JPH04227700A - High bulk density granulated detergent composition and method for preparation thereof - Google Patents

Abstract

PURPOSE: To provide a granular detergent composition having a high bulk density and a good distribution characteristics.

CONSTITUTION: A granular detergent composition having a bulk density of at least 600 g/l, comprising 10-70 wt.% of a builder, at least 50 wt.% of the builder being a non-phosphate material, and 5-45 wt.% of a ternary active system comprising one or more nonionic surfactants, anionic surfactants and soap, wherein the weight ratio of the anionic surfactant to the nonionic surfactant is less than 5:1 and the amount of soap is 10-90 wt.% of the active system, and a process for preparation thereof.

COPYRIGHT: (C)1992,JPO

Description

[Detailed description of the invention]

FIELD OF INDUSTRIAL APPLICATION The present invention has a high bulk density and good dispensing properties.
s). Furthermore, the invention relates to a method for producing such a detergent composition, and in particular to a continuous method for its production.

BACKGROUND AND PRIOR ART There has recently been considerable interest within the detergent industry in powdered detergents with relatively high bulk densities, eg, 600 g/l and above. Several methods are known in the art by which densified powder detergents may be manufactured. Pillar tower treatment (p
Particular attention has been paid to densification of spray-dried powders by ost-tower treatment. For example, in the method disclosed in Japanese Patent Application Publication No. 61-069897 (Kao), a spray-dried detergent powder containing high levels of anionic surfactants and low levels of builders (zeolites) is mixed in a high-speed mixer. /Sequentially pulverize and granulate in a granulator. This granulation is carried out in the presence of a "surface property modifier" and optionally a binder. In this high-speed mixer/granulator, the spray-dried powder is first crushed into a divided fine state, then the surface modifier and optional binder are added, and the crushed material is granulated. A high bulk density final product is formed. Surface modifiers, which are finely divided particulates such as finely divided sodium aluminosilicate, are clearly necessary to prevent the desired composition from forming into large balls or cakes. The method described in this Japanese patent application is essentially a batch method and is therefore not very suitable for mass production of powdered detergents. British Patent Application Publication No. 1,517,713 (
UNILEVER discloses a process for densifying and spheronizing spray-dried or granulated powder detergents containing sodium tripolyphosphate and sodium sulfate with a "Marmerizer". The apparatus has a substantially horizontal, rough-surfaced rotary table located at the base within a substantially vertical, smooth-walled cylinder. British Patent Application Publication No. 1,453
, 697 (UNILEVER) discloses the use of a "Marmerizer™" to granulate powdered detergent ingredients together in the presence of a liquid binder to produce a granular detergent formulation. A disadvantage of this device is that powders or granules are produced which have a rather wide particle size distribution and in particular contain a relatively high proportion of oversized particles. Such materials exhibit poor dissolution and dispersion properties, especially in low temperature short time machine washing in Japanese and other Far Eastern washing machines. This is visible to consumers as deposits on the laundry, and results in a lot of waste in machine washing. European Patent Application No. 327,963 (HENKEL) consists of a substantially horizontal stationary hollow cylinder and its central rotating shaft, on which are mounted several different types of blades. A continuous process is disclosed for increasing the bulk density of spray-dried powder detergents by processing in a mixing device with. Example 1 consists of an anionic surfactant, a nonionic surfactant, and a soap, where the amount of soap is approximately 1 part of the active system.
Bulk density 595g containing 3% ternary active system
/l densified powder detergent is disclosed. The formulation also contains a builder system consisting of 10% zeolite and 20% sodium tripolyphosphate. It is believed that the latter sodium tripolyphosphate is responsible for the desired desired distribution properties in this composition. Related European Patent Application No. 337,330 (HENKEL) discloses a modification of the conventional method of spraying a liquid non-ionic surfactant onto a spray-dried base powder. The base powder is a low phosphate base powder and contains conventional ingredients in conventional amounts. The increase in bulk density by this method is at most 100 g/l as described in European Patent Application No. 220,024 (Procter
& Gamble), a spray-dried powder detergent containing high levels (30-85% by weight) of anionic surfactants is combined with an inorganic builder (sodium tripolyphosphate or sodium aluminosilicate and sodium carbonate). Mix and roll compactor ("chill sonator"
Compact under high pressure using a "chilsonator"). After removing oversized and undersized materials, it is granulated using conventional equipment, such as a fluidized bed tumble mixer, or a rotating drum or pan. Although powdered detergents with increased bulk density can be prepared by the above method,
All of the resulting powders have the disadvantage that they are more difficult to dispense in European automatic washing machines than the corresponding non-densified powders. As a result, a high proportion of the powder loaded into the machine remains in the dispenser, causing powder wastage and clogging. This problem is particularly acute when powdered detergents containing little or no tripolyphosphate are used at low temperatures. Because known densified powder detergents have poor dispensing properties, these detergents must be used in conjunction with dispensing devices or shuttles. This limits the ways in which the product can be used, which is not always well-understood by consumers, and shuttles, which are usually made of plastic, can contribute to the disposable problem. Therefore, the object of the invention is to provide at least 6
It is an object of the present invention to provide a high bulk density granular detergent composition or a component thereof having a bulk density of 00 g/l, preferably at least 650 g/l, and nevertheless having good distribution properties. Another object of the invention is to provide a process for obtaining such compositions. The method is particularly suitable for mass production of such compositions, and therefore a continuous process is preferred. Low phosphate content and at least 600g/l
It has been found that granular detergent compositions having a bulk density of , and also surprisingly good distribution properties, are obtained if certain requirements regarding the formulation are met.

