JPH0762160B2 - Process for producing high bulk density detergent powder containing clay - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for producing a granular detergent composition or ingredient having a high bulk density and good powder properties. More particularly, the present invention relates to a method of making a granular detergent composition having good powder dissolution properties and good softening properties in laundry performance.

PRIOR ART In recent years, there has been considerable interest in the detergent industry in the production of laundry powder having a relatively high bulk density (eg 550 g / l and above).

Generally speaking, there are mainly two types of methods by which detergent powder can be produced. The first type of method is
Spray drying the aqueous detergent slurry in a spray drying tower. In the second type of method, the various components are dry mixed and optionally agglomerated with a liquid (eg a non-ionic substance).

The most important factor controlling the bulk density of the detergent powder is the bulk density of the starting material in the case of the dry mixing method and the chemical composition of the slurry in the case of the spray drying method. Both factors can be changed only within a limited range. For example, the bulk density of dry-mixed powders can be increased by increasing the utilization of relatively dense sodium sulfate, but since its content does not contribute to the detergent properties of the powder, it is generally used as a laundry powder in its entirety. Adversely affect the physical properties.

Thus, a substantial increase in bulk density can only be achieved by an additional processing step leading to densification of the detergent powder. Several methods are known in the art to provide this type of densification. Therefore, particular attention is paid to the densification of the spray-dried powder by post-tower processing.

For example, Japanese Patent Application No. 61-069897 (Kao) discloses a spray-dried detergent powder containing a high level of anionic surfactant and a low level of builder (zeolite) sequentially in a high speed mixer / granulator. Disclosed is a method of subjecting to a powdering and granulating process in a lathe. Granulation is carried out in the presence of a "drug improving surface properties" and optionally a binder.

Furthermore, it is also known to mix smectite-type clay into detergent powder in order to obtain a softening effect on the cloth. Furthermore, British Patent No. 2,063,289 (Uniriver Inc.) discloses that detergent powders containing less than 20% by weight of phosphate and more than 20% by weight of anionic surfactants are used in 1-15% of bentonite or kaolin. Is added to the ratcher slurry to make it hard and free flowing.

However, one of the inherent problems with detergent compositions having high bulk densities is that their dissolution properties are generally reduced compared to corresponding compositions having low bulk densities. This is believed to be due to the lower porosity of the powder particles.

Surprisingly, this time, the swelling clay was mixed with the granular detergent starting material, and this mixture was then treated with a high speed mixer / granulator with both stirring and cutting action to transform the clay into a clutcher slurry. It has been determined that a high bulk density detergent powder is obtained which has much better dissolution and softening properties than if mixed and then spray dried.

SUMMARY OF THE INVENTION The present invention is a method for producing a granular detergent composition or component having a bulk density of at least 550 g / l, wherein up to 35% by weight of swelling clay is (a) 10-70% by weight. Of a non-soap detergent active substance of (b) and (b) at least 10% by weight of a water-soluble crystalline inorganic salt containing sodium tripolyphosphate and / or sodium carbonate, added to components (a) and (b). ) With a weight ratio of up to 2.5, and further providing a method for producing a granular detergent composition or component, which comprises treating the mixture with a high speed mixer / granulator having both a stirring action and a cutting action. To do.

DETAILED DESCRIPTION OF THE INVENTION In the process of the invention, the particulate starting material is mixed with a swelling clay and then processed in a high speed mixer / granulator.

The starting materials used in the process of the present invention include (a) 10-70% by weight of non-soap detergent active material and (b) at least 15 sodium tripolyphosphate and / or sodium carbonate.
It contains water-soluble binder inorganic salt in an amount of wt% and the weight ratio of the components (a) and (b) is 2.5 at the maximum. Preferably, the ratio of components (a) and (b) is 0.1 to 2.0, more preferably 0.1.
~ 0.4.

The starting materials include, for example, the compounds conventionally used in detergent compositions such as detergent actives, builders and the like, all well known in the art.

Detergent active substances are non-soap type, anionic type, zwitterionic type,
It can be selected from zwitterionic or nonionic detergent actives or mixtures thereof. Particularly suitable are mixtures with all anionic or nonionic detergent actives, for example with alkali metal salts of alkylbenzene sulfonic acids and alkoxylated alcohols.

