EP0944709A1

EP0944709A1 - Method for the production of solid, formed detergent formulations

Info

Publication number: EP0944709A1
Application number: EP97951911A
Authority: EP
Inventors: Hans-Heinrich GRÜNHAGEN; Jörg Breitenbach; Joerg Rosenberg
Original assignee: Knoll GmbH
Current assignee: Abbott GmbH and Co KG
Priority date: 1996-11-29
Filing date: 1997-11-18
Publication date: 1999-09-29
Also published as: DE19649565A1; WO1998023721A1

Abstract

Method for the production of high density detergent formulations that decompose quickly in the washing bath, characterized in that the feed material mixture is subjected to a kneading and mixing process, followed by forming by calendering.

Description

METHOD FOR PRODUCING SOLID, SHAPED DETERGENT FORMULATIONS

description

The present invention relates to methods for producing solid, shaped detergents or cleaning agents, in particular a detergent for textile washing.

In the field of detergents and cleaning agents for household and commercial use, in particular in the field of powder detergents for textiles, there is currently a trend towards the production of products with increased powder bulk weights and of more concentrated mixtures of ingredients.

In particular, granules with a content of carrier substances and liquid or pasty surfactants adsorbed thereon, in particular corresponding non-ionic surfactants, are known from the prior art.

Previously known manufacturing processes are usually complex. First of all, an aqueous slurry of the carrier substance is produced, which then has to be converted into a granular, porous preliminary product by spray drying. The co-spraying of the dirt-releasing substances mentioned and their prior incorporation into the aqueous slurry is generally not possible because of the alkalinity of this slurry, in which the dirt-releasing substances mentioned are normally not sufficiently stable because of their ester functions.

Another problem with the production of detergents with a high bulk density or massive matrices is their rapid disintegration when they enter an aqueous medium. This is a mandatory requirement for successful washing. In this sense, it should be avoided by high local concentration of detergent ingredients such as Bleach to damage the laundry fiber.

EP-A 0518 888 describes the production of solid, free-flowing granules of the constituents of detergents and cleaning agents which can be predetermined in their special shape, while at the same time making it possible to obtain significantly higher bulk densities. However, there is a tee-off technique in the sense of a hot tee. This method has the disadvantage that high dust contents and smearing of the emerging melt strand on the necessary perforated disk lead to deviations in the specification of the product leads. If no uniform distribution of the molding compound to be processed is achieved over the entire cross section of the shaping plate, the compound emerges from the individual openings at different speeds. However, the emerging strands are cut into granules of different lengths by the knife rotating in front of the shaping plate. A uniform product cannot be obtained in this way.

EP-A 0436 786 describes the production of extrudate particles for pharmaceutical granules by a compressed air knock-off technique.

EP-A 0240 904 describes the production of calendered pharmaceutical forms by introducing a thermoplastic melt strip containing active ingredients into a subsequent calendering device consisting of two mold rolls rotating in opposite directions.

The invention was based on the object of developing a method which allows the production of uniform moldings of a detergent or cleaning agent, in particular a detergent for textile washing, in a particularly economical manner.

Accordingly, a process for the production of solid, shaped detergents and cleaning agents has been found, which is characterized in that the mixture of the starting materials is subjected to a kneading and mixing process and, after extrusion, is shaped by calendering.

Solid shaped detergents and cleaning agents in the sense of this invention are agents which have a tablet, pillow, lozenge, almond or briquette shape. They contain at least one component that is solid under the processing conditions, this solid component essentially being inorganic framework substances.

In addition to the ingredients that are indispensable for the washing process, such as surfactants and builder materials, the detergents according to the invention generally contain further constituents which can be summarized under the term washing auxiliaries and which different active substance groups, such as foam regulators, graying inhibitors, bleaching agents, bleach activators, bleaching components, and opt. Brightener u. Auxiliaries, which include graying corrosion, foam inhibitors, enzymes, stabilizers, perfume oils, dyes and adjusting agents, and include color transfer inhibitors. Such auxiliary substances also include substances which give the laundry fiber dirt-repellent properties and which, if present during the washing process, support the dirt-removing ability of the other detergent components.

