JPH0668120B2 - Granular laundry detergent composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel granular laundry detergent composition containing no or little inorganic phosphate compounds. The present invention also relates to a particulate base material suitable for use in detergent compositions of this type and a method for producing said granular base material.

BACKGROUND OF THE INVENTION Conventional laundry detergent compositions include phosphate compounds, especially sodium tripolyphosphate (STP), as builders. In recent years, in view of the adverse effects of phosphate compounds on the environment, development of new laundry detergent compositions containing little or no phosphate has become active. However, it is difficult to produce a composition having properties comparable to the excellent builder properties of phosphate-containing compositions.

As is well known, zeolites are used as builders in phosphorus-free laundry detergent compositions. However, the use of zeolites in laundry detergent compositions presents many problems. That is, zeolites tend to exacerbate the powder structure, and are more likely to interact with silicates, which are usually present as corrosion inhibitors in detergent compositions, resulting in washing machine dispensing problems and laundry. Cause the problem of deposits on.

SUMMARY OF THE INVENTION The present invention provides novel low phosphorus or phosphorus free granular laundry detergent compositions that do not use zeolites. The composition of the present invention uses acidic soaps as a powder base and builder.

The composition of the present invention comprises a fatty acid mixture as the first particulate material. This mixture may contain up to 35 mol% unsaturated fatty acids and has been neutralized to 25-60 mol%. The composition of the present invention further comprises, as a second particulate material, the pH of the composition.
Of the base material in a concentration of 0.5% by weight in water.

The compositions of the present invention may also optionally include conventional additives such as bleaching systems, proteolytic enzymes, defoamers, optical brighteners, perfumes, corrosion inhibitors and the like.

The composition of the present invention exhibits extremely high cleaning performance without using a builder made of phosphate or zeolite. However, it is possible and effective to use these builders at low concentrations. The composition of the present invention also has excellent powder properties such as flowability and compressibility. The granular laundry detergent composition of the present invention preferably contains 30 to 80% by weight of acidic soap particles.

The acidic soap is a mixture of free fatty acids and soaps, or a partially neutralized mixture of fatty acids. In principle, a wide range of saturated and / or unsaturated fatty acids can be used, but the powder properties of the granular composition are that the unsaturated fatty acid content is 35
It has been found that if it exceeds mol%, it is not so preferable. That is, such powders are tacky and have little fluidity. The acceptable proportion of unsaturated fatty acids is higher the smaller the proportion of saturated fatty acids with a chain length of less than 14 carbon atoms.

Fatty acid mixtures are mainly C16-C18 unsaturated fatty acids 5-20
Mol% and 95-80 mol% C8-C14 saturated fatty acids and C16-C1
It is preferred to include 95-80 mol% of a mixture of 8 saturated fatty acids in the ratio 3: 1 to 1: 2.

In the present specification, C8-C14 saturated fatty acids are also referred to as lauric acid, C14-C16 saturated fatty acids are also referred to as stearic acid, and C1
6-C18 unsaturated fatty acids are also called oleic acid.

In the fatty acid mixture, the C16-C18 saturated fatty acid or stearic acid mainly plays the role of a builder, and hardly contributes to the detergency. C16-C18 unsaturated fatty acids or oleic acid also have builder properties, but play an important role especially with regard to detergency. C8-C14 saturated fatty acids or lauric acid contribute to both builder properties and detergency, but their main role is to facilitate processing of the soap / fatty acid mixture and to provide proper solubility.

The laundry detergent composition of the present invention can be produced by dry blending various components into an appropriate mixture.