Suitable detergent compounds that can be used are synthetic anionic and nonionic compounds. The former are generally water-soluble alkali metal salts of organic sulphates and sulphonates with alkyl groups having about 8 to about 22 carbon atoms, where the term alkyl is used to include the alkyl part of higher acyl groups. It Examples of suitable synthetic anionic detergent compounds are those obtained sodium alkylsulfate and potassium, especially e.g. a higher (C ₈ ~C ₁₈₎ alcohols produced from tallow oil or cocoa榔子oil and sulfated; alkyl (C ₉ ~ C ₂₀ ) Sodium and potassium benzene sulfonate, especially linear secondary alkyl (C ₁₀ -C ₁₅ ) sodium benzene sulfonate; sodium alkyl glyceryl ether sulphate, especially higher alcohols derived from taroa oil or coconut oil and ethers synthetic alcohols derived from petroleum; here榔子oil fatty monoglyceride sodium sulfate and sulfonate; higher (C ₈ -C ₁₈₎ fatty alcohol - alkylene oxides (especially ethylene oxide)
Reaction products of sodium and potassium salts of sulfuric acid esters; reaction products of fatty acids such as coco coconut fatty acid esterified with isethionic acid and neutralized with sodium hydroxide; sodium and potassium fatty acid amides of methyl taurine Salts; alkane monosulfonates, such as those obtained by reacting α-olefins (C ₈ -C ₂₀ ) with sodium bisulfite and paraffins SO ₂ and Cl _2.
Those obtained by reacting with an olefin and then hydrolyzing with a base to give a random sulfonate; and an olefin sulfonate [this term reacts an olefin (particularly a C ₁₉ -C ₂₀ α-olefin) with SO ₃ and then Used to describe materials made by neutralizing and hydrolyzing reaction products].
Suitable anionic detergent compounds are (C ₁₁ -C ₁₅ ) sodium alkylbenzene sulphonate and (C ₁₆ -C ₁₈ ) sodium alkylsulfate.

Suitable nonionic detergent compounds which can be used are especially those having hydrophobic groups and reactive hydrogen atoms (eg aliphatic alcohols, acids, amides or alkylphenols).
And the alkylene oxide (especially ethylene oxide) alone or with a mixture with propylene oxide.
Certain nonionic detergent compounds are generally alkyl (C ₆ -C ₂₂ ) phenol-ethylene oxide condensates having 5 to 25E0 (ie 5 to 25 units of ethylene oxide per molecule); aliphatics generally having 5 to 40E0. (C ₈ ~C ₁₈₎ condensation products of primary or secondary linear or branched alcohols with ethylene oxide; and the reaction products and products prepared by condensing the ethylene oxide propylene oxide with ethylenediamine Is. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulfoxides.

Mixtures of detergent compounds, for example mixtures of anionic compounds or mixtures of anionic and nonionic compounds, can also be used in the detergent composition, especially in the latter case, which give suppressed low foaming properties. . This is advantageous for compositions intended for use in automatic washing machines that cannot withstand lathering.

Predetermined amounts of amphoteric or zwitterionic detergent compounds may also be used in the compositions of the present invention, but this is generally undesirable due to their relatively high cost. If an amphoteric or zwitterionic detergent compound is used, it is used in small amounts in the composition relative to the most commonly used anionic and / or nonionic synthetic detergent compounds.

The detergent builder can be any substance that can reduce the level of free calcium ions in the wash liquor, preferably for example the development of alkaline pH, suspension of soil removed from the fabric, and suspension of the fabric softening clay material. It imparts other advantageous properties to the composition, such as cloudiness. The amount of detergent builder can be 10 to 70% by weight, particularly preferably 20 to 50% by weight.

Examples of detergent builders are precipitating builders such as alkali metal carbonates, bicarbonates, orthophosphates; metallizable builders such as alkali metal tripolyphosphates or nitrilotriacetic acid salts; or amorphous, for example. Includes ion exchange builders such as alkali metal aluminosilicates or zeolites.

