CN1296523A - Coloured granular composition for use in particulate detergent compositions - Google Patents

Abstract

A granular composition suitable for incorporation into a particulate detergent composition comprises: (a) a coloured or fluorescent ingredient, for example, a photobleach such as zinc or aluminium phthalocyanine sulphonate; (b) a carrier material for the coloured or fluorescent ingredient which is an alpha -hydroxy organic acid, preferably citric acid; (c) a water-soluble or water-dispersible barrier material, preferably a water-soluble starch or polyvinyl alcohol; and (d) an inorganic flow modifier, for example, silica and/or china clay. Preferably, the coloured or fluorescent ingredient is dispersed onto the alpha -hydroxyacid which is mixed with part or all of the inorganic flow modifier and the whole treated with the barrier material, then granulated with any remaining inorganic flow modifier. The granular material can be incorporated into particulate detergent compositions, where it shows a reduced tendency to leave stains on washed fabrics.

Description

Colored granular composition for use in granular detergent compositions

field of invention

The present invention relates to rapidly dissolving, low-staining granular compositions containing macroscopically clear, eg, pigmented or fluorescent components, such as photobleaches. The present invention more particularly relates to particles containing colored or fluorescent components which can be incorporated into detergent compositions without encountering the problem of fabric staining during laundering.

Background and prior art

The use of colored particles in detergent formulations provides a clear appearance to the product as well as providing functional benefits. During laundering, it is undesirable for these colored particles to deposit on the surface of the fabric and cause the fabric to stain. It was also noted that these stains could not be washed out in subsequent washes. Additionally, the uneven concentration of these speckles on the substrate can lead to localized high concentrations of active, causing fabric damage.

US4097418 (Procter & Gamble, 1978) discloses a kind of coloring grain that does not have dyeing property, and it comprises the agglomerate of granular water-soluble inorganic alkali salt and anionic surfactant, and it contains dyestuff or pigment. Mixing the dye and the anionic surfactant prior to agglomeration inhibits the pigment particles from adhering to each other and to the surface of the fabric, thereby inhibiting fabric dyeing.

US4762636 (Ciba-Geigy, 1988) discloses a method for obtaining particles of defined physical properties floating on aqueous treatment solutions, which release active ingredients without depositing on the substrate.

Summary of the invention

It is therefore an object of the present invention to provide a granular composition containing a coloring or fluorescent component which can be incorporated into detergent compositions without encountering the problem of fabric staining during washing.

It is also an object of the present invention to provide granular compositions having excellent non-staining properties which can be prepared more economically and with lower investment costs than known methods.

Accordingly, the present invention provides granular compositions suitable for incorporation into granular detergent compositions comprising:

(a) a coloring or fluorescent component,

(b) alpha-hydroxy organic acids as carrier materials for colored or fluorescent components,

(c) water-soluble or water-dispersible barrier materials, and

(d) Inorganic flow improvers.

The water soluble or water dispersible barrier material provides a protective layer or coating over the mixture of the pigmented or fluorescent component and its carrier material a-hydroxy organic acid. Preferably at least part of the inorganic flow improver is so protected. Other inorganic flow improvers that are not protected by the barrier material may also be present.

The term coating as used above does not necessarily mean complete coating.

Therefore, according to a preferred embodiment of the present invention,

- the coloring or fluorescent component is dispersed or coated on the a-hydroxy organic acid in the form of a coating agent,

- a-hydroxy organic acids loaded with coloring or fluorescent components are mixed with flow improvers or parts thereof,

- The barrier material is in the form of a coating agent coated on said a-hydroxy organic acid and flow improver mixture, which is mixed (in admixture) with any remainder of the flow improver.

According to another preferred aspect of the present invention, the granular composition comprises:

- 40% - 90% by weight, preferably 60% - 80% by weight of a-hydroxy organic acids,

- 0.5% - 5% by weight, preferably 1% - 2% by weight of colored or fluorescent components,

- 10%-50% by weight, preferably 18%-40% by weight of inorganic flow improvers, and

- 0.5% to 5% by weight, preferably 1% to 3% by weight of water-soluble barrier material.

The granular compositions of the present invention can be prepared by a method in which the coloring or fluorescent component is dispersed in an a-hydroxy acid, mixed with some or all of the inorganic flow improver and treated entirely with a barrier material, and then treated with the remaining inorganic flow improver. Flow improver granulation.

Therefore according to another aspect of the present invention, there is provided a method for preparing a granular composition comprising the steps of:

(i) dispersing the coloring or fluorescent component onto the alpha-hydroxy acid and granulating with an inorganic flow improver or part of an inorganic flow improver;

(ii) drying the material preferably at 15-50°C, more preferably at 20-40°C;

(iii) treating the dry material with a water-soluble or water-dispersible barrier material;

(iv) Optionally, granulate the treated material with remaining flow aid and dry.