Such dirt-releasing substances are often called

"Soil-Release" active ingredients. Because of their chemical similarity to polyester fibers, particularly effective dirt-releasing active ingredients, but which can also have the desired effect on fabrics made from other materials, are copolyesters which contain dicarboxylic acid units, alkylene glycol units and polyalkylene glycol units. Soil-release copolyesters of the type mentioned and their use in detergents have long been known (ethylene terephthalate polyoxyethylene terephthalate polymer Velvetol ^®, manufacturer Rhone-Poulenc).

Such dirt-releasing polymers can also be used which contain ethylene terephthalate and polyoxyethylene terephthalate groups in molar ratios of 9: 1 to 1: 9. Other monomer units, for example propylene glycol, polypropylene glycol, alkylene or alkenylene dicarboxylic acids, isophthalic acid, carboxy- or sulfo-substituted phthalic acid isomers can be contained in the soil release polymer. Also end-capped derivatives, that is to say polymers which have neither free hydroxyl groups nor free carboxyl groups, but instead carry, for example, C ₄ -alkyl groups or with monobasic ones

Carboxylic acids, for example benzoic acid or sulfobenzoic acid, which are terminally esterified, can be used in the process according to the invention. Also suitable are the polyesters known from EP241985, which contain, in addition to oxyethylene groups and terephthalic acid units, 1, 2-propylene, 1,2-butylene and / or 3-methoxy-1,2-propylene groups and glycerol units and with Cχ ~ to C ₄ alkyl groups are end-capped, the soil release polymers used in EP 253567 with a molecular weight of 900 to 9000 made of ethylene terephthalate and polyethylene oxide terephthalate, the polyethylene glycol units having molecular weights of 300 to 3000 and the molar ratio of ethylene terephthalate to polyethylene oxide terephthalate is 0.6 to 0.95, the polyesters known from EP 272 033 and at least partially end-capped by C ₄ alkyl or acyl radicals with poly-propylene terephthalate and polyoxyethylene terephthalate units mentioned in EP 274907 Soil-release polyester containing terephthalate containing sulfoethyl end groups, the soil-release polyes produced by sulfonation of unsaturated end groups ter with terephthalate, alkylene glycol and poly-C ₂ _ ₄ -glycol units of EP 357 280, the cationic soil releases polyesters known from EP 398 133 with amine, ammonium and / or amine oxide groups and the cationic soil release polyesters with ethoxylated, quaternized morpholine units of EP 398 137. Also suitable are polymers of ethylene terephthalate and polyethylene oxide terephthalate, in which the polyethylene glycol units have molecular weights of 750 to 5000 and the molar ratio of ethylene terephthalate to polyethylene oxide terephthalate is 50:50 to 90:10 and their use in detergents is described in German patent DE 2 857 292, and polymers with a molecular weight of 15,000 to 50,000 made of ethylene terephthalate and polyethylene oxide terephthalate, the polyethylene glycol units having molecular weights of 1,000 to 10,000 and the molar ratio of ethylene terephthalate to polyethylene oxide terephthalate 2: 1 to 6: 1, which can be used in detergents according to DE 3 324 258.

The detergent or cleaning agent formulations furthermore contain one or more inorganic builders (so-called “builders”) as carrier materials.

Suitable inorganic builders are, for example, aluminosilicates, silicates, carbonates and / or phosphates.