The starting materials can be prepared by any suitable method, such as spray drying or dry mixing. Further suitable granulates can also be prepared by the dry neutralization method, in which case a liquid acidic anionic surfactant precursor is reacted with a solid alkaline inorganic component, for example a carbonate. This type of dry neutralization method is described, for example, in British Patent No.
2,166,452 (Kao), 1,404,317 (Bell) or 1,369,269 (Colgate).

In the process of the present invention, the starting materials are fed to a high speed mixer / granulator which has both stirring and cutting action. A high speed mixer / granulator of the type suitable for use in the process of the present invention is of the bowl type and has a substantially vertical stirrer axis. This is particularly suitable if the mixer / granulator additionally has cutting means on the side wall. These stirring and cutting means are
Advantageously, they can be operated independently of one another and at different variable speeds. Further, it is preferable to attach a jacket for cooling or heating to the container of the mixer. As needed,
Cooling can also be provided by a low temperature unit.

An example of a suitable mixer is Fukae (registered trademark) FS-G series manufactured by Fukae Powtech Co., Ltd. (Japan), for example, Fukae FS30. The device is primarily in the form of a bowl-like container accessible through the top port and comprises a substantially vertical axis near the bottom of the unit agitator and a side wall cleaver.

A similar mixer manufactured in India is the Sapphire® RMG series of rapid mixers / granulators, which are available in a variety of sizes as well as Fukay-type mixers. This device is primarily in the form of a bowl-shaped container that is pneumatically elevated and sealed to a fixed lid. A 3-blade stirrer and a 4-blade cutter share a substantially vertical axis of rotation mounted on the lid. The stirrer and the cutter can be operated independently of each other, the stirrer at 75 rpm or 150 rpm, and the cutter at 1440 rpm or 3880 rpm.
It can be operated at the speed of. The container can be fitted with a water jacket that can be used to cool or heat the contents of the container.

Sapphire RM suitable for handling 60 kg batches of detergent powder
G-100 mixer has a bowl with a diameter of about 1 m and a depth of 0.3 m. The working capacity is 200l. The stirring blade has a diameter of 1 m and the cutting blade has a diameter of 0.1 m.

Other similar mixers found to be suitable for use in the method of the invention are Diosna® V series manufactured by Sierks & Sähne GmbH, West Germany;
Includes Pharma Matrix® from K. Fielder Limited. Other mixers that may be suitable for use in the method of the present invention are the Fuji (R) VG-C series from Fuji Sangyo Co., Ltd. (Japan); and the lotto from Zanchetta & Company srl, Italy. (Registered trademark).

Further mixers found to be suitable for use in the method of the present invention are the Logigue (TM) FM series batch mixers manufactured by Morton Machine Company Limited, Scotland. It differs from the above mixer in that the stirrer has a horizontal axis.

These devices, which can be continuous or batch fed, consist of a substantially large stationary hollow cylinder and a central rotating shaft. The shaft has several different types of vanes mounted on it. The rotation speed is variable and depends on the desired degree of densification and particle size. The vanes on the shaft provide a good mixing effect of the solids and liquids mixed at this stage. The average residence time depends to some extent on the rotational speed of the shaft and the position of the vanes with respect to the continuous plant. Independently driven high-speed cutting blades can also be integrated into this type of mixer and operated on the main agitator "for example the Rodige (R) KM series or the Dreis (R) KT series".

The use of a high speed mixer / granulator is important in achieving granulation and densification. Prior to granulating the starting material, a pretreatment, eg a pulverization step, can be carried out. Whether this is necessary depends in particular on the method of preparation of the starting material, its particle size and water content. For example, spray dried powders more often require powdering pretreatment than dry blended powders.
In order to carry out the pulverization, one has to select a suitable stirring / cutting method, which is generally characterized by a relatively high speed for both the stirrer and the cutter and a relatively short residence time, for example 1 to 4 minutes.

Similarly, the granulation step is performed by operating the stirrer and the cutter at relatively high speeds, but this requires the presence of a liquid binder. The preferred binder is water. The amount of binder added should preferably not exceed 6% by weight. This is because higher amounts adversely affect the flow properties of the final product. The liquid binder may be added prior to or during granulation by spraying, preferably while the equipment is operating. In addition, the starting material may already contain a sufficient stream of water so that the addition of other liquid binders may not be necessary. In this case, pulverization and granulation can be carried out in a single operation.