The a-hydroxy organic acid may be selected from citric acid, adipic acid, tartaric acid, maleic acid and others. A particularly preferred acid is citric acid.

Examples of coloring or fluorescent components are photosensitizers (also known as photobleaches), especially phthalocyanine dyes; coloring dyes and pigments; optical brighteners; and mixtures thereof. Particularly preferred ingredients are photobleach, zinc phthalocyanine sulfonate and aluminum.

Inorganic flow improvers may be selected from china clay, (preferably washed china clay), silica, precipitated silica, precipitated calcium carbonate and diatomaceous earth/silica. China clay, silica and mixtures thereof are particularly preferred.

The water-soluble or water-dispersible, preferably water-soluble barrier material may be suitably selected from water-soluble starch, polyvinyl alcohol, polyethylene glycol and latex. Preferred materials are starch and polyvinyl alcohol.

As noted above, the granules of the invention are prepared by dispersing the pigmented or fluorescent component onto the a-hydroxy acid in, for example, a rotating pan granulator, followed by or simultaneously with the addition of a suitable flow improver. The resulting agglomerates are dried and further coated with a water soluble or water dispersible barrier material, optionally further pelletized with a flow improver and dried.

Another subject of the present invention is a granular detergent composition comprising an organic detergent surfactant and other detergent ingredients and comprising a granular composition as defined above. The granular laundry detergent compositions of the present invention suitably comprise from 5% to 60% by weight of organic surfactant, from 10% to 80% by weight of detergency builder, from 0.1% to 10%, preferably from 0.5% to 5% by weight of the particulate combination as defined above matter, and optionally other detergent ingredients to 100% by weight.

The invention is now further illustrated by the following non-limiting examples, in which parts and percentages are by weight unless otherwise indicated. Examples indicated by numbers are according to the present invention, and examples indicated by letters are comparative examples.

Example 1, Comparative Examples A-C Formulations of Granular Compositions

Example 1: Photobleach Granules Using Citric Acid Carrier and Starch Barrier Material

8Kg citric acid is dropped in the rotary disc granulator, sprays 200g aluminum phthalocyanine sulfonate solution (10% concentration) on it. During spraying, half the amount of the mixture of 0.8 Kg china clay and 500 g silica was added. The material was dried at 40°C for about 4 hours. The material was returned to the rotary pan granulator and 500 g of starch solution (10% strength by weight) was sprayed. Add the remaining half of the china clay and silica mixture. The material was dried at 40°C for 4 hours.

The formulation of the particulate matter is as follows: Raw material (g) Final Formulation (wt%) Aluminum phthalocyanine sulfonate 20 2 citric acid 8000 80 porcelain clay 800 8 silica 500 5 starch 50 0.5 water to 100% 630 4.5

Example 2: Photobleach particles using citric acid carrier and polyvinyl alcohol barrier material

Photobleach granules were prepared as in Example 1, but the starch solution was replaced by a polyvinyl alcohol solution (concentration 10% by weight).

The final formulation of the particulate matter was as follows: Raw material (g) Final Formulation (wt%) Aluminum phthalocyanine sulfonate 20 2 citric acid 8000 80 porcelain clay 800 8 silica 500 5 polyvinyl alcohol 50 0.5 water to 100% 630 4.5

Comparative Example A

Granules were prepared as in Example 1, but using baking soda instead of citric acid.

Comparative Example B

Granules were prepared as in Example 1, but using sodium tripolyphosphate instead of citric acid.

cleaning method

Cotton fabric pieces measuring 10 feet by 10 feet (25.4 cm by 25.4 cm) were placed in trays, each combined with 2 kg of water and one of the following photobleach granule compositions:

Example 1

Comparative Example A

Comparative Example B

Comparative Example C: Commercially available blue colored pellets, Laundrosil (trademark) PRT-2 from Sud-Chemie, containing aluminum phthalocyanine sulfonate supported on a bentonite support.

Allow each fabric piece to soak for 30 minutes. Afterwards, the fabric is washed in running water and dried in the sun. Each treatment was repeated four times. A panel of trained members visually analyzed fabrics for blue staining on a scale of 0-5 as follows:

grade degree of dyeing

0-1 minimum/can be ignored

2-3 can be felt

4-5 Obvious blue spots

The data were analyzed statistically and are presented in the table below. Example Carrier material in photobleach granules average grade 1 citric acid 0.9 A baking soda 2.9 B sodium tripolyphosphate 4.8 C commercial sale 4.5 CD@99% 0.71

The data in the table show that the commercially available granules stain the fabrics to a great extent, while the use of the granules according to the present invention has a clearly superior effect in controlling the dyeing of the fabrics. This is further evidenced by the fact that granules prepared in the same manner, but with baking soda or sodium tripolyphosphate instead of citric acid, did not inhibit significant fabric staining.

