WO1993017089A1

WO1993017089A1 - Process for producing low-alkaline dishwasher rinsing agents without active chlorine, silicates and phosphates, in the form of heavy granulates

Info

Publication number: WO1993017089A1
Application number: PCT/EP1993/000335
Authority: WO
Inventors: Hans Josef Beaujean; Willi Buchmeier; Birgit Burg; Jürgen Härer; Thomas Holderbaum; Franz Hundgeburt; Jochen Jacobs; Peter Jeschke; Hans Kruse
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1992-02-20
Filing date: 1993-02-11
Publication date: 1993-09-02
Also published as: EP0626996A1

Abstract

Production of phosphate-free dishwasher rinsing agents containing builders, bleaches, water, possibly non-ionic tensides and other customary components, in which the builders are powdered or liquid ANd sodium salts of monomeric or copolymeric (meth)acrylic acids which are premixed with sodium carbonate and sodium bicarbonate, preferably in concentrated form, and agglomeratively granulated with the addition of liquids. The granulate obtained is reduced in a second granulation stage to a uniform grain distribution, dried with agitation in a stream of hot air, sieved and then mixed with bleach and possibly with a bleach activator, bleach stabiliser, perfume, enzymes, non-ionic tensides and other builders.

Description

"Process for the production of low-alkaline, active chlorine, silicate and phosphate-free dishwasher detergents in the form of heavy-duty granules"

The invention relates to a new process for the production of machine washable dishwashing detergents free of low alkali, active chlorine, silicate and phosphate in the form of storage-stable, free-flowing, dust-free granules with high bulk densities - in particular in the range from about 750 to 1,100 g / l.

In the course of the ecological renunciation of phosphates or ^" polyphosphates" in washing and cleaning agents, these substituting framework substances are constantly being developed and optimized. In addition, the labeling of cleaning agents that comply with the EC preparation guidelines can be expected shortly of "irritating" substances such as alkali carbonate plus alkali perborate plus surfactant do not exceed 20% by weight of the total agent. Finally, agents are desired which should not be declared as "irritant" or "caustic". Therefore they should be "irritating" alkalis if possible only contained in amounts that do not require labeling, however, such dishwashing detergents are expected to have an undiminished good cleaning performance.

For the process according to the invention, powdery poly (meth) acrylate with an active substance content of about 92-95% by weight and / or a granular alkali cleaning additive based on sodium salts of homopolymers or copolyers (meth ) acrylic acids used, the subject of German Offenlegungsschrift 39 37469. It consists of:

(a) 35 to 60% by weight of sodium salts of at least one homopolymeric or copolymeric (meth) acrylic acid,

(b) 25 to 50% by weight of sodium carbonate (calculated as anhydrous),

(c) 4 to 20% by weight sodium sulfate (calculated as anhydrous) and Z,

(d) 1 to 7 wt .-% water, preferably from

(a) 40 to 55% by weight, in particular 45 to 52% by weight,

(b) 30 to 45% by weight, in particular 30 to 40% by weight,

(c) 5 to 15% by weight, in particular 5 to 10% by weight, and

(d) 2 to 6% by weight, in particular 3 to 5% by weight, of the compounds mentioned above.

On the basis of such cleaning additives, low-alkaline active chlorine and phosphate-free machine dishwashers containing calcium-binding framework substances, soda, water glass, solid per compounds, activators and surfactants and, if appropriate, other conventional constituents of such agents are in the form of a storage-stable, free-flowing, dust-free Granules with bulk densities required for practical use above 650 g / l have been developed, which were premixed with at least a portion of the liquid components and, if desired, a portion of the finely divided solid components of the machine dishwashing detergent in a first stage and then combined with the remaining components of the machine dishwashing detergent are. They have bulk densities in the range from 750 to 1,000 g / l and are the subject of the older, unpublished German patent applications P 4110510.9 and P 4137470.3.

In the dishwashing detergents produced according to P 41 10 510.9, intermediate storage can result in the moist granules caking in the pile. This aggregate does not completely disintegrate into the original granulate structure when loosening, which leads to a larger average grain diameter and a lower bulk density. In this regard, the present invention represents an advantageous further development of the older method.

