WO1997016526A1

WO1997016526A1 - Method of producing soil-release granulates

Info

Publication number: WO1997016526A1
Application number: PCT/EP1996/004596
Authority: WO
Inventors: Vincenzo Violante; Fred Schambil; Georg Meine
Original assignee: Henkel Kommanditgesellschaft Auf Aktien
Priority date: 1995-10-31
Filing date: 1996-10-23
Publication date: 1997-05-09
Also published as: DE19540524A1

Abstract

The object of the invention is to develop a very simple method of producing granulated washing agent constituents which can be poured or sprinkled and contain a soil-release polymer. This object is substantially achieved by adding the soil-release polymer to an aqueous solution containing a film-forming polymer, admixing inorganic carrier material and spray-drying the resultant aqueous suspension.

Description

Process for the production of dirt-dissolving granules

The present invention relates to a process for the production of granular detergent components which can be stoked and free-flowing and which contain a dirt-releasing polymer and an essentially inorganic carrier material, and the use of granules produced in this way for the production of solid detergents and cleaning agents.

In addition to the ingredients that are indispensable for the washing process, such as surfactants and builder materials, detergents generally contain further constituents which can be summarized under the term washing auxiliaries and which include such different active ingredient groups as foam regulators, graying inhibitors, bleaching agents, bleach activators and color transfer inhibitors. Such auxiliary substances also include substances which impart dirt-repellent properties to the laundry fiber and which, if present during the washing process, support the dirt-removing ability of the other detergent components. The same applies analogously to cleaning agents for hard surfaces. Such dirt-releasing substances are often referred to as "soil-release" active ingredients. Because of their chemical similarity to polyester fibers, particularly effective anti-soiling agents, but which can also have the desired effect on fabrics made of other materials, are copolyesters which contain dicarboxylic acid units, alkylene glycol units and polyalkylene glycol units. Soil-removing copolyesters of the type mentioned and their use in detergents have been known for a long time.

For example, German Offenlegungsschrift DT 16 17 141 describes a washing process using polyethylene terephthalate-polyoxyethylene glycol copolymers. German laid-open specification DT 22 00 911 relates to detergents which contain nonionic surfactant and a copolymer of polyoxyethylene glycol and polyethylene terephthalate. In the German patent application DT 22 53 063 acidic textile finishing agents are mentioned, which are a copolymer of a dibasic carboxylic acid and an alkylene or cycloalkylene polyglycol and optionally an alkylene or cycloalkylene glycol. European patent EP 066 944 relates to textile treatment compositions which contain a copolyester of ethylene glycol, polyethylene glycol, aromatic dicarboxylic acid and sulfonated aromatic dicarboxylic acid in certain molar ratios. European or European patent EP 185 427 describes methyl or ethylene end-capped Polvester with ethylene and / or propylene t-phthalate. and polyethylene oxide terephthalate units and detergents containing such soil release polymer are known. European patent EP 241 984 relates to a polyester which, in addition to oxyethylene groups and terephthalic acid units, also contains substituted ethylene units and glycerol units.

If the compounds or classes of compounds mentioned are known to have good activity, however, the substances which are generally solid at room temperature have disadvantages with regard to their incorporation into solid detergents or cleaning agents. A preferred manufacturing process for such agents is spray drying an aqueous slurry of its components. When the above-mentioned dirt-releasing substances are also sprayed after their previous incorporation into the aqueous slurry, there is generally an intolerable loss of activity of the mentioned dirt-releasing substances, which may not be sufficiently stable in the conventional aqueous slurries because of their ester function content . For this reason, it has been proposed, for example in US Pat. No. 4,569,772, to spray-cool a melt of the compound which is able to remove dirt, which compound was additionally stabilized there by means of polyacrylate, or to cool it after cooling, and to wash the particles produced in this way with detergents to mix. However, because of the proportions of such particles required only in small amounts in the finished agent, homogeneous mixing into solid detergents makes difficulties. German published patent application DE 33 24 258 therefore proposes a solution or dispersion of dirt-releasing spraying rich active ingredient in nonionic surfactant onto a builder-containing detergent particle. This procedure leads to agents which must contain non-ionic surfactant in any case, which limits the freedom from recipes. In addition, there is a risk of the sprayed particles sticking together due to the low-melting point nonionic surfactant on their surface. These disadvantages can largely be caused by the German. Patent application DE 44 08 360 known methods can be avoided, in which a dirt-releasing polymer which is solid at room temperature and which contains ethylene terephthalate and polyoxyethylene terephthalate groups is heated to a temperature at which it has a viscosity below 5,000 mPas, and the surfactant-free polymer ¬ applies melt to a finely divided carrier material while observing special process parameters.