Examples 3 and 4: Detergent compositions

Granular detergent compositions were prepared by dry blending the following formulations:

Linear alkylbenzene sulfonate 30

Sodium carbonate 20

Sodium tripolyphosphate 40

Photobleach Granules (see below) 2

Enzymes, spices, fluorescent agents, water, etc. up to 100

The detergent composition of Example 3 contains the photobleach granules of Example 1 (citric acid carrier, starch barrier material).

The detergent composition of Example 4 contains the photobleach granules of Example 2 (citric acid carrier, polyvinyl alcohol barrier material).

Both detergent compositions are stored in 500g bags from May to December under the following conditions representative of summer, rainy and winter seasons in India: temperature(℃) Relative humidity(%) room temperature 35 80 hot and dry 42 45 hot and humid 42 85 No instability was detected at the end of the storage period as determined by visual inspection.

Claims (14)

1. A granular composition suitable for incorporation into granular detergent compositions comprising: (a) a coloring or fluorescent component, (b) carrier materials for colored or fluorescent components, It is characterized in that the carrier material (b) is an a-hydroxy organic acid, and the granular composition also comprises: (c) water-soluble or water-dispersible barrier materials, and (d) Inorganic flow improvers. 2. Granular composition as claimed in claim 1, characterized in that: - the coloring or fluorescent component (a) is dispersed or coated on the a-hydroxy acid (b) in the form of a coating agent, It is admixture with inorganic flow improver (d) or part thereof, and - The barrier material (c) is in the form of a coating applied to a mixture of a-hydroxy acid and inorganic flow improver which has been applied with the remaining inorganic flow improver (d) mix. 3. A granular composition according to any preceding claim, characterized in that it comprises: (a) 0.5%-5% by weight, preferably 1%-2% by weight of coloring or fluorescent components, (b) 40%-90% by weight, preferably 60%-80% by weight of a-hydroxy organic acids, (c) 0.5% to 5% by weight, preferably 1% to 3% by weight of a water-soluble or water-dispersible barrier material, (d) 10% to 50% by weight, preferably 18% to 40% by weight of inorganic flow improvers. 4. A granular composition according to any preceding claim, characterized in that the coloring or fluorescent component (a) is selected from photosensitizers (photobleaches), pigments, dyes and optical brighteners. 5. Granular composition according to claim 4, characterized in that the coloring or fluorescent component (a) is zinc or aluminum phthalocyanine sulfonate. 6. A granular composition according to any preceding claim, characterized in that the a-hydroxy acid (b) is selected from citric acid, adipic acid, maleic acid and tartaric acid. 7. Granular composition according to claim 6, characterized in that the a-hydroxy acid (b) is citric acid. 8. A granular composition according to any preceding claim, characterized in that the water soluble or water dispersible barrier material (c) is selected from water soluble starch, polyvinyl alcohol, polyethylene glycol and latex. 9. Granular composition according to claim 8, characterized in that the barrier material (c) is water-soluble and is starch or polyvinyl alcohol. 10. A granular composition according to any preceding claim, characterized in that the inorganic flow improver (c) is selected from china clay, silica, precipitated silica, precipitated calcium carbonate and diatomaceous earth or silica. 11. A granular composition as claimed in claim 10, characterized in that the inorganic flow improver (c) comprises china clay, silica or mixtures thereof. 12. A granular laundry detergent composition comprising from 5% to 60% by weight of organic surfactant, from 10% to 80% by weight of detergency builder and optionally other detergent ingredients to 100% by weight, characterized in that it comprises 0.1%-10% by weight, preferably 0.5%-5% by weight of the granular composition as claimed in any one of claims 1-11. 13. A method for preparing the granular composition as claimed in claim 1, characterized in that it comprises the steps of: (i) disperse the colored or fluorescent component (a) onto the a-hydroxy acid (b) and granulate with part or all of the inorganic flow improver (d); (ii) drying the particulate matter thus obtained; (iii) treating the dry material with a water-soluble or water-dispersible barrier material (c); (iv) Optionally, the thus obtained treated substance is granulated with the remaining inorganic flow improver (d) and dried. 14. The method according to claim 13, characterized in that the drying step (iii) is carried out at 15-50°C, preferably 20-40°C.