The process for the production of dishwashing detergents according to German patent application P 4137470.3, which has been further developed in comparison, also relates to low-alkaline, active chlorine and phosphate-free detergents for automatic dishwashing with a content of granular, alkaline cleaning additives according to German published patent application DE 39 37 469, further builders such as silicates, bleaches, water and possibly low-foam nonionic surfactants, enzymes, bleach activators, fragrances and / or dyes, using powdered poly (meth) acrylate and / or the granular, alkaline cleaning additives with compressed sodium carbonate and premixed further builders, granulated agglomerating with water and optionally with further liquid constituents in a manner known per se, the granules then mixed with the bleaching agent and optionally with a bleach activator, fragrance, enzymes and / or dye, the resultant still slightly sticky granules dusted with powdered sodium carbonate, and finally sprayed with the proportion of nonionic surfactants, as a result of which excess sodium carbonate is bound and product dedusting takes place. The admixture of the sodium carbonate in turn prevents the granules from quickly caking in the pile. This maintains the granulate structure on the way to the swirl channel in the drying zone. Dusting with sodium carbonate powder additionally increases the liter weight to 850 to 1,000 g. A further increase in the liter weight is achieved if the granulation is carried out first with the addition of liquid water glass and then water or water alone, if the sodium carbonate introduced in the granulation step is partially hydrated or if the batch size is increased. The dishwashing detergents produced by this process contain silicates. The object of the invention was, inter alia, the production of silicate-free formulations.

It has now been found that mild, low-alkaline, active chlorine, silicate and phosphate-free cleaning agents for machine dishwashing, which contain builders, bleach, water, optionally nonionic surfactants and other substances customary for such agents, are obtained if Builders sodium salts of homo- or copolymeric (meth) acrylic acids with sodium carbonate and sodium bicarbonate in any mixer, for example in a ploughshare mixer, and then with the addition of liquids such as water, a nonionic surfactant or liquid poly (meth) acry _. granulated lat agglomerate, the granules thus obtained optionally adjusted to a uniform grain distribution in a second granulation stage, it under Movement in a warm air stream dries, fine and coarse fractions are sieved off and then mixed with the bleaching agent and, if appropriate, a bleach activator, a bleach stabilizer, fragrance, enzymes, nonionic surfactants, further builders and / or dyes

Since the alkali carbonate content is included in the EC preparation guidelines, the drying must be carried out in such a way that the bicarbonate decomposition of the sodium bicarbonate to sodium carbonate is as low as possible (or at least as constant as possible). An additional portion of sodium carbonate resulting from the drying would have to be taken into account in the formulation of the granule formulation. Low drying temperatures not only counteract sodium bicarbonate decay, but also increase the solubility of the granulated detergent during use. It is therefore advantageous for drying to have a supply air temperature which, on the one hand, should be as low as possible to avoid bicarbonate decomposition and, on the other hand, must be as high as necessary in order to obtain a product with good storage properties. A supply air temperature of approximately 80 ° C. is preferred during drying. The granules themselves should not be heated to temperatures above about 60 ° C. In contrast to the manufacturing process, the disintegration of the sodium bicarbonate is definitely desirable for later use in the cleaning process in the dishwasher, since this increases the alkalinity of the liquor and thus its cleaning performance. The in situ formation of sodium carbonate (irritating to the eyes and skin) from sodium bicarbonate (non-irritating) mitigates dangers for the consumer, e.g. in the event of improper use by children.

Sodium citrate is particularly suitable as a further structural substance. It can already be added in the granulation, but can also be added to the granulate after the drying and subsequent sieving stage, just like the other constituents of dishwashing detergents. These include bleaches, optionally bleach activators, bleach stabilizers, enzymes, dyes and fragrances.

The following ranges, which relate to the active substance content in percent by weight, are suitable for frame formulations of virtually all possible constituents of the granular cleaning agents produced according to the invention:

Setting the pH values to about 9.0 - 10.0 via the alkali carbonate / bicarbonate buffer system is important for preventing limescale deposits on the interior of the machine or on the wash ware in areas with particularly high water hardness or in softening systems that are not used properly Dishwashers.

