Polished talc microbeads

Abstract

Polished talc microbeads, i.e. polished talc particles with a largest average diameter of less than 500 μm and methods for the preparation thereof, which microbeads are especially suitable to be use as an alternative for plastic microbeads used in cosmetics and personal hygiene products. Body scrubs, tooth pastes and soaps comprising the present polished talc microbeads. The use of polished talc microbeads with a talc content of more than 70% (w/w) and a largest diameter of less than 500 μm as a substitute for plastic microbeads in cosmetics and personal hygiene products.

Claims

1. A liquid soap consisting of: (a) spherical and smooth talc microbeads in an amount of 1% to 5% (w/w); (b) surfactant; and (c) water; wherein the talc microbeads have a talc content of at least 75% (w/w); and the largest diameter of the talc microbeads is 500 μm or less.

2. The liquid soap of claim 1, wherein the largest diameter of the talc microbeads is between 250 μm and 500 μm.

3. The liquid soap of claim 1, wherein the largest diameter of the talc microbeads is between 125 μm and 250 μm.

4. The liquid soap of claim 1, wherein the largest diameter of the talc microbeads is between 0.5 μm and 125 μm.

5. The liquid soap of claim 1, wherein the amount of surfactant is between 1% and 15% (w/w).

6. A dry soap consisting of: (a) spherical and smooth talc microbeads in an amount of at least 50% (w/w); and (b) surfactant; wherein the talc microbeads have a talc content of at least 75% (w/w); and the largest diameter of the talc microbeads is 500 μm or less.

7. The dry soap of claim 6, wherein the largest diameter of the talc microbeads is between 250 μm and 500 μm.

8. The dry soap of claim 6, wherein the largest diameter of the talc microbeads is between 125 μm and 250 μm.

9. The dry soap of claim 6, wherein the largest diameter of the talc microbeads is between 0.5 μm and 125 μm.

10. The dry soap of claim 6, wherein the amount of surfactant is at least 15% (w/w).

Description

(1) The present invention will be further detailed in the following examples of preferred embodiments of the present invention. In the examples, reference is made to a FIG. 1 wherein:

(2) FIG. 1: shows a 30× magnification of the present polished talc microbeads after tumbling (right) and before tumbling (left).

EXAMPLES

Example 1: General Preparation of the Polished Talc Microbeads

(3) Coarse talc (hydrated magnesium silicate) of less than 10 cm diameter was subjected to crushing and subsequently sieved to obtain a fractions with 1) an average largest diameter of 500 to 250 μm; 2) an average largest diameter of 250 to 125 μm; 3) an average largest diameter of 125 to 90 μm and 4) an average largest diameter of less than 90 μm. Subsequently, the fractions were added into a rotating drum and allowed to tumble at 60 rpm for 20 minutes in order to polish the talc particles. A representative example of the 500 to 250 μm fraction before (left) and after (right) tumbling is shown in FIG. 1. As can be seen in FIG. 1, tumbling provides smoothness and roundness to the talc particles and, additionally, provides a more spherical shape.

Example 2: Powdered Soap (Dry Soap)

(4) Three formulations of a powdered (dry) soap were prepared by mixing the constituting ingredients in any given order:

(5) TABLE-US-00001 Fomulation 1 Amount in Compound percentage (w/w) Function Sodium lauryl sulfoacetate 26 Surfactant Polished talc ad 100 fraction less than 250 μm Sorbitol 5 Humectant Citric acid monohydrate 0.3 Buffer

(6) TABLE-US-00002 Formulation 2 Amount in Compound percentage (w/w) Function Sodium lauryl sarcosinate 24.7 Surfactant Polished talc ad 100 fraction less than 250 μm Citric acid 0.3 Buffer Sodium methyl cocoyl 5.2 Surfactant taurate

(7) TABLE-US-00003 Formulation 3 Amount in Compound percentage (w/w) Function Sodium lauryl sulfoacetate 23.0 Surfactant Polished talc ad 100 fraction less than 250 μm Citric acid 0.3 Buffer Sodium methyl cocoyl 5.7 Surfactant taurate Sorbitol 5.0 Humectant Allantoin 0.2 Skin soothing and protection Urea 0.3 Skin conditioning

Example 3: Liquid Soap

(8) TABLE-US-00004 Formulation liquid soap Amount in Compound percentage (w/w) Function Aqua Ad 100 Solvent Acrylates/C10-30 Alkyl 0.8 Viscosity modifier Acrylate Crosspolymer Sodium Lauroyl  5.13 Surfactant Sarcosinate Sodium Laureth Sulfate 2.7 Surfactant Cocamidopropyl Betaine 0.9 Surfactant Triethanolamine q.s. buffer Polished talc 2.5 fraction less than 250 μm
Manufacturing Procedure:

(9) Heat water of phase A up to 40° C. Add Acrylates/C10-30 Alkyl Acrylate Crosspolymer while stirring and homogenize for 1 to 2 min. to ensure complete hydration. Mix the remained of the ingredients and adjust the pH with triethanolamine to 6.8. Stir with moderate speed until a homogenous gel is obtained.

(10) Appearance: milky homogenous gel

(11) pH-Value: 6.8

(12) Viscosity (Brookfield RVDVI, spindle 3, speed 10 rpm) mPa.Math.s: 4500-7000

(13) Stability: more than 3 months.