JPH0354158B2 - - Google Patents

Abstract

Photobleach, such as zinc or aluminium phthalocyanine sulphonate is incorporated into detergent powder by spraying in solution or suspension. Reduced loss of photobleach during processing and during storage of the resultant powder is achieved by adopting the process.

Description

[Detailed description of the invention]

The present invention relates to a method for producing detergent powder containing photobleach. Photobleach is now being introduced into cleaning powders, especially those sold in the sunnier countries of Europe and South America. The most suitable method of incorporating photobleachs such as zinc phthalocyanine sulfonate or aluminum phthalocyanine sulfonate into detergent powders produced by spray drying is to incorporate these photobleachs with other ingredients such as detergent active compounds and builders. It will be mixed into the aqueous crutcher slurry.
However, when using this method in practice, a loss of photobleach occurs and the resulting powder has poor stability during storage. In accordance with the present invention, a method of manufacturing a powdered detergent fabric cleaning product in which a spray dried or granulated base powder is formed and the base powder is then combined with a photobleach compound, comprising: A method is provided, characterized in that the solution or suspension is combined by spraying onto a powder comprising a base powder. European Patent Publication No. 0057088 (Procter & Gamble Limited) discloses spraying an aqueous solution of photobleach and amorphous phosphate onto a mixture of storage-sensitive detergents and hydratable salts. There is. In contrast to this disclosure, the present invention provides a generally applicable method of incorporating photobleach into spray-dried or granulated powders without losses during processing or subsequent storage. One of the main properties of photobleach is its ability to adsorb onto the fibers of articles. This property is highly concentration dependent and sensitive to the deformation of the molecular structure that would occur when photobleach is incorporated into the clutcher slurry.
To compensate for the loss of the original photobleach, if you decide to process the powder by including the photobleach in the slurry, you will obtain the desired performance in the spray-dried product. Therefore, it may be necessary to increase the initial concentration. This would be a very expensive procedure. Even this measure would not compensate for losses that occur during storage if the photobleach is incorporated into the powder by the slurry manufacturing and spray drying routes. The photobleach is preferably zinc phthalocyanine sulfonate or aluminum phthalocyanine sulfonate and the photobleach is sprayed in a very dilute aqueous solution or suspension onto the spray dried or granulated base powder. It is preferable to Better control of the amount of photobleach incorporated into the powder may be obtained if this concentration is very dilute, e.g. 0.001
% to 0.2% by weight. This solution or suspension can be prepared in any desired manner;
Curtains in inclined pan granulators, fluidized bed or rotating drum mixers, such as Eirich pans, for example, or on powders on moving belts or as they fall from one level of the plant to another. can be sprayed onto powders that have been spray dried or granulated. This solution or suspension preferably contains inorganic acid salts such as sodium dihydrogen phosphate, sodium bicarbonate and sodium bisulfate which have been found to improve the physical properties of the atomized powder. The question of brightness or apparent whiteness actually applies only to the cleaning of fabrics; other indicators are suitable, for example in the field of dishwashing. Therefore, the present invention is only applicable to fabric cleaning products. However, as indicated above,
The present invention involves absorbing the liquid component of a spray-dried product or composition produced by thermal spray drying of an aqueous clutcher slurry onto a fixed component to provide a balanced free-flowing powdered solid. It can be applied to both granulated products manufactured by The main ingredients of the fabric cleaning product according to the invention are one or more anionic and/or nonionic surfactants and one or more detergency builders and a number of optical components. Representative anionic detersive active compounds that may be present in amounts of about 2% to 35% by weight of the finished composition include:
Sodium alkylbenzene sulfonates, preferably C ₁₀ to C ₁₆ alkyl compounds, sodium primary and secondary alkyl sulfates, preferably C ₁₀ to C ₂₂ alkyl sulfates, sodium olefin sulfonates, preferably C ₁₀ to C ₁₈ sulfonates and sodium alkanesulfonates. Soaps of fatty acids, preferably sodium and potassium salts of C ₁₀ to C ₂₂ fatty acids, both saturated and unsaturated, may also be present. If the soap is the only anionic surfactant, it may be present in an amount of about 65% by weight of the finished composition to about 0.2% if other anionic surfactants are present. Typical soaps that can be used are those formed from hydrogenated oils of natural oils containing a high proportion of oleic acid, such as coconut oil, tallow, hydrogenated tallow, hydrogenated rapeseed oil and sunflower oil. A typical nonionic surfactant is alcohol 1
Ethoxylated primary and secondary alcohols of 8 to 25 carbon atoms containing from 3 to 25 moles of ethylene oxide per mole. These materials generally weigh 1/2 based on the weight of the finished composition.
It may be present in an amount of % to 25% by weight. Typical detergency builders that can be used are water-soluble phosphates, carbonates and aluminosilicates, especially the sodium and potassium salts of these compounds. Organic builders such as sodium carboxymethyloxysuccinate, sodium citrate, sodium polyacrylate and sodium nitrilotriacetate may also be used. Any of these compounds, or any other builder compound, in any suitable mixture may be present in an amount of 5% by weight of the finished composition.
It may be used in an amount of up to 60% by weight. Other ingredients commonly present are bleaching agents and their precursors such as tetraacetyl ethylene diamine, corrosion inhibitors, anti-resoiling agents, fluorescent agents, stabilizers, enzymes and a substantial proportion of water. The method of the invention is illustrated in the examples below, with Example 1 being a comparative example. Example 1 Aluminum phthalocyanine sulfonate (AIPCS) was incorporated into a clutcher slurry having the following composition in the amounts shown in Table 1. This slurry was then spray dried to a powder and the content of AIPCS was determined by visible absorption spectroscopy. Weight% Sodium dodecylbenzenesulfonate 16.8 Sodium tripolyphosphate 17.5 Sodium silicate (ratio 2:1) 8.1 Sodium carboxymethylcellulose 0.6 Sodium sulfate 17.0 AIPCS Table 1 water and trace components 40.0 100.0