The poly (meth) acrylates can be used as powder, but preferably in granulated form. The usable polyacrylates include Alcosperse (Alco: AlcosperseQv 102, 104, 106, 404, 406); Acrylsole® from Norsohaas: Acrysole® A IN, LMW 45 N, LMW 10 N, LMW 20 N, SP 02N, Norasole® WL1, WL2, WL3, WL4, Degapas® from Degussa; Good-RiteCüv'K-XP 18 from Goodrich. Copolymers of polyacrylic acid and maleic acid (poly (meth) acrylates) can also be used, for example SokalaneQy from BASF: SokalanQ / CP 5, CP 7; AcrysoleQ from Norsohaas: Acrysol QR 1014, Alcosperse (5) from Alco: Alcosperse® 175; granular alkaline cleaning additive according to DE 3937469. Anhydrous trisodium citrate or trisodium citrate dihydrate are suitable as sodium citrate. Trisodium citrate dihydrate can be used as a powder. It then has an average grain size of about 0.2 now. However, higher bulk densities are achieved with crystalline citrate.

Anhydrous sodium carbonate of any quality is expediently used as the alkali carbonate, e.g. calcined soda or compacted soda. Compacted soda is granular calcined sodium carbonate which is commercially available (e.g. V-soda from Matthes & Weber). The alkali bicarbonate is preferably sodium bicarbonate. The sodium bicarbonate should preferably be used in coarse compact form with a grain size in the main fraction between 0.4 and 1.0 mm.

For some time now, active oxygen carriers have been the preferred bleaching agent components of detergents for household dishwashing machines (HGSM). These primarily include sodium perborate mono- and tetrahydrate as well as sodium percarbonate. Compacted sodium perborate monohydrate is preferred because of the increase in bulk density. Since active oxygen only develops its full effect on its own at elevated temperatures, so-called bleach activators are used to activate it at about 60 ° C., the temperatures of the cleaning process in the HGSM. Preferred bleach activators are TAED (tetraacetylenediamine), PAG (pentaacetylglucose), DADHT (1,5-diacetyl-2,2-dioxo-hexahydro-1,3,5-triazine) and ISA (isatoic anhydride). In addition, the addition of small amounts of known bleach stabilizers such as phosphonates, borates or metaborates and metasilicates may also be useful.

Extremely low-foaming compounds are usually used as nonionic surfactants, which serve to better detach fatty food residues and as granulation aids. These preferably include C12-C18 "alkylpolyethylene glycol polypropylene glycol ethers, each with up to 8 moles of ethylene oxide and propylene oxide units in the molecule. However, other non-foaming surfactants known as low-foaming, such as, for example, Ci2-Ci8-alkylpolyethylene glycol polybutylene glycol ethers, each with up to to 8 moles of ethylene oxide and butylene oxide units in the molecule, as well as the foaming but ecologically attractive C 1 -C 4 -alkyl polyglucosides and / or - C 1 -C 4 -alkyl polyethylene glycols with 3-8 ethylene oxide units in the molecule with a degree of polymerization of about 1-4, these then together with about 0.2 to 4, preferably 0 , 2 to 2% by weight, based on the finished cleaning agent, of defoaming agents such as silicone oils, mixtures of silicone oil and hydrophobized silica, paraffin oil / Guerbet alcohols and hydrophobized silica. Cβ-Cio-alkyl polyglucosides with a degree of polymerization of about 1-4 can be used. In order to ensure a uniform distribution of the alkyl polyglucosides, they have to be diluted to about 35% active substance in order to lower their viscosity. In addition, a bleached quality should be used, otherwise a brown granulate will result.

For better detachment, protein or starch-containing food residues can be used as other common components of such agents. for example, enzymes such as proteases, amylases and lipases can also be used, for example proteases such as BLAP®140 from Henkel; Opitmase® -M-440, Optimase® -M-330, Opticlean® -M-375, Opticleanv! Y -M-250 from Solvay Enzymes; Maxacal®.CX 450,000, Maxapem® from Ibis, Savinase®4.0 T 6.0 T 8.0 T from Novo or Experase® T from Ibis and amylases such as Termamyl® 60 T, 90 T from Novo; Amylase-LT® from Solvay Enzymes or Maxamyl® P 5000, CXT 5000 or CXT 2900 from Ibis, lipases such as Lipolase®30 T from NOVO.