The object of the present invention was to develop an alternative, as simple as possible process for the production of pourable and free-flowing granular detergent components which contain a dirt-releasing polymer.

The invention relates to a process for producing pourable and free-flowing granular detergent components which contain a dirt-releasing polymer by adding the dirt-releasing polymer to an aqueous solution which contains a film-forming polymer, admixing inorganic carrier material and spray-drying the aqueous slurry obtained in this way.

The water content of such an aqueous slurry is preferably in the range of 30% by weight to 50% by weight. The mixing time of both the dirt-releasing polymer with the film-forming polymer and the polymer mixture with the carrier material is largely uncritical and is normally in the range from 5 minutes to 30 minutes. The pH of the aqueous slurry intended for spray drying is preferably adjusted to values below 11, in particular in the range from 6 to 10 and particularly preferably in the range from 7 to 9. This slightly acidic to weakly alkaline pH range can be adjusted by using a film-forming polymer that contains non-neutralized carboxylic acid groups, or by adding additives that are compatible with the system or acidic salts WIP * 7i ^ιι rπ RC _* SΓ * Ϊ ?! ^^ - "w _^ fe 'acid alkali hydrogen sulfate or citric acid, if the aqueous mixture of the above components does not already have a pH in the range mentioned.

The process according to the invention can be carried out using known systems, so-called spray towers. The procedure according to the invention is preferably carried out in such a way that the mixing steps are carried out at temperatures below 90 ° C., in particular in the range from 60 ° C. to 75 ° C. The process according to the invention is preferably carried out using drying gases, which are preferably conducted in countercurrent to the spray product to be dried, at temperatures in the range from 250 to 300 ° C., measured at the hottest point of the spray tower, the so-called ring channel. This leads to water contents in the spray-dried product of normally not more than 10% by weight.

In a preferred embodiment of the process according to the invention, the dirt-releasing polymer, if it is solid at room temperature, is not added as a solid to the slurry to be sprayed, but is first heated to a temperature at which it is in a flowable state. This softening temperature of the polymer, which can be determined by known methods, for example by means of DSC, is preferably in the range from 40 ° C. to 80 ° C. The dirt-releasing polymers preferably have molar masses in the range from 500 to 1,000,000, in particular from 600 to 100,000. In the process according to the invention, in addition to cationically modified polyacrylates, preference is given to using such dirt-releasing polymers which contain ethylene terephthalate and polyoxyethylene terephthalate groups in Molar ratios from 9: 1 to 1: 9 included. 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 dirt-releasing polymer. End-capped derivatives, that is to say polymers which have neither free hydroxyl groups nor free carboxyl groups, but instead carry, for example, C _M alkyl groups or are terminally esterified with Einhasipen Carbnnςäiirep, for example benzoic acid or sulfobenzoic acid, can be used in the process according to the invention. Also suitable are the polyesters known from EP 241 985, 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 Cp to C ₄ alkyl groups are end group-capped, the soil-release polymers used in EP 253 567 with a molecular weight of 900 to 9,000 made of ethylene terephthalate and polyethylene oxide terephthalate, the polyethylene glycol units having molecular weights of 300 to 3,000 and the molar ratio from ethylene terephthalate to polyethylene oxide terephthalate is 0.6 to 0.95, the polyesters known from EP 272 033, which are at least partially end group-capped by C _M alkyl or acyl radicals with poly-propylene terephthalate and polyoxyethylene terephthalate units, which in EP 274 907 called sulfoethyl end group-capped terephthalate-containing soil release polyesters, the soil release poles produced by sulfonation of unsaturated end groups Yester with terephthalate, alkylene glycol and poly-C ₂ _, - glycol units of EP 357 280, the cationic soil release 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 from EP 398 137. Likewise suitable are polymers of ethylene terephthalate and polyethylene oxide terephthalate, in which the polyethylene glycol units have molecular weights of 750 to 5,000 and the molar ratio of ethylene terephthalate to polyethylene oxide -terephthalate is 50:50 to 90:10 and its use in detergents is described in German patent DE 28 57 292, as well as polymers with molecular weight 15,000 to 50,000 from ethylene terephthalate and polyethylene oxide terephthalate, the polyethylene glycol units having molecular weights of 1000 to 10,000 and the molar ratio of ethylene terephthalate to polyethylene oxide terephthalate being 2: 1 to 6: 1, which according to DE 33 24 258 in Detergents can be used. Dirt-releasing polymers are widely available commercially and are offered, for example, by the companies BASF, Du Pont, ICI, Huls, Rhone-Poulenc and Rohm & Haas, for example under the names Milease®, Sokalan®, Velvetol® and Zelcon®.