In the present invention, acidic soaps are used in the form of particulate material such as particles or noodles. The size and size of the particles can be optionally laundered. This will be described in detail later. These acidic soap particles can be produced by dissolving a suitable amount of soap in a molten fatty acid mixture, solidifying it and processing the resulting solid material. Alternatively, it can be prepared by partially saponifying or neutralizing the fatty acid mixture in situ. In this method, the solid base material is gradually mixed with the molten fatty acid mixture.
Suitable base materials include, for example, soda ash (sodium carbonate), sodium disilicate, sodium metasilicate or sodium hydroxide. With soda ash
CO ₂ only generates as a by-product, the CO ₂ can be easily removed from the reaction mixture. The use of sodium alkaline silicate can increase the viscosity of the molten soap / fatty acid mixture due to the formation of insoluble silicates. In contrast, incorporation of the silicate directly into the soap / fatty acid mixture gives favorable powder properties and avoids the problems encountered when dry blending the silicate as it is. The operating temperature required to process these mixtures increases with increasing fatty acid chain length and degree of neutralization, and is preferably 70-140 ° C.

The detergent composition of the present invention further has a pH of the composition of 0.5 in water.
Also included is an amount of particulate base material sufficient to be greater than 8 at a weight percent concentration. As base substance, in principle, any base substance which can be prepared in granules and which readily dissolves in water without forming a precipitate with the soap fatty acid particles can be used. Preferably, the same basic substance as that used for the partial neutralization of the fatty acid mixture is used.

The laundry detergent composition of the present invention may further comprise other detergent compounds such as anionic and / or nonionic non-soap cleaning active compounds. These detergent compositions may be incorporated into the granular acidic soap base or present as a separate ingredient. The acidic soap particles may contain up to 10% by weight of anionic and / or nonionic surfactants. Higher amounts can adversely affect powder properties.

Alternatively, or additionally, an anionic or nonionic surfactant, in particular a nonionic surfactant, may be retained by a porous inorganic material mixed with acidic soap particles. Specific examples of this type of additive include liquid ethoxylated C13-C15 alcohols sprayed onto burkeite carriers. If the inorganic carrier is a basic substance, this additive functions as the basic substance component (second particulate material) of the composition.

It has been found that a particularly preferred method of making acidic soap particles is spray cooling. This method can be used to produce particles or prills with excellent properties in terms of dissolution rate, stability and cleaning performance of the final detergent composition.

The spray cooling method can be used to produce particles having a desired size and bulk density by adjusting the operating conditions. The particles are segregated within the packaging container.
n) is minimized, in view of compatibility with other solid components in the composition, an average particle size of 250-1000 μm and 400-75 μm.
It preferably has a bulk density of 0 g / e.

In addition to builder / activity and solubility requirements, a number of factors need to be considered when producing particles by spray cooling a soap / fatty acid mixture: 1. Proper handling properties. And in order to obtain storage properties, the soap / fatty acid mixture must exhibit a sufficient solid state at temperatures below 35-40 ° C.

2. For processing reasons, it is preferable that complete liquefaction is possible at temperatures below 100 ° C. This means that in actual operation, the maximum mixing temperature is below 150 ° C. To meet this condition, it was found that the soap content of the mixture had to be limited to 25-60 mol% depending on the fatty acid composition.

3. The composition of the mixture in terms of fatty acid type and degree of neutralization should be such that it exhibits suitable solubility at low washing temperatures of 20-40 ° C.

As will be appreciated by those skilled in the art, meeting all of these conditions at once is not straightforward. This is because many properties of soap / fatty acid mixtures have to be taken into account.

First, soaps and fatty acids are eutectic in various eutectic complexes.
complexes) can be formed. Such complexes can also be formed between soaps and fatty acids, so that these mixtures show a very complex phase diagram. This is especially a problem in that it has to exhibit a solid state at 35-40 ° C. It has also been found that the relative amounts of lauric acid and stearic acid should not exceed a ratio of preferably 1: 1. Nevertheless, it is unavoidable that some liquefaction will occur at the eutectic temperature of about 33 ° C. Although not ideal in terms of ease of handling / stability, the introduction of some low melting point lauric / stearic acid complex can be expected to have a beneficial effect on solubility at low temperatures.