B e i s p i e l e

In the examples below,

AS: active substance

Plurafac® LF 403: alkyl (Ci2-Ci8) -polyethylene glycol (<8 E0) -polypropylene-glycol - (<8 P0) -ether (BASF)

APG 225: Cs-Cio fatty alcohol polyglucoside with a degree of polymerization of

1-4, bleached.

Sokalan®CP 5: poly (meth) acrylate (BASF)

Norasol WL 4: polyacrylate / soda granulate (Norsohaas)

Example 1:

12.6 kg of granular cleaning additive according to DE 39 37 469 with approx. 50% AS,

21.7 kg of compacted sodium bicarbonate with a bulk density of 900-1000 g / 1 and 2.9 kg of compressed soda were premixed in a discontinuous ploughshare mixer and granulated with the addition of 2.8 kg of H2O. The moist granules hardly baked even after being stored in a bin and were dried while moving in a warm air stream. After the coarse and fine-grain fractions had been sieved, the granules were processed into the finished product by mixing the fractions indicated below:

Perborate monohydrate, compactate 5.5%

A trisodium citrate dihydrad quality with a bulk density of approx. 810 g / 1 was used in the preparation. The bulk density of the finished product was 920 g / l.

Example 2:

The following batch (40 kg) was used in the granulation:

After the solids had been premixed, the aqueous APG solution and then the water were metered in first. Otherwise, the preparation of the granules in this and Examples 3 to 5 was identical to that in Example 1. The preparation was as follows:

The bulk density of the finished product was 894 g / 1.

Example 3:

The granular cleaning additive was partially in the granulation

Norasol®WL 4 from Norsohaas replaces:

Norasol®WL 4 16.4%

Granular cleaning additive 23.1% (as in Example 1)

Sodium bicarbonate, compressed 53.5%

Water 7.0%

The preparation was identical to that of Example 1. The bulk density of the finished product was 890 g / 1. λO

Example 4:

Sodium citrate, which can be either fine-grained or roughly crystalline, was not mixed in during the preparation, but was already used in the granulation:

Granular cleaning additive 20.3% (as in Example 1)

Sodium bicarbonate, compressed 31.0%

Trisodium citrate dihydrate 35.7%

Soda, compressed 3.2%

APG 225 (35% ιg) 5.9%

Water 3.9%

The bulk density after processing was 920 g / 1:

The non-ionic surfactant Plurafac® was used as the granulating liquid:

Granular cleaning additive 29.1 (as in Example 1)

Sodium bicarbonate, compressed 52.4

Soda, compacted 9.8

Plurafac®LF 403 1.5

Water 7.2

In the preparation, perborate was replaced by percarbonate, which can be stabilized:

The bulk weight of the finished product was 900 g / 1.

Example 6:

Instead of the granular cleaning additive, Sokalan®CP5 granulate from BASF was used in the granulation:

Sokalan®CP5 granules 17.5% sodium bicarbonate, compressed 60.0% soda, compressed 18.1%

Water 4.4%

The bulk density of the finished product was 890 g / 1.

Example 7

In the granulation, instead of the granular cleaning additive

Sokalan ®CP5 granules from BASF used:

Sokalan ® CP5 granules 17.5%

Sodium bicarbonate, compressed 60.0%

Soda, compressed 18.1%

Water 4.4%

After the addition of water, the wet granules were mixed with 0.5-2% fine-grained soda and then processed further in accordance with Example 1.

The preparation was also carried out as in Example 1. The bulk density of the finished product was 940 g / 1.

The following tests were carried out for comparison with the prior art: AZ

Recipe I was a commercially available, highly alkaline formulation with metasilicate and phosphate. The pH of a 1% solution was 12.5.

Recipe II was a low alkaline formulation according to DE 41 37 470. A 1% solution of this cleaner had a pH of 10.5. Cleaner II contained the weaker alkaline carbonate and disilicate instead of metasilicate.

Recipe III was a weakly alkaline formulation according to the present invention with a pH of 9.5 (1% by weight aqueous solution). Compared to the prior art, it contained large amounts of sodium bicarbonate.

Recipe IV was an even weaker alkaline formulation according to the present invention with a pH of 9.2 (1% by weight aqueous solution).