Orthophosphates or polyphosphates, in particular pentasodium triphosphate, can be used as phosphates. Other suitable inorganic builders are carbonates or bicarbonates. These can be used in the form of their alkali, alkaline earth or ammonium salts. Sodium, lithium and magnesium carbonates and bicarbonates are preferably used, particularly preferably sodium carbonate and sodium bicarbonate. Likewise suitable are, for example, aluminosilicates with ion exchange properties (zeolites), especially sodium aluminosilicates. Amorphous or crystalline silicates, such as, for example, disilicates in the form of their alkali metal, alkaline earth metal or ammonium salts, preferably sodium, lithium or magnesium disilicates, can also be used.

The inorganic builders can be used in amounts of 10 to 60, preferably 20 to 50% by weight.

The detergents and cleaning agents preferably also contain organic co-builders in addition to the inorganic builders. As such, nitrilotriacetic acid, citric acid or polycarboxylates are suitable. Suitable polycarboxylates are, for example, copolymers of maleic acid and acrylic acid in a weight ratio of 10:90, preferably 30 to 70 to 90 to 10, with molecular weights of 2,000 to 250,000, preferably 5,000 to 100,000, or terpolymers with molecular weights of 25,000 to 100 000 from maleic acid, acrylic acid and a vinyl ester of a C ₁ -C ₃ carboxylic acid in a weight ratio of 10 (MA): 90 (AS + VE) to 95 (MA): 5 (AS + VE), where the ratio of acrylic acid to vinyl ester can be 20:80 to 80:20% by weight. The organic co-builders are usually used in amounts of up to 15% by weight, preferably 1 to 8% by weight, together with inorganic builders.

The formulations furthermore contain customary surfactants. The tensides reduce the interfacial tension of the water and thereby give the washing solution its great network capacity. They promote the lifting of the dirt and disperse the dirt, i.e. they emulsify the greasy dirt and suspend the pigment dirt. In the preparations according to the invention there is usually a combination of several surfactants, mainly anion. Nature, some are non-ionic.

Within the surfactant combination, special soaps (i.e. soaps made from specially selected long-chain fatty acids) can serve as a means of dampening or regulating foam (foam inhibitors).

Other anionic surfactants are the fatty alcohol (ether) sulfates, alkyl sulfonates, sulfuric acid esters of the ethoxylates of alkyl phenols, sulfosuccinic acid esters and monoglyceride sulfates.

Nonionic surfactants (nonionics, nonionic surfactants) contain fatty alcohols, alkylphenols, fatty acid amides, to the functional groups of which polyethylene oxide chains are attached (ethoxylates). Other types consist of a polypropylene oxide to which ethylene oxide has been condensed on both sides (polyether, e.g. Pluronic) and the fatty amine oxides are also nonionics.

The preferred bleaching agent is sodium perborate, which increasingly releases active oxygen above 60 ° C and which removes a number of contaminants such as e.g. Fruit, vegetable or red wine stains, oxidatively degrades.

So-called perborate activators are used for washing temperatures below 60 ° C, i.e. Acyl compounds that react with H0 in alkaline wash liquors to form peroxyacids: Example: 1,3,4,6-tetraacetylglycoluril.

Optical brighteners (whiteners), which attach to the fiber and convert ultraviolet rays into blue visible light, which compensates for the otherwise yellowish tinge of white laundry. Stilbene, pyrazoline, coumarin and benzoxazole derivatives are used. So-called graying inhibitors (dirt carriers) are used as washing aids, which are intended to prevent the dirt detached from the fiber from being drawn back onto the fiber from the liquor. These include, for example, polyvinylpyrrolidones, copolymers of 5-vinylpyrrolidone and also polymers of vinylpyridine or vinylpyridine-N-oxide. However, cellulose derivatives, in particular carboxymethyl cellulose, are also used.

Alkali silicates (water glass) ensure that the optimal pH value is set for heavy-duty detergents; they have a certain dispersibility and an anti-corrosion effect. Magnesium silicate serves as a stabilizer for perborate bleaching by binding copper, manganese and iron ions.

