COMPOSITIONS

Abstract

A composition comprising alkaline earth metal carbonate and phyllosilicate, use of a composition comprising alkaline earth metal carbonate and phyllosilicate as a filler in a paper product and a method of preparing a composition comprising alkaline earth metal carbonate and phyllosilicate.

Claims

1. A composition comprising alkaline earth metal carbonate and phyllosilicate, wherein the solids content of the composition comprises: at least about 45 wt % alkaline earth metal carbonate; and at least about 2 wt % phyllosilicate, and wherein the composition has a brightness between about 85 and about 95.

2. The composition of claim 1, wherein the solids content of the composition comprises from about 45 wt % to about 98 wt % alkaline earth metal carbonate.

3. The composition of claim 1, wherein the solids content of the composition comprises from about 2 wt % to about 55 wt % phyllosilicate.

4-15. (canceled)

16. The composition of claim 1, wherein the alkaline earth metal carbonate is calcium carbonate.

17-18. (canceled)

19. The composition of claim 1, wherein the phyllosilicate is kaolin.

20. The composition of claim 1, wherein the phyllosilicate is talc.

21-32. (canceled)

33. The composition of claim 1, wherein the composition comprises less than about 0.3% dispersant based on the total weight of the dry alkaline earth metal carbonate.

34-35. (canceled)

36. The composition of claim 1, wherein up to about 20 wt % of particles in the composition are larger than about 10 m.

37. The composition claim 1, wherein the composition demonstrates at least about 10% less abrasivity in comparison to a corresponding composition in accordance with claim 1 which does not comprise said phyllosilicate.

38. The composition of claim 1, wherein the composition demonstrates at least about 20% less abrasivity in comparison to a corresponding composition in accordance with claim 1 which does not comprise said phyllosilicate.

39-42. (canceled)

43. A composition comprising alkaline earth metal carbonate and phyllosilicate, wherein from about 45 wt % to about 85 wt % of particles in the composition are smaller than about 2 m, from about 15 wt % to about 30 wt % of particles in the composition are smaller than about 0.5 m, and up to about 20 wt % of particles in the composition are larger than about 10 m.

44. The composition of claim 43, wherein the alkaline earth metal carbonate is calcium carbonate.

45-46. (canceled)

47. The composition of claim 43, wherein the phyllosilicate is kaolin.

48. The composition of claim 43, wherein the phyllosilicate is talc.

49-76. (canceled)

77. The composition of claim 43, wherein the composition demonstrates at least about 10% less abrasivity in comparison to a corresponding composition in accordance with claim 43 which does not comprise said phyllosilicate.

78. The composition of claim 43, wherein the composition demonstrates at least about 20% less abrasivity in comparison to a corresponding composition in accordance with claim 43 which does not comprise said phyllosilicate.

79-125. (canceled)

126. A papermaking composition comprising the composition of claim 1.

127. (canceled)

128. A paper product prepared from the papermaking composition of claim 126.

129. A paper product comprising a filler, wherein the filler comprises the composition of claim 1.

130. A process for preparing the composition of claim 1 comprising: combining alkaline earth metal carbonate with phyllosilicate.

131. A process for making a paper product comprising: combining the composition of claim 1 with a fibrous pulp suitable for making a paper product to form a papermaking composition; and forming a paper product from the papermaking composition.

132. The process of claim 131, wherein the fibrous pulp comprises cellulose.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0126] Certain embodiments of the invention will now be described, by way of example only and without limitation, with reference to the following Figures and Examples, in which:

[0127] FIG. 1 shows the abrasivity of compositions of different types of ground calcium carbonate which comprise different amounts of talc or kaolin.

[0128] FIG. 2 shows the abrasivity of compositions of calcium carbonate which comprise different amounts of talc or kaolin.

EXAMPLES

[0129] Samples of ground calcium carbonate, kaolin and talc shown in Table 1 below were obtained from commercial sources.

TABLE-US-00001 TABLE 1 wt % particles wt % particles Brightness smaller than smaller than Sample (ISO) 5 m 2 m Talc A 80.7 31.6 8.5 Talc B 82.8 74.0 30.1 Talc C 86.8 68.8 32.8 Kaolin A 87.8 84.9 49.5 Kaolin B 81.8 89.1 57.7 GCC A 92.5 95.2 60.8 GCC B 93.3 98.3 74.0

[0130] Compositions comprising ground calcium carbonate (GCC) and either kaolin or talc were prepared by blending slurries of each component in the required ratio.

[0131] Abrasivity and brightness of these compositions was then determined by the methods described above in the detailed description of the invention.

Example 1

[0132] The brightness and particle size distribution of the compositions disclosed in Table 2 below was determined.

TABLE-US-00002 TABLE 2 % particles % particles % particles Brightness smaller than smaller than smaller than Composition (ISO) 5 m 2 m 0.5 m GCC B 93.3 98.3 74.0 25.1 GCC B + 5 92.9 96.6 72.3 24.3 wt % Talc A GCC B + 5 92.8 97.4 72.7 23.7 wt % Talc B GCC B + 10 92.7 97.4 72.0 23.6 wt % Kaolin A

[0133] It was surprisingly found that the brightness of the compositions comprising ground calcium carbonate and either talc or kaolin did not change considerably in comparison to ground calcium carbonate alone.

Example 2

[0134] Compositions comprising ground calcium carbonate and different amounts of talc or kaolin were prepared as described above. The abrasivity of these compositions was determined. The results are shown in FIGS. 1 and 2.

[0135] It was surprisingly found that addition of talc or kaolin to ground calcium carbonate reduced the abrasivity of the composition.