Table I lists the recipes for the four cleaners, which differ significantly in their alkalinity.

Table II shows a comparison of the cleaning results of the four formulations. This list shows that, surprisingly, the weakly alkaline cleaner also delivers a well-tolerable dishwashing result. The slight underperformance is largely compensated for by the high ecological value of the formulation.

Table III shows a comparison of the precipitation formation of the four cleaning agents with different pH values in hard water.

Test conditions:

Dishwasher Miele G 590 55 ° C universal program detergent dosage 25 g

Assessment: Grading scale from 0-10 0 no cleaning 10 optimal cleaning 3-fold assessment by 4 test persons A3

Determination of precipitation:

Dishes (glasses, porcelain, stainless steel cutlery) are washed 10 times in the dishwasher. 50 g of mixed soiling (starch, protein) is added to the machine with each rinse. Rinsing is carried out in a 65 ° C program under hard water conditions (16 ° d). 20 g of detergent are dosed from the storage container in the main wash cycle per wash cycle.

Evaluation:

After 10 attempts to rinse, the dishes are assessed in the "black box". The scale ranges from 0 to 10. 0 means that no deposits were found on the dishes. The rubbers up to grade 5 are only visible in the "black box". Rubbers from grade 6 are also outside, i.e. also visible to the consumer.

The interior of the machine is assessed according to the same grading scheme as the dishes, so that two values are obtained.

Table I

Recipes

Ingredients II III IV

% By weight

Table III Comparison of the Lime Precipitation Formulations I II III IV

Claims

Patent claims

1. A process for the preparation of low-alkaline, active chlorine, silicate and phosphate-free cleaning agents for automatic dishwashing containing builder substances, bleaching agents, water, if appropriate nonionic surfactants and other conventional constituents of such agents, characterized in that the builder substances Sodium salts of mono- or copolymeric (meth) acrylic acids, premixed with sodium carbonate and sodium bicarbonate in any mixer, agglomerating granulated with the addition of liquids, the granules obtained in this way optionally adjusted to a uniform particle size distribution in a second granulation stage, with the addition of be Dries movement in a warm air stream, sieves fine and coarse-grained fractions and then mixed with the bleaching agent and, if appropriate, a bleach activator, a bleach stabilizer, fragrance, enzymes, non-ionic surfactants, further builders and / or dyes.

2. The method according to claim 1, characterized in that powdered and / or liquid poly (meth) acrylate and / or granular, alkaline cleaning additive according to DE 3937469 is used as the sodium salts of mono- or copolymeric (meth) acrylic acids.

3. The method according to claim 1 and 2, characterized in that the finished granules are admixed as a further structural substance sodium citrate.

4. The method according to claim 1 to 3, characterized in that the sodium citrate is already added to the premix to be granulated.

5. The method according to claim 1 to 4, characterized in that water is used as the liquid for granulating.

6. The method according to claim 1 to 5, characterized in that non-ionic surfactants are used for granulation as the liquid.

7. The method according to claim 1 to 6, characterized in that liquid sodium salt solutions of mono- or copolymeric (meth) acrylic acids are used for granulation.

8. The method according to claim 1 to 7, characterized in that compressed sodium carbonate is used as sodium carbonate.

9. The method according to claim 1 to 8, characterized in that one uses sodium bicarbonate in compressed form.

10. The method according to claim 1 to 9, characterized in that one selects the ratio of sodium carbonate to sodium bicarbonate so that the detergent has a pH of about 9 to about 10 in 1 wt .-% aqueous solution.

11. Agent produced according to one of claims 1 to 9, characterized by a content of

5-30% by weight poly (meth) acrylate 10-50% by weight trisodium citrate dihydrate

2.5-20% by weight of alkali carbonate 10-60% by weight of alkali bicarbonate

3 - 15% by weight bleach

0 - 4% by weight bleach activator

0 - 4% by weight bleach stabilizer

0-4% by weight nonionic surfactant

0-2% by weight protease

0-2% by weight of a ylase

0-2% by weight lipase

0 - 1 wt% fragrance

0-1% by weight of dye

3 to 15% by weight of water, all of the constituents used making up a total of 100% by weight and having a pH of about 9 to about 10 in 1% by weight aqueous solution.