15 For the use of a detergent in the drum washing machine, foam control by foam inhibitors (see foam inhibitor) is essential, e.g. by soaping longer chain fatty acids (behenate), trialkylmelamine derivative. or silicones (cf. Schmadel and Kurzendörfer (Detergent Chemistry, Heidelberg: Hüthig

20 1976, pp. 121-136). On the other hand, the foam can also be stabilized, e.g. through alkylureas as foam stabilizers. Enzymes, especially alkali-resistant proteases and amylases, for example enzymes, can be added to make it easier to remove protein and starch stains on the laundry

25 such as proteases, lipases, amylases or cellulases as for

Washing and cleaning agents are common, or mixtures of such enzymes. The enzymes are commercially available and are usually used in amounts of 0.1 to 1.5, preferably 0.2 to 1.0% by weight.

30

The formulations can also contain color transfer inhibitors. Suitable color transfer inhibitors are, for example, water-soluble homopolymers of N-vinylpyrrolidone (VP) or of N-vinylimidazole (VI) or copolymers of the monomers mentioned

35 with molecular weights of 2,000 to 50,000. Preferred color transfer inhibitors are crosslinked VI-VP copolymers which contain VI and VP in a molar ratio of 20 to 80 to 90 to 10 and average particle sizes of 0.1 to 500 μm. The color transfer inhibitors are usually used in amounts of 0.05 to 5% by weight, preferably 0.2 to 2.5% by weight.

Trickle aids (anti-caking agents) such as toluenesulfonates are designed to prevent detergents from clogging due to atmospheric moisture. They can also prevent caking of the granules in the granules according to the invention and contribute to better detachment from the calender in the calendered products. The same purpose sodium sulfate, which also acts as a dust-binding agent, also serves as a so-called neutral adjusting agent.

Fragrance substances (perfume oils) have the task of masking lye odors that occur during the washing process and of giving the laundry a pleasant smell, cf. Perfumes and Zilske (Dragoco Rep. 21 (1974) 231-241).

The preparations according to the invention can also contain microbicides, hydrotropes and dyes in small amounts.

In a preferred embodiment, further surfactants can be added to the shaped bodies for additional acceleration of disintegration, for example anionic surfactants such as dodecyl sulfates, cetylstearyl sulfates, dioctyl sulfosuccinates and sulfonates such as alkyl sulfonates, cationic surfactants, amphoteric surfactants such as lecithin and in particular also those with betaine structure such as the tego Betaines, or Steinapol types, and sulfobetaines, non-ionic surfactants such as fatty alcohols and sterols, for example Stearyl alcohol, cetyl alcohol, cetylstearyl alcohol, cholesterol, sorbitan fatty acid esters such as e.g. Sorbitan monooleate, palmitate, and stearate, polyoxyethylene sobitan fatty acid esters such as the polysorbates, polyethylene fatty acid methyl carbonates such as the macrogols, polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohols, glycerol fatty acid esters and macromolecular surfactants such as e.g. Poloxamers and polyethers.

According to the invention, in addition to the 3-20% nonionic and anionic surfactants for the actual washing performance, a further 2-20% of these substances which optimize the acceleration of decay are contained. It is particularly preferably about 5-10.

To produce calendered molds, which can either have a tablet, pillow, lozenge, almond or briquette shape, the strand emerging from an extruder / or kneader or conveyed by a pump is introduced into two opposing calender rolls, either either or only one of the calender rolls can have a shaping depression.

If during the actual extrusion or kneading process a liquid, e.g. If water is added, for example, a drying step can be connected after the shaping step in which the rounded or calendered forms are dried, for example in a fluidized bed granulator. Alternatively, it is also possible to set the proportion of liquid component in the mixture during the extrusion process by means of a vacuum advance by controlling the temperature and vacuum conditions. The ability of the limited liquid content in the mixture of substances to soften plasticization increases with increasing temperature.