DEFINITION OF THE INVENTION In a first aspect, the invention provides a granular detergent composition or a component thereof having a bulk density of at least 600 g/l, wherein at least 50% by weight is non-phosphate material. 70% by weight and one or more nonionic surfactants, anionic surfactants and soaps, the weight ratio of anionic surfactants to nonionic surfactants being less than 5:1, and soaps. The amount of active system is 10
and 90% by weight of a ternary active system. In a second aspect, the present invention provides for preparing particulate starting materials (i) in a high speed mixer/densifier with an average residence time of about 5 to 30 seconds, and then (ii) in a drying and/or cooling device. , a method of manufacturing a granular detergent composition or component of the present invention is provided. Preferably, the particulate starting material is brought into or maintained in a deformable state in the first stage.

DETAILED DESCRIPTION OF THE INVENTION The granular detergent composition of the present invention comprises:
Includes 10-70% by weight builder system and 5-45% by weight active system. The builder system of the compositions of the invention may be a single detergent builder in an amount of 10 to 70% by weight of the total formulation, or it may be a mixture of one or more detergent builders. However, the invention is particularly applicable to powder detergents in which at least 50% by weight of the builder system is non-phosphate material. This is because the distribution properties of the densified powders of conventional formulations are particularly poor. The builder can be any substance capable of reducing the level of free calcium ions in the wash liquor, preferably producing an alkaline pH, suspending soils to be removed from textiles, suspending textile softening clay materials. Compositions with other beneficial properties such as cloudiness are obtained. The level of detergent builder is preferably 15-60% by weight. Examples of suitable detergent builders that may be used in the present invention include precipitation builders such as alkali metal carbonates, bicarbonates, orthophosphates, sequestrant builders such as alkali metal tripolyphosphates or nitrilotriacetates. or ion exchange builders such as alkali metal aluminosilicates or zeolites, or layered silicates, e.g. Na-S
KS-6 (Hoechst) is mentioned. Preferably the detergent builder is a non-phosphate builder such as a zeolite. The active system of the composition of the invention is a ternary detergent active system consisting of an anionic surfactant, a nonionic surfactant, and a soap. It is present in an amount of 5-45% by weight of the total formulation. It has been found essential that the weight ratio of anionic surfactant to nonionic surfactant is less than 5:1, preferably less than 4:1. Furthermore, in order to obtain the desired good distribution properties, the amount of soap should be at least 10% and less than 90% by weight of the active system. Preferably the amount of soap is 10-60% by weight of the active system. Ternary active system anionic surfactants are typically water-soluble alkali metal salts of organic phosphoric and sulfonic acids having alkyl groups containing from about 8 to about 22 carbon atoms, where the term alkyl , including the alkyl moiety of a higher acyl group. Examples of suitable synthetic anionic detergent compounds include alkyl sulphates of sodium and potassium, for example produced from tallow or coconut oil, especially those obtained by sulphating higher (C8-C18) alcohols; alkyl (C9-C20) benzenesulfonates, especially sodium linear secondary alkyl (C10-C15) benzenesulfonates; and sodium alkyl glyceryl ether sulfates, especially ethers of higher alcohols obtained from tallow or coconut oil; Examples include ethers of synthetic alcohols obtained from petroleum. Preferred anionic detergent compounds are:
Sodium (C11-C15) alkylbenzene sulfonate and sodium (C16-C18) alkyl sulfate. Suitable nonionic detergent compounds which can be used in three-component active systems include, in particular, reaction products of compounds having hydrophobic groups and reactive hydrogen atoms, such as aliphatic alcohols,
Mention may be made of the reaction products of acids, amides or alkylphenols with alkylene oxides (in particular ethylene oxide alone or in mixtures with propylene oxide). Particular nonionic detergent compounds include alkyl (C6-C22) phenol-ethylene oxide (generally 3-25 EO, i.e. 3-25 units of ethylene oxide per mole) condensates, and aliphatic (C8-C18) phenol-ethylene oxide condensates. There is a condensation product of one or a second straight or branched chain alcohol and ethylene oxide, generally with an average of 3 to 40 EO. Alkoxylated fatty alcohols, especially ethoxylated alcohols, are preferred nonionic surfactants. The soaps used in the compositions of the invention are sodium salts of natural or synthetic fatty acids. The alkyl group of the fatty acid may be a branched or straight chain alkyl group containing 8 to 22, preferably 12 to 20 carbon atoms. A particularly preferred three-component active system is a sodium salt of an alkylbenzenesulfonic acid, an ethoxylated alcohol, and a