According to a preferred embodiment of the invention the granulation is carried out at temperatures above room temperature, eg above 30 ° C or 45 ° C. For example, spray dried detergent base powder exiting the tower at temperatures of about 45 ° C. or higher can be fed directly to the process of the present invention. Of course, the spray-dried powder can also be cooled first, for example by air lift.

In the method of the present invention, swelling clay (swelling cla
y) is added to the mixer / granulator in an amount of up to 35% by weight, based on the starting material. The swellable clay material can be any material of this type that can provide fabric softening properties. Generally, these materials are of natural origin containing three layers of swellable smectite-type clay. Preferably the clay is of the calcium and / or sodium montmorillonite type.

The effectiveness of clay-containing materials as fabric softeners depends especially on the level of smectite-type clay. Calcite, for example,
Impurities such as fluorspar and silica are often present.
Relatively impure clays can also be used as long as such impurities are acceptable in the composition.

The amount of fabric softening clay material in the composition should be sufficient to impart softness. Amounts of 1.5 to 35% by weight, calculated on the clay mineral itself, have been found to be effective.

Besides detergent actives, detergent builders and clay-containing substances,
The composition according to the invention may optionally also contain other ingredients commonly found in detergent compositions, the amount being such that additives of this type are generally used in laundry detergent compositions in the prefecture. Is. Examples of such additives are suds boosters (eg alkanolamides, especially monoethanolamides derived from palm kernel fatty acids and coco coconut fatty acids), suds suppressors, oxygen-releasing bleaches (eg sodium borate and peroxides). Sodium carbonate), peracid bleach precursors, chlorine-releasing bleaches (eg trichloroisocyanuric acid), fillers (eg sodium sulphate), and fluorescent agents, fragrances, enzymes (eg proteases, lipases and amylases) generally present in very small amounts. ), Bactericides and colorants.

The process of the invention allows the production of detergent compositions having a high bulk density of at least 550 g / l. The surprising advantage of the method according to the invention is that the bulk density of the powder obtained is higher than when the clay is mixed in the clutcher slurry before spray drying the starting material.

Another advantage of the method according to the invention is that the softening effect of the final detergent powder is improved over when the clay is mixed in the clutcher slurry and then spray dried. This effect of the method according to the invention can be confirmed by the method used in evaluating softening properties as described in the prior art.

Another advantage of the method according to the invention is that the storage stability of the final detergent powder is improved. This can be confirmed by the infinite compressibility test (UCT). In this test, detergent powder is placed in a cylinder having a diameter of 13 cm and a height of 15 cm. Then a 10 kg weight is placed on top of the powder. After 5 minutes, remove the weight and remove the cylinder wall. Then, a load is gradually applied to the top of the column of the compressed detergent powder to determine the weight (kg) at which the column collapses. This value is related to the tackiness of the detergent powder and was found to be a good measure of storage stability.

[Examples] The present invention is further described below with reference to non-limiting examples.
Parts and percentages are by weight unless otherwise stated.

In the following examples the following abbreviations are used for the materials used: LAS: linear alkylbenzene sulfonate STP: sodium tripolyphosphate silicate: alkaline sodium silicate carbonate: sodium carbonate sulfate: sodium sulfate clay: calcium or sodium montmorillonite.

Examples 1 to 3 The following detergent powders were prepared by spray drying the aqueous slurry. The composition (% by weight) of the powder thus obtained is shown below.

The composition of Example 2 contained Ca-clay (Plasa, Choline Stewart Minerals, UK), which was added to the clutcher slurry and spray dried. In this case, sodium carbonate was omitted from the slurry to maintain it at a sufficiently low viscosity to facilitate spray drying. Example 3 was a spray-dried powder that contained no carbonate but carbonate.