Second, the structure becomes more complex due to the metathesis phenomenon. The addition of soap to the fatty acid mixture results in an equilibrium reaction, which results in the soap and free acid being present in specific ratios in all chain length homologues, depending on the reactivity of the individual acids. Fortunately, in these mixtures, the reactivity of the unsaturated acids and the reactivity of the saturated acids are different, so that in practice the oleic acid is preferentially converted to soap. Large amounts of lauric and stearic soaps can only be present when the proportion of soap exceeds that of oleate.

Hereinafter, the present invention will be described in more detail with reference to examples.

Examples 1-3 A fatty acid mixture having the composition described in Table A was prepared. Upon heating these mixtures, they started to melt at about 65 ° C. Heating was continued and after complete melting at about 80 ° C. soda ash (sodium carbonate) was slowly added at a rate of 0.1 kg / min to control the evolution of CO 2 while the mixture was neutralized to the desired degree. At the same time, the temperature was gradually increased to about 140 ° C.

The partially neutralized fatty acid mixture was then cooled and solidified. The coagulum was made into noodles using a sodium press. A noodle with a diameter of 1 mm and a length of about 5 mm was obtained. The properties and handleability of these noodles are shown in Table A. Solubility was measured by examining the dissolution rate of soap / fatty acid noodles by monitoring the increase in conductivity caused by the dissolution of the soap portion of these noodles. In this method, while stirring with a magnetic stirrer, a sample of 3 g / 25
At 0 ° C. was added into deionized water 1. The dissolution rate is expressed as the time required for 50% of the soluble part of the soap / fatty acid mixture to dissolve (t1 / 2). Maximum conductivity is measured when heated above the melting point of fatty acids and then cooled to room temperature. As is clear from Table A, these noodles were easy to handle and had high solubility.

Examples 4-6 It operated like Example 1-3. However, in this case the particles were produced by spray cooling the molten acid / soap mixture in a spray tower. The spray cooling conditions are as shown in Table B.
The powder properties of the resulting particles are shown in Table C.

Table B Spray cooling conditions Air volume: 7,000 kg / h Tower pressure: -2 / -10 mmH20 Nozzle pressure: 1/8 bar Throughput: 60-150 kg / h Liquid temperature in tank: 86-120 ° C Inflow air temperature (countercurrent): 22-24 ℃ Outflow air temperature: 22-25 ℃ Particle temperature at the bottom of the tower: 27-33 ℃ Nozzle height: 12m As is clear from the comparison between Examples 1 to 3 and Examples 4 to 6, when the partially neutralized fatty acid mixture is spray-cooled, particles having high solubility and excellent powder characteristics are obtained.

Example 7 A fatty acid mixture having the following composition was prepared: Oleic acid: 20% by weight C12-C14 fatty acids: 45% by weight Stearic acid: 35% by weight These mixtures were heated to 65 ° C. and solid carbonic acid was added while heating. Sodium was added until a saponification degree of 33% was reached. Then, at the temperature of 110 ° C. according to the conditions in Table B, the molten soap /
The fatty acid mixture was spray cooled.

As a result, as shown in Table D, high density particles having extremely preferable powder handling property were obtained.

Example 8 The procedure of Example 7 was repeated with a fatty acid mixture of the following composition: Oleic acid: 30% by weight C12-C14 fatty acids: 40% by weight Stearic acid: 30% by weight Melted with solid sodium disilicate. The fatty acid mixture was partially neutralized and then spray cooled. The obtained particles had the characteristics shown in Table D and were extremely easy to handle.

Example 9 Final Laundry Detergent Composition by Dry Blending Acid Soap Particles Made in Example 7 with Various Other Ingredients, eg Nonionic Detergent, Bleaching System and Enzyme Retained in Berkeite Carrier Was manufactured.

The composition of this final detergent powder is shown in Table E. The table also shows two types of commercially available laundry detergent compositions. Composition B is low phosphorus, composition A is phosphorus free, both using zeolites.