It is a mixture of sodium soaps having 2 to 20 carbon atoms. Although minimal amounts of amphoteric or zwitterionic detergent compounds may be used in the compositions of the present invention, this is generally undesirable due to its relatively high cost. The powder detergent of the present invention may contain any ingredients conventionally present in compositions for washing textiles. Optionally, the powder of the invention may contain sodium silicate. The high level of silicates in the composition has a beneficial effect on distribution and prevention of powder structure and washer corrosion, but the aluminosilicate Undesirable in powders containing salt. The invention is therefore particularly applicable to powders containing less than 5% by weight, especially less than 2% by weight, of sodium silicate, which would be expected to exhibit poor distribution properties. The granular detergent compositions or ingredients of the present invention may be used on their own as powder detergents, but with the addition of other ingredients,
It may also be used as a base powder for formulating complete textile cleaning powders. Examples of such ingredients include inorganic salts such as sodium carbonate, sodium silicate, etc., bleaching agents,
Included are fluorescent agents, suds suppressants, oxygen and fragrances. The final material typically contains 50-95% by weight of the above base powder.
contains. Adding more dense materials such as perborates and/or small particle size materials increases the bulk density value to 700
g/l or more. The granular detergent compositions or ingredients of the invention can be prepared by any method (batch or continuous) suitable for producing detergent compositions with an increased bulk density of 600 g/l or more. In a preferred method, the granular starting material is processed (i) in a high speed mixer/densifier with an average residence time of about 5-30 seconds and then (ii) in a drying and/or cooling device. In the first step of this process, the particulate starting materials are thoroughly mixed in a high speed mixer/densifier for a fairly short period of time, about 5-30 seconds. Particulate starting materials may be prepared by any suitable method, such as spray drying or dry mixing. The method is therefore very flexible with respect to the chemical composition of the starting materials. Phosphate-containing as well as zeolite-containing compositions and compositions with low or high active ingredient content may be used. The method is also suitable for densifying calcite/carbonate-containing detergent compositions. When using a spray-dried powder as particulate starting material, its particle porosity is high and the bulk density can be significantly increased by the method of the invention. It has been found that in order to obtain optimal densification it is important to subject the particulate starting material to a two-step densification process. The first step is
It is carried out in a high speed mixer/densifier, preferably under conditions in which the starting materials are rendered or maintained in a deformable state as described below. As a high speed mixer/densifier, Loedige(TM) CB 30 or CB
It is advantageous to use a 100 Recycler. These devices essentially consist of a large stationary hollow cylinder with a central rotating shaft. Several different types of blades are attached to this shaft. The axis varies from 100 to 2, depending on the degree of densification and desired particle size.
It can rotate at 500 rpm. The blades on the shaft provide sufficient mixing action for the solids and liquids that can be mixed at this stage. The average residence time depends somewhat on the rotational speed of the shaft, the position of the blade, and the exit weir (resistance). It is also possible to add solid materials into the Loedige recirculator. Other types of high speed mixers/densifiers with similar efficacy on powdered detergents are also contemplated. For example, Shugi(TM) G
ranulator or Drais(TM) K-TTP
80 can be used. It is clear that for use, handling and storage the detergent powder must no longer be in a deformable state. Therefore, the final processing step of the present invention is to dry and/or cool the densified powder. This step is carried out by known methods, for example in a fluidized bed apparatus (drying) or in an air lift (cooling). From a processing point of view, it is advantageous if the powder requires only a cooling step. This is because the required equipment is relatively simple in that case. The detergent material after the first step of the process according to the invention still has a considerable porosity, which allows the bulk density to be further increased. It has been found to be particularly advantageous to subject the powder to a further densification step, instead of choosing a long residence time in the high speed mixer/densifier to further increase the bulk density. In that case, the process is the same as that described in the applicant's co-pending unpublished European Patent Application No. 367,339. In this further processing step, the detergent material is preferably heated in a medium speed granulator/densifier for 1 to 10 minutes under conditions such that the powder is rendered or maintained in a deformable state. Process for 2-5 minutes. As a result, the particle porosity is further reduced. The main difference with the first step is the lower mixing speed and longer residence time of 1-10 minutes. This further processing step is carried out using Loedige Pl