Both water-insoluble substances such as detergent-quality zeolites, in particular zeolite-A, zeolite-X and / or zeolite-P, and water-soluble substances such as alkali metal sulfates, alkali metal carbonates, alkali metal bicarbonates, silicas and alkali metal silicates, which can be amorphous or crystalline, come as carrier materials. into consideration. Alkali sulfates and / or zeolites are preferably used. Preferred alkali metals include sodium and potassium.

To a certain extent, normally in amounts of not more than 50% by weight, in particular from 0.5% by weight to 25% by weight, in each case based on the total carrier material, organic carrier substances can also be used in the process according to the invention , which in addition to monomeric polycarboxylate such as alkali citrate primarily include the film-forming polymers mentioned. Such film-forming polymer is preferably present in granules produced by the process according to the invention in amounts of 5% by weight to 75% by weight, in particular from 10% by weight to 50% by weight.

The film-forming, generally water-soluble and organic polymers include, for example, cellulose and starch ethers, such as carboxymethyl cellulose, carboxymethyl starch, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose and corresponding cellulose mixed ethers. Optionally, gelatin, casein, tragacanth, maltodextrose, sucrose, invert sugar, glucose syrup, alkylated polysaccharides or other water-soluble or readily dispersible polymers of natural origin can be used. Usable synthetic polymers are polyethylene glycol, polyacrylates, polymethacrylates, copolymers of acrylic acid with maleic acid or compounds containing vinyl groups, furthermore polyvinyl alcohol, polyvinyl acetate and polyvinyl pyrrolidone, which can also be present in at least partially saponified form. Insofar as it is the case with the aforementioned prevention M VerhP those with free C_rboxy! Gruppcr. acts, they can usually be in the form of their alkali metal salts, especially the sodium salts. Mixtures of copolymers of acrylic and maleic acid with carboxymethyl cellulose and / or polyvinyl pyrrolidone are preferably used. In addition to the above, other polymer compounds such as polysiloxanes and polyethylene paraffins can be present.

The bulk density of the granules produced by the process according to the invention is normally about 300 g / 1 to 700 g / 1. The process according to the invention makes it easy to produce free-flowing, free-flowing granules with high contents of polymer capable of dirt release. Based on the resulting granules, 15% by weight to 75% by weight, in particular 20% by weight to 60% by weight and particularly preferably 30% by weight to 60% by weight, of dirt-releasing polymer are introduced the granules.

The granules produced by the process according to the invention can be used without problems for the production of solid, in particular powder, but also tablet-type detergents and cleaning agents. In the simplest case, it is admixed with the other components present as powder or in other particulate form, but can also be subsequently compressed or extruded in a mixture with these in a known manner. For the last-mentioned procedure, use is preferably made of the method having an extrusion step, which is known from European Patent EP 486 592. Examples

example 1

In a mixing vessel were 654 kg aqueous sodium carboxymethylcellulose solution (6.12 weight percent), 70 kg of water glass solution (35 weight percent) and a wäß¬ membered solution 40 kg of polymeric polycarboxylate (Sokalan ^® CP5; 40 weight percent) were provided and up to 75 ° C preheated. 400 kg of a commercially available dirt-releasing ethylene-terephthalate-polyoxyethylene terephthalate polymer, which had previously been heated to a temperature of 70 ° C., were added and homogeneously mixed in by stirring within 5 minutes. Then 1,484 kg of sodium sulfate were added with constant stirring. The slurry thus produced was spray-dried at a temperature of 270 ° C., measured in the ring channel of the spray tower, under a pressure of 45 bar using drying gases in countercurrent to a water content of approximately 2% by weight. 2,000 kg of a white powder (Pl) with an average bulk density of 700 g / l were obtained, which consisted of at most 5% by weight of particles larger than 1.6 mm and at most 7% by weight of particles of size existed below 0.1 mm.