The cleaning performance of these three compositions was measured using a Zanussi ZF822W top loading drum washing machine according to the standard 40 ° C cotton cycle program "C". Laundry with a mixture of clean cotton cloth and moderately soiled cloth 2.
5 kg was washed with a liquid / cloth ratio of about 6. Water temperature is 20
The temperature and pressure were 2.0 kg / cm ² . Water hardness is 9, ie 25 °
It was GH. Detergent powder was added at a dose of 7.5 g /. The reflectance (R * 460) of the test cloth before and after washing was recorded.

Table F shows the results of testing four tested fabrics, including standard EMPA-101 and WFK-10C fabrics, at two different water hardnesses.
As is clear from these results, extremely high cleaning performance was observed even with high water hardness, despite the absence of phosphate or zeolite builder.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Marco Wats, Netherlands, Rotterdam, St. Jacobstraat 137 (72) Inventor Simon Willems, Netherlands, 3131 Itux Elf Laerdeinhen, Sriname Singher 31 ( 56) References JP-A-54-87707 (JP, A) British patent 1287625 (GB, A)

Claims (15)

[Claims] 1. An unsaturated fatty acid which may contain up to 35 mol% 25-
The first particulate material comprises a fatty acid mixture neutralized to 60 mol% and a sufficient amount of a basic substance as a second particulate material to bring the pH of the composition to greater than 8 at a concentration of 0.5% by weight in water. Granular laundry detergent composition. 2. A partially neutralized fatty acid mixture of 30-80%
A granular laundry detergent composition according to claim 1 comprising. 3. The fatty acid mixture is mainly composed of 5 to 20 mol% of C _{16 to} C ₁₈ unsaturated fatty acids, C _{8 to} C ₁₄ saturated fatty acids and C ₁₆ to C _16.
A granular laundry detergent composition according to claim 2, comprising 95-80 mol% of a mixture of ₁₈ saturated fatty acids in a ratio of 3: 1 to 1: 2. 4. The granular laundry detergent composition according to claim 1, wherein the basic substance is sodium carbonate or sodium alkali silicate. 5. The granular laundry detergent composition according to claim 1, further comprising a non-soap detergent active substance. 6. The granular laundry detergent composition according to claim 5, wherein the first granular material contains up to 10% by weight of anionic and / or nonionic detergent substances. 7. The granular laundry detergent composition according to claim 5, which comprises a liquid nonionic substance retained in a porous inorganic carrier. 8. The granular laundry detergent composition according to claim 1, further comprising a peroxide bleaching system and / or an alkali sodium silicate and / or a defoaming compound and / or an enzyme. 9. A granular material suitable for use as a base powder for producing a granular laundry detergent composition, which comprises from 25 to 60 mol% of unsaturated fatty acids and can contain up to 35 mol%.
Granular material consisting of a mixture of fatty acids neutralized to. 10. A fatty acid mixture comprising mainly 5 to 20 mol%
C ₁₆ -C ₁₈ unsaturated fatty acids and 95 to 80 mol% of C ₈ -C ₁₄ saturated fatty acid and C ₁₆ -C ₁₈ ratio of saturated fatty acid 3: 1 to 1: according to claim 9 comprising a mixture of 2 Granular material. 11. A granular acidic soap composition comprising the granular material according to claim 9 or 10 and having the shape of particles or noodles. 12. The granular material according to claim 9, wherein the degree of neutralization is 30 to 40 mol%. 13. A method for producing a granular material according to claim 9, wherein the fatty acid mixture optionally containing one or more soaps is melted and, if necessary, the basic substance is added to partially mix the mixture. Neutralizing the mixture and converting the mixture into a granular solid form. 14. The method of claim 13 wherein the particulate material is produced by subjecting a partially neutralized molten fatty acid mixture to spray cooling to form particles. 15. Process according to claim 13 or 14, characterized in that the fatty acid mixture is partially neutralized by adding sodium carbonate and / or sodium alkali silicate.