein the plurality of abrasive particles comprises, on a numerical basis, at least 10 percent of the shaped ceramic abrasive particles, wherein the shaped ceramic abrasive particles are sized according to an abrasives industry recognized specified nominal grade.

6. The coated abrasive article of claim 5 wherein the plurality of abrasive particles comprises at least 50 percent of the shaped ceramic abrasive particles.

7. The coated abrasive article of claim 6 wherein the plurality of abrasive particles comprises at least 90 percent of the shaped ceramic abrasive particles.

8. The coated abrasive article of claim 7 , wherein the plurality of abrasive particles comprises at least 95 percent of the shaped ceramic abrasive particles.

9. The coated abrasive article of claim 1 , wherein the abrasive layer further comprises a supersize coat applied over the plurality of abrasive particles.

10. The coated abrasive article of claim 1 , wherein the first and second surfaces are substantially parallel.

11. The coated abrasive article of claim 1 , wherein the peripheral surface does not taper, and the first and second surfaces have substantially the same size.

12. The shaped ceramic abrasive particle of claim 1 comprising a thickness and a length, wherein the thickness is less than or equal to one-third of the length.

13. The shaped ceramic abrasive particle of claim 1 , wherein the peripheral surface comprises a plurality of walls connecting the substantially straight edges of the at least one inwardly extending region comprising two substantially straight edges.

14. The shaped ceramic abrasive particle of claim 1 , wherein the peripheral surface does not taper.

15. A coated abrasive article comprising a backing and an abrasive layer, wherein the abrasive layer comprises a plurality of abrasive particles secured to a major surface of the backing by a make layer and a size layer, wherein the plurality of abrasive particles comprises shaped ceramic abrasive particles each comprising:
a first surface having a generally triangular perimeter having three corners and at least two inwardly extending regions, wherein at least one inwardly extending region comprises two substantially straight edges, wherein each inwardly extending region terminates at two of the three corners of the perimeter, and wherein at least two of the three corners defines an acute interior angle in a range from 30 degrees to 50 degrees;
a second surface opposite, but not contacting, the first surface, wherein the second surface has substantially the same size and shape as the first surface and wherein the first and second surfaces are substantially parallel; and
a peripheral surface disposed between and connecting the first and second surfaces, wherein the peripheral surface comprises a plurality of walls connecting the substantially straight edges of the inwardly extending regions, and wherein the peripheral surface does not taper;
wherein at the inwardly extending regions have a maximum depth that is that is between 5 percent and 15 percent of a maximum dimension of the shaped ceramic abrasive particle parallel to the maximum depth;
wherein the shaped ceramic abrasive particles consist essentially of a ceramic material, wherein the ceramic material comprises alpha alumina.

16. The coated abrasive article of claim 15 , wherein the generally triangular perimeter comprises three inwardly extending regions, and wherein the three corners each define an acute interior angle in a range from 40 degrees to 50 degrees.

17. The coated abrasive article of claim 15 , wherein the plurality of abrasive particles comprises, on a numerical basis, at least 90 percent of the shaped ceramic abrasive particles, wherein the shaped ceramic abrasive particles are sized according to an abrasives industry recognized specified nominal grade.

18. The coated abrasive article of claim 17 , wherein the abrasive layer further comprises a supersize coat applied over the plurality of abrasive particles.

19. The coated abrasive article of claim 16 , wherein the plurality of abrasive particles comprises, on a numerical basis, at least 90 percent of the shaped ceramic abrasive particles, wherein the shaped ceramic abrasive particles are sized according to an abrasives industry recognized specified nominal grade.

20. The coated abrasive article of claim 19 , wherein the abrasive layer further comprises a supersize coat applied over the plurality of abrasive particles.

21. The coated abrasive article of claim 1 wherein at least two inwardly extending regions comprises two substantially straight edges.

22. The coated abrasive article of claim 2 wherein each inwardly extending region comprises two substantially straight edges.

23. The coated abrasive article of claim 15 wherein at least two inwardly extending regions comprises two substantially straight edges.

24. The coated abrasive article of claim 16 wherein each inwardly extending region comprises two substantially straight edges.

Assignees

• 3M Innovative Properties Company

Inventors

• Adefris Negus B

Classifications

• B24D3/14 Primary

  ceramic, i.e. vitrified bondings · CPC title

• B24D11/00

  Constructional features of flexible abrasive materials; Special features in the manufacture of such materials · CPC title

• C04B2235/94

  Products characterised by their shape · CPC title

• C04B2235/72

  Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics · CPC title

• C04B2235/602

  Making the green bodies or pre-forms by moulding · CPC title