The compositions of Examples 2 and 3 contain higher weight percentages of LAS, STP and silicates than the composition of Example 1 and allow for a subsequent dilution of carbonate or clay during the densification / granulation process, respectively. I chose

These powders were added to a Fuukae FS-30 type high speed mixer / granulator (10 kg-Example 19.2 kg-Example 2; 9.0 k).
g-Example 3). The powders were pulverized at 70 ° C. for 2 minutes at a stirrer speed of 300 rpm and a cutter speed of 3000 rpm. Then 0.8 kg of sodium carbonate
1.0 kg of Ca-clay was added to the densified powders of Examples 2 and 3. Granulation was then carried out by adding 150 ml of calcined water at a stirrer speed of 275 rpm and a cutter speed of 3000 rpm for 1 minute. Of the powders obtained, those with an oversized size (> 1700 μm) were sieved. The composition (wt%) of these powders was as follows: The powder properties of the screened material are shown in Table 3 below.

[UCT is% unlimited compressibility and N is the distribution of average particle size].

The dissolution properties of the concentrated powder and the non-densified control powder shown in Tables 2 and 3 respectively were measured by standard conductivity measurement techniques. A fraction of the screened powder sample (-500 + 425 μm) was used to compare the dissolution characteristics of the four competing particle size ranges. The rates of dissolution were compared to the ratio SA _g / SA _b to compensate for inevitable differences in powder properties such as bulk density. Here SA is the surface area per unit weight of a given granulated powder (g) or undensified base (b). The ratio SA _g / SA _b thus represents a measure of densification. The surface area (SA) per kg for a specific powder was calculated from the following formula: SA = 6 / (BD × d _m ) [where BD represents bulk density and d _m represents mean diameter (μm)] (Assuming spherical particles).

The results of the dissolution experiments are shown in Table 4 and graphically in Figure 1. In this figure, a linear relationship between the dissolution rate and the ratio SA _g / SA _b is observed for the densified powders from Examples 1 and 2 and the undensified base powder of Example 1. This indicates that the dissolution rate is a function of the surface area available for mass transfer. This figure shows that in Example 3 where clay was post-dosed prior to granulation, the dissolution rate was higher than expected for similar powders. This indicates that clay contributes to the improvement of dissolution properties.

Table 4 also shows the softening properties of various compositions.
The softening of the densified powders of Examples 1-3 was measured on a terry towel cloth. A tergotometer wash at a powder concentration of 3.6 kg / l was performed for 30 minutes with a 1:20 weight ratio of cloth to liquid. The degree of relative softening was measured according to standard methods by a panel of 10 people, as described in the prior art.

The excellent softening properties of the composition of Example 3 according to the invention, where the clay was post-administered during granulation, are due to the addition of clay powder to Example 1 at the same concentration as in Example 3 during washing. It can also be illustrated by a comparison experiment of.

A softness value of 97.5 was measured when clay was added separately to the laundry using the composition of Example 1. Comparison of this value with the softness value of 99.5 found in Example 3 shows that the method of the present invention provides sufficient softening performance. However, when clay was added to the clutcher karary prior to spray drying as in Example 2, a much lower softness value of 75.3 was observed.

[Brief description of drawings]

 FIG. 1 is a characteristic curve diagram showing the results of dissolution experiments.

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Claims (6)

[Claims] 1. A method for producing a granular detergent composition or component having a bulk density of at least 550 g / l, which comprises 1.5-35.
At least 10% by weight of a swelling clay consisting of weight% sodium montmorillonite and / or calcium montmorillonite; % Of water-soluble crystalline inorganic salt, and added to a granular starting material having a weight ratio of components (a) and (b) of up to 2.5, and further adding a mixture having a stirring action and a cutting action. A method for producing a granular detergent composition or component, which comprises treating with a speed mixer / granulator. 2. A process according to claim 1, wherein the ratio of components (a) and (b) is 0.1 to 2.0, preferably 0.1 to 1.0. 3. A process according to claim 1 or 2, wherein the mixer / granulator is a bowl type high speed mixer / granulator having a substantially vertical stirrer axis. 4. The method according to claim 1, wherein the particulate starting material comprises spray dried detergent powder. 5. The process according to claim 1, wherein the particulate starting material comprises 15 to 50% by weight sodium tripolyphosphate. 6. The method according to claim 1, wherein the granulation is carried out at a temperature of 45 ° C. or higher.