It can be successfully carried out in a Loedige KM 300 mixer, also called oughshare. This device essentially consists of a hollow stationary cylinder with a rotating axis in the center, on which various plowshare blades are mounted. This axis is 40-16
It can rotate at a speed of 0 rpm. In some cases, one or more high speed cutters can be used to prevent excessive agglomeration. Another machine suitable for this process is, for example, the Drais(TM) K-T 160. In some cases, the applicant's co-pending European Patent Application No. 390
Small amounts of finely powdered solids, such as zeolites, can be added into the high speed mixer/densifier and/or the medium speed granulator/densifier, as disclosed in US Pat. Preferable for the first step, and essential for subsequent further processing steps, is the deformable state that the detergent powder should assume in order to obtain optimal densification.
state). This deformable state can be induced in a variety of ways, for example by operating at temperatures above 45°C. If a liquid such as water or a non-ionic substance is added to the particulate starting material, lower temperatures may be used, for example 35° C. or higher. According to a preferred embodiment of the invention, the spray-dried base powder leaving the tower at a temperature of 45° C. or higher is fed directly to the process of the invention. Alternatively, the spray-dried powder is first cooled, for example in an airlift, and then heated again after transport. Heat is applied externally but can be supplemented with internally generated heat, such as the heat of hydration of anhydrous sodium tripolyphosphate. The deformability of a powdered detergent can be derived from its compressive modulus, which can be derived from its stress-strain properties. To determine the compression modulus of a particular composition, a sample of the composition is compressed to form airless pellets with a diameter and height of 13 mm. Stress-strain curves during unconfined compression are recorded using an Instron testing machine at a constant strain rate of 10 mm/min. The compression modulus can be derived from the slope of the stress-relative strain curve during the first stage of the compression process, which reflects the elastic deformation. Compression modulus is expressed in MPa (mega pascals). To measure compression modulus at various temperatures, the Instron instrument can be equipped with a heatable sample holder. It has been found that the compressive modulus measured by the method described above correlates well with particle porosity reduction and associated bulk density increase under comparable processing conditions. This will be explained in more detail in Examples below. As a general rule, the powder has a compression modulus of less than about 25 MPa, preferably 20 MPa, as described above.
It is considered to be in a deformable state if it is less than . More preferably, the compression modulus is less than 15 MPa,
Particularly preferred are values below 10 MPa. The deformability of powders depends, among other conditions, on chemical composition, temperature and moisture content. In terms of chemical composition, the ratio of liquid to solid;
and the amount of polymer was found to be an important factor. Furthermore, it has generally been more difficult to render phosphate-containing powders into a deformable state than with zeolite-containing powders. The storage stability of the final detergent powder was determined by the Unrestricted Compressibility Test (Unc
onfined Compressibility
It can be evaluated by the average of Test). In this test, the detergent powder is placed in a cylinder with a diameter of 13 cm and a height of 15 cm, then a 10 kg load is applied to the powder (on top of the cylinder) and after 5 minutes the weight is removed and the walls of the cylinder are removed. Next, a load is applied to the top of the compressed powder detergent column, and the weight (kg) when the column collapses is measured as the load is increased. This value is a function of the viscosity of the detergent powder and was found to be a good measure of storage stability. dispensing performance
ce) is evaluated using the following method. Dry powder (100g
) into the dry dispenser tray (shower type dispenser) of a Philips AWB 126/l27 front-load automatic washing machine. Tap water with a flow rate of 5 l/min supplied at a pressure of 0.5 bar,
Pass through dispenser for 1 minute. Water temperature is 10-20
It is ℃. The remaining undistributed powder was taken out and heated at 100°C for 12
Let dry for a while and weigh. Dispensing residue is the residual dry powder expressed as a percentage of the original sample. 4
The average of the two measurements is taken as the final result.