The external appearance of the processing step according to the invention is similar to the plasticization of plastic granules to give the molding compound. Just as there, a limited increase in the mass temperature can also support the homogenization and compression of the primarily occurring dry-appearing mixture of substances to form-compressible mass. The intensive mixing process, for example by kneading, can in itself lead to the desired temperature increase. If necessary, a targeted temperature regulation can also be carried out from the outside. This happens e.g. about the individual shots of the extruder barrel. A distinction must be made between molding compositions which contain temperature-sensitive substances or not. The temperature of the molding compound rises due to the energy input during the extrusion, so that cooling must take place, in particular when extruding the former molding compound, in order to avoid decomposition.

According to the invention, it is possible to add further components to the extruder / kneader at any time during the extrusion or kneading process. It can e.g. are aqueous solutions or dispersions of enzymes that would not withstand a strong kneading / shearing action of the process in critical zones. Such metering can be pumped into the individual shots e.g. of the extruder.

The screws can be arranged in the same or opposite directions, non-intermeshing, intermeshing or closely intermeshing. A co-rotating combing arrangement is preferred.

It is also possible to flange onto the extruder by means of a side-mounted machine and the associated mixture or pre-product feed via another extruder or another kneading / mixing and pumping combination.

First of all, a premix of the solid and the possibly used limited proportions of liquid components can be prepared in a manner known per se. In this way, tower powders obtained by spray drying can also be easily mixed with one another in the finely divided state as pure substances. The total mass of the premix is briefly remixed, the respective proportions being selected so that a preferably free-flowing premix is obtained which is suitable for charging a homogenizing system.

However, in order to be able to operate the process continuously at high throughput, it is preferred to use the components of the end product e.g. to be dosed into the extruder or kneader via a differential weighing system. In this way it is also possible to refill the metering devices during the extrusion process.

Depending on the quality of the material, the required amount of liquid phase and the plasticizer and lubricant selected according to the invention are mixed in as a preferably aqueous paste or detergent gel. If desired, further solid components can also be added to the premix or metered in the extruder via separate metering devices. Water is preferably used as the plasticizer, the water content of the formulation during the kneading and mixing process being 0.1 to 15% by weight.

Kneaders of any configuration are preferred as the homogenizing device, which also e.g. used in plastics technology for mixing, e.g. such devices are used in "Mixing in the manufacture and processing of plastics", H. Pahl, VDI-Verlag, 1986 are used. For example, extruders, dynamic and static mixers, stirred tanks, single-shaft and multi-shaft agitators and preferably mixing-kneading reactors from List, extruders from Buss AG with single-shaft oscillating drive and single- or double-shaft extruders from Werner and Pfleiderer can be used.

The configuration of the extruders or kneading screws can be varied as required. In the optimized case, it should guarantee economically rapid conveyance with sufficient mixing of the matrix and sufficient energy input. For this reason, conveying, kneading and mixing elements with a coordinated web width, aisle depth, aisle pitch and aisle direction are to be combined. It can be expedient in the homogenization step to adjust the material to be pressed to moderate temperatures, for example to 35 to 80 ° C., temperatures of 45-60 ° C. are preferred. Under the shearing action of the kneading device, the premix is plasticized in a compacting manner and is then discharged through the bores into fine strands or through a slot die to form a band.

These strands or bands are cut to the extent of their formation into calendered products of the desired dimension. For the calendered products, depending on the shape, sizes from 3 mm x 3 mm x 3 mm up to 6 cm x 6 cm x 6 cm are preferred, but 1-2 cm (height) x 3-5 cm (width) x 3 -5 cm (depth) can be manufactured.

An advantage of the method is the manifold possibility of shaping the products according to the invention from the shaping process.

According to the invention, the following method is particularly suitable for carrying out this shaping method step:

This is fed, preferably continuously by means of a differential weighing system, to a 2-screw kneader / extruder, the housing and the extruder / die head of which are adjusted to the predetermined extrusion temperature, for example to a max. Are heated to 60 ° C. The individual temperature zones form the following temperature profile, for example:

Shot 1 30 ° C

Shot 2 40 ° C

Shot 3 50 ° C

Shot 4 50 ° C

Shot 5 50 ° C

Nozzle: 60 ° C

The product belt emerging through a slotted nozzle is fed into a calendering device which consists of two shaping rollers, each of which carries a half-shape of the finished product as a depression.