Table Example 2 A carefully measured amount of AIPCS having a concentration of 0.299% was injected into an Amicon™ with a Delavan Watson™ single fluid atomization jet at an operating pressure of 70 psig. was sprayed onto the spray-dried base powder from a pressure vessel. This base powder (20 Kg) was agitated by rotating in a 1 m pan granulator tilted at an angle of 50 to 54° to the horizontal and rotating at a speed of 22 rpm. The base powder formulation was: sodium dodecylbenzenesulfonate 25.0 sodium tripolyphosphate 26.0 sodium silicate 12.0 sodium carboxymethyl cellulose 1.0 sodium sulfate 25.0 water and trace ingredients 11.0 100.0 . The content of AIPCS was determined as described above and was found to be the same as the theoretical value within experimental error. Example 3 An aqueous solution containing AIPCS (0.08%) and sodium dihydrogen phosphate (25%) is transferred from an Amicon™ pressure vessel onto a falling curtain of spray-dried base powder having the composition shown in Example 2. was sprayed on. The powder flow rate was 25.1 Kg/min, and the AIPCS solution was sprayed at a flow rate of 1.6 Kg/min. The AIPCS content was determined as described above and was found to be the same as the theoretical value within experimental error.
That is, there was no measurable loss of AIPCS during processing. Examples 2 and 3 show the advantages obtained in terms of low losses of AIPCS during processing by implementing the method of the invention compared to the method specified in Example 1. Example 4 The storage stability of detergent powders produced by the method described in Examples 1, 2 and 3 was evaluated. These powders are sealed in non-laminated packs and then
Stored for 18 weeks at 30°C and 80% relative humidity. initially and at 6 week intervals,
The content of AIPCS was analyzed spectrophotometrically. The results are shown in Table 2.

It can be seen that the percentage loss of AIPCS is significantly lower when AIPCS is added to the powder by spraying as in Examples 2 and 3, rather than incorporating AIPCS into the clutcher slurry as in Example 1.

Claims (1)

Claims: 1. A method of manufacturing a powdered detergent fabric cleaning product comprising forming a spray-dried or granulated base powder and then combining the base powder with a photobleach compound, comprising: a dilute solution or suspension on the powder containing the base powder. 2. Claim 1, wherein the concentration of photobleach in the solution or suspension is 0.001 to 0.299% by weight.
The method described in section. 3. The method according to claim 1, wherein the photobleach is zinc phthalocyanine sulfonate or aluminum phthalocyanine sulfonate. 4. A method according to any of claims 1 to 3, wherein the solution or suspension also contains an inorganic acid salt. 5. The method of claim 4, wherein the inorganic salt comprises sodium dihydrogen phosphate, sodium bicarbonate or sodium bisulfate.