EXAMPLES The present invention will be further explained by the following examples, but the present invention is not limited thereto. Unless otherwise specified, parts and percentages herein are by weight. In the examples, the following abbreviations are used: LAS: C12-C15 linear alkylbenzene sulfonate non-ionic: ethoxylated C12-C15
Fatty alcohol based nonionic surfactant Soap: Sodium salt of C15-C20 fatty acids Zeolite: Zeolite 4A (Wessalith [trademark], De
sold by Gussa) carbonate: sodium carbonate sulfate: sodium sulfate silicate: alkaline sodium silicate; Na2O:SiO
2 ratio = 1:2 Polymer: Copolymer of maleic acid and acrylic acid, molecular weight 70,000; CP5, sold by BASF Foam suppressant: Silicone oil Foam suppressing granules Examples 1-6 Spray-drying the aqueous slurry A powder detergent corresponding to the composition shown in Table 1 was prepared. Examples 1-3 relate to materials produced within the scope of the present invention. Examples 4 and 5 are comparative examples. Amounts are parts by weight.

Table 1 Powder was produced at 0.5-1.0 t/h in a pilot plant or at 20-30 t/h at full scale. The temperature at the bottom of the tower is approximately 60-70℃
Met. The physical properties of the spray dried powder are shown in Table 2.

[Table 2] The powder was processed using the Loedige Recycle as detailed above.
er CB fed directly into the continuous high speed mixer/densifier. CB 30 unit is for low throughput, C
B100 was used for high throughput. The unit is usually 1
Mixer tip speeds of 8 to 30 meters per second were operated. The comparative powder of Example 5 was processed in a conventional rotating drum mixer. The residence time was approximately 1-2 minutes in this case. Various solids and/or liquids and/or binders were added to the Recycler and drum as shown in Table 3. The properties of the powder after processing in the Loedige Recycler or rotating drum are also shown in Table 3.

Table 3 The powder may optionally be further passed through a medium speed granulator/densifier. This was carried out using the powder of Example 3. Table 4 shows the properties obtained as a result.

Table 4 A cooling/drying step was carried out in a fluidized bed to produce the final base powder. This resulted in a base powder having the properties shown in Table 5.

Table 5 Finally, the base powder was supplemented with bleach, enzymes, anti-foam granules (optionally containing silicone oil), perfume, etc. Details of added ingredients, final powder properties, and dispensing performance are shown in Table 6.

Table 6 The good distribution properties of the compositions of the invention are evident by comparing Examples 1-3 with Example 4. Example 4, which falls outside the required detergent activity specifications because the soap content of the active system is too low, exhibits poor distribution properties. The advantages of the method of the invention are clearly illustrated by a comparison of Examples 1-3 and Example 5. The powder of Example 5 was produced in a conventional drum without a densification step and has a bulk density of only 595 g/l.

Claims (13)

[Claims] 1. A granular detergent composition or ingredient having a bulk density of at least 600 g/l, comprising at least 5
a ternary active agent system consisting of 10 to 70% by weight of a builder, 0% by weight of which is a non-phosphate material, and one or more nonionic surfactants, anionic surfactants and soaps;
The weight ratio of anionic surfactant to nonionic surfactant is 5.
: 5 to 45% by weight of a ternary active system, and the amount of soap is 10 to 90% by weight of the active system. 2. Granular detergent according to claim 1, wherein the weight ratio of anionic surfactant to nonionic surfactant is less than 4:1 and the amount of soap is 10 to 60% by weight of the active agent system. Composition or ingredient. 3. A granular detergent composition or ingredient according to any of the preceding claims, having a bulk density of at least 650 g/l. 4. A granular detergent composition or component according to any of the preceding claims, wherein the builder is a non-phosphate builder. [Claim 5] Claim 4 wherein the builder is zeolite.
A granular detergent composition or ingredient as described. 6. A granular detergent composition or component according to any of the preceding claims, containing less than 5% by weight of silicates, preferably less than 2% by weight. 7. A granular detergent composition or component according to any of the preceding claims, which is substantially free of alkali metal sulfates. 8. A powder detergent comprising 50 to 95% by weight of the granular detergent composition or component according to any of the preceding claims. 9. The granular starting material is processed (i) in a high speed mixer/densifier with an average residence time of about 5 to 30 seconds, and then (ii) in a drying and/or cooling device. Item 8. A method for producing a granular detergent composition or component according to Items 1 to 7. 10. The method of claim 9, wherein the particulate starting material is brought into or maintained in a deformable state. 11. Process according to claim 9, wherein the deformable state is brought about by operating at a temperature above 45° C. and/or by adding a liquid to the particulate starting material. 12. The method according to claim 9, wherein the non-ionic substance and/or water are sprayed onto the particulate starting material. 13. A method according to claims 9 to 12, wherein the particulate starting material is a spray-dried detergent base powder.