Example 2

The granules P1 produced in Example 1 were tested in comparison to a product VI, which contained 50% by weight of the same dirt-releasing active ingredient and 50% by weight sodium sulfate, VI by stirring sodium sulfate into the polymer melt and Grinding was produced after the mixture had cooled. For this purpose, by mixing each type of granulate with a detergent WI or W2 prepared according to EP 486 592 and free of dirt-releasing polymer, the detergents WI and W2 were used to test the cleaning performance in washing tests with standardized artificial soiling Application conditions (drum washing machine Miele W 913, 1 -cloth normal program at 40 ° C, 3.5 kg clean laundry, water hardness 16 ° d, dosage of the agent to be tested 80 g; evaluation by remission measurement at 460 nm, without UV). The reflectance values given in Table 2 were the average of 3 determinations each. The values for the detergent W3 free from dirt-releasing polymer are given in the table? also specified.

Table 1: Composition of the agents [% by weight]

Table 2: Remission of the washed test rifles [%

It can be seen that a detergent with a dirt-releasing polymer granulate produced by the process according to the invention has a significantly higher washing performance than a detergent which contains a corresponding granulate, but produced by another process.

Claims

Patent claims

1. Process for the production of pourable and free-flowing granular detergent components which contain a dirt-releasing polymer by adding the dirt-releasing polymer to an aqueous solution which contains a film-forming polymer, admixing inorganic carrier material and spray-drying the aqueous slurry thus obtained.

2. The method according to claim 1, characterized in that the water content of the aqueous slurry is in the range of 30 wt .-% to 50 wt .-%.

3. The method according to claim 1 or 2, characterized in that the pH of the aqueous slurry provided for spray drying is adjusted to a value below 11, preferably in the range from 6 to 10 and in particular in the range from 7 to 9.

4. The method according to any one of claims 1 to 3, characterized in that one carries out the mixing steps at temperatures below 90 ° C, in particular in the range from 60 ° C to 75 ° C.

5. The method according to any one of claims 1 to 4, characterized in that the mixing time of both the dirt-releasing polymer with the film-forming polymer and the polymer mixture with the carrier material is in each case in the range of 5 to 30 minutes.

6. The method according to any one of claims 1 to 5, characterized in that a dirt-releasing polymer is used which contains ethylene terephthalate and polyoxyethylene terephthalate groups in molar ratios of 9: 1 to 1: 9.

7. The method according to any one of claims 1 to 6, characterized in that one uses a dirt-releasing polymer with a molecular weight in the range of 500 to 1,000,000, in particular from 600 to 100,000.

8. The method according to any one of claims 1 to 7, characterized in that the carrier material from the group comprising alkali sulfates, alkali carbonates. Alkali hydrogen carbonates, silicic acid, alkali silicates, which may be amorphous or crystalline, and alkali alumosilicates, which may also be amorphous or crystalline, optionally in admixture with organic substances, such as alkali citrates, and mixtures thereof.

9. The method according to any one of claims 1 to 8, characterized in that the film-forming polymer from the group comprising cellulose and starch ethers, gelatin, casein, tragacanth, maltodextrose, sucrose, invert sugar, glucose syrup, polyethylene glycol, polyacrylates, polymethacrylates, Copolymers of acrylic acid with maleic acid and compounds containing vinyl groups, as well as polyvinyl alcohol, polyvinyl acetate and polyvinylpyrrolidone, which can also be present in at least partially saponified form, and their mixtures.

10. The method according to any one of claims 1 to 9, characterized in that the bulk density of the granules thus produced is about 300 g / 1 to 700 g / 1.

1 1. Use of pourable and free-flowing granular detergent components, obtainable by the process according to one of claims 1 to 10, which contain a dirt-releasing polymer and an essentially inorganic carrier material, for the production of solid, in particular powder detergents .