The calendering device can optionally be cooled or heated for better processing. In this way the removal of the product forms can be controlled.

The calendering is carried out at melt temperatures in the range between 25 and 75.degree. C., preferably between 30 and 70.degree. C., and the escaping ones by cooling - in particular by means of cold air plasticized strands cool and dry at least superficially before and / or during their cutting.

Cooling, in particular with cold air directly after the molding compound tape emerges, is only necessary if a partial removal of surface water from the masses to be calendered is required.

Round tablets, 1.5 cm in height and 3.5 cm in diameter, are formed from the calendered product strand and, after calendering, are placed on an air belt for further cooling. To remove the press seam, they can optionally be treated in a mixer or in a fluidized bed.

The extrusion and calendering process also makes it possible to produce multi-layer molds that can release their contents in several stages. This is e.g. to a coextrusion in which different layers are brought together and then e.g. can be brought into the desired preparation form by calendering or punching.

Another problem is the uniform distribution of the mass to be processed over the entire cross-section of the shaping plate of the pelletizing head or the nozzle bar containing the nozzle-like bores. This problem can be solved by means of a nozzle, the gap of which can be regulated via a membrane, as it is is known in the literature under the term leaf spring membrane.

With the aid of the method according to the invention, shaped detergent and cleaning agent formulations can be produced in a simple and economical manner. Surprisingly, even water-containing formulations with a relatively high proportion of inorganic framework materials can be processed quickly and safely into uniform, compact moldings. The shaped bodies show no tendency to stick and spontaneously detach from the recesses of the calender rolls.

example

Manufacture of detergent in tablet form

The feedstocks were used in the following amounts:

Surfactant mixture 17.3% calcined soda 20.0% zeolite 31.3% by weight MA-AS copolymer ¹ '8.6% by weight alkylbenzenesulfonate paste ² ' 15.0% by weight

Lecithin 5.0% by weight Na ₂ S0 ₄ 2.8% by weight

¹¹ copolymer of 30% by weight maleic acid and 70% by weight acrylic acid ²⁾ 55% by weight -% aqueous paste

The feed materials were metered into a twin-screw extruder (ZSK 30, Werner & Pfleiderer) using a continuously operating metering device. Furthermore, water (5 ml / min) was metered in continuously as a softening additive which kept the mass extrudable.

Shot 1 30 ° C

Shot 2 40 ° C

Shot 3 50 ° C

Shot 4 50 ° C

Shot 5 50 ° C

Nozzle: 60 ° C

In shot 4, a vacuum of 100-300 mbar was simultaneously applied.

Calendering:

The extrudate tape was drawn through a slot die into a roller calender which presses the tablet form out of the tape. The pressed form usually falls out of the calender roll. For further cooling, the product runs on a belt that is charged with cold, conditioned air. The ridges and edges are then removed by a process in the mixer. The fines obtained there could be recycled again and returned to the process.

Claims

claims

1. A process for the preparation of solid, shaped detergent formulations, characterized in that the mixture of

Feedstocks are subjected to a kneading and mixing process and, after extrusion, are shaped by calendering.

2. The method according to claim 1, characterized in that the kneading and mixing process is carried out in an extruder.

3. The method according to claim 1 or 2, characterized in that the calendering is carried out by two counter-rotating rollers, each with a half-shape of the detergent body.

4. The method according to claim 1 or 2, characterized in that the calendering is carried out by two counter-rotating rollers, only one roller being provided with a shaping depression, while the other roller has a smooth surface.

5. The method according to any one of claims 1 to 4, characterized in that the mixture of feed materials water is continuously added as a plasticizer.