Head for an oral care implement

1. A head for an oral care implement comprising:

a mounting surface, and

at least one tuft extending from the mounting surface,

the tuft comprising a first group of filaments and at least a second group of filaments, the first group of filaments being surrounded by the second group of filaments,

the filaments of the first group having a longitudinal axis and a cross-sectional area extending in a plane perpendicular to the longitudinal axis, and the cross sectional area having a substantially circular shape with a first diameter, and

the filaments of the second group having a longitudinal axis and a cross-sectional area extending in a plane perpendicular to the longitudinal axis, and the cross sectional area having a substantially circular shape with a second diameter,

wherein the first diameter is smaller than the second diameter and wherein the first diameter is about 0.15 mm to about 0.16 mm, and the second diameter is about 0.17 mm to about 0.18 mm.

2. The head of claim 1 , wherein the filaments of the first group have a first length and the filaments of the second group have a second length different from the first length, whereby there is a difference in length between the first length and the second length.

3. The head of claim 2 , wherein the first length is greater than the second length.

4. The head of claim 2 , wherein the difference in length is from about 1.1 mm to about 1.9 mm.

5. The head of claim 4 , wherein the difference in length is from about 1.3 mm to about 1.7 mm.

6. The head of claim 5 , wherein the difference in length is about 1.5 mm.

7. The head of claim 1 , wherein the tuft has a longitudinal axis and a cross-sectional area extending in a plane perpendicular to the longitudinal axis, and the cross sectional area has a substantially circular shape with a diameter of about 2.8 mm to about 3.2 mm.

8. The head of claim 1 , wherein the first group of filaments has a longitudinal axis and a cross-sectional area extending in a plane perpendicular to the longitudinal axis, and the cross sectional area of the first group of filaments has a substantially circular shape with a diameter of about 0.8 mm to about 1.2 mm.

9. The head of claim 1 , wherein at least some of the filaments of the first group and/or at least some of the filaments of the second group are tapered and have a pointed tip.

10. The head of claim 1 , wherein the tuft has a free end having a topography selected from the group consisting of a linear shape, a concave shape, a convex shape, a dome shape, or any combination thereof.

11. The head of claim 1 , wherein the filaments of the first group differ from the filaments of the second group in at least one characteristic selected from the group consisting of bending stiffness, cross-sectional shape, material, texture, color, and any combination thereof.

12. The head of claim 1 , wherein the at least one tuft is inclined relative to the mounting surface of the head at an angle (α) defined between the tuft and the mounting surface.

13. The head of claim 12 , wherein the angle (α) is from about 45° to about 89°.

14. The head of claim 13 , wherein the angle (α) is from about 70° to about 80°.

15. The head of claim 12 , wherein the at least one tuft is inclined in a direction that is substantially parallel to the longitudinal extension of the head.

16. The head of claim 12 , wherein the head comprises at least a first tuft inclined in a direction towards a distal end of the head and at least a second tuft inclined in a direction towards a proximal end of the head.

17. The head of claim 1 , wherein the tuft is attached to the head by a hot-tufting process.

18. The head of claim 1 , wherein the first diameter is about 0.152 mm.

19. The head of claim 1 , wherein the second diameter is about 0.178 mm (7 mil).

20. An oral care implement comprising the head of claim 1 .